Metastatic leiomyosarcoma in the oral cavity: case report with protein expression profiles

Leiomyosarcoma (LMS) is a relatively uncommon malignant tumour derived from smooth muscle cells that rapidly metastasizes to distant regions. It rarely reaches oral tissues in which smooth muscle tissues are absent. We report the case of a 56-year-old woman who presented with LMS in the maxilla that had metastasized from a primary tumour in her uterus, received a total hysterectomy with bilateral salpingo-oophorectomy 9 months earlier. To reveal the poor prognosis of metastatic LMS, a total of 26 antibodies against different factors related to the proliferation, apoptosis, necrosis, and angiogenesis were simultaneously applied on the immunohistochemistry and immuno-blot detection in order to screen for expression n of different proteins in the metastatic LMS. Compared with the immunoreactions of primary uterine LMS, the different antibodies for cellular proliferation, i.e., proliferating cell nuclear antigen (PCNA), multiple primary neoplasm-2 (MPN-2), Max, p21, CDK4, p53, Rb-1, Bad, Bcl-2, epidermal growth factor receptor (EGF-R), hepatocyte growth factor (HGF), C-erbb2, Maspin, and DMBT-1, and those for angiogenesis, i.e., vWF, CD31, and Angiogenin, were more intensely expressed, while Bax, p16, Wnt-1, E-cadherin, and APC were relatively weakly expressed. In particular, beta-catenin was densely localized to the nuclei of tumour cells. These data suggest that rapid proliferation of the tumour cells is related to over-expression of different oncogenes, and that the infiltrative growth and early distant metastasis of these tumour cells are related to over-expression of angiogenesis factors. A total of seven cases of metastatic LMS to the oral cavity that had been published in the English literature were reviewed, and the reason for the poor prognosis in the metastatic LMS is suggested in this case report.