We report an exceedingly rare case of amelanotic anorectal melanoma misdiagnosed as hemorrhoids. A 74-year-old man presented with a week's history of "blood on toilet tissue" without bowel complaints or history of cutaneous melanoma. Skin evaluation was normal. Rectal exam was negative for blood, but revealed an anal nodule, interpreted as a hemorrhoid. Hemoglobin was normal; bleeding persisted...

Hair follicles and sweat glands are recognized as reservoirs of melanocyte stem cells (MSCs). Unlike differentiated melanocytes, undifferentiated MSCs do not produce melanin. They serve as a source of differentiated melanocytes for the hair follicle and contribute to the interfollicular epidermis upon wounding, exposure to ultraviolet irradiation or in remission from vitiligo, where repigmentat...

Malignant melanoma (MM) of the vagina is a rare tumor. It accounts for less than 1% of all MM, and less than 3% of all primary malignant tumors of the vagina (1). In a review of reported cases, Stellato et al. (2) found less than 150 cases of primary melanoma of the vagina in the literature. The histologic appearance of melanoma may be heterogeneous. In fact, especially amelanotic melanomas may...

purpose: to report the clinical and histopathological features of recurrent atypical fibrous histiocytoma of the corneo-scleral limbus followed by intra-epithelial squamous neoplasia. case report: a 25-year-old female patient presented with a recurrent vascularized gelatinous mass in the left nasal limbus. the preliminary histopathological diagnosis of the previously excised lesion was an amela...