漫香阁

Question: What ICD-10-CM code should I use to prove medical necessity if our provider orders a CA 19-9 blood test with CPT^庐 code 86301?

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Answer: CPT^庐 code 86301 (Immunoassay for tumor antigen, quantitative; CA 19-9) describes a test that measures the amount of a protein called CA 19-9 (cancer antigen 19-9) in the blood. CA 19-9 is a type of tumor marker used primarily as a marker for pancreatic cancer. These markers 鈥渁re substances made by cancer cells or by normal cells in response to cancer in the body,鈥� according to Medline ().

Medicare indicates coverage of tumor markers is available for monitoring the response of certain malignancies to therapy and assessing whether residual tumor exists post-surgical therapy. Medicare goes on to state that the test is not indicated for diagnosing disease. Therefore, Medicare benefit coverage for medical necessity includes a number of ICD-10-CM codes, such as:

• C24.- (Malignant neoplasm of other and unspecified parts of biliary tract)
• C25.- (Malignant neoplasm of pancreas)
• C78.- (Secondary malignant neoplasm of respiratory and digestive organs)
• D37.- (Neoplasm of uncertain behavior of oral cavity and digestive organs)
• Z85.0- (Personal history of malignant neoplasm of digestive organs)

Private payers may, of course, have their own rules.

For more details about Medicare coverage limitations as stated in Publication 100-03, Section 190.30 and covered diagnoses to provide medical necessity for 86301, go to and locate the PDF document with the most current date.