Oral Squamous Cell Carcinoma and Warthin Tumour Occurring As Synchronous Tumours: A Report of Two Cases.

Oral cancer is a common site of cancer worldwide with oral squamous cell carcinoma (OSCC) comprising the major segment. The risk factors include tobacco and alcohol abuse, betel quid, and areca nut consumption. Warthin tumour (WT), also known as papillary cystadenoma lymphomatosum is a benign tumour of the salivary gland. It is one of the most common benign parotid neoplasms with cigarette smoking and radiation exposure as possible cited etiologic factors. Rarely, two or more histologically distinct neoplasms may occur synchronously. The synchronous occurrence of OSCC and WT is infrequent. The aim of this case series is to report the incidence rate of synchronous OSCC and WT in our centre between 2010 and 2019 and their socio-demographic, clinical, histopathological features, management, and prognosis and discuss the relevant literature. Out of 143 OSCC cases reported in our centre from the year 2010 to 2019, two had synchronous OSCC and WT with an incidence rate of 1.4%. These two cases occurred in a 63-year-old female and a 68-year-old male both with smoking habits. One OSCC was present in the left buccal mucosa and the other in the right ventral surface of the tongue, whereas the WT in both cases occurred in the tail of the parotid. One patient had a recurrence and died while the other is under follow-up without any recurrence. These unusual findings of synchronous occurrence of WT at a distant site from the primary tumour may mimic a malignant disease, more likely a metastasis from the primary OSCC, which could further complicate the management of these patients. Therefore, radiologists, head and neck surgeons, and pathologists should be aware of the occurrence of these unusual presentations to avoid overtreatment in such cases.