Melanoma of anal canal

Melanomas are primarily tumours of the skin, but rarely occur at other sites like retina and anal canal. Anorectal melanoma is an uncommon condition associated with a very poor prognosis. The patient usually presents with per rectal bleed or mass. These are often misdiagnosed on presentation. Diagnosis is confirmed by biopsy. Treatment is abdominoperineal resection or wide local excision if tumour free margins can be obtained. We present a case of a 60 years old female who presented to the outpatient department with per rectal mass and bleed since 4 to 5 months and was diagnosed with melanoma anal canal on biopsy. CT scan abdomen and pelvis was done. Patient underwent abdominoperineal resection as wide local excision with sphincter saving was not possible due to the location and extent of tumour as seen on CT scan. Patient had an uneventful recovery after the procedure.

Melanoma anal, patología infrecuente, reporte de un caso / Anal melanoma uncommon pathology, case report / Melanoma anal, patologia infreqüente, relato de um caso

El melanoma anal (MA) es un tumor infrecuente, caracterizado por presentar un comportamiento agresivo y mal pronóstico(1). La sintomatología inespecífica con la cual se presenta y su similitud con etiologías benignas anorrectales, dificulta el diagnóstico y puede conducir a un retraso en el mismo(2)(3). Por lo tanto, es necesaria una exploración física minuciosa y un elevado índice de sospecha. Se discute el caso de una paciente que consultó por tumoración anal dolorosa, no pigmentada y rectorragia; a la que se le realiza diagnóstico de melanoma anal.

Anal melanoma (MA) is an infrequent tumor, characterized by aggressive behavior and poor prognosis(1). The nonspecific symptomatology and its similarity with benign anorectal etiologies, makes the diagnosis difficult and leads to a delay in it(2)(3).Therefore, a thorough physical examination and a high index of suspicion are necessary. The case of a patient who consulted for a non-pigmented and painful anal mass with rectal bleeding is discussed; which is diagnosed with anal melanoma.

O melanoma anal (MA) é um tumor infrequente, caracterizado por apresentar um comportamento agressivo e ter um mauprognóstico(1). A sintomatologia inespecífica da sua apresentação e a sua similaridade com etiologias benignas anorretais dificultam o diagnóstico e pode levar a um atraso do mesmo(2)(3). Por tanto é necessário uma exploração física minuciosa e um indice de suspeita elevado. Discute-se o um caso de uma paciente que consultou por uma tumoração anal, dolorosa, não pigmentada e retorragia, a qual se realizou o diagnostico de melanoma anal.