Unusual Papillary Squamous Cell Carcinoma of the Tip of Tongue Presenting in a Patient Status Post Heart Transplant.

Oral papillary squamous cell carcinoma (PSCC) is an unusual variant of squamous cell carcinoma with a better prognosis. The most common location of PSCC in the oral cavity is the gingiva and buccal mucosa, and it is exceedingly rare in the tongue. Herein, we present a case of PSCC in an 85-year-old male with a history of heart transplant and long-term use of immunosuppression medication. A verrucous pedunculated mass measuring 3.5 cm in the greatest dimension was present on the tip of tongue and a partial glossectomy was performed. Histological diagnosis was well differentiated PSCC with focal and minimal stalk invasion. No vascular nor perineural invasion was identified. Based on the current WHO and AJCC oral cancer staging system, the tumor stage was T2N0M0. The tumor cells were focally positive for p16, but in situ hybridization was negative for low-risk HPV (types 6 and 11) and high-risk HPV (types 16, 18, 31, 33 and 51). To the best of our knowledge, this is the first documented case of PSCC present on the tip of tongue in patients with long-term immune suppression. The pathogenesis, stage and prognosis of this entity are discussed. More case studies with long-term follow up are needed to achieve an accurate tumor stage and definite prognosis.