Basaloid Squamous Cell Carcinoma, an Aggressive and Rare Cancer of the Oral Cavity: Can We Prevent It at the Primary Care Setting?

Abstract

Oral cavity cancer represents about 2%-3% of all cancers worldwide, with more than 355,000 new cases per year, one-third of which are reported in developed countries. Oral cancer is also known to be extremely aggressive when detected late, thus presenting one of the lowest cancer survival rates. It is estimated that as much as 90% of oral cancers are attributable to tobacco and/or alcohol consumption and that high-risk human papillomaviruses (HPV) infections pose an independently increased risk for their development. Therefore, it can be a preventable disease when associated with changes in lifestyle and possible modifiable risk factors, combined with early and preventive intervention. Basaloid squamous cell carcinoma (BSCC) constitutes an aggressive and rare form of oral cancer, being one of the rarest and most aggressive variants of squamous cell carcinoma (SCC, the most common), and usually presents as a high-grade disease with a poor prognosis. It is typically associated with heavy smoking and alcohol abuse, occurring most commonly in older men. Here, we report a clinical case of a 60-year-old man with excessive consumption of both tobacco and alcohol, poor oral hygiene, and partial edentulousness who came to our primary health department with complaints of odynophagia twice in a four-year time-lapse. The first time, two whitish ulcerated lesions on the left tonsil were detected and biopsied but revealed a negative histological result. After four years, he came again to our primary health care department with similar complaints of odynophagia and also sore throat with radiation to the right ear, accompanied by globus sensation and anorexia. No suspicious lesions were detected, except a globally hyperemic oropharynx. Considering the history of abusive consumption, no improvement with symptomatic treatment, and persistent clinical signs, an extended diagnostic approach was carried out. After four months, a pharyngeal mass measuring 53 mm was detected on pharyngeal-neck computed tomography (CT), and the diagnosis of a BSCC located in the right tonsillar pillar and base of the tongue was finally determined. Unlike other cancers that have been detected earlier through screening programs, oral cancer is often detected at an advanced stage, compromising survival and quality of life. The opportunity to intervene early and preventively in consumption habits, promote healthy lifestyles, and try to prevent disease is unique at the primary care level. Moreover, opportunistic screening through a thorough examination of the oral cavity is extremely important for timely diagnosis and treatment.

Keywords: basaloid squamous cell carcinoma; oral cancer; oral cancer screening; prevention; primary care; risk factors.

Figure 1. Pharyngeal-neck and thorax computed tomography scans

(A) Coronal view of contrast-enhanced pharyngeal-neck computed tomography (CT) scan showing an expansive and infiltrative lesion on the right lateral wall of the oropharynx that extends from the plane of the soft palate to the base of the tongue and pharyngoepiglottic fold, reaching a maximum longitudinal axis of 53 mm (ruler). The lesion invades the root of the tongue and the sublingual space; (B) Coronal view of contrast-enhanced pharyngeal-neck CT revealing two coalescing adenopathies on the right involving levels II and III and reaching 55 mm (ruler) in the longest longitudinal axis - the uppermost solid and measuring 27 mm (ruler) and the lower, predominantly necrotic, measuring 29 mm (ruler) in the longest axis; and (C) Axial view of contrast-enhanced staging thorax CT revealing mediastinal involvement with heterogeneous adenopathies containing central areas of necrosis - the most expressive conglomerate surrounds the supra-aortic trunks, without a cleavage plane with the aortic arch, with a 73 mm longest axis (ruler) and causing a deviation of the trachea to the right