Malignant peripheral nerve sheath tumor in the maxilla: report of a rare case

Malignant peripheral nerve sheath tumor [MPNST] is a rare malignant tumor that develops either from a preexisting neurofibroma or de novo. The cell of origin is believed to be the Schwann cell and possibly other nerve sheath cells. In this report, we describe a rare case of MPNST that arise from the socket of second left maxillary molar that has been already extracted in a young man. He was referred to a dentist's office with a tumor-like mass of soft tissue on his left maxillary gingiva. Biopsy and histopathologic examination was performed and based on histologic and immuno-histochemical findings, the diagnosis of MPNST was made. MPNST is a rare malignant tumor in the oral cavity. Dentists must be careful and conscious because this rare malignancy can occur in gingiva and can mimic the clinical feature of any benign gingival enlargements

[Metastasis of clear cell renal carcinoma to the maxillary gingiva in a 75-year old man: a case report]

About 1% of all oral cancers are metastases of primary tumors elsewhere in the body and could be located in the soft tissue as well as in the jaw bones. Among all the primary tumors that arise below the level of the clavicle, renal cell carcinoma [RCC] is the third most common neoplasm according to metastasis in the head and neck region. Majority of the reported cases involve the jaw bones rather than the soft tissues. Here one case of metastatic RCC to the maxillary gingival is reported. The Patient was a 75 year-old man who chiefly complained about swelling in his anterior region of the maxillary gingival. Excisional Biopsy was performed. Metastatic clear cell Renal cell carcinoma [CCRCC] was diagnosed by microscopic examination by demonstrating islands of cells separated from each other by thin fibrovascular septa, with stroma containing numerous sinusoid like vessels and immunohistochemistry [IHC] Staining [S-100, vimentin, EMA,CEA, CD 10, CK7, TTF-1 and PSA]. CT scan confirmed tumor in the right kidney. Nephrectomy and chemotherapy were performed but patient died 9 months after treatment as a result of metastases to brain and lung. CCRCC arise from renal tubular epithelium. Microscopically differential diagnosis for jaw tumors with clear cells includes a broad spectrum of tumors such as odontogenic tumors, salivary gland tumors and metastatic tumors. Generally, an immunohistochemistry panel consisting of S-100, vimentin, EMA. CEA, CD10.CK7, TTF-1 and PSA is useful to diagnose CCRCC from other clear cell tumors. Although IHC aids us in diagnosis, other paraclinical procedures like imaging should be done, to confirm the diagnosis