Anorectal malignant 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.

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.

Spectrum of presentation in primary anorectal malignant melanoma and its management

The article presents a series of four patients with primary anorectal melanoma presenting to our institute between 2016 and 2021. The primary objective of the series is to give an overview of the variable presentation of this rare entity from a high-volume colorectal tertiary care centre in a developing country. The patients ranged in age from 55 to 73 years and were mostly women (except one). The clinical presentation varied from bleeding per rectum to tenesmus and mucus in stools, overlapping with those of inflammatory bowel disease and primary anorectal adenocarcinoma. All patients were treated with surgery (laparoscopic or open), ranging from local excision to abdominoperineal resection. All our patients had a good outcome after surgery with no mortality at 30 or 90 days after surgery. The article aims to present a comprehensive overview of the various options of management with evidence from the surgical literature.

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.

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.

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.

Sphincter-sparing local excision and hypofractionated radiation therapy for anorectal melanoma: a 20-year experience

BACKGROUND

Anorectal melanoma is a rare disease with a poor prognosis. Because survival is determined by distant failure, many centers have adopted sphincter-sparing excision for primary tumor control. However, this approach is associated with high rates of local failure (∼50%). In this study, the authors report their 20-year experience with sphincter-sparing excision combined with radiation therapy (RT) for the treatment of localized anorectal melanoma.

METHODS

The authors reviewed the records of 54 patients with localized anorectal melanoma who were treated at the University of Texas MD Anderson Cancer Center from 1989 to 2008. All patients underwent definitive local excision with or without sentinel lymph node biopsy or lymph node dissection. RT (25-36 grays in 5-6 fractions) was delivered to extended fields that targeted the primary site and draining pelvic/inguinal lymphatics in 39 patients and to limited fields that targeted only the primary site in 15 patients.

RESULTS

The 5-year rates of local control (LC), lymph node control (NC), and sphincter preservation were 82%, 88%, and 96%, respectively. However, because of the high rate of distant metastasis, the overall survival (OS) rate at 5 years was only 30%. Although there were no significant differences in LC, NC, or OS based on RT field extent, patients who received extended-field RT had higher rates of lymphedema than patients who received limited-field RT.

CONCLUSIONS

The current results indicated that combined sphincter-sparing local excision and RT is a well tolerated approach that provides effective LC for patients with anorectal melanoma. Inclusion of the inguinal lymph node basins in the RT fields did not improve outcomes and was associated with an increased risk of lymphedema.

Primary malignant melanoma of the vagina

OBJECTIVE

To describe the clinical and pathologic features of vaginal melanoma and to determine predictors of outcome in patients with this disease.

METHODS

Thirty-seven women with clinical and radiographic stage I vaginal melanoma treated at one institution between 1980 and 2009 were included in this retrospective study. Treatment modalities were assigned to one of three categories: pelvic exenteration, wide excision, and nonsurgical (primary radiation therapy, chemotherapy, or both). Overall survival and progression-free survival were calculated from the date of the surgical diagnosis.

RESULTS

The median age was 60.6 years. Eighty-four percent of patients were white. Vaginal bleeding was the most common presenting symptom. Lesions were located in the distal third of the vagina in the majority (65%) of patients. Initial management included a wide local or radical excision (76% of patients); pelvic exenteration (14%); and radiotherapy, chemotherapy, or radiotherapy and chemotherapy (10%). At a median follow-up of 17.4 months, 33 women experienced disease recurrence. Recurrence was local only in seven patients (22%), distant only in 20 (63%), and both in five (15%). The most common sites of distant recurrence were lungs and liver. Median progression-free survival was 11.4 months, and median overall survival was 19 months. The 5-year progression-free and overall survival rates were 9.5% and 20.0%, respectively. Patients treated surgically had significantly longer survival than those treated nonsurgically (P=.01). Radiotherapy after wide excision reduced local recurrence risk and increased survival from 16.1 months to 29.4 months, although the increase was not significant (P=.46).

CONCLUSION

Malignant vaginal melanoma, even when localized at presentation, has a very poor prognosis. Patients treated surgically have longer survival than those treated nonsurgically. Radiotherapy after wide excision reduces local but not distant recurrences.

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 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.

Factors Affecting Survival in Patients with Anal Melanoma

Anal melanoma is an aggressive tumor with a predilection for early infiltration and distant spread, resulting in poor overall survival. Because anal melanoma is rare, only small case series are reported in the literature, making it difficult to draw conclusions about optimal treatment and outcome. The Surveillance, Epidemiology, and End Results database was used to identify patients with anal melanomas from 1973 to 2001. In addition to demographics, disease extent at presentation, treatment administered, overall survival, and survival by decade of diagnosis were collected. A total of 126 patients with a mean age of 69.2 years was diagnosed with anal melanoma. Sixty-one per cent were female. Median follow-up was 22.5 months. Median survival was 10 months for those with distant disease, 13 months for patients with regional spread, and 34 months for patients with local disease (P = 0.0001). Five-year survival was 32 per cent, 17 per cent, and 0 per cent for patients presenting with local, regional, and distant disease, respectively (P = 0.0001). Neither age at diagnosis, operation performed, nor use of radiation significantly affected survival. Anal melanoma remains an uncommon but lethal disease. Extent of disease correlates with overall survival. Survival is improving, but the use and extent of operation are not associated with improved overall survival.

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.

Radiation therapy for malignant melanoma

Although surgery remains the primary treatment for patients with localized melanoma, available data indicate that there is a need for improved local-regional control in situations where complete surgical resection may be difficult or when high-risk features are noted pathologically. Retrospective and phase II prospective studies have revealed that elective/adjuvant radiotherapy can significantly improve the local-regional control rate in these clinical settings. The impact of elective/adjuvant radiotherapy on the incidence of distant metastasis and overall survival has yet to be determined, however. Additionally, there remains a role for radiotherapy as a primary treatment alternative for elderly patients with large facial lentigo maligna melanoma. The optimal radiation fractionation schedule remains controversial. The hypofractionated regimen is well tolerated, has resulted in improved local-regional control as compared with historical surgical results, and is convenient for a group of patients in whom survival expectations are low. Significant improvements in outcome will require commensurate improvements in systemic disease control. The importance of local control to reduce local morbidity, however, should not be underestimated, and future research goals should include randomized clinical trials to further define the role of adjuvant irradiation alone or in combination with systemic therapy.

Sphincter-sparing local excision and adjuvant radiation for anal-rectal melanoma

PURPOSE

To evaluate the outcome and toxicity of a sphincter-sparing treatment strategy in the management of patients with anal-rectal melanoma.

PATIENTS AND METHODS

Between 1989 and 2000, 23 patients with invasive anal-rectal melanoma were managed with sphincter-sparing surgical resection and adjuvant radiation. Surgery consisted of primary local excision, as well as dissection for patients with documented regional nodal disease. Adjuvant radiation was delivered using a hypofractionated regimen of 30 Gy in five fractions over 2.5 weeks. Adjuvant systemic therapy was delivered to nine patients: cytotoxic chemotherapy in seven and immunotherapy in two.

RESULTS

After a median follow-up of 32 months, 15 patients had relapsed and 15 patients had died. The actuarial 5-year overall, disease-specific, disease-free, and distant metastasis-free survival rates were 31%, 36%, 37%, and 35%, respectively. The actuarial 5-year local and regional nodal control rates were 74% and 84%, respectively. No patient had locoregional failure as the sole site of failure and no patient required salvage abdominoperineal resection (APR). By univariate analysis, patients with nodal disease at presentation had a decreased actuarial 5-year disease-specific (0% v 45%, P =.004), disease-free (0% v 45%, P <.001), and distant metastasis-free survival (0% v 42%, P <.001). The actuarial complication-free survival rate was 71%. Two patients developed mild scrotal edema (grade 1), and four patients developed moderate proctitis requiring prolonged medical management (grade 2).

CONCLUSION

Sphincter-sparing local excision and adjuvant radiation is well tolerated and can effectively control local-regional disease while avoiding the functional morbidity of APR.

Successful palliation of stenosing anorectal melanoma by intratumoral injections with natural interferon-beta

Anorectal malignant melanoma is an uncommon tumour. Unlike for cutaneous melanoma, there are few guidelines for its optimal management. In particular, very few palliative treatment strategies have been described for patients with advanced disease. We report on an 80 year old patient with locally advanced anorectal melanoma nearly completely blocking the anal orifice and disseminated metastases. Complete regression of the primary tumour and partial remission of the metastases was achieved with intratumoral injections of natural interferon-beta and systemic administration of dacarbazine. The quality of life in this patient was improved markedly by providing relief from severe rectal pain and bleeding. We propose that conservative treatment strategies such as intratumoral injections with interferon-beta should be considered as a palliative treatment option for stenosing anorectal melanoma before an abdominoperineal resection is recommended.