Diagnosis Assignment When Screening Colonoscopy Turns up a Polyp
When dealing with Medicare patients, if the physician discovers a polyp during what begins as a screening colonoscopy, you should retain the initial V code (for instance, V76.51 Special screening for malignant neoplasms; colon) as the primary diagnosis. “Whether or not an abnormality is found, if a service to a Medicare beneficiary starts out as a screening examination (colonoscopy or sigmoidoscopy), then the primary diagnosis should be indicated on the form CMS-1500 (or its electronic equivalent) using the ICD-9 code for the screening examination,” states MLN Matters article SE0746.
MLN Matters SE0746 further instructs that if the physician finds a neoplasm during a screening exam, you should “indicate the secondary diagnosis using the ICD-9-CM code for the abnormal finding (polyp, etc.).”
CMS guidelines as set forth in MLN Matters SE0746 mirror official ICD-9-CM guidelines, which state, “A screening code may be a first listed code if the reason for the visit is specifically the screening exam … Should a condition be discovered during the screening then the code for the condition may be assigned as an additional diagnosis” [emphasis added].
Although you should list the screening diagnosis first on your claim form, your diagnosis pointer should link the appropriate polyp diagnosis to the diagnostic colonoscopy CPT® code. Although somewhat confusing, CMS explicitly requires this coding.
In an example of a screening-turned-diagnostic colonoscopy, MLN Matters SE0746 instructs coders to enter a “2” in the diagnosis pointer (Item 24E on the CMS-1500 claim form), thus linking the CPT® procedure code to the “line 2” diagnosis (that is, the polyp). Further language in the article makes clear that the “2” in Item 24E is “to link the procedure (polypectomy or biopsy) with the abnormal findings (polyp, etc.).”
For example, during a previously scheduled screening colonoscopy for an average-risk Medicare patient, the physician discovers several polyps, which he removes immediately by snare technique. Because the service began as a screening, assign the screening V code (V76.51) as the first-listed diagnosis on line 21 (1) of the CMS-1500 claim form. Next, list an appropriate ICD-9 code to describe the neoplasm(s) the physician removed, such as 211.3, Benign neoplasm of other parts of digestive system; colon, on the line 21 (2). Link the polyp diagnosis to 45385 (listed in line 24.1.d), and place a “2” in box 24.1.E.
Some computerized billing systems do not allow a link from procedure code to a “secondary” diagnosis. In such a case, you may be tempted to report the polyp as the primary diagnosis, but this is contrary to Medicare requirements. If your billing system won’t allow you to follow CMS’ instructions regarding diagnosis coding for a screening colonoscopy turned diagnostic, contact your payer to ask for guidance.