Nevus Lipomatosus Cutaneous Superficialis Associated with Trichofolliculoma: An Uncommon Duet of Rare Pathologies.

Nevus lipomatosus cutaneous superficialis (NLCS) and trichofolliculoma (TF) are both rare cutaneous hamartomatous lesions. However, the coexistence of NLCS and TF as a single lesion has been reported only in two other cases, that too in middle-aged individuals. We report the first case of NLCS associated with TF in pediatric age group and also, to the best of our knowledge, the first case reported from India.

Non psammomatous melanocytic schwannoma presenting as a subcutaneous nodule: A rare presentation of a rare lesion.

Melanocytic schwannoma (MS) is an extremely rare soft tissue tumor accounting for less than 1% of all primitive nerve sheath tumors, with a predilection for spinal nerve involvement. To date, only 20 cases of cutaneous/subcutaneous MS have been described in literature. Here, we describe a case of MS presenting as a subcutaneous nodule in a 22-year-old male in right thigh. On examination, the nodule measured 2.5 × 2.0 × 1.5 cm with overlying skin showing a bluish hue and an ulcer. With a preoperative diagnosis of hemangioma, the patient was taken up for wide local excision and was diagnosed as a case of non psammomatous melanocytic schwannoma based on clinical, histological, and immunohistochemical studies. Immunohistochemistry revealed positivity with S-100, HMB-45, and Melan A with pericellular Laminin positivity. Carney's syndrome was ruled out. MS needs to be differentiated from other pigmented lesions like pigmented neurofibroma, Bednar tumor, cellular blue neavus, and especially malignant melanoma, which has an obvious ominous prognosis. Since MS can show unpredictable behavior especially in absence of overt malignant features, a long term follow up with or without radiotherapy is recommended.

Low-grade malignant proliferating pilar tumor simulating a squamous-cell carcinoma in an elderly female: a case report and immunohistochemical study.

A 65-year-old lady presented with an ulcerated lesion over the occipital region of nine-year duration, an incisional biopsy of which was reported as squamous-cell carcinoma. A wide local excision was performed and the tissue was sent for histopathological examination which revealed a low-grade malignant pilar tumor. Focal invasion and atypia were noted. Immunohistochemical (IHC) analysis revealed positivity for CD34 and calretinin immunomarkers favoring outer root sheath origin. Ki67 immunostains revealed a relatively low immunoreactivity indicating the low-grade nature of the tumor; however, p53 immunostain showed strong diffuse nuclear staining confirming the malignant nature of the tumor. Proliferating pilartumors (PPT) are rare tumors and less than 100 well-documented cases of malignant PPT have been reported so far in the literature. These tumors have been recently classified into benign, low- and high-grade malignant tumors and statistically significant difference was found in their biological behavior. However, we propose that IHC can be of immense value in assisting the subtyping of the tumor, so that the behavior and role of adjuvant therapy can be validated in future studies.