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Updated: Oct 25, 2025

A 3D Organotypic Melanoma Spheroid Skin Model
Published on: May 18, 2018
Anorectal Melanoma-Brownish Black Mass Not Always a Hemorrhoid
Jitendra Singh Nigam1, Nishit2, Tarun Kumar2
1Department of Pathology and Lab Medicine, All India Institute of Medical Science, Bibinagar, Telangana, India. nigamjs@gmail.com.
Abstract:
The non-specific clinical symptoms of anorectal brownish-black mass do not help to differentiate colorectal cancer, hemorrhoids, rectal ulcers which result in a delayed diagnosis or lead to inadequate management of lethal anorectal melanoma. Primary malignant melanoma of the anorectal region is an uncommon tumor, constituting approximately 1% of anal canal tumors which may be misdiagnosed clinically as hemorrhoids. Because of aggressive behavior and poor prognosis, efficient and prompt diagnosis is required in these cases. We report 2 cases of this rare tumor.
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