Question: The surgeon performed a cystoscopic bladder biopsy and noted in the operative report that the specimen was a stone-like structure with calcification attached to the right lateral wall of the bladder, measuring 3.6 mm. The pathology report confirmed the diagnosis of transitional cell carcinoma. What diagnosis and procedure codes should we use? AAPC Forum Participant Answer: When coding the diagnosis, it is important to assign the ICD-10-CM code based on the pathologist’s final diagnosis rather than relying solely on the surgeon’s description. This ensures coding to the highest degree of specificity. The correct diagnosis code for transitional cell carcinoma of the bladder, also called urothelial carcinoma, is C67- (Malignant neoplasm of bladder). To ensure accurate coding, it is important to provide a more specific code for the anatomic site of the malignancy mentioned in the surgeon’s preliminary report. Because the malignancy is located on the right lateral bladder wall, your final diagnosis will be C67.2 (Malignant neoplasm of lateral wall of bladder). You would also report 52204 (Cystourethroscopy, with biopsy(s)) for the bladder biopsy.