Question: We have a patient who had a radical prostatectomy for prostate cancer four years ago and now has reached the definition of biochemical failure. Our urologist is referring him to radiation oncology for further treatment. Is there a code for biochemical failure, or should I just report C61? Maryland Subscriber Answer: Before assigning any diagnosis, you should check the visit notes to verify whether the patient’s prostate specific antigen (PSA) has risen. If it has risen after treatment, assign R97.21 (Rising PSA following treatment for malignant neoplasm of prostate) as well as C61 (Malignant neoplasm of prostate) for the recurrence of the prostatic carcinoma.