Which marker is significant for diagnosing testicular cancer in males?

The marker significant for diagnosing testicular cancer in males is hCG, or human chorionic gonadotropin. This hormone is produced by the placenta during pregnancy, but in males, elevated levels can indicate the presence of germ cell tumors, including testicular cancer. Testicular tumors often secrete hCG, specifically non-seminomatous germ cell tumors, which can lead to an elevated hCG level detected in the blood.

Monitoring hCG levels is particularly useful not only for diagnosis but also for assessing treatment response and detecting recurrence after therapy. The other markers listed, such as insulin, Ca-125, and CEA, are associated with different types of cancers or conditions and do not have the same level of relevance for testicular cancer diagnostics. Insulin is more commonly related to diabetes and insulinomas, Ca-125 primarily pertains to ovarian cancer, and CEA is typically relevant in colorectal and some other cancers, but not specifically for testicular cancer. Thus, hCG is the most clinically significant marker in the context of diagnosing testicular cancer.