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A 45‐year‐old male cook was seen for the evaluation and removal of a “mole on my eye” of steady growth during the previous 6 months. The patient stated that he had had a “brown spot” above his left eye for 17 years prior to its recent enlargement; it was now partly blocking the vision in his left eye. He denied a history or family history of cutaneous tumors, including skin cancer. On examination, a 2.5‐cm × 0.5‐cm × 0.8‐cm, horn‐like, darkly pigmented, cutaneous nodule was evident extending from the left upper eyelid downwards to below the lower eyelid (Figs 1 and 2). He also had scattered, skin‐colored, 2–3‐mm cystic papules on his anterior mid‐chest. A shave excision specimen was obtained from the eyelid nodule. 1 Horn‐like, cutaneous nodule extending from the left upper eyelid downwards to below the lower eyelid 2 Close up, demonstrating the morphologic features to better advantage Microscopic examination demonstrated acanthosis, hyperkeratosis, and papillomatosis (Fig. 3). Large dendritic cells with abundant melanin granules were spread throughout the epidermis. In addition, small basaloid or spinous keratinocytes were present in the malpighian layer. 3 Histology of the nodule, showing an epidermis with acanthosis, hyperkeratosis, papillomatosis, and large dendritic cells with abundant melanin granules spread throughout the epidermis (hematoxylin and eosin; original magnification, × 100)

Trichoepithelioma papulosum multiplex is an uncommon autosomal dominant disorder in which multiple trichoepitheliomas are seen. Its cause may be a defective tumor suppressor gene. Studies have mapped this gene to the 9p21 locus. However, there is a parallel or identical syndrome of multiple trichoepitheliomas and cylindromas. Within a given family, some members may have cyclindromas whereas others may have trichoepitheliomas or a combination of both. Although preliminary evidence suggests a different gene is responsible, it is possible that TPM may be caused by more than two independent genes, with some cases of TPM due to impairment of the gene for cylindromatosis. This entity, as well as other disorders with multiple appendageal tumors, may require clarification and distinction from TPM.

Trichoblastoma is an uncommon benign cutaneous neoplasm of the hair germ cell. The pigmented variety of the tumor is rare. There have only been a few case reports describing the malignant counterpart of trichoblastoma. There are no reports describing a pigmented variety of malignant trichoblastoma. We are presenting a case report of a 47-year-old patient with malignant trichoblastoma containing melanin deposits and propose to define this variety of the tumor as a separate entity: malignant melanocytic trichoblastoma.