The clinical features and optimal treatment of anorectal malignant melanoma

Abstract

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.

Perianal melanoma with a BRAF gene mutation in a young Portuguese Roma native

“…The main objective of surgery is to achieve a negative resection margin for local control, either through the use of intraoperative frozen sections or reoperative excision of margins 13. However, at a certain depth and size of tumour (>3 mm thick and >30 mm diameter), curative surgery cannot be achieved, in which case conservative local excision and adjuvant therapy can result in a better prognosis 11. Our patient´s primary tumour was 15 mm thick and 25 mm wide.…”

“…Neither has an advantage over the other in controlling locoregional recurrences 11. APR is recommended if the surgical margins are invaded, in the case of local recurrence or if the tumour is inaccessible 12.…”

“…APR is recommended if the surgical margins are invaded, in the case of local recurrence or if the tumour is inaccessible 12. Although recently, WLE with conservation of the anal sphincters has been preferred for a better quality of life after surgery 11. The main objective of surgery is to achieve a negative resection margin for local control, either through the use of intraoperative frozen sections or reoperative excision of margins 13.…”

“…The reported mean survival time for all patients with AMM has been reported as 15 months;23 others report 19–26.4 months 11. There was no reported age or survival difference between races; neither was there 5-year projected survival advantage identified for location (anal canal, rectum, anus) 23.…”

Chinese Guidelines on the Diagnosis and Treatment of Melanoma (2015 Edition)

“…The staging examinations include digital rectal examination, colonoscopy, endoscopic ultrasound, CT, MRI, and PET-CT, which can be used for assessing the tumor invasion depth, regional lymph node metastasis, and distant metastasis. Notably, MRI is a standard method for evaluating lesion area (195).…”