Br. J. Surg. 1990, Vol. 77, July, 756-758
A. 8 . S. Ball, C. Fisher*, M. Pittam, R. M. Watkins and G. Westbury Academic Surgical Unit and *Department of Histopathology, The Royal Marsden Hospital, London, UK Correspondence to: Mr A. B. S. Ball, Academic
Surgical Unit, Royal Marsden Hospital, Fulham Road, London SW3 6JJ, UK
Diagnosis of soft tissue tumours by Tru-Cut@biopsy Tru-Cut@biopsies were obtained from 52 consecutive patients referred with soft tissue tumours. Forty-five patients had soft tissue sarcomas; seven hadbenign soft tissue tumours. Ofthe biopsies 96per cent provided adequate material for diagnosis. The histological diagnosis made from the Tru-Cut biopsy was compared with that made from the resected specimen. There were no false positive diagnoses of malignancy. The accuracy of Tru-Cut biopsy was 98 per cent f o r the diagnosis of malignancy and 94 per cent for the diagnosis of sarcoma. Tumour subtype was correctly specified in 85 per cent of sarcomas and tumour grade in 88 per cent. Tru-Cut biopsy should replace open biopsy as the primary means of diagnosis of soft tissue tumours unless a satisfactory tissue sample cannot be obtained. Keywords: Soft tissue sarcoma, biopsy, Tru-Cut needle
Accurate histopathological diagnosis is important in the management of patients with soft tissue sarcoma'. It is frequently made from material obtained by open or excision biopsy, but such procedures are not wholly without complication^^.^. Needle biopsy is less traumatic, can be performed under local anaesthesia and is less likely to compromise definitive surgery. The technique has been criticized, however, because of problems in sampling and interpretation'. We have previously reported a study in which Tru-Cut'" (Travenol Laboratories Incorporated, Deerfield, Illinois, USA) biopsies were obtained from excised tumour specimens to minimize sampling errors. A correct diagnosis of soft tissue sarcoma was made in 87-98 per cent of cases4. In this paper we report the results of a subsequent study to determine the accuracy of Tru-Cut biopsy of tumours in situ.
Patients and methods The study group comprised 52 consecutive patients undergoing surgery for a soft tissue tumour at the Royal Marsden Hospital. The mean age of the patients was 45 years (range 12-80 years) and 29 were male. Of the tumours 39 were situated on the limbs and limb-girdles, eight were on the trunk, one was in the parotid region and four were retroperitoneal. A total of 34 patients were referred with clinical features of a primary soft tissue sarcoma in 11 of whom a pathological diagnosis of sarcoma had been established by open biopsy at the referring institution. In the remaining 18 patients the tumour represented locally recurrent disease in 17 and metastatic disease in one. Biopsies were obtained by percutaneous puncture after infiltration with 1 per cent lignocaine. A 14Ga Tru-Cut needle was used which provided a core of tissue whose maximum length was 20 mm. Two cores were usually obtained through the same puncture wound and the biopsy was repeated if a satisfactory core, as judged by simple inspection, was not obtained. The biopsy site was chosen so that it could be excised as part of the definitive procedure and, by examining relevant computed tomography scans, neurovascular structures and areas of cyst formation were avoided. In four patients with retroperitoneal tumours, biopsy was guided by computer assisted tomography or ultrasound. Biopsy cores were placed in formalin and prepared for histological examination. The slides were subsequently reviewed by one observer (C.F.), without knowledge of the clinical details, who was asked: (1) to categorize biopsies as malignant, benign, or inadequate for diagnosis; (2) to make a specific diagnosis where possible; and (3) to provide a histological grade for malignant tissue. The diagnosis was compared with the definitive report obtained by histological examination of the resected tumour. Immunohistochemical studies were undertaken on surgical specimens and occasionally on Tru-Cut samples.
Results The final histological diagnosis of excised specimens is shown in Table 1 . There were 45 malignant tumours and seven benign lesions. Malignant fibrous histiocytoma (MFH) accounted for 33 per cent of sarcomas. In 42 cases Tru-Cut biopsy was reported to show a malignant tumour and this was confirmed by definitive section in each case. Eight biopsies were reported as benign and this was confirmed by definitive histology in seven cases (i.e. there was one false negative diagnosis for malignancy). Two biopsy cores were considered inadequate for diagnosis. Of the 42 biopsies identified as malignant, 40 were specified as sarcoma and this was confirmed in each case. Two biopsies, though correctly diagnosed as malignant, were not identified as sarcoma and both were therefore counted as false negative diagnoses for sarcoma. Including the single false negative diagnosis for malignancy, there was a total of three false negative diagnoses for sarcoma. Excluding the two inadequate biopsies the predictive value of a positive Tru-Cut diagnosis for malignancy was 100 per cent, the sensitivity 98 per cent and the overall accuracy 98 per cent. For the diagnosis of sarcoma the predictive value of a positive diagnosis was 100 per cent, the sensitivity 93 per cent and the overall accuracy 94 per cent. Turnour subtype and grade Among 40 biopsies correctly diagnosed as sarcoma the tumour subtype was correctly specified in 34 (85 per cent), incorrectly specified in three (8 per cent) and impossible to specify in three
Table 1 Definitive diagnosis of 52 soft tissue turnours Malignant
No.
Nonmalignant
No.
Malignant fibrous histiocytoma Lipos a rcom a Malignant schwannoma Synovial sarcoma Pleomorphic sarcoma Leiomyosarcoma Rhabdomyosarcoma Triton tumour Chondrosarcoma Indeterminate Total
15 8 6 6 3 3 1
Fibroma tosis Lipoma
5 2
1
1 1 45
I
~
756
0007-1 323/90/07075&03
6 1990 Butterworth-Heinemann
Ltd
T r u - C u t biopsy o f s o f t t i s s u e t u r n o u r s : A. 6.S.Ball et al.
(8 per cent). Tumour grade was correctly specified in 35 biopsies (88 per cent), incorrectly specified in two (5 per cent) and impossible to specify in three (8 per cent). In the six cases in which tumour subtype was indeterminate or incorrectly specified, the grade was also indeterminate in one but correctly specified in five. The diagnosis of the seven benign lesions was correct in each case. Sources of’ error There was one false negative diagnosis of malignancy where the biopsy was interpreted as a benign lipoma. Definitive section revealed a lipoma-like (well differentiated) liposarcoma. In two cases a diagnosis of malignancy was made but categorization was impossible. One was an extensively necrotic, poorly differentiated myxoid liposarcoma; the other was a focally necrotic MFH. In three cases correctly identified as sarcoma the subtype was wrongly specified. Two were cases of pleomorphic MFH, which were incorrectly specified as liposarcoma and malignant peripheral nerve sheath tumour. One case was a pleomorphic leiomyosarcoma, which was incorrectly specified as a pleomorphic MFH. In three cases identified as sarcoma the subtype could not be specified; two were cases of pleomorphic MFH and one was an extensively necrotic malignant Triton tumour. Tumour grade was incorrectly specified in two peripheral nerve sheath tumours and impossible to specify in three necrotic tumours. Complications
There were no complications from Tru-Cut biopsy among patients with soft tissue tumours of the limbs. One patient with a retroperitoneal tumour developed signs of intra-abdominal bleeding following Tru-Cut biopsy and required blood transfusion.
Discussion Biopsy is a prerequisite in the management of patients with soft tissue tumours. A confident distinction between benign and malignant lesions cannot always be made by physical examination alone and the biological behaviour of malignant soft tissue tumours is closely related to the histological grade and tumour subtype’. Open biopsy requires general anaesthesia and surgical complications are reported to occur in up to 20 per cent of cases3. In contrast, closed biopsy is simple to perform under local anaesthesia and wound complications are exceptional one complication in the present study in a patient with a retroperitoneal tumour. Closed biopsy can be carried out with a Tru-Cut needle or by fine needle aspiration. We have previously evaluated both techniques using the excised specimen to minimize sampling errors4+’.Tru-Cut biopsy proved to be more accurate in these circumstances. In patients with suspected soft tissue sarcoma, biopsy, whether open or closed, must be planned carefully. To avoid tumour implantation the biopsy site should be excised en bloc with the primary lesion’. This may not be easy after open biopsy, particularly if the incision has been poorly orientated’. After Tru-Cut biopsy the wound can be readily incorporated in the definitive resection and the risk of needle-track implantation is thereby eliminated. Needle biopsy has been criticized principally because the quantity of biopsy material may be insufficient for accurate diagnosis2. In the present study, however, only 4 per cent of biopsies were considered to be inadequate. Unsuitable samples were kept to a minimum by repeating the biopsy if the sample appeared unsatisfactory on simple inspection and by examining relevant computed tomography scans before selecting the
Br. J. S u r g . , Vol. 77, No. 7 , J u l y 1990
biopsy site so that cystic areas could be avoided. In most cases two biopsy cores were obtained from the tumour. The overall accuracy for diagnosis of malignancy was 98 per cent and a diagnosis of sarcoma was specified with an accuracy of 94 per cent. Tru-Cut biopsies were examined by a pathologist (C.F.) with considerable experience in the diagnosis of soft tissue tumours and this undoubtedly contributed to the level of accuracy achieved. This study and its predecessor4 demonstrate that a reliable diagnosis of soft tissue sarcoma can be made from the relatively small quantity of tissue obtained by Tru-Cut biopsy. If histological interpretation proves difficult, slides can be sent for review by a pathologist with a specific interest in soft tissue tumours. Paradoxically, Tru-Cut biopsy may provide a more representative tissue sample than open biopsy. At open biopsy, unless a trocar is used6, tissue is often taken from the surface of the tumour which typically consists of a well developed pseudocapsule. With a Tru-Cut needle tissue is obtained from within the main bulk of tumour and this may explain why the accuracy compares so favourably with that of open biopsy3. The only false negative diagnosis of malignancy was made in a patient with a low grade (lipoma-like) liposarcoma. This tumour can be almost indistinguishable from a benign lipoma even when the entire specimen is available for formal examination’. There were no false positive diagnoses of malignancy. As a result of referral practices, however, there was a total of only seven benign lesions. The specificity of Tru-Cut biopsy cannot therefore be assured. This is important because amputation is occasionally necessary to treat malignant soft tissue tumours of the extremities and a false positive diagnosis could therefore have disastrous consequences. In practice, amputation is seldom undertaken in our unit except as a salvage procedure after failed conservative surgery’ and a definitive diagnosis is already established. If amputation is contemplated as a primary procedure and the result of Tru-Cut biopsy is in any way equivocal, there should be no hesitation in resorting to open biopsy, preferably using the technique of punch biopsy described elsewhere6. Histological subtype was correctly specified in 85 per cent of biopsies identified as sarcoma. An extremely pleomorphic appearance or extensive necrosis were the main reasons for inaccurate classification. Tumour grade was correctly specified in 88 per cent of biopsies identified as sarcoma and in all but one of those in which the subtype was indeterminate or incorrectly specified. Both incorrectly graded biopsies were from peripheral nerve sheath tumours whose behaviour does not necessarily correspond to the degree of differentiation’. Tru-Cut is as accurate as conventional open biopsy for the diagnosis of soft tissue sarcoma. Since it is simpler to perform, less expensive, almost free from complications and unlikely to compromise subsequent management we recommend that it should be used in place of open biopsy. At the Royal Marsden Hospital it is now our practice to encourage clinicians seeking advice on the management of suspected soft tissue tumours to perform a Tru-Cut biopsy and send slides of the material obtained to our pathologist for review.
References I. 2. 3. 4. 5.
Enzinger F M , Weiss SW. Sofi Tissue Tumours. 2nd ed. St. Louis, Missouri: CV Mosby, 1988: 3-5. Simon MA. Biopsy of musculoskeletal tumors. J Bone Joinr Surg (Ant) 1982; 64:1253-7. Mankin HJ, Lange TA, Spanier SS. The hazards of biopsy in patients with primary bone and soft tissue tumors, J Eot7e Joit7r Surg ( A m ) 1982; 64: 1121-7. Kissin MW. Fisher C, Carter RL, Horton LWL, Westbury G. Value of Tru-Cut biopsy in the diagnosis of soft tissue turnours. Er J Surg 1986; 73: 7 4 2 4 . Kissin MW, Fisher C, Webb AJ, Westbury G. Value offine needle aspiration cytology in the diagnosis of soft tissue turnours: a preliminary study on the excised specimen. Er J Surg 1987; 74: 479-80.
757
Tru-Cut biopsy of soft tissue tumours: A. B. S. Ball e t al.
6. 7.
8.
Westbury G . Soft tissue sarcomas. In: Keen G, ed. Operative Surgery and Managemeni. Bristol: Wright, 1987: 758. Enzinger FM, Weiss SW. Soji Tissue Tumours. 2nd ed. St. Louis, Missouri: CV Mosby, 1988: 363. Westbury G . Surgery of soft tissue sarcomas. In: Pinedo, HM, Verweij J , eds. Treaiment qfSqft Tissue Sarcomas. Boston: Kluwer
9.
Academic Publishers, 1989: 60. Fisher C. Pathology of soft tissue sarcomas. In: Pinedo HM, Verweij J, eds. Treatment ofSofi Tissue Sarcomas. Boston: Kluwer Academic Publishers, 1989: 13.
Paper accepted 10 January 1990
Case report Br. J. Surg. 1990, Vol. 77, July, 758-759
Massive haemorrhage following endoscopic transgastric drainage of pancreatic pseudocyst P. K. Donnelly, J. Lavelle* and D. Carr-Locket Departments of Surgery, *Radiology, f Medicine and f Gastroenterology, Leicester Teaching Hospitals, Leicester,
UK Correspondence to: Mr P. K. Donnelly, Department of Surgery, Leicester General Hospital, Gwendolen Road, Leicester LE5 4PW. UK
Pancreatic pseudocysts occur in up to 15 per cent of patients following acute pancreatitis’ . While spontaneous resolution occurs in the minority of cases after 4-6 weeks’, the conventional surgical management of established cysts is operative drainage through the posterior gastric wall. The introduction of sensitive diagnostic techniques such as ultrasound, endoscopic retrograde cholangiopancreatography (ERCP) and computed tomographic scanning, have facilitated .~. the development of percutaneous cyst d ~ - a i n a g e ~Recent reports document the drainage of pseudocysts using an e n d o ~ c o p e ~Endoscopic +~. electrocautery can be used to cut into a pseudocyst as it bulges into the gastric lumen5. A straight catheter can be placed through the wall to achieve limited internal drainage. Bleeding has been a theoretical risk. We report a case of endoscopic drainage of a pseudocyst which resulted in immediat,, inassive, life-threatening haemorrhage.
gradually improved but she was noted to have an epigastric mass. Computed tomograpic scanning showed an oedematous pancreas with evidence of an inflammatory collection over the midbody, which was confirmed as a pseudocyst on aspiration cytology. As her condition stabilized supportive therapy was continued. Two weeks later repeat ultrasound and computed tomographic scanning showed a very large pancreatic pseudocyst (Figure I ) compressing the posterior wall of the stomach. As she was intermittently pyrexial with an unresolved pseudocyst after 5 weeks of observation, it was felt that an attempt at endoscopic cyst drainage was appropriate to avoid surgical intervention in an immunocompromised patient. An ERCP, performed by an experienced gastroenterologist, demonstrated a patent pancreatic duct which was 3 m m wide but narrowed in the body and freely communicating with the pancreatic pseudocyst (Figure 2). It was not considered possible to drain this by a stent across the papilla. With the patient sedated and using an end-viewing fibreoptic endoscope, the stomach was visualized and a large bulge identified on the lesser curve. At the apex of the bulge a cautery needle was used to penetrate the mucosa and a jet of turbid fluid was released from the cyst. The heated wire was replaced with a ‘sphincterotomy’ wire which was used to enlarge the puncture site to 1 crn to improve the cyst drainage. This manoeuvre was followed by brisk arterial haemorrhage from the cyst wall. The patient developed tachycardia and was immediately transferred to theatre where laparotomy showed 2 I of blood in the stomach. She required a total of 8 units of blood transfusion. The right gastric artery was bleeding briskly in the edge of the thickened cyst wall. The vessel was oversewn and haemostasis achieved. The cyst cavity which extended around the renal vessels inferiorly was empty and was irrigated. The cystgastrostomy was enlarged and the free edges oversewn for haemostasis. The gallbladder, which contained multiple stones, was also removed. Following surgery she made an uneventful recovery and 3 months later is well with normal renal function, no evidence of pancreatic exocrine or endocrine insufficiency and no evidence on ultrasound of recurrent pseudocyst formation.
Discussion While minimally invasive procedures are becoming attractive options, particularly when dealing with high risk patients, they
Case report A 50-year-old Asian woman was admitted as an emergency with a 24-h history of severe upper abdominal pain. She was known to suffer from end stage renal failure for which she had successfully undergone renal transplantation 16 months earlier. Up to the time of her admission renal function was excellent with a creatinine level of 80mmol/l while on maintenance immunosuppressive therapy of 4 mg/kg of cyclosporin and 5 mg/day of prednisolone. She had a history of intermittent flatulent dyspepsia and right upper quadrant pain. On examination she was distressed but apyrexial, and had tenderness and guarding in the epigastrium. She had leucocytosis and amylasaemia of 16241 units per litre, consistent with acute pancreatitis. Upper abdominal ultrasound demonstrated a distended gallbladder containing multiple small stones. The pancreas was diffusely swollen and the biliary tree was normal, as were her liver function tests. Computed tomographic scanning showed changes consistent with necrosis in the midbody of the pancreas with no evidence of fluid collection. She was treated conservatively with nasogastric suction, total parenteral nutrition and antibiotics. Her condition deteriorated, she became pyrexial, hypoxic and required observation in the intensive therapy unit. After 1 week her condition
Figure 1 A very large pseudocyst shown on computed tomographic scanning to have replaced most of the pancreas
758
0007- 1323/90/070758-02
~
-~
63 1990 Butterworth Heinemann Ltd
A. 8 . S. Ball, C. Fisher*, M. Pittam, R. M. Watkins and G. Westbury Academic Surgical Unit and *Department of Histopathology, The Royal Marsden Hospital, London, UK Correspondence to: Mr A. B. S. Ball, Academic
Surgical Unit, Royal Marsden Hospital, Fulham Road, London SW3 6JJ, UK
Diagnosis of soft tissue tumours by Tru-Cut@biopsy Tru-Cut@biopsies were obtained from 52 consecutive patients referred with soft tissue tumours. Forty-five patients had soft tissue sarcomas; seven hadbenign soft tissue tumours. Ofthe biopsies 96per cent provided adequate material for diagnosis. The histological diagnosis made from the Tru-Cut biopsy was compared with that made from the resected specimen. There were no false positive diagnoses of malignancy. The accuracy of Tru-Cut biopsy was 98 per cent f o r the diagnosis of malignancy and 94 per cent for the diagnosis of sarcoma. Tumour subtype was correctly specified in 85 per cent of sarcomas and tumour grade in 88 per cent. Tru-Cut biopsy should replace open biopsy as the primary means of diagnosis of soft tissue tumours unless a satisfactory tissue sample cannot be obtained. Keywords: Soft tissue sarcoma, biopsy, Tru-Cut needle
Accurate histopathological diagnosis is important in the management of patients with soft tissue sarcoma'. It is frequently made from material obtained by open or excision biopsy, but such procedures are not wholly without complication^^.^. Needle biopsy is less traumatic, can be performed under local anaesthesia and is less likely to compromise definitive surgery. The technique has been criticized, however, because of problems in sampling and interpretation'. We have previously reported a study in which Tru-Cut'" (Travenol Laboratories Incorporated, Deerfield, Illinois, USA) biopsies were obtained from excised tumour specimens to minimize sampling errors. A correct diagnosis of soft tissue sarcoma was made in 87-98 per cent of cases4. In this paper we report the results of a subsequent study to determine the accuracy of Tru-Cut biopsy of tumours in situ.
Patients and methods The study group comprised 52 consecutive patients undergoing surgery for a soft tissue tumour at the Royal Marsden Hospital. The mean age of the patients was 45 years (range 12-80 years) and 29 were male. Of the tumours 39 were situated on the limbs and limb-girdles, eight were on the trunk, one was in the parotid region and four were retroperitoneal. A total of 34 patients were referred with clinical features of a primary soft tissue sarcoma in 11 of whom a pathological diagnosis of sarcoma had been established by open biopsy at the referring institution. In the remaining 18 patients the tumour represented locally recurrent disease in 17 and metastatic disease in one. Biopsies were obtained by percutaneous puncture after infiltration with 1 per cent lignocaine. A 14Ga Tru-Cut needle was used which provided a core of tissue whose maximum length was 20 mm. Two cores were usually obtained through the same puncture wound and the biopsy was repeated if a satisfactory core, as judged by simple inspection, was not obtained. The biopsy site was chosen so that it could be excised as part of the definitive procedure and, by examining relevant computed tomography scans, neurovascular structures and areas of cyst formation were avoided. In four patients with retroperitoneal tumours, biopsy was guided by computer assisted tomography or ultrasound. Biopsy cores were placed in formalin and prepared for histological examination. The slides were subsequently reviewed by one observer (C.F.), without knowledge of the clinical details, who was asked: (1) to categorize biopsies as malignant, benign, or inadequate for diagnosis; (2) to make a specific diagnosis where possible; and (3) to provide a histological grade for malignant tissue. The diagnosis was compared with the definitive report obtained by histological examination of the resected tumour. Immunohistochemical studies were undertaken on surgical specimens and occasionally on Tru-Cut samples.
Results The final histological diagnosis of excised specimens is shown in Table 1 . There were 45 malignant tumours and seven benign lesions. Malignant fibrous histiocytoma (MFH) accounted for 33 per cent of sarcomas. In 42 cases Tru-Cut biopsy was reported to show a malignant tumour and this was confirmed by definitive section in each case. Eight biopsies were reported as benign and this was confirmed by definitive histology in seven cases (i.e. there was one false negative diagnosis for malignancy). Two biopsy cores were considered inadequate for diagnosis. Of the 42 biopsies identified as malignant, 40 were specified as sarcoma and this was confirmed in each case. Two biopsies, though correctly diagnosed as malignant, were not identified as sarcoma and both were therefore counted as false negative diagnoses for sarcoma. Including the single false negative diagnosis for malignancy, there was a total of three false negative diagnoses for sarcoma. Excluding the two inadequate biopsies the predictive value of a positive Tru-Cut diagnosis for malignancy was 100 per cent, the sensitivity 98 per cent and the overall accuracy 98 per cent. For the diagnosis of sarcoma the predictive value of a positive diagnosis was 100 per cent, the sensitivity 93 per cent and the overall accuracy 94 per cent. Turnour subtype and grade Among 40 biopsies correctly diagnosed as sarcoma the tumour subtype was correctly specified in 34 (85 per cent), incorrectly specified in three (8 per cent) and impossible to specify in three
Table 1 Definitive diagnosis of 52 soft tissue turnours Malignant
No.
Nonmalignant
No.
Malignant fibrous histiocytoma Lipos a rcom a Malignant schwannoma Synovial sarcoma Pleomorphic sarcoma Leiomyosarcoma Rhabdomyosarcoma Triton tumour Chondrosarcoma Indeterminate Total
15 8 6 6 3 3 1
Fibroma tosis Lipoma
5 2
1
1 1 45
I
~
756
0007-1 323/90/07075&03
6 1990 Butterworth-Heinemann
Ltd
T r u - C u t biopsy o f s o f t t i s s u e t u r n o u r s : A. 6.S.Ball et al.
(8 per cent). Tumour grade was correctly specified in 35 biopsies (88 per cent), incorrectly specified in two (5 per cent) and impossible to specify in three (8 per cent). In the six cases in which tumour subtype was indeterminate or incorrectly specified, the grade was also indeterminate in one but correctly specified in five. The diagnosis of the seven benign lesions was correct in each case. Sources of’ error There was one false negative diagnosis of malignancy where the biopsy was interpreted as a benign lipoma. Definitive section revealed a lipoma-like (well differentiated) liposarcoma. In two cases a diagnosis of malignancy was made but categorization was impossible. One was an extensively necrotic, poorly differentiated myxoid liposarcoma; the other was a focally necrotic MFH. In three cases correctly identified as sarcoma the subtype was wrongly specified. Two were cases of pleomorphic MFH, which were incorrectly specified as liposarcoma and malignant peripheral nerve sheath tumour. One case was a pleomorphic leiomyosarcoma, which was incorrectly specified as a pleomorphic MFH. In three cases identified as sarcoma the subtype could not be specified; two were cases of pleomorphic MFH and one was an extensively necrotic malignant Triton tumour. Tumour grade was incorrectly specified in two peripheral nerve sheath tumours and impossible to specify in three necrotic tumours. Complications
There were no complications from Tru-Cut biopsy among patients with soft tissue tumours of the limbs. One patient with a retroperitoneal tumour developed signs of intra-abdominal bleeding following Tru-Cut biopsy and required blood transfusion.
Discussion Biopsy is a prerequisite in the management of patients with soft tissue tumours. A confident distinction between benign and malignant lesions cannot always be made by physical examination alone and the biological behaviour of malignant soft tissue tumours is closely related to the histological grade and tumour subtype’. Open biopsy requires general anaesthesia and surgical complications are reported to occur in up to 20 per cent of cases3. In contrast, closed biopsy is simple to perform under local anaesthesia and wound complications are exceptional one complication in the present study in a patient with a retroperitoneal tumour. Closed biopsy can be carried out with a Tru-Cut needle or by fine needle aspiration. We have previously evaluated both techniques using the excised specimen to minimize sampling errors4+’.Tru-Cut biopsy proved to be more accurate in these circumstances. In patients with suspected soft tissue sarcoma, biopsy, whether open or closed, must be planned carefully. To avoid tumour implantation the biopsy site should be excised en bloc with the primary lesion’. This may not be easy after open biopsy, particularly if the incision has been poorly orientated’. After Tru-Cut biopsy the wound can be readily incorporated in the definitive resection and the risk of needle-track implantation is thereby eliminated. Needle biopsy has been criticized principally because the quantity of biopsy material may be insufficient for accurate diagnosis2. In the present study, however, only 4 per cent of biopsies were considered to be inadequate. Unsuitable samples were kept to a minimum by repeating the biopsy if the sample appeared unsatisfactory on simple inspection and by examining relevant computed tomography scans before selecting the
Br. J. S u r g . , Vol. 77, No. 7 , J u l y 1990
biopsy site so that cystic areas could be avoided. In most cases two biopsy cores were obtained from the tumour. The overall accuracy for diagnosis of malignancy was 98 per cent and a diagnosis of sarcoma was specified with an accuracy of 94 per cent. Tru-Cut biopsies were examined by a pathologist (C.F.) with considerable experience in the diagnosis of soft tissue tumours and this undoubtedly contributed to the level of accuracy achieved. This study and its predecessor4 demonstrate that a reliable diagnosis of soft tissue sarcoma can be made from the relatively small quantity of tissue obtained by Tru-Cut biopsy. If histological interpretation proves difficult, slides can be sent for review by a pathologist with a specific interest in soft tissue tumours. Paradoxically, Tru-Cut biopsy may provide a more representative tissue sample than open biopsy. At open biopsy, unless a trocar is used6, tissue is often taken from the surface of the tumour which typically consists of a well developed pseudocapsule. With a Tru-Cut needle tissue is obtained from within the main bulk of tumour and this may explain why the accuracy compares so favourably with that of open biopsy3. The only false negative diagnosis of malignancy was made in a patient with a low grade (lipoma-like) liposarcoma. This tumour can be almost indistinguishable from a benign lipoma even when the entire specimen is available for formal examination’. There were no false positive diagnoses of malignancy. As a result of referral practices, however, there was a total of only seven benign lesions. The specificity of Tru-Cut biopsy cannot therefore be assured. This is important because amputation is occasionally necessary to treat malignant soft tissue tumours of the extremities and a false positive diagnosis could therefore have disastrous consequences. In practice, amputation is seldom undertaken in our unit except as a salvage procedure after failed conservative surgery’ and a definitive diagnosis is already established. If amputation is contemplated as a primary procedure and the result of Tru-Cut biopsy is in any way equivocal, there should be no hesitation in resorting to open biopsy, preferably using the technique of punch biopsy described elsewhere6. Histological subtype was correctly specified in 85 per cent of biopsies identified as sarcoma. An extremely pleomorphic appearance or extensive necrosis were the main reasons for inaccurate classification. Tumour grade was correctly specified in 88 per cent of biopsies identified as sarcoma and in all but one of those in which the subtype was indeterminate or incorrectly specified. Both incorrectly graded biopsies were from peripheral nerve sheath tumours whose behaviour does not necessarily correspond to the degree of differentiation’. Tru-Cut is as accurate as conventional open biopsy for the diagnosis of soft tissue sarcoma. Since it is simpler to perform, less expensive, almost free from complications and unlikely to compromise subsequent management we recommend that it should be used in place of open biopsy. At the Royal Marsden Hospital it is now our practice to encourage clinicians seeking advice on the management of suspected soft tissue tumours to perform a Tru-Cut biopsy and send slides of the material obtained to our pathologist for review.
References I. 2. 3. 4. 5.
Enzinger F M , Weiss SW. Sofi Tissue Tumours. 2nd ed. St. Louis, Missouri: CV Mosby, 1988: 3-5. Simon MA. Biopsy of musculoskeletal tumors. J Bone Joinr Surg (Ant) 1982; 64:1253-7. Mankin HJ, Lange TA, Spanier SS. The hazards of biopsy in patients with primary bone and soft tissue tumors, J Eot7e Joit7r Surg ( A m ) 1982; 64: 1121-7. Kissin MW. Fisher C, Carter RL, Horton LWL, Westbury G. Value of Tru-Cut biopsy in the diagnosis of soft tissue turnours. Er J Surg 1986; 73: 7 4 2 4 . Kissin MW, Fisher C, Webb AJ, Westbury G. Value offine needle aspiration cytology in the diagnosis of soft tissue turnours: a preliminary study on the excised specimen. Er J Surg 1987; 74: 479-80.
757
Tru-Cut biopsy of soft tissue tumours: A. B. S. Ball e t al.
6. 7.
8.
Westbury G . Soft tissue sarcomas. In: Keen G, ed. Operative Surgery and Managemeni. Bristol: Wright, 1987: 758. Enzinger FM, Weiss SW. Soji Tissue Tumours. 2nd ed. St. Louis, Missouri: CV Mosby, 1988: 363. Westbury G . Surgery of soft tissue sarcomas. In: Pinedo, HM, Verweij J , eds. Treaiment qfSqft Tissue Sarcomas. Boston: Kluwer
9.
Academic Publishers, 1989: 60. Fisher C. Pathology of soft tissue sarcomas. In: Pinedo HM, Verweij J, eds. Treatment ofSofi Tissue Sarcomas. Boston: Kluwer Academic Publishers, 1989: 13.
Paper accepted 10 January 1990
Case report Br. J. Surg. 1990, Vol. 77, July, 758-759
Massive haemorrhage following endoscopic transgastric drainage of pancreatic pseudocyst P. K. Donnelly, J. Lavelle* and D. Carr-Locket Departments of Surgery, *Radiology, f Medicine and f Gastroenterology, Leicester Teaching Hospitals, Leicester,
UK Correspondence to: Mr P. K. Donnelly, Department of Surgery, Leicester General Hospital, Gwendolen Road, Leicester LE5 4PW. UK
Pancreatic pseudocysts occur in up to 15 per cent of patients following acute pancreatitis’ . While spontaneous resolution occurs in the minority of cases after 4-6 weeks’, the conventional surgical management of established cysts is operative drainage through the posterior gastric wall. The introduction of sensitive diagnostic techniques such as ultrasound, endoscopic retrograde cholangiopancreatography (ERCP) and computed tomographic scanning, have facilitated .~. the development of percutaneous cyst d ~ - a i n a g e ~Recent reports document the drainage of pseudocysts using an e n d o ~ c o p e ~Endoscopic +~. electrocautery can be used to cut into a pseudocyst as it bulges into the gastric lumen5. A straight catheter can be placed through the wall to achieve limited internal drainage. Bleeding has been a theoretical risk. We report a case of endoscopic drainage of a pseudocyst which resulted in immediat,, inassive, life-threatening haemorrhage.
gradually improved but she was noted to have an epigastric mass. Computed tomograpic scanning showed an oedematous pancreas with evidence of an inflammatory collection over the midbody, which was confirmed as a pseudocyst on aspiration cytology. As her condition stabilized supportive therapy was continued. Two weeks later repeat ultrasound and computed tomographic scanning showed a very large pancreatic pseudocyst (Figure I ) compressing the posterior wall of the stomach. As she was intermittently pyrexial with an unresolved pseudocyst after 5 weeks of observation, it was felt that an attempt at endoscopic cyst drainage was appropriate to avoid surgical intervention in an immunocompromised patient. An ERCP, performed by an experienced gastroenterologist, demonstrated a patent pancreatic duct which was 3 m m wide but narrowed in the body and freely communicating with the pancreatic pseudocyst (Figure 2). It was not considered possible to drain this by a stent across the papilla. With the patient sedated and using an end-viewing fibreoptic endoscope, the stomach was visualized and a large bulge identified on the lesser curve. At the apex of the bulge a cautery needle was used to penetrate the mucosa and a jet of turbid fluid was released from the cyst. The heated wire was replaced with a ‘sphincterotomy’ wire which was used to enlarge the puncture site to 1 crn to improve the cyst drainage. This manoeuvre was followed by brisk arterial haemorrhage from the cyst wall. The patient developed tachycardia and was immediately transferred to theatre where laparotomy showed 2 I of blood in the stomach. She required a total of 8 units of blood transfusion. The right gastric artery was bleeding briskly in the edge of the thickened cyst wall. The vessel was oversewn and haemostasis achieved. The cyst cavity which extended around the renal vessels inferiorly was empty and was irrigated. The cystgastrostomy was enlarged and the free edges oversewn for haemostasis. The gallbladder, which contained multiple stones, was also removed. Following surgery she made an uneventful recovery and 3 months later is well with normal renal function, no evidence of pancreatic exocrine or endocrine insufficiency and no evidence on ultrasound of recurrent pseudocyst formation.
Discussion While minimally invasive procedures are becoming attractive options, particularly when dealing with high risk patients, they
Case report A 50-year-old Asian woman was admitted as an emergency with a 24-h history of severe upper abdominal pain. She was known to suffer from end stage renal failure for which she had successfully undergone renal transplantation 16 months earlier. Up to the time of her admission renal function was excellent with a creatinine level of 80mmol/l while on maintenance immunosuppressive therapy of 4 mg/kg of cyclosporin and 5 mg/day of prednisolone. She had a history of intermittent flatulent dyspepsia and right upper quadrant pain. On examination she was distressed but apyrexial, and had tenderness and guarding in the epigastrium. She had leucocytosis and amylasaemia of 16241 units per litre, consistent with acute pancreatitis. Upper abdominal ultrasound demonstrated a distended gallbladder containing multiple small stones. The pancreas was diffusely swollen and the biliary tree was normal, as were her liver function tests. Computed tomographic scanning showed changes consistent with necrosis in the midbody of the pancreas with no evidence of fluid collection. She was treated conservatively with nasogastric suction, total parenteral nutrition and antibiotics. Her condition deteriorated, she became pyrexial, hypoxic and required observation in the intensive therapy unit. After 1 week her condition
Figure 1 A very large pseudocyst shown on computed tomographic scanning to have replaced most of the pancreas
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63 1990 Butterworth Heinemann Ltd
