Analysis of prognostic factors and competing risks in 14, 805 cases with tonsil squamous cell carcinoma from the SEER database

Objective To evaluate factors associated with prognosis of tonsil squamous cell carcinoma (TSCC) patients and analyze the competing risks of death in TSCC patients.

Methods Data tonsil malignant tumors cases diagnosed between 1975 and 2020 were obtained from the SEER database, and records confirmed as squamous cell carcinoma were selected. A Cox proportional hazards regression model was used to investigate the relationships of gender, race, age, marital status, year of diagnosis, lesion location, pathological evidence, treatment regimen with overall survival rate as well as cause-specific mortality outcomes. The competing risks of cause-specific death outcomes among TSCC patients with different clinical characteristics were assessed.

Results This study included 14, 805 TSCC patients, including 11, 650 males, accounting for 78.69%. 93.99% of TSCC cases were diagnosed after the age of 45, with the highest incidence occurring in 45 to 64 age group. Radiotherapy was the most commonly used treatment modality (81.78%), compared to surgery (49.47%) and chemotherapy (47.10%). By the end of the follow-up period, 8, 003 (54.06%) TSCC patients had died, with a median survival time of 2.33 years. Cox proportional hazards regression analysis showed that the HR (95%CI) for TSCC-related deaths among patients not receiving surgery, radiotherapy and chemotherapy were 2.101 (1.972 to 2.239), 1.829 (1.702 to 1.966) and 1.023(0.951 to 1.100), respectively, compared to those who did receive these treatments; the HR (95%CI) for deaths due to other causes were 1.630 (1.513 to 1.756), 1.438 (1.318 to 1.570) and 1.328 (1.212 to 1.456), respectively. Compared to patients < 45 years old, the HR (95%CI) for TSCC-related deaths among patients ≥65 years old were 2.218 (1.933 to 2.545), and for deaths due to other causes were 6.178 (5.133 to 7.436).

Conclusion Radiotherapy, surgery and chemotherapy all contribute to improving the prognosis of TSCC patients. For elderly TSCC patients, particular attention should be paid to non-TSCC-related death risks.