Increasing demand for orofacial tissue augmentation makes pathologists face new, and sometimes, puzzling granuloma types. Identification of the foreign product might be required for therapeutic or medico-legal reasons.

Lymphoepithelial carcinoma is a relatively common malignancy in the nasopharynx, but it rarely occurs in other sites. We report 3 additional cases of cutaneous location. Histopathologically, the tumors consisted of multiple well-circumscribed dermal-hypodermal nodules composed of aggregates of undifferentiated malignant cells. These cells had moderate amounts of eosinophilic cytoplasm and vesicular nuclei with prominent nucleoli. There was no squamous or glandular differentiation. For each case, a heavy lymphoplasmacytic infiltrate was found. No dysplasia was noted in the epidermis. In one case, the tumoral component showed numerous Sternberg-like cells scattered within a lymphocytic background. This case might be mistaken with a Hodgkin's lymphoma. Immunohistochemistry showed that the neoplastic cells were positive for cytokeratin and epithelial membrane antigen. In the present report, studying the stroma reaction cell components, we have stressed the presence of numerous factor XIIIa-positive dendritic cells in 2 cases. Because of the role of these cells in the immune response of normal stroma, their presence herein might be in relation with the favorable prognosis of this type of primary skin carcinoma. No Epstein-Barr viral genomic sequences were detected by in situ hybridization. This negativity for Epstein-Barr virus may be a help in the differential diagnosis from metastatic undifferentiated nasopharyngeal carcinoma.

Keratoacanthoma (KA) is a common keratinizing squamous cell neoplasm of unknown origin characterized by rapid growth and spontaneous involution. Trauma‐induced forms have been observed with various types of skin injury. To our knowledge, reports of KA arising at tattoo sites are scarce in the literature. A 41‐year‐old woman with no medical history presented for a rapidly growing nodule confined to the red part of a tattoo located on the scapula. Histology showed a keratin‐filled cuplike crater with an epithelial proliferation (hyperkeratosis, parakeratosis, no keratinocyte atypia). An inflammatory infiltrate in the dermis composed of lymphocytes and histiocytes intermixed with red ink‐related exogenous pigments was noted. Lack of papillomatosis and viral inclusions ruled out the diagnosis of viral wart, absence of granulomatous reaction ruled out deep fungal or mycobacterial infection and lack of cytological atypia and frank architectural abnormalities did not favour a squamous cell carcinoma. KA should be included in the list of cutaneous complications related to tattooing. Diagnosis can be challenging as differential diagnoses include pseudoepitheliomatous hyperplasia and squamous cell carcinoma. Removal of the entire area, thorough histological examination and careful follow up are mandatory.

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