Primary squamous cell carcinoma of the retromolar trigone (primary SCC RMT) is an uncommon malignant tumor. There is still much to learn about its clinicopathological characteristics and prognosis. In order to better understand the clinicopathological features and predictive survival aspects of primary SCC RMT, this study examined data from the SEER database from 2000 to 2020. Furthermore, in order to forecast the overall survival (OS) and cancer-specific survival (CSS) of patients with primary SCC RMT, we created nomograms.

The Surveillance, Epidemiology and End Results (SEER) database was used to retrieve the information on individuals with primary SCC RMT who received a diagnosis between 2000 and 2020. Both univariate and multivariate analyses were conducted using the Cox proportional risk regression model. Using R software, prognostic nomograms were created to forecast the OS and CSS likelihood. The nomograms' prediction abilities were evaluated using the consistency index (C-index), calibration curve, and receiver operating characteristic (ROC) curve.

A total of 1717 patients with primary SCC RMT were included, they were randomly assigned to the primary and validation cohorts in a 7:3 ratio using R software. Multivariate Cox regression revealed that age, marital status, regional nodes positive, Summary stage, TNM stage, T stage, N stage, surgery were independent prognostic factors of OS, and age, marital status, regional nodes positive, tumor sizes, Summary stage, N stage, surgery were independent prognostic factors of CSS in the primary cohort. The C-index of the nomogram OS was 0.705 (95 % CI: 0.685–0.725) and the C-index of CSS was 0.734 (95 % CI:0.714–0.754) in the primary cohort. In validation cohort, the C-index of the nomogram OS and CSS were 0.730 (95 % CI: 0.710–0.750) and 0.723 (95 % CI: 0.684–0.762), respectively. The 1-, 3-, and 5-year OS and CSS rates in the primary cohort and validation cohort were approximately in line with the nomogram estimations, in accordance to the calibration curves.

We conducted an analysis using the SEER database to investigate the features, survival outcomes, and prognostic parameters of patients with primary SCC RMT. And we developed two prognostic nomograms that can be used by clinicians to forecast the 1-, 3-, and 5-year overall survival and cancer-specific survival of patients with primary SCC RMT.