The surgical treatment of anorectal malignant melanoma

Effect of surgical treatment for anorectal melanoma: a propensity score-matched analysis of the Surveillance, Epidemiology, and End Results programme data

OBJECTIVE

Anorectal melanoma (AM) is a rare but aggressive tumour with limited information in the existing literature. This study aimed to assess the effect of surgical treatment for AM and predict the prognosis of affected patients.

DESIGN

A retrospective cohort study.

SETTING

Data of patients diagnosed with AM between 1975 and 2016 in the USA were collected from the Surveillance, Epidemiology, and End Results (SEER) database.

PARTICIPANTS

This study enrolled a total of 795 patients with AM from the SEER database and the validation cohort comprised 40 patients with AM enrolled from Chinese institutes.

PRIMARY AND SECONDARY OUTCOME MEASURES

Overall survival (OS) and AM-specific survival (AM-SS).

RESULTS

A total of 795 patients with AM diagnosed between 1975 and 2016 were enrolled in this study. Data over the past four decades showed a trend of increase in incidence rate. A nomogram based on a multivariate Cox regression model was generated to predict AM-SS. The C-index of the nomogram was 0.74 (95% CI 0.71 to 0.77) on internal verification. In the validation cohort, the C-index of the nomogram was 0.72 (95% CI 0.68 to 0.76). The results of propensity score matching (PSM) analysis showed that patients who underwent surgical treatment achieved significant survival (OS: log-rank=17.41, p<0.001; AM-SS: log-rank=14.55, p<0.001). Patients who underwent surgery were stratified into local and extended surgery subgroups. AM-SS and OS were also compared after PSM, but the results were not significantly different between the two surgery subgroups (all p>0.05).

CONCLUSIONS

The nomogram based on the analysis of SEER data showed good performance in predicting OS and AM-SS. Patients with AM can benefit from surgery; however, extensive surgery and appendectomy may not improve AM-SS or OS.

Can transrectal ultrasonography distinguish anorectal malignant melanoma from low rectal adenocarcinoma? A retrospective paired study for ten years

BACKGROUND

Anorectal malignant melanoma (ARMM) and low rectal adenocarcinoma (LRAC) have some similarities in clinical behaviors, histopathological characteristics and ultrasonographic findings, diagnostic errors are common. By comparing the transrectally ultrasonographic features between the two tumors, we propose to provide more possibilities in differentiating them.

METHODS

The data of 9 ARMMs and 27 age- and gender-matched LRACs (the lower margin below the peritoneal reflection) in West China Hospital Sichuan University between April 2008 and July 2019 were retrospectively reviewed. The ultrasonic features between the two groups were compared.

RESULTS

Transrectal ultrasonography (TRUS) showed that the length of ARMM was shorter than that of LRAC (28.22 ± 12.29 mm vs. 40.22 ± 15.16 mm), and ARMM had a lower position than that of LRAC (the distance to anal verge was 50.78 ± 11.70 vs. 63.81 ± 18.73 mm). Unlike LRAC, the majority of ARMM in our study was confined to the intestinal mucosa/submucosa (66.67/25.93%) (P < 0.05).

CONCLUSIONS

Based on the data of our study, several ultrasonographic findings (length, invasion depth, and position) of ARMM were significantly different from LRAC. Accordingly, more attention should be paid to masses at anorectal junction with lower position, shorter length, and shallower infiltration depth. Instead of the most common tumor, LRAC, ARMM should be taken into account to avoid a misdiagnosis, which will result in a poorer prognosis.

Surgical treatment of anorectal melanoma: a systematic review and meta-analysis

Background

Anorectal melanoma is a rare neoplasm with a poor prognosis. The surgical approaches for anorectal melanoma can be categorized into local excision (procedures without lymph node removal and preservation of the rectum) and extensive resection (procedures with rectum and pararectal lymph node removal). The aim of this systematic review and meta-analysis was to compare the survival of patients who underwent extensive resection with that of patients who underwent local excision, stratifying patients according to tumour stage.

Methods

A literature review was performed according to PRISMA guidelines by searching MEDLINE/PubMed for manuscripts published until March 2021. Studies comparing survival outcomes in patients with anorectal melanoma who underwent local excision versus extensive resection were screened for eligibility. Meta-analysis was performed for overall survival after the different surgical approaches, stratified by tumour stage.

Results

There were 347 studiesidentified of which 34 were included for meta-analysis with a total of 1858 patients. There was no significant difference in overall survival between the surgical approaches in patients per stage (stage I odds ratio 1.30 (95 per cent c.i. 0.62 to 2.72, P = 0.49); stage II odds ratio 1.61 (95 per cent c.i. 0.62 to 4.18, P = 0.33); stage I–III odds ratio 1.19 (95 per cent c.i. 0.83 to 1.70, P = 0.35). Subgroup analyses were conducted for the time intervals (<2000, 2001–2010 and 2011–2021) and for continent of study origin. Subgroup analysis for time interval and continent of origin also showed no statistically significant differences in overall survival.

Conclusion

No significant survival benefit exists for patients with anorectal melanoma treated with local excision or extensive resection, independent of tumour stage.

Management of Noncutaneous Melanomas

Noncutaneous melanomas are rare subtypes of melanoma with high rates of metastatic disease and poor overall survival. One-third to one-half of cases are amelanotic, which may contribute to a delay in diagnosis. Immunohistochemistry staining with typical melanoma markers helps confirm the diagnosis. There is no standard staging system across mucosal melanomas. Elective nodal dissection is not recommended and there is a paucity of data to support use of sentinel lymph node biopsy. Mutational analysis should be routinely performed. Systemic therapy options include targeted inhibitors, immunotherapy, and cytotoxic chemotherapy, although further studies are needed to confirm their efficacy.

Anorectal melanoma – histopathological and immunohistochemical features and treatment

Anorectal melanomas should be characterized by location (anal, rectal and anorectal), color, size, shape and mobility and microscopically, by melanocyte subtypes, grade of melanin pigmentation, junctional changes in the squamous epithelium, atypical mitotic index, cellular atypia, inflammatory infiltrate, vascular and perineural invasion, sentinel lymph node, and anorectal parietal penetration. Anorectal melanomas must be staged by American Joint Committee on Cancer (AJCC) and/or TNM Classification of Malignant Tumours (TNM) criteria. As melanocytes can present with several shapes, sometimes the differential diagnosis with other tumors in this region may be difficult. Because of this, immunohistochemistry is mandatory to attain a precise diagnosis. This study is a report of 14 patients with anorectal melanoma, in whom histological examinations were remade and immunohistochemistry was performed with several markers for melanocytes and for other tumor cells of the anorectal region, properly establishing the diagnosis. The most rational surgery is the extended local resection, when the disease is restricted to the area or the abdominoperineal resection to advanced lesions. Regardless of the technique used, the results are always poor. The authors deny any efficacy of current radio and/or chemotherapy as part of treatment of anorectal melanoma. Target-therapy for metastatic disease has been considered a good strategy, but the results are still inconclusive.

Trends in the management of anorectal melanoma: A multi-institutional retrospective study and review of the world literature

BACKGROUND

Anorectal melanoma (ARM) is a rare disease with a poor prognosis. Evidence on optimal treatment is limited and surgical management varies widely. We hypothesized that the frequency of abdominoperineal resection used as primary treatment of ARM has decreased over the past several decades.

AIM

To update our understanding of outcomes for patients with ARM and analyze management trends around the world.

METHODS

This is a multi-institutional, retrospective study of patients treated for ARM at 7 hospitals. Hospitals included both large, academic, tertiary care centers and smaller, general community hospitals. Using prospectively maintained institutional tumor registries, we identified 24 patients diagnosed with ARM between January 2000 and May 2019. We analyzed factors prognostic for recurrence and survival. We then used Cox regression to measure overall survival (OS) and melanoma-specific survival. We also performed a literature review to assess trends in surgical management and outcomes.

RESULTS

Of the 24 patients diagnosed with ARM, 12 (50.0%) had local, 8 (33.3%) regional, and 4 (16.7%) distant disease at diagnosis. Median time to recurrence was 10.4 mo [interquartile range (IQR) 7.5-17.2] with only 2 patients (9.3%) not developing recurrence following surgical resection. Median OS was 18.8 mo (IQR 13.5-33.9). One patient is still alive without recurrence at 21.4 mo from diagnosis; no other patient survived 5 years. Primary surgical management with abdominoperineal resection (APR) vs wide excision (WE) did not lead to differences in OS [hazard ratio = 1.4 (95%CI: 0.3-6.8)]. Review of the literature revealed geographic differences in surgical management of ARM, with increased use of WE in the United States and Europe over time and more frequent use of APR in Asia and India. There was no significant improvement in survival over time.

CONCLUSION

There is wide variation in the management of ARM and survival outcomes remain poor regardless of approach. Surgical management should aim to minimize morbidity.

Endoscopic diagnosis of primary anorectal melanoma

OBJECTIVE

The present study retrospectively analyzed case data from 12 patients diagnosed with anorectal melanoma, with the purpose of identifying key diagnostic features at endoscopy.

MATERIALS AND METHODS

Images from colonoscopy were reviewed for all patients in order to establish the endoscopic features of primary anorectal melanoma. For the patients whose colonoscopic examinations included endoscopic ultrasound, images were examined to characterize lesions and the depth of infiltration, the results of which were compared with pathological findings after operative resection.

RESULTS

At colonoscopy, superficial melanin pigmentation was identified in 10 patients with anorectal melanoma, with morphology including spots, patches, or sheets of pigmentation. In patients who underwent endoscopic ultrasound, lesions appeared as masses on the mucosal side with inhomogeneous or low-level internal echoes or ulcer-type lesions invading the muscularis propria. Lesions diagnosed as anorectal melanoma also demonstrated irregular margins and varying degrees of submucosal infiltration. Infiltration depth of melanoma via endoscopic ultrasound (EUS) was concordant with surgical pathology results in 100% of patients.

CONCLUSION

Colonoscopy combined with biopsy and subsequent pathological examination can accurately diagnose primary anorectal melanoma. Moreover, EUS is a reliable tool for assessing the depth of infiltration of this disease.

Prognostic factors in primary anorectal melanoma: a clinicopathological study of 60 cases in China

To investigate the clinicopathological features and prognostic factors of primary anorectal melanoma, we described the clinical presentations, histopathology, and prognosis of 60 cases in China. Patients' age ranged from 17 to 86 years, with a female-to-male ratio of 2.33:1. The prevalent anatomic site of tumor was the anorectum. The mean tumor thickness was 11.5 mm, and mean tumor size was 2.9 cm. Abdominoperineal resection was performed on 38 (63.3%) patients, whereas wide local excision was performed on 22 (36.7%) patients. Thirty-three (55.0%) patients were pathologically confirmed to have lymph node metastasis, and 9 (15%) patients had clinically distant metastasis at diagnosis. Histologically, epithelioid cell (91.7%) was the predominant cell type, followed by spindle (31.7%), pleomorphic (25.0%), and small round cell (5.0%). Solid sheet, nest, pseudopapillary, and pseudoalveolar growth patterns were noted in 45 (75.0%), 22 (36.7%), 13 (21.7%), and 6 (10.0%) cases, respectively. After a median follow-up of 44 months, the 5-year disease-specific survival rate was 33.3%. Age, tumor size, depth of invasion, tumor thickness, lymphatic metastasis, and lymphovascular and perineural invasion were significantly correlated with survival in univariate analysis. Multivariate analysis revealed that age greater than 70 years and tumor invasion beyond deep muscular layer/sphincter ani externus were independent poor prognostic factors. As the largest single-institution study of anorectal melanoma in an Asian population, we concluded that anorectal melanoma is a rare and lethal malignant neoplasm with morphologic diversity. Large population-based studies are still needed to establish an efficient staging system in evaluation of prognosis and facilitation of treatment for anorectal melanoma patients.

Primary Anorectal Malignant Melanoma: Report of two Cases

Primary anorectal malignant melanoma is a fairly uncommon but highly malignant disease. It is sometimes mistaken for benign conditions such as hemorrhoids or rectal polyps. Here we describe two cases of primary malignant melanoma of the rectum: in one patient a wide local excision (WLE) was performed and in the other an abdominoperineal resection (APR), both with curative intent. Both patients developed systemic recurrences and died of their disease at 24 and 10 months, respectively. In conclusion, the prognosis of anorectal melanoma is poor, irrespective of surgical treatment. WLE is the first choice for primary anorectal melanoma, while APR should be reserved for those cases where complete transrectal tumor resection is technically impossible.

Abdominoperineal resection provides better local control but equivalent overall survival to local excision of anorectal malignant melanoma: a systematic review

OBJECTIVE

To determine whether the extent of surgery is associated with survival in anorectal malignant melanoma (ARMM).

BACKGROUND

ARMM is a rare and highly malignant neoplasm with unfavorable prognosis. The optimal surgical management, abdominoperineal resection (APR) or local excision (LE), has been long debated, but conclusive evidence has not been obtained.

METHODS

A comprehensive electronic literature search was performed to identify studies evaluating survival between APR and LE for ARMM. The main outcome measures were overall survival, relapse-free survival, and local recurrence. A meta-analysis was performed using the random-effects models to calculate the odds ratios (ORs) and 95% confidence intervals (CIs).

RESULTS

Thirty-one studies, with a total of 1006 patients [544 (54.1%) APR and 462 (45.9%) LE], were included. Meta-analyses showed that overall survival (OR, 1.14; 95% CI, 0.74-1.76; P = 0.54) and relapse-free survival (OR, 0.95; 95% CI, 0.43-2.09; P = 0.89) did not differ significantly between the APR and LE groups. APR significantly reduced local recurrence compared with LE (OR, 0.18; 95% CI, 0.09-0.36; P < 0.00001).

CONCLUSIONS

Although several limitations, such as inclusion of only retrospective studies with relatively small sample size and selection biases for surgical procedure, are involved, this meta-analysis suggested that APR has no survival benefit; however, APR confers better local control than LE. Given that local failures after LE could be managed by salvage surgery, minimizing morbidity and maximizing quality of life should be the focus in surgical treatment of ARMM.

Preliminary Suggestion about Staging of Anorectal Malignant Melanoma May Be Used to Predict Prognosis

PURPOSE

Anorectal malignant melanomas (AMM) are rare and have poor survival. The study aims to evaluate the clinicopathologic characteristics and outcomes of patients with AMM, and to devise a staging system predictive of survival outcome.

MATERIALS AND METHODS

This was a retrospective study of 28 patients diagnosed with, and treated for AMM. Patients classified by clinical staging of mucosal melanoma (MM) were reclassified via rectal and anal TNM staging. Survival outcomes were compared among patients grouped by the three different staging systems.

RESULTS

The three staging systems were equated with similar figures for 5-year overall survival (OS) and 5-year disease-free survival (DFS) of patients diagnosed with stage I disease. Patients (n=19) diagnosed with MM stage II disease were reclassified by rectal TNM staging into three subgroups: IIIA, IIIB, and IIIC. For these patients, both 5-year OS and 5-year DFS differed significantly between the subgroups IIIA and IIIC (OS: IIIA vs. IIIC, 66.7% vs. 0%, p=0.002; DFS: IIIA vs. IIIC, 51.4% vs. 0%, p < 0.001).

CONCLUSION

The accuracy of prognosis in patients diagnosed with AMM and lymph node metastasis has improved by using rectal TNM staging, which includes information regarding the number of lymph node metastases.

The clinical features and optimal treatment of anorectal malignant melanoma

Anorectal malignant melanoma (AMM) is a very rare and aggressive disease. The purpose of this article is to review the clinical features of AMM, to understand treatment options, and optimal therapy by reviewing pertinent literature. Traditionally an abdominoperineal resection (APR) sacrificing the anal sphincter has been performed for radical resection of cancer, but recently, wide excision of AMM is attempted since quality of life after surgery is an important issue. Some authors reported that there was no difference in five-year survival between the patient who underwent an APR and wide excision. The goal of both APR and wide excision was to improve survival with R0 resection. Adjuvant chemoradiation therapy can be performed to achieve an R0 resection. AMM shows very poor prognosis. At this time, research on AMM is insufficient to suggest a treatment guideline. Thus, treatment options, and a therapeutic method should be selected carefully.

Anorectal melanoma

Anorectal melanoma is a disease that can be difficult to diagnose because of its unclear presentation. After diagnosis, the main treatment available is surgical resection. Sentinel lymph node mapping has an unclear role in its management. Adjuvant therapy has long been recommended; however, there are no strong data to support its use. Prognostic factors to help gauge survival are also not clear; nevertheless, there is a strong association between stage of disease and histologic perineal invasion. Anorectal melanoma is a very rare disease with a dismal prognosis.

A Systematic Review of Prognosis and Therapy of Anal Malignant Melanoma: A Plea for More Precise Reporting of Location and Thickness

Anal malignant melanoma (AMM) is a rare tumor with poor prognosis. We performed a systematic review of reports on wide local excision (WLE) and abdominoperineal resection (APR) for treatment of AMM in an attempt to define a precise set of reporting measures for outcomes of treatment of AMM. A systematic review of the literature was performed. Demographic data, surgical treatment, pathology, and survival rates were recorded. We compared WLE versus APR in terms of the overall survival time, the disease-free survival, and overall survival at 60 months. Twenty-one reports met the inclusion criteria. Notably, of these, 10 did not specify thickness of the primary melanoma. Interestingly, groin lymph node status was described in 19 of 21 reports, whereas location was specified in only 12 papers and thickness (depth in mm) in only 11. The median survival times of patients undergoing WLE (n = 324) and those undergoing APR (n = 369) are comparable (20 and 21 months, respectively). The mean median survival at 60 months was 15 per cent for WLE and 14 per cent for APR. The mean disease-free survival at 60 months was found to be 10 per cent for WLE and 6 per cent for APR. Patient selection for such a rare neoplasm yields very similar outcomes for both conservative and radical treatments. There is a wide variation in the reporting of both clinical and treatment outcomes. More uniformity of reporting of pathologic features and node status is essential before rational assessment of results can be done.

Anorectal melanoma: diagnosis and treatment

An increase in the incidence of anorectal melanoma has recently been noted in the United States. Anorectal melanoma is an uncommon and lethal condition, with a median survival of <20 months. Unfortunately, nonspecific symptoms also attributable to common and benign conditions (eg, hemorrhoids) cause significant delay in its diagnosis. Although it has not been validated by clinical trials, abdominoperineal resection has historically been the treatment of choice for this disease. However, for the past 2 decades, a lack of clear survival benefit has led to a shift toward less-mutilating wide local excisions. Controversy still exists regarding the benefit of radiation therapy and chemotherapy. Furthermore, the value of nodal surgery in anorectal melanoma is unclear. In this article, we review the history and current status of management of anorectal melanoma, with a particular focus on surgical controversies and challenges in optimizing survival.

Treatment outcomes of anorectal melanoma

Purpose

An anorectal melanoma (AM) is a very rare tumor. However, sufficient data supporting effective surgical options for the disease do not exist. This retrospective review aimed to analyze treatment outcomes for an AM.

Methods

From June 1999 to December 2008, we retrospectively reviewed a prospectively collected consecutive series of 19 patients who had undergone a surgical resection for an AM at a single institute. Surgical method and clinicopathological factors were analyzed.

Results

The median age was 61.4 years (range, 46 to79 years). Main symptoms were an anal mass, hematochezia, perianal pain, tenesmus, fecal incontinence, and bowel habit change. The average duration of symptoms before diagnosis was 7.8 months (range, 1 to 36 months). S-100 and HMB-45 were positive in all patients, even in non-melanin pigmentation. There were 12 abdominoperineal resections (APRs) and 7 wide local excisions (WEs). The APR showed longer overall survival when compared with the WE (64.1 months vs. 10.9 months, P < 0.001). No patients who underwent a WE survived more than 13 months.

Conclusion

A high index of suspicion is necessary to establish the diagnosis for an AM in patients with anal symptoms, and S-100 and HMB-45 can be useful markers for an AM. Even with the small number of cases and the short follow-up, our data suggest that an APR for an AM may provide longer survival than a WE.

Anorectal melanoma

The authors review the epidemiologic, clinicopathologic, and molecular features of anorectal melanoma, and discuss the differences between this uncommon and lethal disease and the more common and curable cutaneous form. Observations regarding outcomes after surgical resection will also be discussed, as well as predictors of survival and the use of adjuvant therapies. The recent discovery that the KIT oncogene may be aberrantly activated in a subset of patients with anorectal melanoma creates a realm of possibility for the development of targeted molecular therapy. Melanoma of the anorectum is an extremely rare tumor that is often difficult to diagnose. Its surgical management is controversial, and the prognosis remains poor.

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.

Malignant melanoma of the anorectum--a rare entity

OBJECTIVE

Primary anorectal melanoma is a rare entity with a poor prognosis accounting for approximately 0.1-4.6% of anal tumours and 0.5-1.6% of all melanomas. Almost 60% of patients have already disseminated disease at initial diagnosis.

METHOD

We report four cases of anorectal melanoma treated at our department from November 2006 to September 2008, as well as a review of the literature.

RESULTS

There were two females and two males, of median age 69 years (range: 59-81 years). Most frequent complaints were rectal bleeding and/or anorectal pain. Three of our four patients had amelanotic melanomas. We found the positive expression of S-100 protein and HMB-45 in two patients and melanin A cells in one case. Abdominoperineal resection was performed in two patients, colostomy in one patient and a wide local excision also in one case. Three patients died on account of dissemination of melanoma, one patient is still alive.

CONCLUSION

Anal melanoma remains a deadly problem. Clear guidelines for the therapy of anorectal melanoma have not been established. This mainly results from the rarity of this tumour. Treatment is based on retrospective studies, which report a limited number of cases.

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.

Primary anorectal malignant melanoma: two case reports and review of the literature

Anorectal melanoma is a very rare tumor with poor prognosis because of delay in diagnosis. It is often mistaken for benign conditions such as hemorrhoids or rectal polyps. Surgical treatment ranges from local excision to radical abdominoperinal resection. Herein, we report 2 cases of anorectal malignant melanoma and further review the diagnostic and therapeutic approaches in light of the pertinent literature.

Melanoma of the anal canal: a case series

PURPOSE

Anal melanoma is an uncommon and aggressive cancer. Different surgical modalities have been used in managing the disease with no clear evidence to favor one approach over another.

METHODS

The medical records of patients with anal melanoma treated at the H. Lee Moffitt Cancer and Research Institute between 1987 and 2004 were reviewed. Published anal melanoma studies, including more than ten patients with outcome data, also were reviewed.

RESULTS

Twelve patients were identified (8 percent of all cancer of the anal canal). Nine were females with a median age of 67 (range, 27-86) years. Four patients had nodal involvement, and one had bone metastases at the time of diagnosis. Five patients had abdominoperineal resection, and six had local excision. Adjuvant radiation therapy with or without interferon was used. Five of the 11 patients without metastatic disease relapsed or died within the first year of diagnosis (4 had local excision and 1 had abdominoperineal resection). Median time to relapse was 6.5 (range, 4-31) months. The liver was the most common site for relapse. Only one patient treated with local excision followed by interferon was a long survivor (no evidence of recurrence at 54 months).

CONCLUSIONS

Anorectal melanoma is a rare and challenging disease. The preoperative staging influences the treatment schedule. In the absence of strong survival benefit of abdominoperineal resection in managing the nonmetastatic form of the disease, it is reasonable to consider local excision as the initial treatment of choice. Adjuvant radiation therapy is well tolerated and is promising in improving locoregional control.

The role of abdominoperineal resection as surgical therapy for anorectal melanoma

OBJECTIVES

1) Characterize changes in the surgical treatment of anorectal melanoma over time. 2) Determine if the extent of surgical resection is associated with outcome. 3) Identify prognostic factors correlating with survival.

SUMMARY BACKGROUND DATA

Although early data suggested improved survival in patients undergoing abdominoperineal resection (APR) for primary anorectal melanoma, such an aggressive approach may be unwarranted as distant relapse rates are high. We have seen a trend toward less aggressive surgical treatment of the local disease over the past 20 years.

METHODS

A retrospective review was performed of all patients with anorectal melanoma treated at our institution between 1984 and 2003. Extent of primary resection and pathologic factors were studied.

RESULTS

Forty-six patients underwent a curative resection with a median follow-up of 29 months, and 5-year disease-specific survival (DSS) rate of 35%. While patient and tumor characteristics remained similar, there was a dramatic shift in surgical treatment toward less radical procedures. Prior to 1997, the majority of patients (15 of 21, 71%) underwent APR. After 1997, the majority of patients (21 of 25, 84%) underwent local excision (LE) (P < 0.0001). Local recurrence was noted in 11 of 46 (24%) patients: 4 of 19 (21%) who underwent APR and 7 of 27 (26%) who underwent LE (P = not significant). Five-year DSS was similar: 34% following APR and 35% following LE. Tumor perineural invasion (PNI) was the only factor identified as an independent predictor of worse outcome (P = 0.01).

CONCLUSION

The extent of surgical treatment is not associated with outcome in primary anorectal melanoma. Therefore, LE of the primary tumor is recommended when technically feasible. The presence of PNI is an important prognostic factor and should be considered in future clinical trials.

Management of Less Common Tumors of the Colon, Rectum, and Anus

The majority of colorectal and anal malignancies are adenocarcinomas and squamous cell cancers, respectively. Despite the predominance of these neoplasms in these locations, rare histiotypes of the colon, rectum, and anus do occur. These histotypes include but are not limited to lymphoma, melanoma, diffuse cavernous hemangioma, and sarcomas, such as leiomyosarcoma or Kaposi's sarcoma. These tumors often present challenges to clinicians with respect to diagnosis, staging, management, and pathology because of their unfamiliarity. A Medline search using "colon," "rectum,""anus," "lymphoma," "melanoma," "diffuse cavernous hemangioma," "squamous cell carcinoma," "carcinoid," "sarcoma," "leiomyosarcoma," "Kaposi's sarcoma," "Paget's disease," "Bowen's disease," and "basal cell carcinoma" as key words was performed as well as a cross-referencing of the bibliography cited in each work. Rare tumors of the colon, rectum, and anus present diagnostic and management dilemmas for clinicians. Because of their infrequency and poor prognosis, the optimal management of these tumors is controversial. For some histotypes, such as squamous cell carcinoma and carcinoids of the rectum, treatment depends on location and size of the tumor. For uncommon anal lesions, such as Bowen's disease, Paget's disease, and basal cell carcinoma, wide local excision (WLE) with negative margins is the standard of care. For other lesions such as anorectal melanoma or leiomyosarcoma, abdominal perineal resection versus WLE is still being debated. Because the optimal treatment of these tumors is still unclear, we recommend a multidisciplinary approach including a surgeon, primary care physician, medical oncologist, radiation oncologist, and pathologist to offer the patient the best outcome.

Wide local excision or abdominoperineal resection as the initial treatment for anorectal melanoma?

BACKGROUND

Anorectal melanoma (AM) is a rare tumor with a poor prognosis. Treatment with abdominoperineal resection (APR) over wide local excision (WLE) is still debated. This study aimed to compare median survival of WLE and APR in patients with AM.

METHODS

A systematic review of the literature was performed. Only series that allowed calculation of median survival were included.

RESULTS

Fourteen studies met inclusion criteria. Average median survival of stage I WLE patients (N=34) and stage I APR patients (N=31) was 44 and 22 months, respectively (P=.001). For stage II patients, 7 underwent WLE, and 10 underwent APR with an average median survival of 36 and 14 months, respectively (P=.19).

CONCLUSIONS

This study identified no stage-specific survival advantage to APR in favor of AM. Given that WLE is a more limited intervention associated with at least comparable survival, we propose that it be considered the initial treatment of choice for AM.

A comparison of wide local excision with abdominoperineal resection in anorectal melanoma

Anorectal melanoma is a rare condition and its surgical management is controversial. Seventeen large case series from over the past 10 years were reviewed. The survival of patients treated by either abdominoperineal resection (APR) or wide local excision (WLE) was analysed according to the stage of the disease. Comparison of the survival of patients who underwent APR with those who underwent WLE showed no statistically significant advantage for either procedure in patients at all disease stages. APR should therefore only be performed when local excision is not possible or for palliative purposes.

Surgical management of primary anorectal melanoma

BACKGROUND

This aim of this study was to analyse outcome after surgery for primary anorectal melanoma and to determine factors predictive of survival.

METHODS

Records of 40 patients treated between 1977 and 2002 were reviewed.

RESULTS

Twelve men and 28 women of mean age 58.1 (range 37-83) years were included in the analysis. Overall and disease-free survival rates were 17 and 14 per cent at 5 years. Median overall survival was 17 months and disease-free survival was 10 months. The 5-year survival rate was 24 per cent for patients with stage I tumours, and zero for those with stage II or stage III disease. There was no significant difference in overall survival after wide local excision (49 and 16 per cent at 2 and 5 years respectively) and abdominoperineal resection (33 per cent at both time points). In patients with stage I and stage II disease, there was a significant association between poor survival and duration of symptoms (more than 3 months), inguinal lymph node involvement, tumour stage and presence of amelanotic melanoma.

CONCLUSION

Anorectal melanoma is a rare disease with a poor prognosis. Wide local excision is recommended as primary therapy if negative resection margins can be achieved.

Overview of anal cancer for the surgeon

Cancers of the anal canal represent a diverse group of pathology and require a multidisciplinary approach for treatment. For the most common anal canal cancer, anal SCC, the primary therapy is CMT with systemic chemotherapy and radiation. The surgeon plays a key role in the diagnosis and follow-up after treatment, with surgical intervention reserved for residual or recurrent disease. The overall prognosis for this disease is favorable. For anal adenocarcinoma, aggressive surgical resection remains the mainstay of therapy, with radiation therapy and chemotherapy used to aid in local disease control and for treatment of metastatic disease. A high rate of distant failure in this disease is responsible for the poor long-term prognosis. Anorectal melanoma has a high rate of distant failure and a poor overall survival rate. Surgical intervention is focused on local disease control with preservation of sphincter function. The biggest improvements in survival for this disease will come with more effective systemic therapy.

What is the best surgical treatment for anorectal melanoma?

BACKGROUND AND AIMS

This study compared outcome following the two common surgical procedures for anorectal melanoma: wide local excision and abdominal perineal resection. We also examined the utility of endoluminal ultrasound to guide therapy.

PATIENTS AND METHODS

Records of 19 patients surgically treated at our institution were studied. In addition to type of surgical procedure, we noted age, metastatic disease spread, sphincter involvement, tumor size and thickness, and mode of diagnosis. Survival after diagnosis and after recurrence of disease were also recorded. Ultrasound was used in seven, with the lesion delineated in six (all had therapy guided by the ultrasound). Regarding surgery ten had wide local excision, seven had abdominal perineal resection, and two had other procedures.

RESULTS

The most common sites of recurrence were distant in 31.6% and regional lymph nodes in 26.3%. Mean survival after recurrence was 13 months (range 5-29). Two patients who had wide local excision are disease free and alive 135 and 29 months after diagnosis. Neither surgical treatment conferred obvious benefit on survival.

CONCLUSION

Ultrasound can guide management by delineating lesions amendable to wide local excision. Since the mortality rate is high, wide local excision offers the advantage of avoiding a permanent colostomy and should be considered the procedure of choice when excision is feasible.

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.

Anal neoplasms

A common theme in most anal neoplasms appears to be a delay in diagnosis due to confusion with more common, benign conditions. Thus, the clinician must maintain a high index of suspicion when evaluating lesions of the anal canal and margin. The use of primary chemoradiation for SCC of the anal canal has resulted in equivalent, if not superior, local control and survival compared with radical surgery, and results in sphincter preservation in over two thirds of cases. Nevertheless, abdominoperineal resection still plays an important role in salvage of treatment failures, and also for patients who are unlikely to tolerate chemoradiation or have pre-existing impaired continence. Recent studies indicate that variations in chemotherapeutic agents and radiation technique might potentially produce even better results. The prognosis for anorectal melanoma, as well as for small cell and undifferentiated tumors, continues to be poor. Fortunately, these are relatively rare tumors.

Anorectal melanoma metastatic to the breast

Anorectal melanoma is an extremely rare malignancy with poor prognosis. Patients generally present with a sensation of mass and rectal bleeding, which is usually attributed to hemorrhoids or polyps. It can not be diagnosed early because of these benign symptoms, so it is bulky at the time of presentation. Despite aggressive surgery, 5-year survival is less than 10%. We present a case of inoperable anorectal melanoma which metastasized to the left breast and abdominal lymph nodes. We also briefly reviewed the appropriate literature, emphasizing the diagnostic and therapeutic approaches.

Malignant melanoma of the mucous membranes: a review of 119 cases

BACKGROUND

Melanomas arising from the mucous membranes lining the respiratory, digestive, and genitourinary tracts are rare. Women are more commonly affected than are men, mainly because there is no male counterpart for vulvovaginal lesions. The mainstay of therapy is surgery, with little current use of adjuvant modalities in primary therapy. These lesions usually are advanced at initial presentation; consequently, the prognosis is poor, with 5-year survivals well below 50% in most series.

METHODS

One hundred and nineteen patients with primary mucosal melanoma were reviewed. They represented 1.1% of the 10,393 melanoma patients seen at Duke University between 1970 and 1995. All data were obtained from the patients' clinic charts and computerized databases.

RESULTS

There were 43 tumors arising from the head and neck region, 46 from the urogenital tract, and 30 from the anorectum. A female predominance was observed, with a female-to-male ratio of 2.7:1. All but five of the patients underwent resection with curative intent. Regional or distant metastases, or both, were encountered in 36 patients at the time of presentation. In patients with head and neck and urogenital tumors, local recurrences accounted for most of the treatment failures, whereas systemic recurrences were more common with tumors arising in the anorectum. The age and gender of the patient, anatomic site of origin of the tumor, clinical stage at initial presentation, and ulceration of the primary all clearly affected prognosis. Overall, the probabilities of being alive 1, 5, and 10 years after diagnosis were 80%, 29%, and 15%, respectively.

CONCLUSIONS

Widely accepted classification systems are needed so that results from separate institutions can be compared adequately. Multi-institutional trials could help in delineating standardized therapeutic protocols and in establishing the potential roles of emerging modalities in the treatment of this subtype of melanoma.

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.

Synchronous anorectal malignant melanoma and rectal adenocarcinoma: report of a case

BACKGROUND

Synchronous neoplasms of the rectum are an uncommon condition. The situation becomes more rare when tumors are of different origin. To the authors' knowledge, synchronous anorectal melanoma and adenocarcinoma of the rectum have not been reported in the literature before.

METHODS AND RESULTS

A 67-year-old female patient with synchronous anorectal malignant melanoma and adenocarcinoma of the rectum is described. She had preoperative colonoscopic diagnosis. The different neoplasms' origin was histologically proven. Surgical management consisted of abdominoperineal resection of the rectum. Postoperatively, the patient received adjuvant chemotherapy of six cycles duration. At present, the patient has completed 32 months of follow-up. There is no evidence of recurrent disease or distant metastases.

CONCLUSION

Review of the literature confirms the rarity of anorectal malignant melanoma. On the other hand, the rectum represents the most common site for development of colonic adenocarcinoma. We were unable to trace synchronous presentation of these two tumors. Prognosis should be defined by the most malignant neoplasm; therefore, management should be focused on treating the melanoma.

Anorectal melanoma in The Netherlands: a report of 63 patients

A retrospective analysis was performed of the clinical features and results of surgical treatment modalities of 63 cases of anorectal melanoma collected in The Netherlands. Most tumours presented in an advanced stage due to the obscure location and lack of specific symptoms. There were 34 patients with clinical stage I disease who were treated by either local sphincter-saving surgery (n=16) or who had undergone an abdominoperineal resection (APR) (n=18). We could not find a survival advantage for either one of these two treatment modalities. However, after a local procedure far more local recurrences were seen (12:1), but this did not influence the clinical course of these patients, as they often rapidly succumbed to distant metastases. It is concluded that, in the future, patients presenting with an anorectal melanoma should be treated with a sphincter-saving surgical approach whenever possible.

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.

Primary malignant melanoma of the rectum

We present a case of primary malignant melanoma arising in the rectum of a 71-year-old woman who had presented with intermittent rectal bleeding following bowel movement 2 months previously. Digital and sigmoidoscopic examination of the rectum revealed a 3 x 2 x 1 cm exophytic tumor with a granular surface in the rectum 35 mm from the dentate line. No increased pigmentation was detected. Biopsy revealed degenerated mucosa accompanied by severe infiltration of inflammatory cells, but no malignant cells. The tumor and normal mucosa surrounding the tumor was excised 12 days after the biopsy. Light microscopy revealed the tumor to consist of malignant melanocytes and showed that the tumor was surrounded by normal mucosa. Immunohistochemical staining with antimelanoma antibody and HMB-45 substuntiated the diagnosis. Clinical and laboratory examination excluded the presence of melanoma at sites other than rectum. The patient refused an abdomino-perineal resection of the rectum and combination chemotherapy was performed. She died 18 months after the initial operation due to local recurrences and metastases to pelvic lymph nodes, liver, and lung.

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)

[Cancer of the anal canal; role of radiotherapy and combinations of chemotherapy and radiotherapy]

Carcinoma of the anal canal is a rare disease, more common in women than in men. The mean age distribution at presentation is about 60 years. The natural history is mainly loco-regional, distant metastases being uncommon. Histologically, most cancer are of the squamous cell type of different keratinization. The pre treatment evaluation is mainly performed by methodical clinical examination. There is no widely accepted staging system for these tumours. Three statistically significant prognostic factors are admitted: tumour size, regional nodal involvement and histological grade. The french school (Tenon, Institut Gustave Roussy, Institut Curie, Lyon) and the experience at the "Princess Margaret Hospital" at Toronto have shown that irradiation of these tumours is an adequate therapy. In Europe, irradiation has always played a more important role in the therapy of these tumours, than in North America where surgery was often preferred as the initial therapy. With the introduction of combined modality treatment, the use of pre-operative concomitant radiochemotherapy, in North America, has again changed the treatment policy towards a conservative radiotherapeutic approach. The present study analyses the modalities and the results from radiation therapy alone and the preliminary results from concomitant irradiation and chemotherapy.

Primary malignant melanoma of the rectum

The diagnosis of a primary rectal malignant melanoma has been the subject of considerable argument for many years, principally on the grounds that extension from a primary anal lesion was often impossible to exclude. This paper provides evidence that certain melanomas can be recognized as primary rectal tumours, not only from careful anatomical assessment of the site of the tumour, but also by showing that they arise on a background of benign melanocytic proliferation in the rectal mucosa. The clinical presentation of these lesions, their possible mechanism of origin and their treatment is discussed.

Melanosis of the esophagus. An endoscopic, histochemical, and ultrastructural study

Endoscopic, histological, and ultrastructural features of 21 cases of esophageal melanosis are described. These cases were detected during 1000 consecutive routine upper gastrointestinal endoscopies. Staining characteristics and ultrastructure of the pigment contained in the endoscopically visible lesions were found to be similar to those of true melanin.

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.

Current status--perianal and anal canal neoplasms

A large variety of neoplasms are found in the anal canal and perianal region. Most are distinctly uncommon and may, therefore, pose the question of suitable therapy. For some neoplasms, the treatment of choice is clear cut, while for others it is controversial. Certainly for squamous cell carcinoma of the anal canal, there has been a major rethinking of the treatment of choice. This review highlights the types of lesions found in the anal region and the current status regarding their appropriate treatment.