Rare case of primary rectal melanoma in situ - a case presentation

Webinr on Medical Events 2021

December 13, 2021 | Webinar

Emma Jane Hamilton

University of Queensland, Brisbane, Australia

Scientific Tracks Abstracts: J Health Med Informat

Abstract :

An 82 year old Caucasian female underwent colonoscopy for investigation of PR bleeding and iron deficiency anemia with faecal occult blood test 3 of 3 positive. She was found to have a large malignant appearing anorectal mass 1-2cm from the anal verge. Biopsies confirmed an ulcerated cellular malignant tumor with features suggestive of melanoma. The patient has no past history of any melanoma and this is believed to be a primary amelanotic melanoma of the rectum. MRI rectum demonstrated a 23mm diffuse thickening of the posterior wall of the rectum but no extension into mesolectal fascia, no extramural vascular invasion and no lymph node involvement. CT staging scans showed some scattered intrahepatic cysts but no definitive lesions concerning for metastasis. Her case was extensively discussed at the colorectal multidisciplinary team meeting to determine her best treatment modality. Given her age and comorbidities, including heart failure, recurrent unprovoked venous thromboembolism and previous breast cancer, the patient was deemed unsuitable for abdominoperineal resection (APR) or chemotherapy and given the MRI findings local resection was advised with adjuvant radiation treatment. The patient underwent local surgical resection by a colorectal surgeon on 15th November 2021 and has been recovering well. She will commence adjuvant radiotherapy in the coming weeks. Primary anorectal melanoma is a very rare condition with only a handful of cases in the published literature, often an aggressive disease with metastasis at time of diagnosis which complicates the surgical treatment of this condition.

Biography :

Dr Hamilton completed her Doctor of Medicine (MD) from University of Queensland in 2018. She has since worked for Queensland health as a doctor at Ipswich Hospital, where she is currently working as a general surgery principal house officer. Over the years she has held many leadership positions including Chair of Incision – UQ’s surgical interest group in 2018 and President of the junior doctor society Ipswich 2020. Her current interest is in pursuing general surgical training.