Primary lymphomas of the genitourinary tract: A population-based study

Area of Science:

• Urology
• Oncology
• Epidemiology

Background:

• Primary extranodal lymphomas (PGUL) involving the genitourinary organs are uncommon malignancies.
• Understanding the incidence, trends, and outcomes of PGUL is crucial for patient management and research.

Purpose of the Study:

• To analyze population-based incidence rates and trends of primary extranodal lymphomas of the testis, kidney, bladder, and prostate (PGUL).
• To compare cancer-specific mortality (CSM) rates of PGUL with primary genitourinary cancers.

Main Methods:

• Population-based analysis using the Surveillance, Epidemiology, and End Results (SEER) database (1998-2015).
• Utilized Estimated Annual Proportion Change (EAPC) for trend analysis, multivariable logistic regression, and competing risks regression models.
• Compared CSM rates between PGUL and primary genitourinary cancers in surgically treated patients.

Main Results:

• PGUL incidence rates were 3.04% (testis), 0.22% (kidney), 0.18% (bladder), and 0.01% (prostate).
• Annual rates decreased significantly for renal-PL and prostate-PL.
• Testis-PL and renal-PL were independently associated with higher CSM rates compared to primary genitourinary tumors.

Conclusions:

• PGUL are rare, with declining incidence in kidney and prostate, but stable rates in testis and bladder.
• Testis-PL and renal-PL carry a worse prognosis regarding CSM compared to primary genitourinary cancers, even after adjusting for competing mortality.