P-0295 Anorectal Melanomas In Department of Medical Oncology, Hassan II University Hospital, Morocco

Abstract

ABSTRACT Introduction Melanomas are malignant tumors developed from the pigment system. The anorectal location is characterized by its rarity (1-3% of all melanomas) and its bad prognosis. The aim of this work is to show the rarity of this localization, treatment options and prognostic factors. Methods We report 6 cases of anorectal melanomas treated in department of medical oncology at Hassan II University hospital, between January 2007 and January 2012. Results Six cases of anorectal melanomas were collected. The mean age was 64 years (50-81ans), 4 men and 2 women. The symptomatology was mainly proctalgia, rectal syndrome, rectal bleeding and transit disorders. Colonoscopy was performed in all cases and revealed a circumferential non-pigmented burgeoning tumor in all cases and stenotic tumor in 5 cases. The radiological assessment included a thoraco-abdomino-pelvic scan in all cases and 2 patients underwent a pelvic MRI. Five patients had a metastatic disease, all in the liver, lymph node and lung. Only one patient was not metastatic and proceeded to surgery, he underwent an abdomino-perineal resection with lymphadenectomy; but his evolution was marked by occurrence of pulmonary and hepatic metastases 6 months later. First-line chemotherapy was received in all patients; it included paclitaxel-carboplatin in 2 cases, dacarbazine in 2 cases. Two patients; with over expression of C-Kit; received Imatinib with good clinical and radiological response. Three patients died with a median survival of 11 months from diagnosis to the date of death. Conclusion The prognosis of anorectal melanomas remains very bad because of late diagnosis and high metastatic potential. Treatment must be early and multidisciplinary. The new targeted therapies are hopeful.