Is CA (Cancer Antigen) 125 performed in males?

CA-125 Testing in Males

CA-125 testing can be performed in males, though it is not routinely recommended and has different reference values than in females. 1

Clinical Applications of CA-125 in Males

CA-125 is primarily known as an ovarian cancer marker, but it has several potential applications in male patients:

Diagnostic Uses

• Ascites evaluation: CA-125 can be elevated in males with ascites of any cause, though testing is not recommended as it may lead to unnecessary referrals 1
• Cardiovascular disease: Elevated levels have been observed in male patients with acute myocardial infarction and may have prognostic value 2
• Peritoneal malignancy: May be used in males with suspected peritoneal involvement from various cancers 3

Reference Values

• The reference value for CA-125 in healthy males is significantly lower than the standard cutoff used for females:
  • Male reference value: 20.17 U/mL (95th percentile) 4
  • Common findings: 78% of healthy males have values ≤10 U/mL, and 94% have values ≤15 U/mL 4
  • This contrasts with the traditional cutoff of 35 U/mL often used in clinical practice

Clinical Guidelines on CA-125 in Males

Current guidelines do not recommend routine CA-125 testing in males:

• The National Comprehensive Cancer Network (NCCN) guidelines for occult primary workup do not include CA-125 testing for males 1
• CA-125 testing is specifically recommended for females with suspected occult ovarian primary tumors presenting with mediastinal, inguinal, chest, peritoneal, or retroperitoneal malignancies 1
• For males with adenocarcinoma or carcinoma not otherwise specified, guidelines recommend PSA testing (for those >40 years) rather than CA-125 1

Important Considerations

False Positives

• CA-125 can be elevated in many benign conditions affecting males, including:
  • Peritonitis
  • Heart failure
  • Pleural effusion
  • Liver disease
  • Any condition causing serosal inflammation 5

Interpretation Challenges

• The extremely low index of individuality (≤0.6) for CA-125 in males suggests that reference change values (RCV) rather than absolute values should be used when monitoring patients 3
• Unidirectional RCV for CA-125 in males is approximately 34.3% 3

Warning

• Testing serum for CA-125 in patients with ascites is explicitly discouraged by the American Association for the Study of Liver Diseases, as it is very nonspecific and may lead to unnecessary gynecologic surgery referrals even in males 1

Conclusion

While CA-125 testing can be performed in males and may have some clinical applications in specific scenarios, it is not routinely recommended by clinical guidelines. When used, clinicians should be aware of the lower reference values in males and the high potential for false positives from numerous non-malignant conditions.