SCIENTIFIC
PAPERS
Technical Considerations for Prophylactic Mastectomy in Patients at High Risk for Breast Cancer Walley J. Temple,
MD,
Robert L. Lindsay,
MD,
Enzio Magi,
A study of 5 patients and 10 mastectomy specimens was performed to identify the extent of surgery necessary to completely remove all breast tissue in patients having prophylactic mastectomies. A standard total mastectomy performed for breast cancer was shown to frequently leave breast tissue within the superficial pectoralis major muscle and the lower skin flap. Frozen section analysis of margins was found to be essential to clear the axillary extension of the breast and lower skin flap in particular. The value of more extensive surgery to remove all glandular elements of the breast in the high-risk patient remains to be demonstrated.
he controversy concerning the extent of prophylactic mastectomy needed for high-risk patients to reduce T the risk of breast cancer developing remains unresolved [I]. The most common procedure done for this indication is the subcutaneous mastectomy. This leaves behind a substantial amount of glandular tissue in the tail of the breast, beneath the nipple, and in the relatively thick skin flaps that are developed. It has been estimated that 5% of the breast tissue remains after such operations. This type of procedure gives a much better cosmetic result but has been associated with an incidence of at least 1% breast cancer in anecdotal reports of fairly short follow-up. For this reason, a number of surgeons believe that a total mastectomy is theoretically a superior operation to a subcutaneous mastectomy [2,3]. However, no well-done study has been completed that establishes the adequacy of a total mastectomy procedure to determine if a total mastectomy completely removes all glandular elements of the breast. This problem forms the basis of our current study. From the Department of Surgery (WJT, RLL, EM) and the Department of Pathology (SJU), University of Calgary and the Foothills Hospital, Calgary, Alberta, Canada. Requests for reprints should be addressed to Walley J. Temple, MD, Department of Surgery, Foothills Hospital, 1403 29th Street Northwest, Calgary, Alberta, Canada, T2N 2T9. Manuscript submitted October 10, 1989, and accepted in revised form April 3, 1990.
THE AMERICAN
Stefan J. Urbanski,
MD,
PATIENTS
MD, Calgary,Alberta, Canada
AND METHODS
Five patients with high-risk histories for breast cancer were prospectively studied. The patients’ histories included two sisters, aged 29 and 3 1, with nine breast cancers in their family including grandmother, mother, and seven sisters; one patient had a history of a sister and an aunt with breast cancer and a biopsy of a breast mass showing atypical epithelial hyperplasia; one patient had a stage I breast cancer in one breast and a strong family history of breast cancer; and one patient had a biopsy diagnosis of intraductal carcinoma with a sister and aunt who had breast cancer. All patients were estimated to have a 30% to 50% chance of developing breast cancer, many within 10 years, and they were counseled carefully as to the cosmetic problems associated with prophylactic operation versus the options of careful clinical follow-up [4-71. These estimates were corroborated by genetic counseling. The surgical operation included a bilateral total mastectomy in each patient. The nipple was excised with the breast and a short transverse incision extended laterally from the nipple complex. These flaps were raised in the subcutaneous layer just below the dermis and above the breast tissue. The dissection was extended to just below the clavicle superiorly, into the axilla, frequently removing the lower one or two nodes, laterally to the latissimus dorsi and inferiorly to the rectus insertion on the ribs. In the first three patients, the pectoralis fascia was excised with the specimen, but in the last two patients a layer of pectoralis major muscle was included beneath the breast. Frozen sections were randomly obtained from the upper and lower flaps, the tail of the breast, and the pectoralis major muscle in all patients. When all the margins were determined to be clear, tissue expanders were inserted in the patient beneath the pectoralis major and the wounds were closed with a suction drain inserted to the depth of the wound. Postoperatively, these expanders were gradually inflated and a permanent prosthesis was subsequently inserted. In two patients, multiple full-thickness skin biopsies were taken from the skin flaps and sent for histopathologic evaluation. Pathology: The specimen was submitted fresh to the laboratory and all resection margins were painted with silver nitrate. Multiple sections, approximately 700 per breast, were taken from the periphery to detect areas where glandular tissues might extend to the margins. RESULTS
The examination of the breast specimens from three patients demonstrated breast tissue extending into the pectoralis fascia. In the three patients in whom a 2-mm to JOURNAL
OF SURGERY
VOLUME
161
APRIL
1991
413
Flgure 1. Postoperative cosmetic result after total mastectomy is acceptable but not as satisfactory as after a lesser subcutaneous mastectomy.
This detailed histologic examination of the microscop ic extent of the breast demonstrates that breast tissue is in areas either not suspected or not realized previously. The extensive sectioning of the specimen done in this study is not indicated routinely, but frozen section of worrisome areas and particularly in the tail of the breast and lower flap are necessary if one wishes to document clearance of breast tissue. In two patients, the skin inferior to the nipple was intimately adherent to the breast parenchyma. In addition, the breast gland extends into the pectoralis fascia and occasionally may even continue a short distance into the muscle [8]. Grossly, it was not easy to identify the edge of the breast tissue, especially in the axillary tail. Extending the dissection into the axilla through the clavipectoral fascia avoided this problem.
It would appear from the study that a total extirpation of all glandular breast tissue would include even more extensive surgery than routinely done for total mastectomy for cancer. In cancer patients, it is not currently felt that a thin flap is required, but in two of our high-risk patients, particularly the smaller-breasted patients, such flaps would have harbored a considerable amount of microscopic breast tissue. Similarly, total mastectomy for breast cancer includes pectoralis fascia but not the underlying layer of the muscle. A radial incision extending laterally from the nipple is an excellent approach giving equal access to all parts of the breast. This incision can easily be covered by any sort of clothing that the patient wishes to wear. An attempt to completely remove the breast through a submammary approach is not possible. Although a previous study of microscopic breast glandular distribution has not been performed, the intimacy of the breast parenchyma with the skin or muscle was suggested by Hicken’s [9] study in 1940 in a somewhat different manner. He observed in 385 mammograms, in which contrast had been injected into the duct, that breast tissue was widely distributed over the chest wall. He pursued this clinical observation in 17 mastectomy specimens by injecting the ducts with methylene blue. Dye leaked onto the surface in 94%, 88%, 33%, and 11% of the subareolar, axillary, sternal, and epigastric zones, respectively. In 75%, dye leaked in multiple areas. No controls for hydrostatic pressure were used, and this left the possibility that the ducts had merely been ruptured. In addition, no details of the surgery were given so that the extent of surgery could not be determined. Our report, however, corroborates this previous observation. This study does not answer whether total removal of all breast tissue is necessary to prevent cancer, but it does suggest that as close to 100% of the breast tissue may be removed with careful and precise modification of the total mastectomy procedure done for breast cancer. In all
414
161
3-mm layer of pectoralis major muscle was included, the margins were free of breast tissue. In one, an isolated breast duct was seen in the excised striated muscle. All the other margins were found to be negative for breast tissue. In two patients, eight random biopsies of the flaps revealed no glandular tissue. In the patients with frozen sections, two revealed breast tissue in the lower flap and it was necessary to dissect all tissue off the dermis of the flap in this area. In one patient, breast tissue was found in the axilla and the dissection was extended higher up into the tail of Spence. In the four specimens where the areola was dissected separately, leaving no subcutaneous tissue, breast tissue was seen in two of the specimens. The cosmetic results in the patients were all considered satisfactory, although in one patient latissimus dorsi flaps were needed to provide an adequate pocket for a prosthesis. In a mean follow-up of 5 years, no patient has developed a carcinoma. Ten separate breasts were studied. The pathologic diagnosis of three patients include two with atypical lobular hyperplasia and one with lobular carcinoma in situ.
COMMENTS
THE AMERICAN
JOURNAL
OF SURGERY
VOLUME
APRIL
1991
patients, the final reconstruction was satisfactory to excellent, but the authors would agree that cosmetic results are better if a subcutaneous mastectomy with preservation of the nipple is performed. The available data suggest that residual gross breast tissue is still at high risk for development of breast cancer [2,10]. We believe that an attempt should be made to remove all glandular elements if prophylactic surgery for a high-risk patient is being done. However, we do not think that this is required for those patients with severe fibrocystic changes not responding to the usual measures to control the often painful, worrisome, and grossly nodular breasts. We also do not believe that this procedure is the first choice for patients but only in those who cannot live with close followup as an alternative approach for their risk of developing breast cancer. The science of estimating risk for breast cancer is both controversial and inexact, as nicely discussed by Spratt et al [ 111. We strongly recommend that when this is undertaken, it should be done with the most careful consideration with the patient, husband, and family. A few months should be taken to make this decision, with the patient seeing various consultants, including genetic counselors, to make sure that she understands the nature of the procedure and the best estimate of risk. With these precautions, none of these patients has regretted their less-than-perfect result and their relief from the significant worry has more than made up for their sacrifice in cosmesis (Figure 1) [12]. In conclusion, if total glandular extirpation of the breast is intended, then mastectomy must be extended to include a layer of pectoralis major fascia and into the lower-level axilla. The lower flaps, in particular, must be made very thin, and frozen sections are particularly help ful to guide one in these areas. In principle, this is the superior operation for preventing breast cancer, but its
prophylactic value still remains to be shown. It is still possible that occasional foci of breast epithelium may remain despite this approach, and patients should continue to have yearly follow-up with their physician for this particular risk [3].
REFERENCES 1. Synderman RK. Prophylactic mastectomy: pros and cons. Cancer 1984; 53: 803-8. 2. Jackson CF, Palmquist M, Swanson J, et al. The effectiveness of prophylactic subcutaneous mastectomy in Sprague-Dawley rats induced with 7,12-demethylbenzanthracene. Plast Reconstr Surg 1984; 73: 249-60. 3. Humphrey LJ. Subcutaneous mastectomy is not a prophylaxis against carcinoma of the breast: opinion or knowledge? Am J Surg 1983; 145: 311-2. 4. Anderson DE. Genetic study of breast cancer: identification of a high risk group. Cancer 1974; 34: 1090-7. 5. Harris RE, Lynch HT, Guirgis HA. Familial breast cancer: risk to the contralateral breast. J Nat1 Cancer Inst 1978; 60: 955-60. 6. Anderson DE. A genetic study of human breast cancer. J Nat1 Cancer Inst 1972; 48: 1029-34. 7. Dupont WD, Page DL. Risk factors for breast cancer in women with proliferative breast disease. N Engl J Med 1985; 312: 146-51. 8. Davies DV, Coupland RE. Gray’s anatomy. London: Longmans, 1967: 1583. 9. Hicken NF. Mastectomy. Clinical pathologic study demonstrating why most mastectomies result in incomplete removal of the mammary gland. Arch Surg 1940; 40: 6-14. 10. Pennisi VR, Capozzi A. The incidence of obscure carcinoma in subcutaneous mastectomy: results of a national survey. Plast Reconstr Surg 1975; 56: 9-12. 11. Spratt JS, Greenberg RA, Kuhns JG, Amin EA. Breast cancer risk: a review of definitions and assessment of risk. J Surg Oncol 1988; 41: 42-6. 12. Rutqvist LE, Wallgren A, Nilsson B. Is breast cancer a curable disease? A study of 14,731 women with breast cancer from the cancer registry of Norway. Cancer 1984; 53: 1793-1800.
EDITORIAL COMMENT
Michael J. Edwards,
MD, Louisville, Kentucky
Decisions concerning the proper management of women at high risk for the development of breast cancer frequently focus on indications for bilateral mastectomy based solely on the patient’s estimated risk of subsequent breast cancer. The assumption is often made that prophylactic mastectomy definitively eliminates further cancer risk. However, the thera-
From the Division of Surgical Oncology, Department of Surgery, Uniiersity of Lo%ville, Louisville, Kentucky.
peutic value of prophylactic mastectomy, as compared with serial physical and radiologic examinations, remains ill-defined. Assuming complete removal of all breast parenchyma, the incidence of subsequent breast carcinoma should be decreased. The Achilles heel of prophylactic mastectomy is clearly underscored by the authors’ conclusion that total mastectomy is most diflicult, and when attempted, often incompletely removes all breast tissue. This report further defines specific anatomic regions where residual breast parenchyma is likely after attempted total mastectomy and pro-
vides technical recommendations for a more complete excision. Clearly the risk of breast cancer is not completely eliminated by prophylactic mastectomy. Whether any decrease in the incidence of breast cancer occurs by a less than total excision of the breast parenchyma is unknown. The authors’ recognition that total mastectomy frequently results in incomplete excision with residual breast parenchyma provides sound scientific reasoning for a persistent risk of carcinoma and underscores the importance of careful and long-term follow-up of these highrisk patients.
THE AMERICAN JOURNAL OF SURGERY
VOLUME 161 APRIL 1991
415
PAPERS
Technical Considerations for Prophylactic Mastectomy in Patients at High Risk for Breast Cancer Walley J. Temple,
MD,
Robert L. Lindsay,
MD,
Enzio Magi,
A study of 5 patients and 10 mastectomy specimens was performed to identify the extent of surgery necessary to completely remove all breast tissue in patients having prophylactic mastectomies. A standard total mastectomy performed for breast cancer was shown to frequently leave breast tissue within the superficial pectoralis major muscle and the lower skin flap. Frozen section analysis of margins was found to be essential to clear the axillary extension of the breast and lower skin flap in particular. The value of more extensive surgery to remove all glandular elements of the breast in the high-risk patient remains to be demonstrated.
he controversy concerning the extent of prophylactic mastectomy needed for high-risk patients to reduce T the risk of breast cancer developing remains unresolved [I]. The most common procedure done for this indication is the subcutaneous mastectomy. This leaves behind a substantial amount of glandular tissue in the tail of the breast, beneath the nipple, and in the relatively thick skin flaps that are developed. It has been estimated that 5% of the breast tissue remains after such operations. This type of procedure gives a much better cosmetic result but has been associated with an incidence of at least 1% breast cancer in anecdotal reports of fairly short follow-up. For this reason, a number of surgeons believe that a total mastectomy is theoretically a superior operation to a subcutaneous mastectomy [2,3]. However, no well-done study has been completed that establishes the adequacy of a total mastectomy procedure to determine if a total mastectomy completely removes all glandular elements of the breast. This problem forms the basis of our current study. From the Department of Surgery (WJT, RLL, EM) and the Department of Pathology (SJU), University of Calgary and the Foothills Hospital, Calgary, Alberta, Canada. Requests for reprints should be addressed to Walley J. Temple, MD, Department of Surgery, Foothills Hospital, 1403 29th Street Northwest, Calgary, Alberta, Canada, T2N 2T9. Manuscript submitted October 10, 1989, and accepted in revised form April 3, 1990.
THE AMERICAN
Stefan J. Urbanski,
MD,
PATIENTS
MD, Calgary,Alberta, Canada
AND METHODS
Five patients with high-risk histories for breast cancer were prospectively studied. The patients’ histories included two sisters, aged 29 and 3 1, with nine breast cancers in their family including grandmother, mother, and seven sisters; one patient had a history of a sister and an aunt with breast cancer and a biopsy of a breast mass showing atypical epithelial hyperplasia; one patient had a stage I breast cancer in one breast and a strong family history of breast cancer; and one patient had a biopsy diagnosis of intraductal carcinoma with a sister and aunt who had breast cancer. All patients were estimated to have a 30% to 50% chance of developing breast cancer, many within 10 years, and they were counseled carefully as to the cosmetic problems associated with prophylactic operation versus the options of careful clinical follow-up [4-71. These estimates were corroborated by genetic counseling. The surgical operation included a bilateral total mastectomy in each patient. The nipple was excised with the breast and a short transverse incision extended laterally from the nipple complex. These flaps were raised in the subcutaneous layer just below the dermis and above the breast tissue. The dissection was extended to just below the clavicle superiorly, into the axilla, frequently removing the lower one or two nodes, laterally to the latissimus dorsi and inferiorly to the rectus insertion on the ribs. In the first three patients, the pectoralis fascia was excised with the specimen, but in the last two patients a layer of pectoralis major muscle was included beneath the breast. Frozen sections were randomly obtained from the upper and lower flaps, the tail of the breast, and the pectoralis major muscle in all patients. When all the margins were determined to be clear, tissue expanders were inserted in the patient beneath the pectoralis major and the wounds were closed with a suction drain inserted to the depth of the wound. Postoperatively, these expanders were gradually inflated and a permanent prosthesis was subsequently inserted. In two patients, multiple full-thickness skin biopsies were taken from the skin flaps and sent for histopathologic evaluation. Pathology: The specimen was submitted fresh to the laboratory and all resection margins were painted with silver nitrate. Multiple sections, approximately 700 per breast, were taken from the periphery to detect areas where glandular tissues might extend to the margins. RESULTS
The examination of the breast specimens from three patients demonstrated breast tissue extending into the pectoralis fascia. In the three patients in whom a 2-mm to JOURNAL
OF SURGERY
VOLUME
161
APRIL
1991
413
Flgure 1. Postoperative cosmetic result after total mastectomy is acceptable but not as satisfactory as after a lesser subcutaneous mastectomy.
This detailed histologic examination of the microscop ic extent of the breast demonstrates that breast tissue is in areas either not suspected or not realized previously. The extensive sectioning of the specimen done in this study is not indicated routinely, but frozen section of worrisome areas and particularly in the tail of the breast and lower flap are necessary if one wishes to document clearance of breast tissue. In two patients, the skin inferior to the nipple was intimately adherent to the breast parenchyma. In addition, the breast gland extends into the pectoralis fascia and occasionally may even continue a short distance into the muscle [8]. Grossly, it was not easy to identify the edge of the breast tissue, especially in the axillary tail. Extending the dissection into the axilla through the clavipectoral fascia avoided this problem.
It would appear from the study that a total extirpation of all glandular breast tissue would include even more extensive surgery than routinely done for total mastectomy for cancer. In cancer patients, it is not currently felt that a thin flap is required, but in two of our high-risk patients, particularly the smaller-breasted patients, such flaps would have harbored a considerable amount of microscopic breast tissue. Similarly, total mastectomy for breast cancer includes pectoralis fascia but not the underlying layer of the muscle. A radial incision extending laterally from the nipple is an excellent approach giving equal access to all parts of the breast. This incision can easily be covered by any sort of clothing that the patient wishes to wear. An attempt to completely remove the breast through a submammary approach is not possible. Although a previous study of microscopic breast glandular distribution has not been performed, the intimacy of the breast parenchyma with the skin or muscle was suggested by Hicken’s [9] study in 1940 in a somewhat different manner. He observed in 385 mammograms, in which contrast had been injected into the duct, that breast tissue was widely distributed over the chest wall. He pursued this clinical observation in 17 mastectomy specimens by injecting the ducts with methylene blue. Dye leaked onto the surface in 94%, 88%, 33%, and 11% of the subareolar, axillary, sternal, and epigastric zones, respectively. In 75%, dye leaked in multiple areas. No controls for hydrostatic pressure were used, and this left the possibility that the ducts had merely been ruptured. In addition, no details of the surgery were given so that the extent of surgery could not be determined. Our report, however, corroborates this previous observation. This study does not answer whether total removal of all breast tissue is necessary to prevent cancer, but it does suggest that as close to 100% of the breast tissue may be removed with careful and precise modification of the total mastectomy procedure done for breast cancer. In all
414
161
3-mm layer of pectoralis major muscle was included, the margins were free of breast tissue. In one, an isolated breast duct was seen in the excised striated muscle. All the other margins were found to be negative for breast tissue. In two patients, eight random biopsies of the flaps revealed no glandular tissue. In the patients with frozen sections, two revealed breast tissue in the lower flap and it was necessary to dissect all tissue off the dermis of the flap in this area. In one patient, breast tissue was found in the axilla and the dissection was extended higher up into the tail of Spence. In the four specimens where the areola was dissected separately, leaving no subcutaneous tissue, breast tissue was seen in two of the specimens. The cosmetic results in the patients were all considered satisfactory, although in one patient latissimus dorsi flaps were needed to provide an adequate pocket for a prosthesis. In a mean follow-up of 5 years, no patient has developed a carcinoma. Ten separate breasts were studied. The pathologic diagnosis of three patients include two with atypical lobular hyperplasia and one with lobular carcinoma in situ.
COMMENTS
THE AMERICAN
JOURNAL
OF SURGERY
VOLUME
APRIL
1991
patients, the final reconstruction was satisfactory to excellent, but the authors would agree that cosmetic results are better if a subcutaneous mastectomy with preservation of the nipple is performed. The available data suggest that residual gross breast tissue is still at high risk for development of breast cancer [2,10]. We believe that an attempt should be made to remove all glandular elements if prophylactic surgery for a high-risk patient is being done. However, we do not think that this is required for those patients with severe fibrocystic changes not responding to the usual measures to control the often painful, worrisome, and grossly nodular breasts. We also do not believe that this procedure is the first choice for patients but only in those who cannot live with close followup as an alternative approach for their risk of developing breast cancer. The science of estimating risk for breast cancer is both controversial and inexact, as nicely discussed by Spratt et al [ 111. We strongly recommend that when this is undertaken, it should be done with the most careful consideration with the patient, husband, and family. A few months should be taken to make this decision, with the patient seeing various consultants, including genetic counselors, to make sure that she understands the nature of the procedure and the best estimate of risk. With these precautions, none of these patients has regretted their less-than-perfect result and their relief from the significant worry has more than made up for their sacrifice in cosmesis (Figure 1) [12]. In conclusion, if total glandular extirpation of the breast is intended, then mastectomy must be extended to include a layer of pectoralis major fascia and into the lower-level axilla. The lower flaps, in particular, must be made very thin, and frozen sections are particularly help ful to guide one in these areas. In principle, this is the superior operation for preventing breast cancer, but its
prophylactic value still remains to be shown. It is still possible that occasional foci of breast epithelium may remain despite this approach, and patients should continue to have yearly follow-up with their physician for this particular risk [3].
REFERENCES 1. Synderman RK. Prophylactic mastectomy: pros and cons. Cancer 1984; 53: 803-8. 2. Jackson CF, Palmquist M, Swanson J, et al. The effectiveness of prophylactic subcutaneous mastectomy in Sprague-Dawley rats induced with 7,12-demethylbenzanthracene. Plast Reconstr Surg 1984; 73: 249-60. 3. Humphrey LJ. Subcutaneous mastectomy is not a prophylaxis against carcinoma of the breast: opinion or knowledge? Am J Surg 1983; 145: 311-2. 4. Anderson DE. Genetic study of breast cancer: identification of a high risk group. Cancer 1974; 34: 1090-7. 5. Harris RE, Lynch HT, Guirgis HA. Familial breast cancer: risk to the contralateral breast. J Nat1 Cancer Inst 1978; 60: 955-60. 6. Anderson DE. A genetic study of human breast cancer. J Nat1 Cancer Inst 1972; 48: 1029-34. 7. Dupont WD, Page DL. Risk factors for breast cancer in women with proliferative breast disease. N Engl J Med 1985; 312: 146-51. 8. Davies DV, Coupland RE. Gray’s anatomy. London: Longmans, 1967: 1583. 9. Hicken NF. Mastectomy. Clinical pathologic study demonstrating why most mastectomies result in incomplete removal of the mammary gland. Arch Surg 1940; 40: 6-14. 10. Pennisi VR, Capozzi A. The incidence of obscure carcinoma in subcutaneous mastectomy: results of a national survey. Plast Reconstr Surg 1975; 56: 9-12. 11. Spratt JS, Greenberg RA, Kuhns JG, Amin EA. Breast cancer risk: a review of definitions and assessment of risk. J Surg Oncol 1988; 41: 42-6. 12. Rutqvist LE, Wallgren A, Nilsson B. Is breast cancer a curable disease? A study of 14,731 women with breast cancer from the cancer registry of Norway. Cancer 1984; 53: 1793-1800.
EDITORIAL COMMENT
Michael J. Edwards,
MD, Louisville, Kentucky
Decisions concerning the proper management of women at high risk for the development of breast cancer frequently focus on indications for bilateral mastectomy based solely on the patient’s estimated risk of subsequent breast cancer. The assumption is often made that prophylactic mastectomy definitively eliminates further cancer risk. However, the thera-
From the Division of Surgical Oncology, Department of Surgery, Uniiersity of Lo%ville, Louisville, Kentucky.
peutic value of prophylactic mastectomy, as compared with serial physical and radiologic examinations, remains ill-defined. Assuming complete removal of all breast parenchyma, the incidence of subsequent breast carcinoma should be decreased. The Achilles heel of prophylactic mastectomy is clearly underscored by the authors’ conclusion that total mastectomy is most diflicult, and when attempted, often incompletely removes all breast tissue. This report further defines specific anatomic regions where residual breast parenchyma is likely after attempted total mastectomy and pro-
vides technical recommendations for a more complete excision. Clearly the risk of breast cancer is not completely eliminated by prophylactic mastectomy. Whether any decrease in the incidence of breast cancer occurs by a less than total excision of the breast parenchyma is unknown. The authors’ recognition that total mastectomy frequently results in incomplete excision with residual breast parenchyma provides sound scientific reasoning for a persistent risk of carcinoma and underscores the importance of careful and long-term follow-up of these highrisk patients.
THE AMERICAN JOURNAL OF SURGERY
VOLUME 161 APRIL 1991
415
