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

A national database analysis of the evolution of outcomes of surgery for anal melanoma

BACKGROUND

This study assessed trends in treatment and outcomes of anal melanomas over a 17-year period.

METHODS

NCDB was searched for patients with anal melanoma (2004-2020). Receiver-operating characteristic curve analysis was used to determine cutoff year marking increased overall survival (OS) of anal melanoma. Characteristics, treatments, and outcomes in consecutive time periods were compared.

RESULTS

A total of 815 patients (mean age: 67.2 years; 59.4% female) were included: 354 in Period 1 (2004-2012) and 461 in Period 2 (2013-2020). Period 2 included fewer abdominoperineal resections (18% vs. 28%, p = 0.002), more local tumor excisions (61.1% vs. 55%, p = 0.002), more often immunotherapy (odds ratio [OR]: 3.41, 95% confidence interval [CI]: 2.22-5.22, p < 0.001) and less often chemotherapy (OR: 0.516, 95% CI: 0.352-0.755, p < 0.001) administered and longer median OS (25.2 vs. 19.8 months, p = 0.006). Independent predictors of worse OS were older age (hazard ratio [HR]: 1.02, p = 0.012), higher Charlson score (HR: 2.32, p = 0.02), and greater number of positive lymph nodes (HR: 1.15, p < 0.001); conversely private insurance (HR: 0.385, p = 0.008) was predictive of increased OS.

CONCLUSIONS

Anal melanoma patients diagnosed between 2013 and 2020 underwent fewer abdominoperineal resections and more local excisions than patients diagnosed between 2004 and 2013. Increased immunotherapy and longer median OS were noted in period two. Age and private insurance were significant predictors of OS, remaining constant across time periods.

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.

Management of primary anorectal mucosal melanoma during the COVID-19 pandemic

Anorectal melanoma is a rare and difficult-to-diagnose highly malignant cancer with a poor prognosis. The treatment usually involves surgery and often includes adjuvants such as radiation therapy and immunotherapy. We present a case of a 77-year-old Peruvian who was eventually diagnosed with this cancer during the COVID-19 pandemic, which complicated her treatment and allowed the cancer to spread. Her treatment included abdominoperineal resection, bilateral pelvic lymphadenectomy, left internal iliac vein raffia and end colostomy, followed by 3D radiation therapy (50 Gy, 25 sessions) and systemic treatment with nivolumab, all of which were well tolerated. The patient was alive as of 20 August 2023, having survived for more than 3 years since the onset of symptoms.

Anorectal melanoma

Anorectal melanoma is an aggressive mucosal melanoma subtype with a poor prognosis. Although recent advancements have been seen for cutaneous melanoma, the optimal treatment paradigm for management of anorectal melanoma is evolving. In this review, we highlight differences in the pathogenesis of mucosal versus cutaneous melanoma, new concepts of staging for mucosal melanoma, updates to surgical management of anorectal melanoma, and current data for adjuvant radiation and systemic therapy in this unique patient population.

Long recurrence-free survival of localized rectal melanoma after abdominoperineal resection in comparison to partial excision and highlighting the place of immunotherapy: A case report

Rectal malignant melanomas (RMM) are remarkably uncommon, the rectal location represents less than one percent of all rectal cancer. Because of its low global survival rate, the surgical strategy is a subject of controversy for attaining a r0 resection. the palliative treatment is also debateable, but recently; radiotherapy and immunotherapy became the preferred treatment and offer the best outcome. to ensure r0 resection, abdominoperineal resection (apr) is considered the main surgical option, but because of its morbidity and functional limitations, local excision techniques such as endoscopic mucosal resection (emr) combined with chemoradiotherapy are being increasingly performed to preserve the quality of life and reduce local recurrence rate. In this report, we evaluate the place that apr still keeps as surgical procedure in comparison to partial excision. we report a case of a 72 years old patient, who presented rectal syndrome with rectorrhagia for 2 months, the diagnosis of localized rectal melanoma was confirmed by endoscopy, magnetic resonance imaging, histological analysis tissue with immunohistochemistry. the procedure strategy was a surgical treatment with apr. After a long recurrence-free survival period, the patient develops local recurrence and immunotherapy-resistant metastasis.

Treatment outcomes and prognostic factors in 47 patients with primary anorectal malignant melanoma in the immune therapy era

PURPOSE

Primary anorectal melanoma (ARM) accounts for approximately 1.2% of all melanomas and 16.5% of all mucosal melanomas. ARM is associated with the shortest interval to disease progression and the highest rate of metastasis; however, optimal therapeutic strategies for ARM remain controversial. This study aimed to assess the ideal surgical intervention for ARM and to determine the effect of immune checkpoint inhibitors (ICI).

METHODS

We included 47 patients with ARM treated at the National Cancer Center Hospital in Japan from 2011 to 2020. We performed a survival analysis for each of these groups: (i) patients with ARM (n = 47); (ii) operable non-stage IV cases at initial presentation (n = 35); and (iii) stage IV cases (n = 32).

RESULTS

The 5-year overall survival (OS) was 53.6%, and the median OS was 78.7 months in patients with ARM. No statistically significant difference in 5-year OS was found between rectal and anal sites (50.9% vs. 56.7%). In the non-stage IV subgroup, the type of surgery (abdominoperineal resection or wide local excision) did not correlate with OS (HR 1.85; 95% CI 0.46-7.5; p = 0.39). In the stage IV subgroup, the 2-year OS of the ICI treatment group was 61.4%, whereas that of the dacarbazine regimen group was 0% (p = 0.048).

CONCLUSION

Our ARM prognosis was better than that of previous studies. Our findings suggest that the availability of ICI therapy may improve survival in patients with advanced ARM. However, further research is warranted to identify both the clinical and molecular predictors of response to improve patient selection.

Extensive resection improves overall and disease-specific survival in localized anorectal melanoma: A SEER-based study

Background

Anorectal melanoma is a rare tumor with a dismal prognosis. The only promising treatment for anorectal melanoma is surgery, either extensive resection (ER) or local excision (LE). However, the optimal extent of resection is still controversial. The purpose of this study was to investigate whether the survival outcomes of anorectal melanoma at different stages are influenced by the surgical approaches (LE or ER) using the National Institute of Health's Surveillance, Epidemiology, and End Results Program (SEER) database.

Methods

The Surveillance, Epidemiology and End Results (SEER) database was queried to identify patients treated for anorectal melanoma (2000–2018). Overall survival (OS) and disease-specific survival (DSS) outcomes were compared for the two surgical approaches (ER or LE) stratified by stage (localized, regional and distant).

Results

A total of 736 patients were included in the study. Details of previous surgical procedures were available for 548 of the study patients: 360 (65.7%) underwent LE, and 188 (34.3%) underwent ER. In localized cases, 199 underwent LE, and 48 underwent ER. The OS (median 45 vs. 29 months, 5-year rate 41.7% vs. 23.4%) and DSS (median 66 vs. 34 months, 5-year rate 51% vs. 30.7%) of patients undergoing ER were significantly better (p = 0.009 and 0.041, respectively) than those who received LE. Multivariate analysis showed that the type of surgery was an independent prognostic factor for both OS and DSS. Among the regional cases, 89 cases had LE, and 96 cases had ER. Patients with regional disease who underwent ER had no significant differences in OS (23 vs. 21 months; p = 0.866) or DSS (24 vs. 24 months; p = 0. 907) compared to patients who underwent LE. In distant cases, 72 cases had LE, and 44 cases had ER. Patients with metastatic disease who had ER also had similar OS (median 11 vs. 8 months; p = 0.36) and DSS (median 11 vs. 8 months; p = 0.593) to those who underwent LE.

Conclusion

Extensive resection can improve the long-term prognosis of localized anorectal melanoma compared to local excision, but the prognosis of the two surgical techniques is comparable in both regional patients and distant patients.