Prevalence and prognosis of synchronous distant metastatic tonsil squamous cell carcinomas

To analyze the prevalence proportions and prognostic factors of synchronous distant metastases in patients with tonsil squamous cell carcinomas (TSCC).

TSCC patients were extracted from the Surveillance, Epidemiology and End Results (SEER) database between 2010 and 2014. We examined the association between clinical manifestations and distant metastases using Chi-squared tests. Predictors of 5-year survival were assessed using univariate and multivariate analyses.

A total of 6193 patients were analyzed and lung was the most common site of distant metastases. Poorly/undifferentiated differentiation was found to be significantly correlated with lung metastasis (p=0.033) and liver and bone metastases were associated with African American (p=0.000 and p=0.000, respectively). A higher T classification was associated with higher prevalence of lung, liver, bone and brain metastasis (p=0.000, p=0.000, p=0.000 and p=0.007, respectively). The same results were found in N classification in lung, liver, and bone metastasis (p=0.000, p=0.000, and p=0.000, respectively). Worse prognosis was associated with older age, Blacks, lower grade, higher T and N classification, no surgery therapy and more metastatic sites.

Lung was the most frequent lesion of synchronous distant metastases and liver and bone metastases were associated with African American. Higher T and N classification were independent prognostic parameters for higher prevalence of lung, bone, liver and brain metastasis. Worse prognosis was associated with older age, African Americans, lower grade, higher T and N classification, no surgery therapy and more metastatic sites.