Title: An Atypical Presentation of Diffuse, Multi-Focal Basaloid HPV-Related Squamous Cell Carcinoma of the Oral Cavity in the Setting of Prior Radiation
Author(s): Sidney Spencer, DO; Minahal Naveed, MD; Jaswanthi Dogiparthi, MD; Jared Bunevich, DO
Email: sspencer2@mercy.com
Introduction: Basaloid squamous cell carcinoma (BSCC) is an aggressive variant of squamous cell carcinoma often seen in the head and neck region, particularly the base of the tongue, hypopharynx and larynx, and less frequently in the mouth and oral mucosa [1,2]. First described in 1986 by Wain et al., BSCC is a high-grade and aggressive tumor with histopathological features of basal and squamous cell components, and increased propensity for metastasis especially to the lungs and liver [3,4,5]. The lesion has been previously described to be capable of recurrence, deep invasion, and lymph node involvement [1,4]. Although the etiology for BSCC and conventional oral squamous cell carcinoma (OSCC) are similar, such as history of smoking and alcohol exposure, recent studies have seen increased occurrence of BSCC with HPV found in the basaloid tumor, particularly of HPV genotype 16 seen in younger non-smoking patients [4]. Here we report a unique case of diffuse, multifocal HPV related BSCC in a 75 year old female with a previous history of radiation therapy for SCC of the epiglottis.
Case Report(s): Patient is a 75 year old female with prior history of chemotherapy and radiation for invasive, moderately-differentiated squamous cell carcinoma of the epiglottis (T2N2a) in 2012. Physical exam at that time demonstrated an elevated, erythematous rash-like mucosal lesion that extended from the oral vestibule and mucosa of the lower lip to the right buccal trigone area without significant induration. A 2 week trial of Decadron swish and spit did not resolve the lesions and a biopsy was taken from the lower lip mucosa in the office. Pathology returned as carcinoma with squamous features involving the minor salivary gland structures. Images of the lesion’s oral cavity are demonstrated below in Figure 1. Patient was taken to the operating room for further biopsies. Final pathology returned as HPV-related basaloid squamous cell carcinoma of biopsies from the right lower lip and right buccal mucosa. Additionally, the sections demonstrated variably sized nests of basaloid neoplastic epithelioid cells in the subepithelial soft tissue with some of the larger ones showing central, comedo-like necrosis and some smaller ones appeared to be present in the lymphatic channels. There was no direct connection between the tumor nests and the surface squamous epithelium and the surface squamous epithelium showed no evidence of dysplasia or carcinoma in situ. Patient was deemed a non-surgical candidate due to extensive/diffuse involvement and the debilitation that radical resection would cause. Recommendation after multidisciplinary tumor board was for systemic therapy and radiation. Follow up PET scan is currently pending.
Discussion: In conclusion, BSCC of the oral cavity is a rare and aggressive form of squamous cell carcinoma. Tobacco and alcohol use along with history of prior head and neck irradiation are all risk factors which our patient did exhibit [2]. This patient’s atypical presentation and multifocality both clinically and pathologically make this case unique and no similar cases were found upon literature review.
