Clinicopathological and immunohistochemical features of oral spindle cell carcinoma.

BACKGROUND: Oral spindle cell carcinoma (SpCC) is a rare variant of oral squamous cell carcinoma (SCC). The aims of this study were to compare the clinicopathologic and immunohistochemical features of oral SpCC with conventional oral SCC. METHODS: Five cases of oral SpCC and 10 cases of oral SCC (five well-differentiated and five poorly differentiated) were evaluated through conventional hematoxylin and eosin staining and immunohistochemical reactions to cytokeratins (CK), vimentin, desmin, smooth muscle actin, muscle-specific actin, S-100 protein, epithelial membrane antigen (EMA), p53, and ki-67. RESULTS: Oral SpCC showed predilection for males on their sixth decade of life, presenting clinically as painful infiltrative ulcers or ulcerated exophytic polypoid masses, preferably located on the alveolar mucosa. Mesenchymal markers were expressed in the spindle cell but not in the carcinomatous component of SpCC, and it was negative in all SCC. CKs AE1/AE3, 6, 14, and EMA were positive on both carcinomatous and spindle cell components of most SpCCs. These tumors also presented higher p53 and ki-67 expression and no CK 1 expression in contrast to well-differentiated SCC. CONCLUSION: Oral SpCC presented a different clinical profile than conventional SCC and histopathologic features and p53 and ki-67 expression closer to poorly differentiated SCC. Besides mesenchymal markers, CK AE1/AE3, 6, 14, and EMA expression on spindle cells may be useful as an adjunct on microscopical differential diagnosis of SpCC.

Peripheral dentinogenic ghost cell tumor: a case report and review of the literature.

Dentinogenic ghost cell tumor (DGCT) is a rare neoplasm, representing 1.9% to 2.1% of all odontogenic tumors. Few cases of DGCT have been reported and only 11 show no bone involvement. A rare case of peripheral DGCT is reported, located in the anterior mandible of a 45-year-old man. The patient presented a slow painless growth in the canine region of an edentulous mandible. Radiographically, no bone involvement was registered. The lesion was enucleated and microscopically characterized by islands of epithelial cells showing ameloblastomalike features in fibrous tissue. Dysplasic dentin and ghost cells were frequently observed. Areas showing a connection between tumor cells and the overlying mucosa were also identified. Immunohistochemical analysis demonstrated positivity for pan-cytokeratin, cytokeratin-14, and 2 neural markers. Denditric cells (Langerhans cells and melanocytes) were identified inside tumoral islands. A rare case of peripheral DGCT is reported, with immunohistochemical analysis and a review of the English literature.

Adenomatoid odontogenic tumor concomitant with cystic complex odontoma: case report.

This case report describes a 10-year-old female patient with an adenomatoid odontogenic tumor developing together with a cystic complex odontoma. This occurrence is considered very unusual. Immunohistochemical detection of cytokeratins AE1/AE3, CK5, CK8, CK10, CK14, CK19 and Ki-67 was performed.

Sebaceous carcinoma of the parotid gland in children: an immunohistochemical and ploidy study.

Sebaceous carcinoma (SC) is a rare malignancy, affecting mainly the periocular glands. To the best of the authors' knowledge, this is the first English-language report of parotid SC affecting children; two cases are presented. Immunohistochemical studies included 29 different antibodies (15 of these were cytokeratins, CKs). For each case, DNA ploidy status was determined using isolated nuclei stained with Feulgen and analysed using a DNA image cytometry system. Most of the tumour cells were positive for CKs AE1/AE3, 34B12, 5 and 7. The CK14 pattern depicted the monolayer of basal cells surrounding the islands of malignant tissue, while the more central sebaceous differentiated cells were negative. Epithelial membrane antigen was strongly positive in the well differentiated cells, while most of the basaloid peripheral cells were negative, and only a few cells were positive for carcinoembryonic antigen. beta catenin, E cadherin and C-erb B2 were expressed by most of the cells including the more differentiated sebaceous cells. Tumour cells were negative for muscle or myoepithelial markers, androgen, oestrogen and progesterone receptors. Both SCs were uniformly diploid, and showed low proliferative indices for p53, Ki-67 and Mcm-2, which is consistent with the good clinical course presented by these patients so far.