Upper lip invasion in primary buccal mucosa squamous cell carcinoma: A case report

Summary: Introduction: Squamous cell carcinoma (SCC) is the most prevalent form of cancer affecting the oral cavity. Most cases arise in the tongue, with other rare sources being the lip and buccal mucosa. Buccal mucosa SCC commonly spreads to adjacent oral subsites, including the Stensen duct, but less frequently involves the upper lip. This case presents a treatment refractory case of primary buccal mucosa squamous cell carcinoma with direct extension to the upper lip that resulted in a highly expanding tumor burden and ultimately, metastasis. Case Presentation: A 51-year-old-woman with a past dermatological history of hidrotic ectodermal dysplasia and psoriasis first noticed a small, 0.5 cm lesion in her right buccal mucosa, that within a three month period grew into her right oral commissure and upper lip. The lip lesion was small yet exophytic, firm and painful. A series of two biopsies were performed which confirmed the diagnosis of p53 positive squamous cell carcinoma of the buccal mucosa with direct extension to the upper lip. The lesion was initially treated with focal tumor resection and a two month course of radiotherapy until remission was reached. Following three years after remission, the squamous cell carcinoma reappeared in the upper lip, having already metastasized to adjacent lymph nodes and lung tissue. The patient was deemed a nonsurgical candidate and platinum-based chemoradiotherapy regimen was then pursued as management. The patient experienced severe chemotherapy induced dermatological complications including rashes, xerosis and psoriatic flares, after which therapy was halted. Over a course of three months without active chemoradiation, the lesion grew exponentially, becoming ulcerated, hypervascular and, ultimately, necrotic. Patient prognosis was deemed poor and palliative measures were pursued. Conclusion: Aggressive oral cavity squamous cell carcinoma prognosis is largely based on early tumor recognition, extensive surgical intervention and combined cancer therapy. In addition, immunotherapy with immune checkpoint inhibitors are viable options in the management of treatment-resistant SCC. Maralexa Martínez Valcárcel¹ 1. Ponce Health Sciences University, Ponce, Puerto Rico. UV Biology/Injury and Non-melanoma Cancers