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Villous adenomas of the colon and rectum
Villous Adenomas of the Colon and Rectum M. Rem Jahadi, MD, Dallas, Texas Alvin Baldwin, Jr, MD, Dallas, Texas
Despite a vast amount of literature on villous adenomas of the colon and rectum, much confusion and controversy still exists about the pathologic nature, frequency of malignancy, and proper treatment of this neoplasm. The present study of villous adenomas was undertaken in an attempt to examine the results of the various forms of treatment of these lesions to establish guidelines for the proper management of these tumors. Material and Methods This retrospective study reviews the clinical case records of all patients with villous adenomas of the colon and rectum treated at Baylor University Medical Center in Dallas from 1960 to 1973. Only cases with a documented histologic diagnosis of papillary adenomas were included. All cases of mixed adenomas, papillary adenocarcinomas, and nonspecified adenomas with atypia were excluded. Five year follow-up information was obtained from the patients’ charts and the records in our
Tumor Registry.
From the Department of Colon and Rectal Surgery, Baylor University Medical Center, Dallas, Texas. Reprint requests should be addressed to M. Reza Jahadi. MD. 2202 Avenue L. Galveston, Texas 77550. Presented at the Twenty-Seventh Annual Meeting of the Southwestern Surgical Congress, Las Vegas, Nevada, April 21-24, 1975.
Vokune 130, December 1975
Results During this thirteen year period, 264 patients with villous adenomas of the colon and rectum were treated. Sex distribution was almost equal with 138 females and 126 males; 92 per cent of the patients were Caucasian and the remainder were black. Ages ranged from twenty-eight to eightynine years with an average of sixty-two years; 84 per cent of the patients were fifty years or older and the highest incidence was found in the seventh decade. The average age of patients with benign adenomas was fifty-nine years and malignant adenomas sixty-eight years, Rectal bleeding (35 per cent), mucoid diarrhea (22 per cent), and abdominal pain (10 per cent) were the most frequent presenting complaints in symptomatic patients. Various clinical presentations including anemia, weight loss, prolapsing tumor, palpable abdominal mass, and the depletion syndrome were noted in 18 per cent of the patients. The remaining 15 per cent of the patients were asymptomatic with discovery of their lesions during routine examinations. Lesions were predominantly located in the rectum and rectosigmoid (72 per cent) and the remaining 28 per cent occurred throughout the rest of the large bowel. Ninety-two patients had associated diseases of which thirty-two were adenomatous polyps of the colon and rectum. Of the associated lesions 41 per cent were malignant; adenocar-
729
Jahadi and Baldwin
TABLE
I
Treatment of Malignant Recurrence
Treatment Local excision Anterior or segmental resectlon Abdominoperineal resection Colotomy and excision Pull-through Colectomy Total
Adenoma
versus
Number of Patients
Number of Recurrences
48 52
14 3
18
0
13 2 1 145
5 0 0 22
cinema of the colon and rectum was the most common. The tumors were classified by size: of adenomas less than 2 cm in diameter, sixty were benign and twenty-six were malignant; of 120 tumors from 2 to 5 cm in diameter, thirty-nine were benign and eighty-one were malignant; and of the fifty-eight tumors greater than 5 cm in diameter, twenty were benign and thirty-eight were malignant. An initial biopsy specimen of the lesions in 192 patients was examined. Of the 128 that were reported benign, fifty-one patients were found to have malignancy in their resected specimen. Based on final histopathologic diagnosis in 264 patients, 45 per cent of the tumors were diagnosed as benign papillary adenomas with or without atypia. In 145 patients the adenomas were found to be malignant. Of these, eighty-seven patients had noninvasive carcinoma and forty-eight patients showed invasive carcinoma. In the group of 119 patients with benign adenomas with or without atypia, eleven had tumors accompanied by adenocarcinoma of the colon and rectum, and in those patients primary cancer operations were performed. The treatment in the remaining 108 patients consisted of local excision of one form or another in fifty-six patients. Twentyone patients underwent either an anterior or segmental resection. In another twenty-four patients the tumor was excised through a colotomy. Five patients were treated with abdominoperineal resection and two had pull-through procedure. Subsequent follow-up in this group of patients showed eighteen local recurrences (seventeen in patients with local excision and one with colotomy and excision). Fifteen of these local recurrences were benign and in three patients the recurrent lesions were malignant. All of the three malignant recurrences contained noninvasive carcinoma. Two pa-
730
tients with benign adenomas died without any evidence of local recurrence or metastasis three and five years after their diagnosis was made. One hundred forty-five patients had malignant villous adenomas at the time of their initial treatment. Of these, forty-eight patients had invasive carcinoma. The primary treatment in this group of patients consisted of a variety of procedures listed in Table I. Of twenty-two local recurrences, fourteen had been treated by local excision of the tumor. In this group, eighty-two patients were operated before 1970. Two patients were lost to follow-up, but a minimum of five year follow-up data were available in the remaining eighty patients. There were two operative deaths, an operative mortality of 2.5 per cent. Overall, twelve deaths were recorded, including the two operative deaths, for a five year survival rate of 75 per cent in patients with malignant adenomas. Only eight patients died of metastatic diseases originating in their villous adenomas, and of these, seven patients had invasive carcinoma at the time of initial treatment.
Comments The findings in the present study in regard to patients’ age, sex, race, and presenting symptoms do not differ from those of previous reports in the literature [3,6]. Several authors [9,10] have studied villous tumors with regard to the relationship between size of the adenoma and incidence of malignancy. They concluded that although larger lesions have a greater chance of being malignant, size alone is of little help in deciding the issue of malignancy. However, a closer association between tumor size and incidence of malignancy has been reported by others [2,4]. In this series a positive correlation between tumor size and incidence of malignancy was noted. The chance of malignancy in adenomas greater than 2 cm in diameter was twice that of lesions less than 2 cm in diameter. This finding may suggest that a wider excision or a resection would be more beneficial in treating a large adenoma. We have encountered a 40 per cent chance of error in histologic diagnosis on the first random biopsy in patients in whom carcinoma arose in a villous adenoma. A similar finding has been reported by McCabe et al [3] and Orringer and Eggleston [5]. This indicates that the surgeon should not rely heavily on a frozen section or a small biopsy when choosing the method of treatment.
The American Journal of Surgery
Villous Adenomas of Colon and Rectum
The villous tumor causing significant volume problem and electrolytic imbalances has been well delineated in previous reports [1,7]. Review by Schrock and Polk [8] in 1973 of the world literature on villous adenomas producing the depletion syndrome has disclosed fifty-one cases. The characteristic presentation was a history of long-standing diarrhea with associated weakness, hypotension, hyponatremia, hypokalemia, prerenal azotemia, and mixed acid base derangments. Two such instances were found in our series. Although this is a rare occurrence, representing less than 1 per cent, awareness of such a clinical entity would be useful in suspecting the diagnosis of villous tumor in any patient with a depletion syndrome. The incidence of malignancy in patients with villous adenoma varies greatly from one series to another, ranging from 13 to 68.4 per cent [9,10]. Part of this large discrepancy results from the pathologic criteria used to recognize malignant changes. Some investigators consider atypia as malignant changes, whereas others believe that invasion of musclaris mucosa by carcinoma should be the criteria for determining malignancy. In the present series, 55 per cent of the lesions were reported malignant, but in only 22 per cent was evidence of invasion found. With such a low incidence of invasive carcinoma, clinicians should expect a large difference between the pathologic and the clinical behavior of this neoplasm as compared with that of adenocarcinoma of the colon and rectum. Incidence of local recurrence in patients with villous adenomas located in the colon was lesser than that in patients with rectal lesions. This is perhaps the result of a slower progression of the colonic adenomas or due to the fact that most of the colonic lesions were treated by laparotomy because total excision could be accomplished more often. Most of the local recurrences occurred in patients whose tumors were initially treated by local excision. This suggests the probability of incomplete excision with some residual tumor being the actual cause of the recurrence. Also, when local recurrence occurs after excision of a benign adenoma, approximately 83 per cent recur as a benign lesion. No accurate explanation could be given for 17 per cent of our malignant recurrences in benign adenomas. One may assume that perhaps the initial histologic diagnosis of these adenomas was made incorrectly or that in some instances total lesion was not submitted for pathologic examination.
V0lwn0130,Decmber1975
We have encountered a 75 per cent five year survival in the malignant group that we studied. This figure is in contrast to a 41 per cent five year survival rate for primary adenocarcinoma of the rectum and rectosigmoid reported by Zollinger and Sheppard [II]. Of interest is that only about 10 per cent of our mortality is directly related to metastatic disease originating from a villous tumor. Most of these occurred in patients who initially had invasive carcinoma in their adenoma. This indicates that in the absence of invasive carcinoma, the clinical behavior of the villous adenoma is relatively benign. The proper management of a villous adenoma depends on an accurate histologic diagnosis, the size and location of the tumor, and the general condition of the patient. An attempt should be made to establish a pathologic diagnosis before a decision is made to undertake any type of surgery. Excisional biopsy of this lesion should be performed whenever possible. The large tumors above the rectum should be treated by a segmental coionic resection, but the small lesions can be managed by colotomy and polypectomy or by snare excision through the colonoscope. Benign rectal lesions or those with noninvasive carcinoma can be managed by local excision, but invasive carcinoma in a villous adenoma should be treated as any other adenocarcinoma of the rectum by radical excision. In conclusion, we believe our experience has supported the concept that the natural history and clinical course of villous adenoma are quite different from primary adenocarcinoma of the colon and rectum. This is based on a better five year survival rate, a low incidence of invasive carcinoma, and the fact that most of the originally benign adenomas usually remain benign despite local recurrence. Our plea is for a more conservative approach to the surgical treatment of villous adenomas containing noninvasive carcinoma. Summary
Our thirteen year experience with villous adenomas of the colon and rectum, embracing 264 patients, is reported. The average age of patients was sixty-two years with an almost equal sex distribution. Seventy-two per cent of the lesions occurred in the rectum and rectosigmoid and the most frequent symptoms were rectal bleeding and diarrhea. A positive correlation between size of adenoma and incidence of malignancy was noted. Although 55 per cent of the lesions were malignant,
731
Jahadi and Baldwin
only 22 per cent harbored invasive carcinoma and only 10 per cent of the deaths were due to metastatic carcinoma. It is concluded that in the absence of invasive carcinoma, the clinical behavior of this tumor is relatively benign and a more conservative approach to the surgical management of this neoplasm should be encouraged. References 1. Davis JE, Seavey PW, Sessions JT Jr: Villous adenomas of the rectum and sigmoid colon with severe fluid and electrolytes depletion. Ann Surg 155: 806, 1962. 2. Evans JT, lmahori S, Liu K: Villous adenoma of colon and rectum. J Surg Oncol4: 117, 1972. 3. McCabe JC, f&Sherry CK, Sussman EB, Gary GF: Villous tumor of the large bowel. Am J Surg 126: 336, 1973. 4. Olson RO, Davis WC: Viltous adenomas of the colon: benign or malignant? Arch Surg 98: 487, 1969. 5. Orringer MB, Eggleston JC: Papillary (villous) adenomas of colon and rectum. Surgery 72: 378, 1972. 6. Quan SH, Castro EB: Papillary adenomas (villous tumors): a review of 215 cases. Dis Co/on Rectum 14: 267. 1971. 7. Roy AD, Ellis H: Pottasiumsecreting tumors of large intestine. Lancet 1: 759, 1959. 8. Schrock LG, Polk HC Jr: Rectal villous adenoma producing hypokalemia. Am Surg 40: 54, 1974. 9. Sunderland DA, Binkley GE: Papillary adenomas of the large intestine: a clinical and morphological study of forty-eight cases. Cancer 1: 184. 1948. 10. Wheat MW Jr, Ackerman LV: Villous adenomas of the large intestine: clinicopathotogic evaluation of 50 cases of villous adenomas with emphasis on treatment. Ann Surg 147: 476, 1958. 11. Zollinger RM, Sheppard MH: Carcinoma of the rectum and recta-sigmoid. Arch Surg 102: 335, 1971.
732
Discussion
John Whitcomb (Detroit, MI): The authors point out a correlation between tumor size and malignancy that has not been confirmed by others. They also point out that these lesions are not strictly premalignant and it is not necessary to perform radica1 surgery unless invasive cancer is found. In their lesions they show 55 per cent containing malignancy, but only 22 per cent were invasive. Hence, 88 per cent of their.lesions were benign or noninvasive with no need for additional radical operation. The rate of local recurrence, they point out, is also directly proportionate to the adequacy of the local excision. A fifty-nine year old male presented with rectal bleeding and underwent routine sigmoidoscopy examination, which was negative, and on subsequent barium enema examination a polyp was found in the midsigmoid. This was removed with the colonoscope used at the 35 cm level. A pathologic presentation of that polyp showed normal mucosa and underlying adenocarcinoma. The appropriate segment of the sigmoid colon was removed. The final pathologic report was without cancerous change. Radical operations on the low rectum for this lesion are seldom indicated, unless permanent sections from the excised adenoma reveal invasion of the muscularis mucosa. Have the authors had any experience with the abdominosacral approach in the treatment of true adenocarcinoma of the rectum? M. Reza Jahadi (closing): We have not had any experience with the abdominosacral approach. The rate of leak has been high.
Despite a vast amount of literature on villous adenomas of the colon and rectum, much confusion and controversy still exists about the pathologic nature, frequency of malignancy, and proper treatment of this neoplasm. The present study of villous adenomas was undertaken in an attempt to examine the results of the various forms of treatment of these lesions to establish guidelines for the proper management of these tumors. Material and Methods This retrospective study reviews the clinical case records of all patients with villous adenomas of the colon and rectum treated at Baylor University Medical Center in Dallas from 1960 to 1973. Only cases with a documented histologic diagnosis of papillary adenomas were included. All cases of mixed adenomas, papillary adenocarcinomas, and nonspecified adenomas with atypia were excluded. Five year follow-up information was obtained from the patients’ charts and the records in our
Tumor Registry.
From the Department of Colon and Rectal Surgery, Baylor University Medical Center, Dallas, Texas. Reprint requests should be addressed to M. Reza Jahadi. MD. 2202 Avenue L. Galveston, Texas 77550. Presented at the Twenty-Seventh Annual Meeting of the Southwestern Surgical Congress, Las Vegas, Nevada, April 21-24, 1975.
Vokune 130, December 1975
Results During this thirteen year period, 264 patients with villous adenomas of the colon and rectum were treated. Sex distribution was almost equal with 138 females and 126 males; 92 per cent of the patients were Caucasian and the remainder were black. Ages ranged from twenty-eight to eightynine years with an average of sixty-two years; 84 per cent of the patients were fifty years or older and the highest incidence was found in the seventh decade. The average age of patients with benign adenomas was fifty-nine years and malignant adenomas sixty-eight years, Rectal bleeding (35 per cent), mucoid diarrhea (22 per cent), and abdominal pain (10 per cent) were the most frequent presenting complaints in symptomatic patients. Various clinical presentations including anemia, weight loss, prolapsing tumor, palpable abdominal mass, and the depletion syndrome were noted in 18 per cent of the patients. The remaining 15 per cent of the patients were asymptomatic with discovery of their lesions during routine examinations. Lesions were predominantly located in the rectum and rectosigmoid (72 per cent) and the remaining 28 per cent occurred throughout the rest of the large bowel. Ninety-two patients had associated diseases of which thirty-two were adenomatous polyps of the colon and rectum. Of the associated lesions 41 per cent were malignant; adenocar-
729
Jahadi and Baldwin
TABLE
I
Treatment of Malignant Recurrence
Treatment Local excision Anterior or segmental resectlon Abdominoperineal resection Colotomy and excision Pull-through Colectomy Total
Adenoma
versus
Number of Patients
Number of Recurrences
48 52
14 3
18
0
13 2 1 145
5 0 0 22
cinema of the colon and rectum was the most common. The tumors were classified by size: of adenomas less than 2 cm in diameter, sixty were benign and twenty-six were malignant; of 120 tumors from 2 to 5 cm in diameter, thirty-nine were benign and eighty-one were malignant; and of the fifty-eight tumors greater than 5 cm in diameter, twenty were benign and thirty-eight were malignant. An initial biopsy specimen of the lesions in 192 patients was examined. Of the 128 that were reported benign, fifty-one patients were found to have malignancy in their resected specimen. Based on final histopathologic diagnosis in 264 patients, 45 per cent of the tumors were diagnosed as benign papillary adenomas with or without atypia. In 145 patients the adenomas were found to be malignant. Of these, eighty-seven patients had noninvasive carcinoma and forty-eight patients showed invasive carcinoma. In the group of 119 patients with benign adenomas with or without atypia, eleven had tumors accompanied by adenocarcinoma of the colon and rectum, and in those patients primary cancer operations were performed. The treatment in the remaining 108 patients consisted of local excision of one form or another in fifty-six patients. Twentyone patients underwent either an anterior or segmental resection. In another twenty-four patients the tumor was excised through a colotomy. Five patients were treated with abdominoperineal resection and two had pull-through procedure. Subsequent follow-up in this group of patients showed eighteen local recurrences (seventeen in patients with local excision and one with colotomy and excision). Fifteen of these local recurrences were benign and in three patients the recurrent lesions were malignant. All of the three malignant recurrences contained noninvasive carcinoma. Two pa-
730
tients with benign adenomas died without any evidence of local recurrence or metastasis three and five years after their diagnosis was made. One hundred forty-five patients had malignant villous adenomas at the time of their initial treatment. Of these, forty-eight patients had invasive carcinoma. The primary treatment in this group of patients consisted of a variety of procedures listed in Table I. Of twenty-two local recurrences, fourteen had been treated by local excision of the tumor. In this group, eighty-two patients were operated before 1970. Two patients were lost to follow-up, but a minimum of five year follow-up data were available in the remaining eighty patients. There were two operative deaths, an operative mortality of 2.5 per cent. Overall, twelve deaths were recorded, including the two operative deaths, for a five year survival rate of 75 per cent in patients with malignant adenomas. Only eight patients died of metastatic diseases originating in their villous adenomas, and of these, seven patients had invasive carcinoma at the time of initial treatment.
Comments The findings in the present study in regard to patients’ age, sex, race, and presenting symptoms do not differ from those of previous reports in the literature [3,6]. Several authors [9,10] have studied villous tumors with regard to the relationship between size of the adenoma and incidence of malignancy. They concluded that although larger lesions have a greater chance of being malignant, size alone is of little help in deciding the issue of malignancy. However, a closer association between tumor size and incidence of malignancy has been reported by others [2,4]. In this series a positive correlation between tumor size and incidence of malignancy was noted. The chance of malignancy in adenomas greater than 2 cm in diameter was twice that of lesions less than 2 cm in diameter. This finding may suggest that a wider excision or a resection would be more beneficial in treating a large adenoma. We have encountered a 40 per cent chance of error in histologic diagnosis on the first random biopsy in patients in whom carcinoma arose in a villous adenoma. A similar finding has been reported by McCabe et al [3] and Orringer and Eggleston [5]. This indicates that the surgeon should not rely heavily on a frozen section or a small biopsy when choosing the method of treatment.
The American Journal of Surgery
Villous Adenomas of Colon and Rectum
The villous tumor causing significant volume problem and electrolytic imbalances has been well delineated in previous reports [1,7]. Review by Schrock and Polk [8] in 1973 of the world literature on villous adenomas producing the depletion syndrome has disclosed fifty-one cases. The characteristic presentation was a history of long-standing diarrhea with associated weakness, hypotension, hyponatremia, hypokalemia, prerenal azotemia, and mixed acid base derangments. Two such instances were found in our series. Although this is a rare occurrence, representing less than 1 per cent, awareness of such a clinical entity would be useful in suspecting the diagnosis of villous tumor in any patient with a depletion syndrome. The incidence of malignancy in patients with villous adenoma varies greatly from one series to another, ranging from 13 to 68.4 per cent [9,10]. Part of this large discrepancy results from the pathologic criteria used to recognize malignant changes. Some investigators consider atypia as malignant changes, whereas others believe that invasion of musclaris mucosa by carcinoma should be the criteria for determining malignancy. In the present series, 55 per cent of the lesions were reported malignant, but in only 22 per cent was evidence of invasion found. With such a low incidence of invasive carcinoma, clinicians should expect a large difference between the pathologic and the clinical behavior of this neoplasm as compared with that of adenocarcinoma of the colon and rectum. Incidence of local recurrence in patients with villous adenomas located in the colon was lesser than that in patients with rectal lesions. This is perhaps the result of a slower progression of the colonic adenomas or due to the fact that most of the colonic lesions were treated by laparotomy because total excision could be accomplished more often. Most of the local recurrences occurred in patients whose tumors were initially treated by local excision. This suggests the probability of incomplete excision with some residual tumor being the actual cause of the recurrence. Also, when local recurrence occurs after excision of a benign adenoma, approximately 83 per cent recur as a benign lesion. No accurate explanation could be given for 17 per cent of our malignant recurrences in benign adenomas. One may assume that perhaps the initial histologic diagnosis of these adenomas was made incorrectly or that in some instances total lesion was not submitted for pathologic examination.
V0lwn0130,Decmber1975
We have encountered a 75 per cent five year survival in the malignant group that we studied. This figure is in contrast to a 41 per cent five year survival rate for primary adenocarcinoma of the rectum and rectosigmoid reported by Zollinger and Sheppard [II]. Of interest is that only about 10 per cent of our mortality is directly related to metastatic disease originating from a villous tumor. Most of these occurred in patients who initially had invasive carcinoma in their adenoma. This indicates that in the absence of invasive carcinoma, the clinical behavior of the villous adenoma is relatively benign. The proper management of a villous adenoma depends on an accurate histologic diagnosis, the size and location of the tumor, and the general condition of the patient. An attempt should be made to establish a pathologic diagnosis before a decision is made to undertake any type of surgery. Excisional biopsy of this lesion should be performed whenever possible. The large tumors above the rectum should be treated by a segmental coionic resection, but the small lesions can be managed by colotomy and polypectomy or by snare excision through the colonoscope. Benign rectal lesions or those with noninvasive carcinoma can be managed by local excision, but invasive carcinoma in a villous adenoma should be treated as any other adenocarcinoma of the rectum by radical excision. In conclusion, we believe our experience has supported the concept that the natural history and clinical course of villous adenoma are quite different from primary adenocarcinoma of the colon and rectum. This is based on a better five year survival rate, a low incidence of invasive carcinoma, and the fact that most of the originally benign adenomas usually remain benign despite local recurrence. Our plea is for a more conservative approach to the surgical treatment of villous adenomas containing noninvasive carcinoma. Summary
Our thirteen year experience with villous adenomas of the colon and rectum, embracing 264 patients, is reported. The average age of patients was sixty-two years with an almost equal sex distribution. Seventy-two per cent of the lesions occurred in the rectum and rectosigmoid and the most frequent symptoms were rectal bleeding and diarrhea. A positive correlation between size of adenoma and incidence of malignancy was noted. Although 55 per cent of the lesions were malignant,
731
Jahadi and Baldwin
only 22 per cent harbored invasive carcinoma and only 10 per cent of the deaths were due to metastatic carcinoma. It is concluded that in the absence of invasive carcinoma, the clinical behavior of this tumor is relatively benign and a more conservative approach to the surgical management of this neoplasm should be encouraged. References 1. Davis JE, Seavey PW, Sessions JT Jr: Villous adenomas of the rectum and sigmoid colon with severe fluid and electrolytes depletion. Ann Surg 155: 806, 1962. 2. Evans JT, lmahori S, Liu K: Villous adenoma of colon and rectum. J Surg Oncol4: 117, 1972. 3. McCabe JC, f&Sherry CK, Sussman EB, Gary GF: Villous tumor of the large bowel. Am J Surg 126: 336, 1973. 4. Olson RO, Davis WC: Viltous adenomas of the colon: benign or malignant? Arch Surg 98: 487, 1969. 5. Orringer MB, Eggleston JC: Papillary (villous) adenomas of colon and rectum. Surgery 72: 378, 1972. 6. Quan SH, Castro EB: Papillary adenomas (villous tumors): a review of 215 cases. Dis Co/on Rectum 14: 267. 1971. 7. Roy AD, Ellis H: Pottasiumsecreting tumors of large intestine. Lancet 1: 759, 1959. 8. Schrock LG, Polk HC Jr: Rectal villous adenoma producing hypokalemia. Am Surg 40: 54, 1974. 9. Sunderland DA, Binkley GE: Papillary adenomas of the large intestine: a clinical and morphological study of forty-eight cases. Cancer 1: 184. 1948. 10. Wheat MW Jr, Ackerman LV: Villous adenomas of the large intestine: clinicopathotogic evaluation of 50 cases of villous adenomas with emphasis on treatment. Ann Surg 147: 476, 1958. 11. Zollinger RM, Sheppard MH: Carcinoma of the rectum and recta-sigmoid. Arch Surg 102: 335, 1971.
732
Discussion
John Whitcomb (Detroit, MI): The authors point out a correlation between tumor size and malignancy that has not been confirmed by others. They also point out that these lesions are not strictly premalignant and it is not necessary to perform radica1 surgery unless invasive cancer is found. In their lesions they show 55 per cent containing malignancy, but only 22 per cent were invasive. Hence, 88 per cent of their.lesions were benign or noninvasive with no need for additional radical operation. The rate of local recurrence, they point out, is also directly proportionate to the adequacy of the local excision. A fifty-nine year old male presented with rectal bleeding and underwent routine sigmoidoscopy examination, which was negative, and on subsequent barium enema examination a polyp was found in the midsigmoid. This was removed with the colonoscope used at the 35 cm level. A pathologic presentation of that polyp showed normal mucosa and underlying adenocarcinoma. The appropriate segment of the sigmoid colon was removed. The final pathologic report was without cancerous change. Radical operations on the low rectum for this lesion are seldom indicated, unless permanent sections from the excised adenoma reveal invasion of the muscularis mucosa. Have the authors had any experience with the abdominosacral approach in the treatment of true adenocarcinoma of the rectum? M. Reza Jahadi (closing): We have not had any experience with the abdominosacral approach. The rate of leak has been high.