Incidence rates and contemporary trends in primary urethral cancer.

PURPOSE

We assessed contemporary incidence rates and trends of primary urethral cancer.

METHODS

We identified urethral cancer patients within Surveillance, Epidemiology and End Results registry (SEER, 2004-2016). Age-standardized incidence rates per 1,000,000 (ASR) were calculated. Log linear regression analyses were used to compute average annual percent change (AAPC).

RESULTS

From 2004 to 2016, 1907 patients with urethral cancer were diagnosed (ASR 1.69; AAPC: -0.98%, p = 0.3). ASR rates were higher in males than in females (2.70 vs. 0.55), respectively and did not change over the time (both p = 0.3). Highest incidence rates were recorded in respectively ≥75 (0.77), 55-74 (0.71) and ≤54 (0.19) years of age categories, in that order. African Americans exhibited highest incidence rate (3.33) followed by Caucasians (1.72), other race groups (1.57) and Hispanics (1.57), in that order. A significant decrease occurred over time in Hispanics, but not in other race groups. In African Americans, male and female sex-stratified incidence rates were higher than in any other race group. Urothelial histological subtype exhibited highest incidence rate (0.92), followed by squamous cell carcinoma (0.41), adenocarcinoma (0.29) and other histologies (0.20). In stage stratified analyses, TNM stage exhibited highest incidence rate. However, it decreased over time (-3.00%, p = 0.02) in favor of TNM stage (+ 2.11%, p = 0.02).

CONCLUSION

Urethral cancer is rare. Its incidence rates are highest in males, elderly patients, African Americans and in urothelial histological subtype. Most urethral cancer cases are TNM, but over time, the incidence of TNM decreased in favor of TNM.