Value of Fine Needle Aspiration Biopsy of Salivary Gland Masses in Clinical Decision-Making Keith S. Hellcr, MD, Sanford Dubner, MD, Quintus Chess, MD, Joseph N. Attic, MD, NewHydePark,NewYork
The accuracy of fine needle aspiration biopsy (FNAB) in the diagnosis of salivary tumors has been well established. This study was undertaken to determine the impact of FNAB on patient management. One hundred one patients underwent FNAB of major salivary gland masses. The physician's initial clinical impression was compared with the FNAB diagnosis and the final diagnosis in each case. Forty patients had solitary masses thought to be benign tumors other than Warthin's tumors. FNAB in 13 of these patients (33%) yielded a diagnosis permitting modification of the planned procedure. The diagnosis of Warthin's tumor was suspected clinically in 23 patients. In nine of these patients ( 3 9 % ) , FNAB resulted in a different diagnosis. Of the 10 patients believed to have malignant tumors, using FNAB, 1 was found to have sialadenitis and 1 a lymphoma. Overall, FNAB resulted in a change in the clinical approach to 35% of the patients. We recomm e n d the performance of FNAB in almost all patients with salivary masses.
he accuracy of fine needle aspiration biopsy (FNAB) in the diagnosis of salivary tumors has been well T established [1--8]. Many surgeons, however, do not routinely perform this test on salivary gland masses because of the possibility of complications, the difficulty of distinguishing among various types of salivary tumors, or the assumption that the result of the FNAB will not change the management of the patient. Some authors strongly advise against FNAB of salivary gland masses [9,10]. The ultimate value of any diagnostic test is its ability to determine and perhaps modify the patient's further management. Not aH salivary gland masses require removal. Some benign parotid tumors or intraparotid lymph nodes can be removed without parotidectomy [1,11]. This study was designed not simply to confLrm the accuracy of FNAB of salivary gland masses but to determine its impact on patient management.
PATIENTS AND METHODS The medical records of all patients referred to the authors for evaluation of major salivary gland masses between June 1987 and December 1991 were reviewed. One hundred one patients were identified in whom FNAB was performed as part of their initial evaluation. Due to the individual preferences of the authors, not all patients underwent FNAB. Included in this series, however, is a group of 52 consecutive patients treated by 2 of the authors (KSH, SD), all of whom had FNAB. Patients in whom the diagnosis of sialadenitis was clinically obvious were not included in this study. FNAB was performed without local anesthesia by a free-hand technique, using a 10-mL syringe without a holder and a 22-gauge needle. A single skin puncture with multiple passes through the tumor while aspirating the syringe was performed. At least eight smears of each aspirate were prepared. Direct smears were immediately fixed in 95% ethanol and stained according to a standard Papanicolaou method. All smears were interpreted by a single cytopathologist (QC). Cytologic findings were characterized as benign if they were stated to be benign or if minimal atypia was described. They were considered malignant if so described in the report or if they were stated to be "suspicious for malignancy." Further management of the patient was based on the result of the FNAB in conjunction with the patient's history and physical findings. The hospital records of all patients who underwent further surgery of the salivary glands were reviewed, and the surgical pathologic findFromthe Headand NeckService,Departmentof Surgery,LongIsland ings were compared with the initial clinical impression JewishMedicalCenter,New HydePark,New York. before the results of the FNAB were obtained and with Requestsfor reprintsshouldbe addressedto KeithS. Heller,MD, the FNAB cytology report. Patients who did not undergo 200 MiddleneckRoad,Great Neck,New York 11021. Presentedat the ThirdInternationalConferenceon Headand Neck surgery were followed up with regular physical examinaCancer,San Francisco,California,July26-30, 1992. tions. In these patients, the diagnosis that was established THE AMERICANJOURNAL OF SURGERY VOLUME164 DECEMBER1992 667
HELLER ET AL
TABLE l
Correlation of Cytologic and Final Diagnosis With Clinical Impression--Benign T u m o r ( O t h e r Than Warthin's Tumor) FNAB Diagnosis Correct Incorrect Benign mixed tumor Warthin's tumor Malignant tumor Lymphoid (benign) Lymphoma Sialadenitis Cyst Benign spindle cell Benign (NOS) Nondiagnostic Hemangioma Lipoma Total
15 4 1 4 1 3 1 1 -4**,tt,**,w167 --34
1* 2t,$ 2$,w -1 ---It ---6
Final Diagnosis 17 4 (2 observed) 4 5 (3 observed) 1 4 (3 observed) 1 (observed) 2 (1 observed) __ -1 1 40
FNAB = fine needle aspiration biopsy; NOS = not otherwise specified. Correct final diagnosis of patients with indeterminate or incorrect FNAB diagnosis: *Adenoid cystic cancer. tAcinic ceil cancer. tBenign mixed tumor. w **Schwannoma. ttLympbadenitis. ~Lipoma. ~Hemangioma.
T A B L E II
Correlation of Cytologic and Final Diagnosis W i t h Clinical Impression--Warthin's Tumor FNAB Diagnosis Correct Incorrect Warthin's tumor Malignant tumor Cyst Lymphoid Lipoma Nondiagnostic Benign tumor Total
14 -2 3 1 2t,$ -22
-1" -----1
Final Diagnosis 14 (8 observed)
-2 (2 observed) 3 (1 observed) 1 1 2 23
FNAB = fine needle aspiration biopsy. Correct final diagnosis of patients with indeterminate or incorrect FNAB diagnosis: *Benign mixed tumor. tOncocytoma. tObse~ed,
by FNAB was assumed to be conf'm-ned if the clinical course was consistent with this diagnosis. All 101 patients were retrospectively classified into 5 groups (benign tumor other than Warthin's tumor, Warthin's tumor, malignant tumor, lymphoid, miscellaneous) based on the initial clinical diagnosis before the results of FNAB were obtained. The result of the FNAB and the final diagnosis for each patient in these groups are detailed in Tables k IL and IIL 668
T H E A M E R I C A N J O U R N A L OF SURGERY
Sensitivity is defined as the ratio of true-positive resuits to all masses conFmned to have a specific diagnosis. Specificity is defined as the ratio of correct final diagnoses to the number of cases with that diagnosis on FNAB. RESULTS A specific cytologic diagnosis was made in 95 of 101 FNABs that were performed (95%). Five percent of FNABs were nondiagnostic. In 12 patients, the result of the FNAB was incorrect (12%). The sensitivity of FNAB for the diagnosis of benign, non-Warthin's salivary tumors in this series is 90% and for malignant salivary tumors, excluding lymphoma, 63%. The specificity was 92% for benign tumors and 62% for malignant tumors. In 40 patients, the clinical diagnosis of a benign salivary tumor was made based on history and physical findhags. Patients in this category would normally be treated by superficial parotidectomy or submandibular dissection. Tumors thought to be Warthin's tumors based on their location, multifocality, and the age and sex of the patient were not included in this group. The diagnosis of benign, non-Warthin's salivary tumor was supported by FNAB in only 17 patients (Table I). In 13 patients (33%), either lesser surgery (excision of Warthin's tumors and lymph nodes) or no surgery (some Warthin's tumors, lymphadenitis, sialadenitis, and cysts) was possible. FNAB yielded incorrect diagnoses in 6 of these 40 patients (15%). Included were two patients with FNAB diagnoses of benign tumors that were found at surgery to be low-grade carcinomas, two patients thought to have Warthin's tumors, one of whom at surgery had an acmic cell cancer and the other a benign mixed tumor, and two patients with FNAB diagnoses of malignant tumors, one of whom was found to have a benign mixed tumor and the other sialadenids. Because the superficial parotidectomy or submandibular dissection rec~ommended for benign, non-Warthin's tumors would have been adequate for the malignant tumors, in only the two patients with a cytologic diagnosis of Warthin's tumor would reliance on the results of FNAB have resulted in inadequate surgery. The clinical diagnosis of Warthin's tumor was made in 23 patients. This diagnosis was confirmed by FNAB in 14 patients, 8 of whom did not undergo surgery and were simply followed up on a regular basis (Table II). In six of the nine remaining patients, correct diagnoses were obtained by FNAB. Two FNABs were nondiagnostic. One patient who was believed to have a malignant tumor on FNAB was found at surgery tohave a benign mixed tumor. A superficial parotidcctomy had been appropriately performed. None of the 22 patients in this group underwent inappropriate surgery as a result of the FNAB. In 10 patients, the diagnosis of malignancy was suspected on the basis of history and/or physical examination (Table III). In eight patients, the cytologic diagnosis of FNAB was correct, including one patient found to have sialadenitis who did not require surgery. Two incorrect diagnoses of salivary cancer were obtained by
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FNAB. One patient after further evaluation was found to have a metastatic small cell cancer from the lung. This patient did not undergo surgery. The other patient was found at surgery to have a benign mixed tumor with foci of carcinoma in situ. In this group, one patient did not undergo surgery as a result of FNAB, and no inappropriate procedures were performed due to errors on FNAB. Eleven patients were suspected clinically of having diseases of salivary lymphoid tissue rather than epithelial tumors. FNAB diagnoses were accurate in 10 of these patients, including 4 with lymphoma, 3 with reactive hyperplasia, and 2 with benign lymphoepithelial lesions. One patient was correctly discovered to have a benign salivary tumor. One error was made in a patient believed clinically and cytologically to have a benign lymphoepithelial lesion. Surgical biopsy eventually showed the diagnosis of lymphoma. In five patients with benign lymphoid tissue noted on FNAB, surgery was avoided entirely. The clinical impression in the remaining 17 cases ineluded 6 benign cysts, 1 lipoma, 1 hemangioma, and 9 patients in whom the diagnosis of sialadenitis was suspected. These were included in this series because the history and physical findings were not sufficiently diagnostic of sialadenitis to avoid the need for obtaining a tissue diagnosis. One of these nine patients was found by FNAB to have a Warthin's tumor that was removed. In two other patients, salivary tumors were suspected by FNAB. Surgery in these two patients confirmed the initial clinical impression of sialadenitis. Of the six patients thought clinically to have salivary cysts, one was found by FNAB to have a benign tumor that was removed and one had a Warthin's tumor that was observed. As a result of FNAB, surgery was avoided in 12 of these 17 patients. In the entire series of 101 patients, all of whom might have reasonably been considered candidates for salivary gland removal, surgery was avoided entirely in 27 (27%). Eight additional patients (8%) underwent lesser procedures than would have been recommended based on the initial clinical impression. In addition, in the groups of patients in whom observation might have been considered on clinical grounds (Warthin's tumor, lymphoid, miscellaneous), seven patients were identified in whom FNAB correctly indicated the need for surgery. In only three patients might inadequate surgery have been performed based on the results of FNAB. Two were the patients incorrectly diagnosed as having Warthin's tumors on FNAB who initially underwent enucleation of tumors that should have been treated by parotidectomy (benign mixed tumor, acinie cell carcinoma). The correct diagnosis was made in both cases by frozen section analysis, and their operations were converted immediately to appropriate superficial parotidectomies. The remaining patient was suspected by FNAB of having a benign lymphoepithelial lesion. Surgical biopsy was performed because of clinical f'mdings suggesting the presence of lymphoma, which was confirmed. None of the other errors on FNAB resulted in the performance of inadequate surgery.
TABLE I l l
Correlation of Cytologic and Final Diagnosis With Clinical ImpressionmMalignant Tumor FNAB Diagnosis
Final
Correct
Incorrect
Diagnosis
Malignant t u m o r Metastatic cancer Lymphoma Sialadenitis
4 2 1 1
2*,t ----
4 3 1 1 (1 observed)
Benign mixed t u m o r Total
-8
-2
1* 10
FNAB = fine needle aspiration biopsy. Correct final diagnosis in patient~ with incorrect FNAB diagnosis: *Benign mixed tumor with loci of carcinoma in situ, tMetastatic small cell carcinoma.
COlVlMENTS FNAB is not a new diagnostic technique. Spiro et al [10] describe the waning of the early enthusiasm for this technique at Memorial Hospital because of its relative inaccuracy. They reported a series of 144 FNABs performed from 1930 to 1968. Twenty-one percent of FNABs were nondiagnostie. False-negative benign diagnoses were obtained in 17%. For this reason and because it was thought that even accurate FNAB results rarely altered the course of treatment, FNAB of salivary masses was no longer commonly practiced at that institution. As recently as 1987, Olsen from the Mayo Clinic stated, "Fine-needle aspiration of these tumors is controversial. This technique rarely gives useful therapeutic information concerning a parotid lesion, and the rate of falsepositive and false-negative results is high. Generally, the presence of a persistent lump in the parotid region is an indication for removal" [9]. Recent studies of large numbers of patients have confirmed the accuracy of FNAB [1-8]. In most of these series, the overall accuracy rate exceeds 95%. The sensitivity for diagnosing benign tumors ranges from 88% to 98%, with a specificity of at least 94%. The sensitivity for detecting malignant tumors is somewhat lower, ranging from 58% to 96%, with a specificity of 71% to 88%. FNAB is not very accurate in differentiating among the various types of malignant tumors, with a specific accuracy of 27% to 85%. Among the common diagnostic problems are the difficulty in distinguishing benign oncocytic tumors from acinic cell carcinomas, monomorphic and pleomorphic adenomas from adenoid cystic carcinomas, low-grade mucoepidermoid carcinomas from Warthin's tumors, chronic sialadenitis, and retention cysts, and high-grade mucoepidermoid carcinomas from metastatic squamous carcinomas [12]. Complications of FNAB appear to be rare [1,5], although hematoma is occasionally reported [6]. Several authors have commented specifically on the absence of any reported cases of tumor implantation at the site of FNAB [2,5-7]. Several authors have suggested the usefulness of salivary FNAB in distinguishing tumors from non-neoplastic
THE AMERICAN JOURNAL OFSURGERY
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HELLER ET AL
conditions. Shaha et al [1] found FNAB valuable in avoiding parotidectomy or submandibular gland excision when the diagnosis of metastatic cancer, lymphoma, or sialadenitis was suggested. Incisional biopsy or observation is appropriate in these situations. In a report of 160 patients who underwent FNAB of salivary masses, Qizilbash et al [2] noted that, of 122 patients with benign diagnoses, 37% were found not to require surgery. O'Dwyer et al [7] noted the value of FNAB in distinguishing tumors of the submandibular salivary gland or tail of the parotid from enlarged lymph nodes in the submandibular or upper jugular regions. Frable and Frable [4] reported the results of FNAB of salivary masses in 552 patients. Of these, 340 were diagnosed on FNAB as having sialadenitis. FNAB in 12 of these patients resulted in a false-negative diagnosis, including 4 primary salivary malignancies, 3 metastatic squamous cell carcinomas, 3 benign salivary tumors, and 1 lymphoma. The majority of these results were believed to be sampling errors rather than incorrect cytologic evaluations. Rodriguez et al [5] also commented on the value of FNAB of salivary masses in distinguishing neoplastic from inflammatory disease, thus avoiding unnecessary surgery. They noted that the recognition of benign tumors, particularly Warthin's tumor, might permit the avoidance of surgery in patients who are a poor risk. On the other hand, the recognition of a malignant tumor preoperatively might permit planning of a more extensive surgical procedure if necessary. The sensitivity and specificity of FNAB in this series are slightly lower than those found in other series. This is probably due to our relative inexperience with FNAB of salivary masses early in this series. In addition, several of the malignant tumors that were incorrectly thought to be benign were low-grade tumors, which can be difficult to diagnose by FNAB [2,12]. The two tumors (aeinic cell carcinoma and benign mixed tumor) incorrectly diagnosed as Warthin's tumors on FNAB were the result of making this diagnosis based solely on the presence of characteristic epithelial cells without the presence of lymphoid cells. We no longer make the cytologic diagnosis of Warthin's tumor without both the characteristic epithelial and lymphoid cells being present. Despite these inaccuracies, in only three cases would the reliance solely on the results of FNAB have resulted in the performance of inappropriate surgery. In all three cases, appropriate surgery was performed based on frozen section analysis and clinical judgment. Warthin's tumors are reported separately from other
670
benign tumors in this series because of our belief that parotidectomy is generally not required for their treatment [11]. Unsuspected Warthin's tumors were identified in six patients. An additional seven patients who were thought to have Warthin's tumors on clinical grounds were correctly identified by FNAB as having other diagnoses. As with any diagnostic study, the results of FNAB must be interpreted in the context of the patient's history, physical examination, and subsequent course. Reliance on FNAB alone can result in inappropriate treatment decisions. This series of 101 patients confirms the suggestion in the reports cited above that FNAB of salivary masses provides useful information and permits modification or elimination of surgery in a substantial number of patients. In addition, it can be performed with a minimum of complications. For these reasons, FNAB should be part of the initial evaluation of most patients with major salivary gland masses.
REFERENCES 1. Shaha AR, Webbcr C, DiMaio T, Jaffe BM. Needle aspiration biopsy in salivary gland lesions. Am J Surg 1990; 160: 373-6. 2. Qizilbash All, Sianos J, Young JEM, Archibald SD. Fine needle aspiration biopsy cytology of major salivary glands. Acta Cytol 1985; 29: 503-12. 3. Layfidd L J, Tan P, Glasgow BJ. Fine, needle aspiration of salivary gland lesions. Arch Pathoi Lab Mod 1987; 111: 346-53. 4. Frable MAS, Frable WJ. Fine-needle aspiration biopsy of salivary glands. Laryngoscope 1991; 101: 245-9. 5. Rodriguez HP, Silver CE, Moisa II, Chacho MS. Fine, noodle aspiration of parotid tumors. Am J Surg 1989; 158: 342-4. 6. Nettle WJS, Ordl SR. Fine ne)-,.dleaspiration in the diagnosis of salivary gland lesions. Aust NZ J Surg 1989; 59: 47-51. 7. O'Dwyer P, Farrar WB, James AG, Finkr W, McCabc DP. Needle aspiration biopsy of major salivary gland tumors. Canccr 1986; 57: 554-7. 8. Pitts DB, Hilsinger RL, Karandy E, Ross JC, Caro JE. Fineneedle aspiration in the diagnosis of salivary gland disorders in the community hospital setting. Arch Otolaryngol Head Neck Surg 1992; 118: 479-82. 9. Kerry KD. The parotid lump--don't biopsy it. Postgrad Mcd 1987; 81: 225-34. lO. Spiro RH, Huvos AG, Strong EW. Cancer of the parotid gland. Am J Surg 1975; 130: 452-9. 11. Hdler KS, Attic JN. Treatment of Warthin's tumors by enueleafion. Am J Surg 1988; 156: 294-5. 12. Layfield LJ, Glasgow BJ. Diagnosis of salivary gland tumors by fine-needle aspiration cytology. Diagn Cytopathol 1991; 7: 267-72.
THE AMERICAN JOURNAL OF SURGERY VOLUME 164 DECEMBER 1992
The accuracy of fine needle aspiration biopsy (FNAB) in the diagnosis of salivary tumors has been well established. This study was undertaken to determine the impact of FNAB on patient management. One hundred one patients underwent FNAB of major salivary gland masses. The physician's initial clinical impression was compared with the FNAB diagnosis and the final diagnosis in each case. Forty patients had solitary masses thought to be benign tumors other than Warthin's tumors. FNAB in 13 of these patients (33%) yielded a diagnosis permitting modification of the planned procedure. The diagnosis of Warthin's tumor was suspected clinically in 23 patients. In nine of these patients ( 3 9 % ) , FNAB resulted in a different diagnosis. Of the 10 patients believed to have malignant tumors, using FNAB, 1 was found to have sialadenitis and 1 a lymphoma. Overall, FNAB resulted in a change in the clinical approach to 35% of the patients. We recomm e n d the performance of FNAB in almost all patients with salivary masses.
he accuracy of fine needle aspiration biopsy (FNAB) in the diagnosis of salivary tumors has been well T established [1--8]. Many surgeons, however, do not routinely perform this test on salivary gland masses because of the possibility of complications, the difficulty of distinguishing among various types of salivary tumors, or the assumption that the result of the FNAB will not change the management of the patient. Some authors strongly advise against FNAB of salivary gland masses [9,10]. The ultimate value of any diagnostic test is its ability to determine and perhaps modify the patient's further management. Not aH salivary gland masses require removal. Some benign parotid tumors or intraparotid lymph nodes can be removed without parotidectomy [1,11]. This study was designed not simply to confLrm the accuracy of FNAB of salivary gland masses but to determine its impact on patient management.
PATIENTS AND METHODS The medical records of all patients referred to the authors for evaluation of major salivary gland masses between June 1987 and December 1991 were reviewed. One hundred one patients were identified in whom FNAB was performed as part of their initial evaluation. Due to the individual preferences of the authors, not all patients underwent FNAB. Included in this series, however, is a group of 52 consecutive patients treated by 2 of the authors (KSH, SD), all of whom had FNAB. Patients in whom the diagnosis of sialadenitis was clinically obvious were not included in this study. FNAB was performed without local anesthesia by a free-hand technique, using a 10-mL syringe without a holder and a 22-gauge needle. A single skin puncture with multiple passes through the tumor while aspirating the syringe was performed. At least eight smears of each aspirate were prepared. Direct smears were immediately fixed in 95% ethanol and stained according to a standard Papanicolaou method. All smears were interpreted by a single cytopathologist (QC). Cytologic findings were characterized as benign if they were stated to be benign or if minimal atypia was described. They were considered malignant if so described in the report or if they were stated to be "suspicious for malignancy." Further management of the patient was based on the result of the FNAB in conjunction with the patient's history and physical findings. The hospital records of all patients who underwent further surgery of the salivary glands were reviewed, and the surgical pathologic findFromthe Headand NeckService,Departmentof Surgery,LongIsland ings were compared with the initial clinical impression JewishMedicalCenter,New HydePark,New York. before the results of the FNAB were obtained and with Requestsfor reprintsshouldbe addressedto KeithS. Heller,MD, the FNAB cytology report. Patients who did not undergo 200 MiddleneckRoad,Great Neck,New York 11021. Presentedat the ThirdInternationalConferenceon Headand Neck surgery were followed up with regular physical examinaCancer,San Francisco,California,July26-30, 1992. tions. In these patients, the diagnosis that was established THE AMERICANJOURNAL OF SURGERY VOLUME164 DECEMBER1992 667
HELLER ET AL
TABLE l
Correlation of Cytologic and Final Diagnosis With Clinical Impression--Benign T u m o r ( O t h e r Than Warthin's Tumor) FNAB Diagnosis Correct Incorrect Benign mixed tumor Warthin's tumor Malignant tumor Lymphoid (benign) Lymphoma Sialadenitis Cyst Benign spindle cell Benign (NOS) Nondiagnostic Hemangioma Lipoma Total
15 4 1 4 1 3 1 1 -4**,tt,**,w167 --34
1* 2t,$ 2$,w -1 ---It ---6
Final Diagnosis 17 4 (2 observed) 4 5 (3 observed) 1 4 (3 observed) 1 (observed) 2 (1 observed) __ -1 1 40
FNAB = fine needle aspiration biopsy; NOS = not otherwise specified. Correct final diagnosis of patients with indeterminate or incorrect FNAB diagnosis: *Adenoid cystic cancer. tAcinic ceil cancer. tBenign mixed tumor. w **Schwannoma. ttLympbadenitis. ~Lipoma. ~Hemangioma.
T A B L E II
Correlation of Cytologic and Final Diagnosis W i t h Clinical Impression--Warthin's Tumor FNAB Diagnosis Correct Incorrect Warthin's tumor Malignant tumor Cyst Lymphoid Lipoma Nondiagnostic Benign tumor Total
14 -2 3 1 2t,$ -22
-1" -----1
Final Diagnosis 14 (8 observed)
-2 (2 observed) 3 (1 observed) 1 1 2 23
FNAB = fine needle aspiration biopsy. Correct final diagnosis of patients with indeterminate or incorrect FNAB diagnosis: *Benign mixed tumor. tOncocytoma. tObse~ed,
by FNAB was assumed to be conf'm-ned if the clinical course was consistent with this diagnosis. All 101 patients were retrospectively classified into 5 groups (benign tumor other than Warthin's tumor, Warthin's tumor, malignant tumor, lymphoid, miscellaneous) based on the initial clinical diagnosis before the results of FNAB were obtained. The result of the FNAB and the final diagnosis for each patient in these groups are detailed in Tables k IL and IIL 668
T H E A M E R I C A N J O U R N A L OF SURGERY
Sensitivity is defined as the ratio of true-positive resuits to all masses conFmned to have a specific diagnosis. Specificity is defined as the ratio of correct final diagnoses to the number of cases with that diagnosis on FNAB. RESULTS A specific cytologic diagnosis was made in 95 of 101 FNABs that were performed (95%). Five percent of FNABs were nondiagnostic. In 12 patients, the result of the FNAB was incorrect (12%). The sensitivity of FNAB for the diagnosis of benign, non-Warthin's salivary tumors in this series is 90% and for malignant salivary tumors, excluding lymphoma, 63%. The specificity was 92% for benign tumors and 62% for malignant tumors. In 40 patients, the clinical diagnosis of a benign salivary tumor was made based on history and physical findhags. Patients in this category would normally be treated by superficial parotidectomy or submandibular dissection. Tumors thought to be Warthin's tumors based on their location, multifocality, and the age and sex of the patient were not included in this group. The diagnosis of benign, non-Warthin's salivary tumor was supported by FNAB in only 17 patients (Table I). In 13 patients (33%), either lesser surgery (excision of Warthin's tumors and lymph nodes) or no surgery (some Warthin's tumors, lymphadenitis, sialadenitis, and cysts) was possible. FNAB yielded incorrect diagnoses in 6 of these 40 patients (15%). Included were two patients with FNAB diagnoses of benign tumors that were found at surgery to be low-grade carcinomas, two patients thought to have Warthin's tumors, one of whom at surgery had an acmic cell cancer and the other a benign mixed tumor, and two patients with FNAB diagnoses of malignant tumors, one of whom was found to have a benign mixed tumor and the other sialadenids. Because the superficial parotidectomy or submandibular dissection rec~ommended for benign, non-Warthin's tumors would have been adequate for the malignant tumors, in only the two patients with a cytologic diagnosis of Warthin's tumor would reliance on the results of FNAB have resulted in inadequate surgery. The clinical diagnosis of Warthin's tumor was made in 23 patients. This diagnosis was confirmed by FNAB in 14 patients, 8 of whom did not undergo surgery and were simply followed up on a regular basis (Table II). In six of the nine remaining patients, correct diagnoses were obtained by FNAB. Two FNABs were nondiagnostic. One patient who was believed to have a malignant tumor on FNAB was found at surgery tohave a benign mixed tumor. A superficial parotidcctomy had been appropriately performed. None of the 22 patients in this group underwent inappropriate surgery as a result of the FNAB. In 10 patients, the diagnosis of malignancy was suspected on the basis of history and/or physical examination (Table III). In eight patients, the cytologic diagnosis of FNAB was correct, including one patient found to have sialadenitis who did not require surgery. Two incorrect diagnoses of salivary cancer were obtained by
VOLUME 164
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FINE NEEDLE ASPIRATION BIOPSY OF THE SALIVARY GLANDS
FNAB. One patient after further evaluation was found to have a metastatic small cell cancer from the lung. This patient did not undergo surgery. The other patient was found at surgery to have a benign mixed tumor with foci of carcinoma in situ. In this group, one patient did not undergo surgery as a result of FNAB, and no inappropriate procedures were performed due to errors on FNAB. Eleven patients were suspected clinically of having diseases of salivary lymphoid tissue rather than epithelial tumors. FNAB diagnoses were accurate in 10 of these patients, including 4 with lymphoma, 3 with reactive hyperplasia, and 2 with benign lymphoepithelial lesions. One patient was correctly discovered to have a benign salivary tumor. One error was made in a patient believed clinically and cytologically to have a benign lymphoepithelial lesion. Surgical biopsy eventually showed the diagnosis of lymphoma. In five patients with benign lymphoid tissue noted on FNAB, surgery was avoided entirely. The clinical impression in the remaining 17 cases ineluded 6 benign cysts, 1 lipoma, 1 hemangioma, and 9 patients in whom the diagnosis of sialadenitis was suspected. These were included in this series because the history and physical findings were not sufficiently diagnostic of sialadenitis to avoid the need for obtaining a tissue diagnosis. One of these nine patients was found by FNAB to have a Warthin's tumor that was removed. In two other patients, salivary tumors were suspected by FNAB. Surgery in these two patients confirmed the initial clinical impression of sialadenitis. Of the six patients thought clinically to have salivary cysts, one was found by FNAB to have a benign tumor that was removed and one had a Warthin's tumor that was observed. As a result of FNAB, surgery was avoided in 12 of these 17 patients. In the entire series of 101 patients, all of whom might have reasonably been considered candidates for salivary gland removal, surgery was avoided entirely in 27 (27%). Eight additional patients (8%) underwent lesser procedures than would have been recommended based on the initial clinical impression. In addition, in the groups of patients in whom observation might have been considered on clinical grounds (Warthin's tumor, lymphoid, miscellaneous), seven patients were identified in whom FNAB correctly indicated the need for surgery. In only three patients might inadequate surgery have been performed based on the results of FNAB. Two were the patients incorrectly diagnosed as having Warthin's tumors on FNAB who initially underwent enucleation of tumors that should have been treated by parotidectomy (benign mixed tumor, acinie cell carcinoma). The correct diagnosis was made in both cases by frozen section analysis, and their operations were converted immediately to appropriate superficial parotidectomies. The remaining patient was suspected by FNAB of having a benign lymphoepithelial lesion. Surgical biopsy was performed because of clinical f'mdings suggesting the presence of lymphoma, which was confirmed. None of the other errors on FNAB resulted in the performance of inadequate surgery.
TABLE I l l
Correlation of Cytologic and Final Diagnosis With Clinical ImpressionmMalignant Tumor FNAB Diagnosis
Final
Correct
Incorrect
Diagnosis
Malignant t u m o r Metastatic cancer Lymphoma Sialadenitis
4 2 1 1
2*,t ----
4 3 1 1 (1 observed)
Benign mixed t u m o r Total
-8
-2
1* 10
FNAB = fine needle aspiration biopsy. Correct final diagnosis in patient~ with incorrect FNAB diagnosis: *Benign mixed tumor with loci of carcinoma in situ, tMetastatic small cell carcinoma.
COlVlMENTS FNAB is not a new diagnostic technique. Spiro et al [10] describe the waning of the early enthusiasm for this technique at Memorial Hospital because of its relative inaccuracy. They reported a series of 144 FNABs performed from 1930 to 1968. Twenty-one percent of FNABs were nondiagnostie. False-negative benign diagnoses were obtained in 17%. For this reason and because it was thought that even accurate FNAB results rarely altered the course of treatment, FNAB of salivary masses was no longer commonly practiced at that institution. As recently as 1987, Olsen from the Mayo Clinic stated, "Fine-needle aspiration of these tumors is controversial. This technique rarely gives useful therapeutic information concerning a parotid lesion, and the rate of falsepositive and false-negative results is high. Generally, the presence of a persistent lump in the parotid region is an indication for removal" [9]. Recent studies of large numbers of patients have confirmed the accuracy of FNAB [1-8]. In most of these series, the overall accuracy rate exceeds 95%. The sensitivity for diagnosing benign tumors ranges from 88% to 98%, with a specificity of at least 94%. The sensitivity for detecting malignant tumors is somewhat lower, ranging from 58% to 96%, with a specificity of 71% to 88%. FNAB is not very accurate in differentiating among the various types of malignant tumors, with a specific accuracy of 27% to 85%. Among the common diagnostic problems are the difficulty in distinguishing benign oncocytic tumors from acinic cell carcinomas, monomorphic and pleomorphic adenomas from adenoid cystic carcinomas, low-grade mucoepidermoid carcinomas from Warthin's tumors, chronic sialadenitis, and retention cysts, and high-grade mucoepidermoid carcinomas from metastatic squamous carcinomas [12]. Complications of FNAB appear to be rare [1,5], although hematoma is occasionally reported [6]. Several authors have commented specifically on the absence of any reported cases of tumor implantation at the site of FNAB [2,5-7]. Several authors have suggested the usefulness of salivary FNAB in distinguishing tumors from non-neoplastic
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conditions. Shaha et al [1] found FNAB valuable in avoiding parotidectomy or submandibular gland excision when the diagnosis of metastatic cancer, lymphoma, or sialadenitis was suggested. Incisional biopsy or observation is appropriate in these situations. In a report of 160 patients who underwent FNAB of salivary masses, Qizilbash et al [2] noted that, of 122 patients with benign diagnoses, 37% were found not to require surgery. O'Dwyer et al [7] noted the value of FNAB in distinguishing tumors of the submandibular salivary gland or tail of the parotid from enlarged lymph nodes in the submandibular or upper jugular regions. Frable and Frable [4] reported the results of FNAB of salivary masses in 552 patients. Of these, 340 were diagnosed on FNAB as having sialadenitis. FNAB in 12 of these patients resulted in a false-negative diagnosis, including 4 primary salivary malignancies, 3 metastatic squamous cell carcinomas, 3 benign salivary tumors, and 1 lymphoma. The majority of these results were believed to be sampling errors rather than incorrect cytologic evaluations. Rodriguez et al [5] also commented on the value of FNAB of salivary masses in distinguishing neoplastic from inflammatory disease, thus avoiding unnecessary surgery. They noted that the recognition of benign tumors, particularly Warthin's tumor, might permit the avoidance of surgery in patients who are a poor risk. On the other hand, the recognition of a malignant tumor preoperatively might permit planning of a more extensive surgical procedure if necessary. The sensitivity and specificity of FNAB in this series are slightly lower than those found in other series. This is probably due to our relative inexperience with FNAB of salivary masses early in this series. In addition, several of the malignant tumors that were incorrectly thought to be benign were low-grade tumors, which can be difficult to diagnose by FNAB [2,12]. The two tumors (aeinic cell carcinoma and benign mixed tumor) incorrectly diagnosed as Warthin's tumors on FNAB were the result of making this diagnosis based solely on the presence of characteristic epithelial cells without the presence of lymphoid cells. We no longer make the cytologic diagnosis of Warthin's tumor without both the characteristic epithelial and lymphoid cells being present. Despite these inaccuracies, in only three cases would the reliance solely on the results of FNAB have resulted in the performance of inappropriate surgery. In all three cases, appropriate surgery was performed based on frozen section analysis and clinical judgment. Warthin's tumors are reported separately from other
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benign tumors in this series because of our belief that parotidectomy is generally not required for their treatment [11]. Unsuspected Warthin's tumors were identified in six patients. An additional seven patients who were thought to have Warthin's tumors on clinical grounds were correctly identified by FNAB as having other diagnoses. As with any diagnostic study, the results of FNAB must be interpreted in the context of the patient's history, physical examination, and subsequent course. Reliance on FNAB alone can result in inappropriate treatment decisions. This series of 101 patients confirms the suggestion in the reports cited above that FNAB of salivary masses provides useful information and permits modification or elimination of surgery in a substantial number of patients. In addition, it can be performed with a minimum of complications. For these reasons, FNAB should be part of the initial evaluation of most patients with major salivary gland masses.
REFERENCES 1. Shaha AR, Webbcr C, DiMaio T, Jaffe BM. Needle aspiration biopsy in salivary gland lesions. Am J Surg 1990; 160: 373-6. 2. Qizilbash All, Sianos J, Young JEM, Archibald SD. Fine needle aspiration biopsy cytology of major salivary glands. Acta Cytol 1985; 29: 503-12. 3. Layfidd L J, Tan P, Glasgow BJ. Fine, needle aspiration of salivary gland lesions. Arch Pathoi Lab Mod 1987; 111: 346-53. 4. Frable MAS, Frable WJ. Fine-needle aspiration biopsy of salivary glands. Laryngoscope 1991; 101: 245-9. 5. Rodriguez HP, Silver CE, Moisa II, Chacho MS. Fine, noodle aspiration of parotid tumors. Am J Surg 1989; 158: 342-4. 6. Nettle WJS, Ordl SR. Fine ne)-,.dleaspiration in the diagnosis of salivary gland lesions. Aust NZ J Surg 1989; 59: 47-51. 7. O'Dwyer P, Farrar WB, James AG, Finkr W, McCabc DP. Needle aspiration biopsy of major salivary gland tumors. Canccr 1986; 57: 554-7. 8. Pitts DB, Hilsinger RL, Karandy E, Ross JC, Caro JE. Fineneedle aspiration in the diagnosis of salivary gland disorders in the community hospital setting. Arch Otolaryngol Head Neck Surg 1992; 118: 479-82. 9. Kerry KD. The parotid lump--don't biopsy it. Postgrad Mcd 1987; 81: 225-34. lO. Spiro RH, Huvos AG, Strong EW. Cancer of the parotid gland. Am J Surg 1975; 130: 452-9. 11. Hdler KS, Attic JN. Treatment of Warthin's tumors by enueleafion. Am J Surg 1988; 156: 294-5. 12. Layfield LJ, Glasgow BJ. Diagnosis of salivary gland tumors by fine-needle aspiration cytology. Diagn Cytopathol 1991; 7: 267-72.
THE AMERICAN JOURNAL OF SURGERY VOLUME 164 DECEMBER 1992
