Second Primary Spindle Cell Carcinoma of the Tongue: A Rare Histology

Spindle cell carcinoma (SpCC) is a rare variant of poorly differentiated squamous cell carcinoma (SCC), characterised by the presence of both squamous (carcinomatous) and spindle cell (sarcomatous) elements. Early detection and improvement in treatment for oral SCC lead to prolonged survival, thereby increasing the frequency of second primary tumours (SPTs) in the oral cavity. In this paper, we report a case of SpCC of the tongue in a 62-year-old male with a history of SCC; the right lateral border of his tongue status post-treatment completion four years ago, now presented with a polypoidal growth over the tip of his tongue for four months. An immunohistochemical study revealed features suggestive of SpCC (spindle cell pattern of cells, expression of vimentin, immunopositivity for cytokeratin (membranous), and focally positive for p40 (nuclear)). To the best of our knowledge, this is the first reported case of a spindle cell variant of SCC presenting as a second primary in an oral cancer survivor patient.