(0621) Clinical Outcomes and Prognostic Pathologic Features of Young Patients With Oral Cavity Squamous Cell Carcinoma

Introduction: Oral cavity SCC in young patients ( < 45 yrs) can be aggressive with elevated rates of recurrence and metastasis. "Worst pattern of invasion” (WPOI) has been described as a histologically based prognostic factor. We present potential risk factors and outcomes of SCC of the oral cavity with a focus on rates of WPOI in this population.

Methods: Retrospective cohort study at an academic tertiary care medical center involving patients treated between 2013-2023.

Results: There were 44 patients, with average age 36 (11-45); 24 male, 20 female. The majority of patients were never smokers (68%) or did not have a history of alcohol use (75%). Primary subsite was oral tongue (77%). Of the patients, 21 (48%) had no comorbidities. The average neutrophil to lymphocyte ratio was 18 (1.7-113). The most common primary tumor stage was T2 (32%) followed by T1 (23%), T3 (18%), and T4a (16%). The average depth of invasion was 9.5 mm (0.6-29). Perineural and lymphovascular invasion were detected in 22 patients (50%) and 12 patients (27%) respectively. Extracapsular extension was detected in 11 patients (25%). WPOI was recorded in 41 patients and 36 (88%) had aggressive grades of 4 (18) or 5 (18). The majority of tumors (92%) with aggressive WPOI were moderately or poorly differentiated. The average number of lymph nodes involved was 3 (0-34). Of patients with aggressive WPOI (36), 16 (44%) had more than 2 nodes involved. Treatments were surgery alone (39%), surgery then RT (27%), and surgery then CRT (30%). Of the total, 19 patients recurred, and 13 had aggressive WPOI. Of the latter, 9 were regional and/or distant. Overall survival rate in the cohort was 61% with the average time of survival in years being 4.68 (0.25-14) however this may not reflect the actual number as there were 5 patients who were lost to follow up.

Conclusions: A significant number of young patients with oral cavity SCC have high risk features such as high grade WPOI, and nodal involvement. This population also demonstrated high recurrence rate despite majority receiving adjuvant therapy. This highlights the need for early prevention, low threshold for intraop nodal evaluation, and frequent need for multimodality treatment in this population.