Primary amelanotic melanoma of rectum is a very rare tumor accounting for less than 2% melanomas. It highly aggressive that often tends to invade lymph nodes or metastasize in the early course disease. The prognosis this bismal with five year survival 20%. We report case primary anorectum which preoperative biopsy was inconclusive, thus highlighting role immunohistochemical markers reach correc...

Malignant melanomas occasionally exhibit various divergent differentiation types. Of these, smooth muscle differentiation is extremely rare; only 1 case has been reported in the literature until recently. We report an extremely rare case of malignant melanoma with smooth muscle differentiation, which appeared as an amelanotic reddish nodule on the left toe.

Desmoplastic melanomas are rare amelanotic melanomas that usually occur on skin with sun exposure. In this report, we present a 72-year-old man who presented with a desmoplastic melanoma of the penis. To our knowledge this represents the first reported case of primary desmoplastic melanoma of the penis. We discuss the pathologic differential and histologic evaluation.

Subungual exostosis arises underneath the nail plate, originating from the underlying bone. The characteristic appearance of this disorder may occasionally mimic a wide variety of tumors, including subungual verrucae, endochondroma, fibroma, or amelanotic melanoma. With such a wide variety of similar-appearing tumors, optimal treatment of this disorder clearly lies in proper recognition and tre...

Apocrine hydrocystoma (AH) typically presents a translucent, skin-colored to bluish dome shaped cyst on the face, although it occurs in other sites [1]. It is not uncommon and occurs in adult life with no predilection for particular age group. Males and females are equally affected [2]. AH mimics basal cell carcinoma (BCC), blue nevus, amelanotic melanoma requiring histopathological confirmatio...

Previous quantitative estimates of blood flow of transplanted tumors have been lower than surrounding tissue. Using a modifi cation of the Fick principle with antipyrine-131!, tissue blood flow was estimated in the hamster amelanotic melanoma implanted in subcutaneous tissue over the femoral triangle. Mean tumor blood flow was higher than adjacent tissue, decreased with tumor age, and responded...