Anorectal melanoma. The role of posterior pelvic exenteration

Anal melanoma

Anal melanoma is rare and aggressive malignancy. Patients commonly present with advanced, even metastatic disease. Unlike cutaneous melanoma, anal melanoma has no known risk factors. Surgical excision remains the cornerstone of therapy. There are no long-term survivors of stage II or III disease; therefore, early diagnosis and treatment remain crucial. There are no trials definitively proving abdominal perineal resection (APR) or wide local excision (WLE) to yield superior long-term survival. APR may offer a higher rate of local control, whereas WLE offers a much less morbid operation. Adjuvant chemotherapy, interferon, and radiation may offer some benefit.

Melanoma of the anorectal region: the experience of the National Cancer Institute of Milano

AIMS

This study describes the experience of the National Cancer Institute of Milano in the treatment of anorectal melanoma over the last 32 years.

METHODS

The influence of different surgical approaches on local care and final outcome was investigated on 40 completely evaluable patients, followed for a median follow-up time of 75 months. The analysis was carried out by calculating and comparing overall survival, disease-free survival and cumulative incidence curves of disease recurrence.

RESULTS

Thirty-one patients underwent radical surgery: nine abdominoperineal resections, four total rectal resections and coloendoanal anastomosis, and 18 local excisions. The remaining nine patients received palliative treatments. Median overall survival time for patients receiving non-radical treatments was poor: only 6 months. However, even when a radical surgery was undergone, the prognosis of patients with anal melanoma remains dismal. Local relapse incidence was 45.8% for the limited surgery group, but non-existent for the extended-surgery group (p = 0.007). However, the median disease-free survival time was 7 and 9 months for patients receiving limited or major surgery (p = 0.97). Overall survival was 17 months, irrespective of the adopted surgery.

CONCLUSION

Prognosis of anal melanoma remains poor. Final outcome is not influenced by modality of surgery. A limited but radical excision can be considered whenever possible while a major demolitive surgery should be applied only for therapy of advanced or bulky lesions.

Anorectal melanoma: report of three cases with extended follow-up

Primary anorectal melanoma is rare. There is controversy regarding the best surgical treatment because of its poor prognosis. Three cases with extended follow-up are reported in this article. A 53-year-old woman with rectal bleeding was diagnosed with a melanoma of the rectum and underwent an abdominoperineal resection. The patient died with distant metastases 8 months later. An 80-year-old woman with rectal bleeding was diagnosed with a melanoma of the rectum and underwent a transanal local excision. She remains alive 4 years later but with locally recurrent disease. A 78-year-old man with rectal bleeding was diagnosed with a melanoma of the rectum and underwent an abdominoperineal resection. He died with local and metastatic disease 25 months later. Recent trends favor local excision when technically feasible, although some patients may require an abdominoperineal resection of the rectum, especially for larger tumors.

Surgical therapy for anorectal melanoma

BACKGROUND

Anorectal melanoma is a rare but highly lethal malignancy. Historically, radical resection was considered the "gold standard" for treatment of potentially curable anorectal melanoma. The dismal prognosis of this disease has prompted us to recommend wide local excision as the initial therapeutic approach. The purpose of this study was to review our results in patients who underwent wide local excision or radical surgery (abdominoperineal resection [APR]) for localized anorectal melanoma.

STUDY DESIGN

We reviewed the charts of all patients referred for resection of anorectal melanoma between 1988 and 2002. Endpoints included overall survival, disease-free survival, and local, regional, or systemic recurrence.

RESULTS

Fifteen patients underwent curative-intent surgery; four underwent APR and 11 underwent wide local excision. Eight patients (53%) are alive; 7 (47%) are disease-free (followup 6 months to 13 years). Of 12 patients who have been followed for more than 2 years, 4 are alive (33%) and 3 are disease-free (25%). Seven patients have been followed for more than 5 years and two are alive and disease-free (29%). All of the longterm survivors underwent local excision as the initial operation. There were no differences in local recurrence, systemic recurrence, disease-free survival, or overall survival between the APR group and the local excision group. Local recurrence occurred in 50% of the APR group and 18% of the local excision group; regional recurrence occurred in 25% versus 27%. Distant metastases were common (75% versus 36%).

CONCLUSION

In patients who have undergone resection with curative intent for anorectal melanoma, most recurrences occur systemically regardless of the initial surgical procedure. Local resection does not increase the risk of local or regional recurrence. APR offers no survival advantage over local excision. We advocate wide local excision as primary therapy for anorectal melanoma when technically feasible.

Anorectal melanoma--an incurable disease?

PURPOSE

This study was designed to describe recurrence and survival rates after operative treatment for anorectal melanoma and to identify predictive factors for recurrence.

METHODS

Records of 50 patients with anorectal melanoma from 1939 to 1993 were reviewed.

RESULTS

Overall five-year survival and disease-free survival were 22 and 16 percent, respectively. At the time of diagnosis, 26 percent of patients had metastatic disease, and all died within 12 (mean, 6.3) months. Five-year survival and recurrence rates were identical after either abdominoperineal resection (APR) or wide local excision, both with curative intent. Gender, size of tumor, presence of melanin, positive perirectal lymph nodes, or treatment were not predictive of recurrence. Anorectal melanoma was found incidentally after hemorrhoidectomy or polypectomy in five patients. Three other patients underwent an excisional biopsy of a lesion measuring less than 2 cm. Of these eight patients, five underwent APR and three underwent wide local excision with no microscopic residual tumor at pathology. All developed regional or systemic recurrence at a mean of 21 (range, 4-88) months, and all died of their disease at a mean of 29 (range, 5-98) months.

CONCLUSION

Prognosis for anorectal melanoma is poor, irrespective of surgical treatment performed. No predictive factors for recurrence were identified in this series. Wide local excision with a negative margin of a least 1 cm is suggested as the treatment of choice. APR should be reserved for tumor not amenable to local excision or for palliative treatment of large obstructive lesion until effective adjuvant therapies are available.

Anorectal malignant melanoma

BACKGROUND

Great controversy exists with regard to the best surgical therapy for anorectal malignant melanoma.

MATERIALS AND METHODS

Between 1980 and 1996, 15 patients with anorectal malignant melanoma were treated. The recurrence pattern after therapeutic intervention and their survival were evaluated.

RESULTS

There were nine females and six males, their mean age was 66.3 years. At diagnosis their disease stages were: I (n=7), 11 (n=3) and III (n=5). Patients with stage I disease were treated with abdominoperineal resection (APR) (n=6) and local excision (n=1); their average tumour size and thickness were: 4.7 cm and 6.4 mm respectively; their median follow-up and disease-free survival were 11 months and 7 months respectively; their recurrence pattern was: local (n=6), inguinal (n=4) and distant (n=6). Those patients with stage II and III disease were treated with transverse colostomy (n=6); two of them received 50 Gy of radiotherapy and local excision plus interferon alpha-2b (n=2), all had progressive distant disease. Patients with stage I disease had a median survival of 12 months compared with 5 months for those with stages II and III (P=0.10). The overall 5-year survival was 0%.

CONCLUSION

The recurrence pattern in anorectal malignant melanoma is mainly at distant sites. The role of APR in maintaining local control over tumours larger than 4 cm or thicker than 5 mm remains elusive.

Anorectal melanoma. A 64-year experience at Memorial Sloan-Kettering Cancer Center

PURPOSE

Operative management of patients with anorectal melanoma is controversial. To formulate a rational approach to patients with this disease, we reviewed our experience from 1929 to 1993.

METHODS

Records of all patients treated at our center with anorectal melanoma from 1929 to the present were reviewed. Survival analyses were graphically displayed using the Kaplan-Meier product-limit method, and distributions were compared using the log-rank test. Fisher's exact test was used to compare groups with small sample sizes.

RESULTS

Survival for the entire group (n = 85) was poor, 17 percent at 5 years (median, 19 months). Among the 71 patients with resectable disease, the five-year, disease-free survival distribution of patients who underwent abdominoperineal resection (APR) was more favorable than that of patients who underwent local procedures only, although this was not statistically significant (27 percent vs. 5 percent, APR vs. local procedures, respectively; P = 0.11). However, those who had an APR were more likely to survive long term than those who did not (P < 0.05). All ten long-term survivors were women. Nine had undergone APR, and one had a wide local excision. Of the nine survivors following APR, eight had negative and one had positive mesenteric nodes. Median size of the primary tumor in survivors following APR was 2.5 cm, compared with 4.0 cm for patients who did not survive long term following APR.

CONCLUSIONS

APR should be considered in patients with localized anorectal melanoma, particularly those with smaller tumors and no evidence of nodal metastases.

Anorectal malignant melanoma has a poor prognosis

Clinicopathologic features and surgical treatment of 15 patients with primary anorectal malignant melanoma were studied retrospectively. There was a female preponderance (2:1). The median age was 66 years. Common initial symptoms were rectal bleeding (87%) and/or anal pain (33%); 25% of the melanomas were amelanotic. The maximum tumor size ranged between 0.8 and 8.4 cm (median 3.0 cm). Of the tumors evaluated histologically (n = 12), tumor thickness ranged from 0.9 to 11.3 mm (median 6.1 mm). All melanomas invaded at least into the subepithelial tissue (n = 8) and/or the submucosa of the distal rectum (n = 4), with extension into the internal anal sphincter (n = 5) and lamina propria (n = 3). Endoluminal ultrasound accurately demonstrated depth of invasion in 3 of 3 patients. Three (20%) patients with distant metastases at initial presentation had a mean survival of 8 mo; one of these primary melanomas measured 0.8 cm. Of 12 patients undergoing "curative" treatments--4 by abdominoperineal resection (APR) and 8 by local excision (LE), the incidence of loco-regional recurrence was similar (2/4 and 5/8). All these 7 patients with loco-regional recurrence developed distant metastases within 3 months. The mean survival was similar between APR and LE in the total group (25 mo vs 20 mo), in the decreased (27 mo vs 24 mo) and in those treated with a curative intent (29 mo vs 22 mo). There was no long-term survivor but four patients remained tumor-free up to 19 mo after APR (n = 1) or LE (n = 3).(ABSTRACT TRUNCATED AT 250 WORDS)

Anorectal malignant melanoma in Sweden. Report of 49 patients

Clinicopathologic features and prognosis of 49 patients with anal malignant melanoma were investigated in the total Swedish population between 1970 and 1984. Median age was 71 years (range, 50 to 87 years), and there was a female predominance (31 females, 18 males). The most common symptom at presentation was bleeding. The majority of tumors ranged between 2 and 5 cm in diameter and all invaded at least into the submucosa and/or the lamina propria. At diagnosis, one third of the patients had either regional or distant metastasis with a median survival of 5 months. The remaining patients were surgically treated with curative intent, either by abdominoperineal resection (APR) or local excision. Median survival was poor in both treatment groups (APR, 12 months; local excision, 13 months). Most patients died with distant metastasis. Our results confirm the opinion that APR offers no more curative potential than a more conservative surgical approach. However, tumor sizes were on average smaller in the group treated by local excision. This could indicate that, in the absence of known distant metastasis, radical surgery should be performed, particularly since local recurrences tended to be more common after a local excision.

The surgical treatment of anorectal malignant melanoma

The clinical presentation and surgical treatment of 21 patients with anorectal melanoma over a 44 year period have been analysed. During the first 24 years of this period total rectal excision was regarded as the treatment of choice and since then wide local excision. Two groups of patients emerge for comparison of the results of surgical treatment. There were no long-term survivors in either group and little difference between survival rates after either procedure. It was concluded that the change from radical to conservative surgery for anorectal melanoma has made no difference in terms of survival and the possible advantages of this change have been discussed.