What is the best surgical treatment for anorectal melanoma?

Surgical Management of Primary Anorectal Melanoma: Is Less More?

PURPOSE

Ano-uro-genital (AUG) Mucosal Melanoma UK guidelines recommended a less radical surgical strategy for anorectal melanoma (ARM) where possible. We report our experience of ARM consistent with that approach including clinical presentation, intervention undertaken and prognosis.

METHODS

We present a retrospective study of 15 consecutive patients with ARM surgically treated between November 2014 and April 2023. Patients were divided into the two surgery types: wide local excision (WLE, n = 9) and abdominoperineal resection (APR, n = 6). Data on demographics, diagnosis, treatment and oncological outcomes were assessed between the groups.

RESULTS

The mean age was 65.3 ± 17.4 years and 6 (40.0%) were female patients. Nine patients (60.0%) were diagnosed with stage I and six patients (40.0%) with stage II disease. R0 margins were achieved in all cases. The overall mean length of stay was lower following WLE compared to APR (2.6 ± 2.4 days versus 14.0 ± 9.8 days, p = 0.032). Two complications were observed in the WLE group compared to four complications after APR (p = 0.605). Five patients (55.5%) developed local/distant recurrence in the WLE group compared to three patients (50.0%) in the APR group (p = 0.707), with a median overall survival of 38.5 (12-83) months versus 26.5 (14-48) months, respectively.

CONCLUSIONS

Achieving clear margins by the least radical fashion may have equivalent oncological outcomes to radical surgery, potentially reducing patient morbidity and preserving function. In our experience, the surgical management of ARM consistent with the 'less is more' approach adhering to AUG guidelines has acceptable outcomes.

Organ preservation in anorectal melanoma: A tempting challenge-a case report

Melanoma arising from melanocytes is an uncommon neoplastic lesion, with rare occurrences in anorectal mucosa. While mucosal melanomas constitute a small portion of all melanomas, anorectal cases are even rarer and present with aggressive behavior and poor prognosis. Surgical management is central, with evolving debates regarding optimal approaches. We present a case of a 60-year-old woman with anorectal melanoma. She complained of rectal bleeding and weight loss. Clinical examination and pelvic magnetic resonance imaging revealed a 3-cm budding lesion on the anterior rectal wall. Colonoscopy identified a pedunculated anorectal tumor of 3 cm, situated 4 cm from the anal margin. A biopsy led us to a malignant lesion: anorectal melanoma. Pelvic imaging displayed a localized tumor, prompting wide local excision with millimetric negative margins. These resection margins were estimated insufficient, even in front of R0 resection. Thus, and after multidisciplinary discussion, we opted for abdominoperineal resection after wide local excision. Lymph nodes were biopsied, confirming no residual tumor. Follow-up exhibited no recurrence at 1 year. Our case emphasizes the pivotal role of surgical strategy in managing anorectal melanoma, challenging the paradigm of organ preservation. Despite therapeutic progress, surgery remains integral, contributing to improved outcomes and addressing the metastatic potential inherent to this disease.

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.

Clinical and oncological outcomes of surgery in Anorectal melanoma in Asian population: A 15 year analysis at a tertiary cancer institute

INTRODUCTION

Anorectal malignant melanoma (ARMM) is an aggressive malignancy with dismal prognosis and a 5-year survival rate less than 20% in most of the previous studies. The ideal surgical treatment has still remained controversial. This retrospective study aims at analysing the outcome in patients with ARMM treated with curative surgical resection.

PATIENTS AND METHODS

This is a retrospective study of 38 patients of stage I anorectal malignant melanoma treated with curative surgical resection at our tertiary cancer institute.

RESULTS

WLE (Wide Local Excision) was carried out in 12 patients and APR (abdominoperineal resection) was done in 26 patients. The median overall survival of the entire group in this study was 20 months. Although the median overall survival of WLE patients was higher than those with APR (37 months versus 16 months, respectively), this was not a statistically significant event (P=0.317). The 1-, 2-, 3-, 5-year survival rates were similar with both APR and WLE with no significant difference in the 5-year survival rate (P=0.816); overall 5-year survival rate of just 13%. There were 3 long-term survivors in this study group who survived for more than 10 years.

CONCLUSION

Most patients ultimately succumb to the disease regardless of the management. Both APR and WLE have significant roles in the management depending on the subset of patients selected. Local treatment should be preferred wherever possible. Abdominoperineal resection should be offered in nodal disease or in a recurrent setting.

Malignant Melanoma of Anorectum: Two Case Reports

Malignant melanoma of the anorectum is a rare disorder. Patients often present with local symptoms similar to benign diseases. The prognosis is very poor, and almost all patients die because of metastases. We report 2 female patients with unremarkable histories. Both of them received previous operations before visiting our center after they were diagnosed with anorectal malignant melanoma. One case underwent abdominoperineal resection and postoperative chemotherapy. The other had been treated with ultralow anterior resection followed by immunotherapy.

Primary anorectal malignant melanoma with laparoscopic abdominoperineal resection: a case study and review of the relevant literature

ARMM is a disease with a poor prognosis. ARMM is often diagnosed at an advanced stage, and the 5-year survival rate of ARMM is < 20%. Although the number of case reports on ARMM is gradually increasing, the optimal treatment strategy for ARMM remains controversial. We report the case of an 81-year-old woman who had experienced bloody stool for 6 months before her diagnosis and who had been initially diagnosed with hemorrhoids. The pathological diagnosis of a biopsy specimen was malignant melanoma. Other examinations showed no evidence of lymph node or distant metastasis. Based on these results, laparoscopic abdominoperineal resection was performed. Three months later on her first follow-up examination, distant metastasis to the lung and liver was detected. Immunotherapy using Nivolumab was initiated to treat the recurrent disease. We reviewed the characteristics of a total of 1834 ARMM patients described in previous reports on ARMM for which the full text was available on PubMed. We experienced a case of ARMM. The prognosis of ARMM is still poor, regardless of the surgical procedure. Previous studies and our case report suggest that systemic therapy, such as immunotherapy using an anti-PD-1 ligand may be more important than reinforcement of local control for improving the prognosis of ARMM patients.

Less is more: A systematic review and meta-analysis of the outcomes of radical versus conservative primary resection in anorectal melanoma

INTRODUCTION

Anorectal melanoma (ARM) is a rare disease with a poor prognosis. There is no consensus as to the optimal primary surgical treatment for ARM, with advocates for both radical (abdominoperineal resection [APR]) and conservative strategies (wide local excision [WLE]). Here, we report a systematic review of studies comparing outcomes between these strategies.

METHODS

Studies comparing APR with WLE in patients with ARM were included, and a systematic review using the Grading of Recommendations, Assessment, Development and Evaluation methodology was performed. Outcomes deemed critical included overall survival, disease-free survival, local recurrence and quality of life.

RESULTS

Forty studies were identified, of which 27 were suitable for inclusion. Twenty-three studies compared overall survival between WLE and APR, with no difference in outcomes noted (risk ratio [RR]: 0.80, 95% confidence interval [CI]: 0.60-1.07, p = 0.13). Seven studies compared disease-free survival, with no difference in outcomes noted (RR: 1.08, 95% CI: 0.61-1.91, p = 0.79). A total of 19 studies compared local recurrence rates, with again no significant difference in outcomes noted (RR: 0.71, 95% CI: 0.44-1.14, p = 0.16). None of the studies identified reported quality of life-related outcomes.

CONCLUSION

There is no evidence to suggest that a radical primary surgical strategy improves outcomes in ARM. Therefore, given the well-documented morbidity associated with APR, WLE with regular surveillance for local recurrence should be the primary strategy in most patients.

Anal Cancer

Anal cancer is a rare cancer, comprising less than 5% of gastrointestinal tract malignancies. Diagnosis of anal canal cancer can be difficult given that presenting symptoms are similar to those of benign anorectal diseases. General surgeons who encounter suspected anal canal cancer need to have a good understanding of the anatomy of the anal canal, high index of suspicion for malignancy, and low threshold to biopsy lesions when indicated. This article discusses the most commonly encountered anal canal tumors, the evaluation of these tumors, and their management. The foundation for successful therapy includes timely diagnosis, accurate staging, and routine surveillance.

Multiple synchronous anorectal malignant melanoma coexisting with adenocarcinoma of the sigmoid colon

Primary anorectal malignant melanoma is an exceptionally rare neoplasm associated with poor prognosis. Anorectal malignant melanoma has been very rarely described with coexisting primary tumors of the colorectum. A 56-year-old female patient was admitted with a history of rectal bleeding. She had experienced increasing constipation and a sense of obstruction in the rectum for 6 months. Flexible rectosigmoidoscopy showed a large, pedinculated polypoid lesion extending from the anal canal to the rectum. She underwent a transanal local excision and was diagnosed with a melanoma of the anorectum with positive margins. Therefore, a formal abdominoperineal resection was performed. In addition to multiple synchronous anorectal malignant melanoma, we incidentally found another primary tumor in the proximal surgical margin of the resected specimen. Histopathologically, the lesion was an intramucosal adenocarcinoma of the sigmoid colon. Postoperatively, the patient received adjuvant chemotherapy of six cycles duration. At present, the patient has completed 18 months of follow-up.

Prolapsed anorectal melanoma

Anorectal melanoma is a rare malignancy of anorectal region. Often the diagnosis is delayed because of rare entity and confusion with benign disorders like haemorrhoids. There have been only a few cases reported and the optimum management for this condition is still in dilemma, however prompt diagnosis is essential for early curative surgery. We are presenting this case, due to rare presentation of prolapse of anorectal melanoma.

Primary amelanotic melanoma of the rectum mimicking adenocarcinoma

Patient: Male, 55

Final Diagnosis: Melanoma

Symptoms: Worsening constipation • tenesmus • weight loss

Medication: —

Clinical Procedure: Chemoradiation therapy

Specialty: Oncology

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 malignant melanomas: Retrospective experience with surgical management

AIM: To present the experience and outcomes of the surgical treatment for the patients with anorectal melanoma from the Cancer Hospital, Chinese Academy of Medical Sciences.

METHODS: Medical records of the diagnosis, surgery, and follow-up of 56 patients with anorectal melanoma who underwent surgery between 1975 and 2008 were retrospectively reviewed. The factors predictive for the survival rate of these patients were identified using multivariate analysis.

RESULTS: The 5-year survival rate of the 56 patients with anorectal melanoma was 20%, 36 patients underwent abdominoperineal resection (APR) and 20 patients underwent wide local excision (WLE). The rates of local recurrence of the APR and WLE groups were 16.13% (5/36) and 68.75% (13/20), (P = 0.001), and the median survival time was 22 mo and 21 mo, respectively (P = 0.481). Univariate survival analysis demonstrated that the number of tumor and the depth of invasion had significant effects on the survival (P < 0.05). Multivariate analysis showed that the number of tumor [P = 0.017, 95% confidence interval (CI) = 1.273-11.075] and the depth of invasion (P = 0.015, 95% CI = 1.249-7.591) were independent prognostic factors influencing the survival rate.

CONCLUSION: Complete or R0 resection is the first choice of treatment for anorectal melanoma, prognosis is poor regardless of surgical approach, and early diagnosis is the key to improved survival rate for patients with anorectal melanoma.

Abdominoperineal resection or local excision? a survival analysis of anorectal malignant melanoma with surgical management

Patients with anorectal malignant melanoma (AMM) generally have an unfavorable prognosis, and surgical managements are still in controversy. The purpose of this study was to evaluate the surgical treatment for AMM in China and to compare the survival of abdominoperineal resection (APR) and local excision (LE) in patients with AMM. Between 1995 and 2007, 54 patients managed with curative surgical resection for AMM were reviewed, 39 patients underwent APR, and 15 patients underwent LE. Life table was carried out and Kaplan-Meier test was used to compare the effects of these two different surgical procedures in survival. The overall 1-year, 2-year, 3-year, and 5-year survival rates after curative operation were 80, 54, 43, and 26%, respectively; LE group were 67, 48, 48, and 16%, and APR group were 84, 57, 42, and 30%, respectively. The median survival for all LE and APR were 25 months, 13 months, and 25 months, respectively. Kaplan-Meier test showed that there was no significant difference between APR and LE in survival (P=0.281); however, a 5-year survival advantage for the patients who underwent APR was found, despite the severity of tumor. Local recurrence after LE was more popular than APR (P=0.020). The prognosis of AMM after curative surgery is poor now, and patients undergoing APR have no significant survival advantage than those underwent LE. Local recurrence after LE was more popular than APR.

Treatment and outcomes of anorectal melanoma

INTRODUCTION

anorectal melanoma is an uncommon disease constituting less than 3% of all melanomas. Due to its rarity, there are a lack of randomized control trials regarding appropriate management and current evidence is based mainly on retrospective studies.

METHODS

in view of the controversial surgical treatment of anorectal melanoma, we review the most published literature in an attempt to elucidate its typical clinical features along with current thinking with respect to management approaches to this aggressive disease. Using the keywords "anorectal" and "malignant melanoma", a medline search of all articles in English was performed and the relevant articles procured. Additional references were retrieved by cross reference from key articles.

RESULTS

anorectal melanoma affects the elderly with a slight preponderance for females. It commonly presents disguised as benign disease with local bleeding or suspicion for haemorrhoidal disease. There is no convincing evidence to indicate that radical resection of primary anorectal melanoma is associated with improvement in local control or survival, and local excision is an acceptable treatment option.

CONCLUSION

optimum management depends on several factors and the therapeutic goals should be to lengthen survival and preserve quality-of-life. Given that wide local excision is a more limited intervention with comparable survival it should be considered as the initial treatment choice. Unfortunately prognosis for patients with this disease remains poor despite choice of treatment strategy with overall five year disease-free survival less than twenty percent in most studies.

Long-term outcomes after local excision and radical surgery for anal melanoma: data from a population database

PURPOSE

Anal melanoma is rare and associated with a poor outcome. Previous studies that have reported outcomes after surgical treatment are limited by both small number of participants and treatment at single centers only. This study evaluates survival of patients undergoing surgery for anal melanoma from a prospective, population-based database.

METHODS

Characteristics and survival of patients undergoing rectal resection or local excision for anal melanoma of the anus, anal canal, and overlapping region of the rectum from 1982 to 2002 were obtained from the Surveillance, Epidemiology and End Results database and compared.

RESULTS

A total of 160 patients were included in the study. Details of previous surgical procedures were available for 109 of the study patients: 60 (55%) underwent local excision and 49 (45%) rectal resection. Patients who underwent local excision were significantly older (73.5 vs 65.1 years, P < .001), whereas those who had undergone rectal resection had a greater proportion of regional disease (73.5% vs 16.7%, P < .001). The median survival of the 2 groups was similar (rectal resection vs local excision: 17 vs 28 months, P = .3). Rectal resection and local excision were associated with similar survival for patients in both regional (P = .6) and localized (P = .95) stages. Outcomes for patients who were appropriately pathologically staged after rectal resection depended on localized vs regional stage (5-year survival: 43.1% vs 12.5%, P = .17). Survival for patients in localized and regional stages who underwent rectal resection was similar to that for patients with corresponding clinical stage who underwent local excision.

CONCLUSION

Survival of patients with anal melanoma is similar after local excision or rectal resection irrespective of whether patients have localized or regional stage of disease.

Effect of misdiagnosis on the prognosis of anorectal malignant melanoma

OBJECTIVE

Anorectal malignant melanoma (AMM) is frequently subjected to misdiagnosis. Here the effect of misdiagnosis on the prognosis of AMM was investigated.

METHODS

Between 1995 and 2007, 79 patients managed for AMM were reviewed; 46 (58.23%) of them had been misdiagnosed during the symptoms, while 33 (41.77%) cases had been diagnosed exactly not more than 1 week after the first visit. Diseases misdiagnosed were categorized as cancer, hemorrhoids, polyps and other diseases. Data were statistically analyzed by using the life tables and Kaplan-Meier curves. The software used was SPSS 16.0 for Windows.

RESULTS

The 1-, 2-, 3- and 5-year survival rates of AMM patients were 58, 33, 24 and 16%, respectively, and the median survival time was 14.0 months; 1-, 2-, 3- and 5-year survival rates of the misdiagnosed patients were 61, 22, 22 and 11%, respectively, and the median survival time was 14.0 months; 1-, 2-, 3- and 5-year survival rates of the patients not misdiagnosed were 55, 44, 25 and 25%, respectively, and the median survival time was 12.0 months. Analyses based on Kaplan-Meier curves revealed no significant effect of misdiagnosis on the survival of AMM patients (P > 0.05). Nevertheless, the diseases misdiagnosed significantly affect the prognosis (P = 0.009); AMM misdiagnosed as hemorrhoids had a poor prognosis, with a 1-year survival rate of only 29% and the median survival of only 6.0 months.

CONCLUSIONS

The misdiagnosed patients had relatively poor prognosis, but the effect of misdiagnosis on the prognosis was not significant; however, misdiagnosis of AMM as hemorrhoids seriously affected the prognosis.

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.

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.

[Anal canal melanoma-- case report]

Anal canal melanoma is a rare disease comprising 1% of all colorectal ie. anal malignant tumours with very poor long term prognosis. Its significant biologic aggressivity is the consequence of the tendency towards lymphatic, local and hematogenous spread. At the moment of diagnosis even 30% of the patients have distant metastases. Surgical intervention represents the only possibility for cure. Modern approach to the anal canal melanoma treatment implies two types of intervention: wide local excision preserving the sphincter mechanism and abdominoperineal resection of the rectum. There are numerous dillemas about the choice of surgery in particular disease stages. The authors report on a 61 years old women in which anal canal melanoma with left inguinal lymphatic metastases was detected during the inspection of "haemorrhoids". After the diagnosis was established, abdominoperineal resection of the rectum was performed with dissection of both inguinal regions.

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.

[Primary anorectal melanoma]

OBJECTIVE

To specify the clinical and therapeutic aspects of anorectal melanoma.

METHODS

Nine cases of malignant anorectal melanoma were managed in the department of gastroenterology of the Ibn Rochd university hospital in Casablanca between 1984 and 2002.

RESULTS

There were 5 men and 4 women, with a mean age of 61 years. Clinical symptoms were dominated by rectal bleeding (7 cases) and rectal syndrome (5 cases). The tumor was blackish in 4 cases. Extension staging showed metastases in the liver in one patient and in the bones in another. One patient had undergone abdominoperineal resection, two transanal tumor resection, and in one patient radiotherapy was applied. Five patients refused any treatment. The outcome was marked by remission in 2 cases with an event free survival respectively of 10 and 21 months. Three patients died because of visceral metastases. Four patients were lost to follow-up.

DISCUSSION

The prognosis of anorectal melanoma is frightening because of late diagnosis and high malignancy potential. Treatment is based essentially on surgery.