Primary mucosal melanomas arise from melanocytes located in mucosal membranes lining respiratory, gastrointestinal and urogenital tract Although a majority of mucosal melanomas originate from the mucosa of the nasal cavity and accessory sinuses, oral cavity, anorectum, vulva and vagina, they can arise in almost any part of mucosal membranes Most of mucosal melanomas occur in occult sites, which together with the lack of early and specific signs contribute to late diagnosis, and poor prognosis Because of their rareness the knowledge about their pathogenesis and risk factors is insufficient, and also there are not well established protocols for staging and treatment of mucosal melanomas Surgery is the mainstay of treatment, with trends toward more conservative treatment since radical surgery did not show an advantage for survival Radiotherapy can provide better local control in some locations, but did not show improvement in survival There is no effective systemic therapy for these aggressive tumors Compared with cutaneous and ocular melanoma, mucosal melanomas have lowest percent of five-year survival Recently revealed molecular changes underlying mucosal melanomas offer new hope for development of more effective systemic therapy for mucosal melanomas Herein we presented a comprehensive review of various locations of primary melanoma along mucosal membranes, their epidemiological and clinical features, and treatment options We also gave a short comparison of some characteristics of cutaneous and mucosal melanomas

Primary mucosal melanomas: a comprehensive review.

Mucosal melanomas are aggressive cancers of mucosal surfaces with clinical and pathologic characteristics distinct from cutaneous melanomas, warranting different staging systems and treatment approaches. Surgical resection is performed frequently for the primary tumor, although the utility of lymph node surgery and radiation therapy is not established. Therapies targeted against C-KIT activating mutations, identified in many mucosal melanomas, are emerging as promising treatments.

Update on primary mucosal melanoma.

The first case of anorectal malignant melanoma (ARMM) was reported by Moore in 1857. Anorectal malignant melanoma is an extremely rare malignancy and represents only 0.05% of all malignant colorectal neoplasms and 0.5% to 4.6% of all malignant anorectal cancers that have been described. Up to 67% of patients are found to have distant metastases at the time of initial presentation, which is associated with extremely poor prognosis and median overall survival between 8.0 and 18.6 months. A large series analyzing 85,000 patients with melanoma showed that mucocutaneous melanoma was found in 1.3% only and 24% of these were ARMMs. Highly experienced cancer centers generally treat no

https://www.journalacs.org/article/S1072-7515(13)00229-9/pdf

Anorectal Malignant Melanoma: Extensive 45-Year Review and Proposal for a Novel Staging Classification

The aim of the present study was to evaluate by immunohistochemistry the prognostic meaning of the tumor marker MET (hepatocyte growth factor) in patients submitted to surgical resection due to primary colorectal adenocarcinoma. Patients and Methods: A retrospective study was carried out that included 286 consecutive patients with colorectal adeno- carcinoma, submitted to surgical resection at Barretos Cancer Hospital, from 1993 to 2002. The histopathological expression of the MET tumor marker was evaluated using an anti-protein monoclonal antibody against MET by the streptavidin-biotin- peroxidase technique. The expression of the tumor marker was semi-quantitative, and the slide samples were independently analyzed by three pathologists unaware of patient clinical and histopathological data. Results: The tumor marker expression was positive in 236 (79%) out of a total of 286 patients. This expression was statistically significantly different between stages I and IV (p=0.004), for overall survival (p=0.009), and for cancer-related mortality rates (p=0.022). However, no association between the tumor marker and recurrence (p=0.89) or disease-free interval (p=0.91) was observed. Conclusion: MET has shown significant expression at advanced stages of the disease, as well as for overall survival and cancer-related mortality rates demonstrating to be a valuable marker for poor prognosis in colorectal cancer patients.

https://repositorium.sdum.uminho.pt/bitstream/1822/30089/1/oliveira%20att_%20anticancer%20res%202009.pdf

MET Is Highly Expressed in Advanced Stages of Colorectal Cancer and Indicates Worse Prognosis and Mortality

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 be

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

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.

Anorectal malignant melanomas: retrospective experience with surgical management.

AIM: To evaluate the prognostic factors for 5-year survival after local excision of rectal cancer, and to examine the therapeutic efficacy and surgical indications for this procedure.

METHODS: Clinical data, obtained from 106 local rectal cancer excisions performed between January 1980 and December 2005, were retrospectively analyzed. Survival analysis was performed using the Kaplan-Meier method, statistical comparisons were performed using the log-rank test, and multivariate analysis was performed using the Cox proportional hazards model.

RESULTS: Transanal, transsacral, and transvaginal excisions were performed in 92, 12, and 2 cases, respectively. The rate of complication, local recurrence, and 5-year survival was 6.6%, 17.0%, and 86.7%, respectively. Univariate analysis showed that T stage, vascular invasion, and local recurrence were related to the prognosis of the cases (P < 0.05). Multivariate analysis showed that T stage [P = 0.011, 95% confidence interval (CI) = 1.194-3.878] and local recurrence (P = 0.022, 95% CI = 1.194-10.160) were the major prognostic factors for 5-year survival of cases after local excision of rectal cancer.

CONCLUSION: Local rectal cancer excision is associated with few complications, and suitable for stages Tis and T1 rectal cancer. Prevention of local recurrence, active postoperative follow-up, and administration of salvage therapy are the effective methods to increase the efficacy of local excision of rectal cancer.

Yong-Kai Wu

Papers

Anorectal malignant melanomas: retrospective experience with surgical management.

Prognostic factors for 5-year survival after local excision of rectal cancer.