Basal-Cell Carcinoma With Matrical Differentiation: Report of a New Case in a Renal-Transplant Recipient and Literature Review.

Basal-cell carcinoma with matrical differentiation (BCC-MD) is one of the rarest pathologic variants of basal-cell carcinoma, of which 41 cases have been so far reported in detail. One of them developed in a heart-transplant recipient. We report a new case of BCC-MD occurring in a renal-transplant recipient and review the relevant literature. A 75-year-old white man who had received a renal allograft 7 years ago developed a tumor on the left temple clinically suggestive of basal-cell carcinoma. Microscopically, the tumor associated features typical of basal-cell carcinoma (basaloid lobules with peripheral palisading and clefting) and pilomatricoma (presence of shadow/ghost cells). The 2 tumor components expressed variably beta-catenin, HEA/Ber-EP4, CD10, PHLDA-1, MIB-1/Ki67, calretinin, and bcl-2. BCC-MD has no distinctive clinical features. It affects predominantly male patients with a mean age of 69 years. More than half of cases appear on the head/neck area. Some cases harbor CTNNB1 mutations. Differential diagnosis includes tumors with matrical differentiation, namely pilomatrix carcinoma. The outcome is usually favorable after surgical excision, although regional lymph node metastases developed in 2 patients.

[Immunohistochemical evaluation of inflammatory reaction in a case of pilomatrixoma]. / Evaluarea prin imunohistochimie a reactiei inflamatorii intr-un caz de pilomatricom.

OBJECTIVES: To identify the types of the cells in a case of pilomatricoma and to evaluate the lesion's stage, the cells' proliferating rate and the associated inflammatory reaction. MATERIAL AND METHODS: The paraffin-embedded tissue was investigated by histological examination and by immunohistochemistry for the expression of some markers such as: cytokeratins, CD3, CD20, CD68, PCNA, CD34 II. RESULTS: The lesion presented the characteristic epithelial cells of a classical pilomatricoma: bazaloid cells, ghost cells and transitional cells. 10-15% of the bazaloid cells were PCNA+. The MNF 116 antibody labeled only some of the transitional and of the ghost cells. We found no CD3-positive cells and few CD20-positive cells. A marked inflammatory reaction was noticed, dominated by giant multinucleated cells, positive for CD68 and PCNA and a rich network of blood vessels with a high vascular density. CONCLUSION: The histological pilomatricoma diagnosis was straightforward on the basis of the bazaloid and ghost cells presence. Immunohistochemistry brought additional data regarding the cells proliferation rate, the stage of the lesion and the intensity of the associated inflammation.