Epidemiological, clinical, and prognostic analysis of oral squamous cell carcinoma diagnosed and treated in a single hospital in Galicia (Spain): a retrospective study with 5-year follow-up

Oral cancer is a common neoplasm worldwide, mostly corresponding to squamous cell carcinoma (OSCC). Unfortunately, its overall prognosis remains poor, with no improvement in recent decades. In this study, we have analysed the epidemiological, clinical, and prognostic characteristics of OSCC on patients of a specific Spanish region (Galicia), in order to improve its prognosis and apply effective preventive and early diagnosis measures. We retrospectively analysed 243 cases of OSCC, diagnosed and treated in a single hospital centre in Galicia between 2010 and 2015 (minimum of 5 years of evolution). Overall and specific survival were calculated (Kaplan-Meier) and associated variables were identified (log rank test and Cox regression). The mean age of the patients was 67 years, with the majority being male (69.5%), smokers (45.9%) and alcohol consumers (58.6%), who lived in non-urban areas (79.4%). Cases diagnosed at advanced stages entailed the 48.1% of the sample, and 38.7% of cases relapsed. The 5-year overall and disease-specific survival rates were 39.9% and 46.1%, respectively. Patients who consumed tobacco and alcohol had a worse prognosis. OSCC cases referred to hospital by specialist dentists had a better prognosis, as those who were previously diagnosed with an oral potentially malignant oral disorder (OPMD) or received dental care during OSCC treatment. In view of these findings, we conclude that OSCC in Galicia (Spain) still has a very poor overall prognosis, which is mainly related to the advanced age of the patients and the late diagnosis. Our study highlights the better survival of OSCC in relation to the referring health professional, the presence of a previous OPMD and the dental care after diagnosis. This demonstrates the importance of dentistry as a health profession involved in the early diagnosis and multidisciplinary management of this malignant neoplasm.