Primitive Ano-rectal area melanoma:Case Report M.ANAJJAR . 𝟏 ,S.BENAMMI . 𝟐 , M-S. BELHAMIDI . 𝟏 ,M.BOUZROUD . 𝟏 , M.ESSARGHINI . 𝟏 , B.AITIDIR . 𝟏 , M. TARCHOULI . 𝟏 , S-M. BOUCHENTOUF . 𝟏 , A. AIT AL . 𝟏 I, A. BOUNAIM . 𝟏 Department of Visceral Surgery I, Military Hospital Mohammed V- Rabat 𝟏, Pediatric Anesthesiology-Reanimation, Pediatric Hospital . 𝟐 CONGRES NATIONAL DE CHIRURGIE MARRAKECH 2017

CONGRES NATIONAL DE CHIRURGIE MARRAKECH 2017 Introduction Ano-rectal melanoma is a rare tumor representing around 1.5% of all melanomas tumor. And it is characterized by its rapid extension, therapeutic difficulties, absence of specific symptoms and severe prognosis. We report four cases of anorectal melanoma showing its rapid extension and therapeutic difficulties. CONGRES NATIONAL DE CHIRURGIE MARRAKECH 2017

CONGRES NATIONAL DE CHIRURGIE MARRAKECH 2017 Material and Methods We report the case of three women of 32, 38 and 48 years of age and a 40-year-old man, whom symptomatology was dominated by minimal rectal bleeding and transit disorders. The clinical examination showed a burgeoning tumor at the anal margin in all four patients, and the proctologic examination biopsy confirmed the diagnosis of melanoma. No skin lesion was reported neither found in four patiente, therefore the primitive origin is retained which was confronted with the extension . The fourth patient had visceral metastasis in the pretherapeutic work-up and did not underwent surgical resection. The three others patients had an abdominoperineal resection. Three patients died within a few months from metastatic extension causing a cachexia state . The fourth patient has no local recurrence, however a non-resecable liver metastases was diagnosed after a five-month follow-up.   Figure 1. Anatomic features of the anal canal CONGRES NATIONAL DE CHIRURGIE MARRAKECH 2017

CONGRES NATIONAL DE CHIRURGIE MARRAKECH 2017 Results Primary anorectal melanoma is a rare tumor representing 0.1 to 0.5% of anorectal cancers and 1.5% of all melanomas. They occur as third most common site after the cutaneous and retinal sites. The average age of onset is around 50 years with an equal frequency of both sexes. The symptomatology is not specific. The most common signs are rectal bleeding, rectal syndrome and transit disorders. Proctologic examination reveal in most cases bourgeonate tumors. And histology shows proliferations of fusiform cells or round cells. The diagnosis is confirmed by the detection of melanin pigments. And the appreciation of the locoregional extension was revolutionized by the echo-endoscopy, which makes it possible to evaluate the parietal invasion as well as the per-rectal ganglionic involvement. And finally CT and pelvic MRI make it possible to specify the extent of the tumor, specialy haematogenous spread which is extremely frequent and often precocious. 20-30% of patients have metastasis at diagnosis. And the liver and lungs are the most affected. Surgery is the treatment of choice, but its methods of excision, neither local or abdomino-perineal amputation, remain controversial. Radiotherapy is used as a palliative therapy for tumors considered to be inextricable, in the case of recurrences or for an analgesic purpose. Chemotherapy and immunotherapy have not proved effective. proliferation of round, oval cells with a large nucleolus and a cytoplasm with melanin pigment (HES, G.400) Pelvic MRI Tumor of the anal canal invading the sphincter system CONGRES NATIONAL DE CHIRURGIE MARRAKECH 2017

Conclusions The prognosis of anorectal melanomas remains compromised  due to diagnostic delay, high malignant potential and therapeutic difficulties. And surgery is still the treatment of choice References Figure 1. Anatomic features of the anal canal : Inflammatory and Neoplastic Disorders of the Anal Canal Thomas P. Plesec Scott R. Owens CONGRES NATIONAL DE CHIRURGIE MARRAKECH 2017 CONGRES NATIONAL DE CHIRURGIE