Granular Cell Tumors are rare with only about 200 cases reported, some half of them in the mouth and neck. Whether it is cancer or not has been controversial but it has recenlty been shown to be of early neural origin(Rejas et al). However, some tumors behave benignly and others can be very agressive and the older literature contians many reports contrasting “malignant” and “benign” granulosa cell tumors. Only 2% pf granular cell tumors behave like cancers. NCI defines “cancer” as a term for diseases in which abnormal cells divide without control and can invade nearby tissues. Cancer cells can also spread to other parts of the body through the blood and lymph systems. Great majority of granular cell tumors do not have these charcteristics, and and they should not be considered to be cancer.
Rejas RA, Campos MS, Cortes AR, Pinto DD, de Sousa SC. The neural histogenetic origin of the oral granular cell tumor: an immunohistochemical evidence. Med Oral Patol Oral Cir Bucal. Jan 1 2011;16(1):e6-10.
Schrader, KA.; Nelson, TN.; De Luca, A.; Huntsman, DG.; McGillivray, BC. (Feb 2009). “Multiple granular cell tumors are an associated feature of LEOPARD syndrome caused by mutation in PTPN11.”. Clin Genet 75 (2): 185-9.
Habeeb AA, Salama S. Primitive nonneural granular cell tumor (so-called atypical polypoid granular cell tumor). Report of 2 cases with immunohistochemical and ultrastructural correlation. Am J Dermatopathol. Apr 2008;30(2):156-9.
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