Pathology/Lab Coding Alert

Know primary and metastatic site or risk misdiagnosis

You can't assign the proper ICD-9 code for colon cancer if you don't know where it is. That's why you should look to the surgical and pathology reports to find where the surgeon removed the specimen and whether the cancer is primary or metastatic from another site.

Primary or Secondary Leads to Different Codes

Cancers originating in the large intestine are primary tumors, which means you-ll use a code from the -primary- column in the neoplasm table -- 153.x (Malignant neoplasm of colon) -- says Pamela Younes, MHS, HTL (ASCP), CPC, PA (ASCP), assistant professor at Baylor College of Medicine in Houston.

Exception: If the pathologist indicates that the specimen is a secondary malignancy, using terminology such as -metastatic from -,- you should instead choose the code from the -secondary- column in the neoplasm table -- 197.5 (Secondary malignant neoplasm of the large intestine and rectum).

Location Dictates Fourth Digit

Once you determine that you-re dealing with a primary colon cancer, you need to identify the specimen's location to choose the right code.

Fourth digit required: ICD-9 flags 153 with a -34th- symbol, meaning that you must select the fourth digit to assign the code to the highest specificity level. The specific codes for malignant colon cancer are:

- 153.0 -- Hepatic flexure

- 153.1 -- Transverse colon

- 153.2 -- Descending colon

- 153.3 -- Sigmoid colon

- 153.4 -- Cecum

- 153.5 -- Appendix

- 153.6 -- Ascending colon

- 153.7 -- Splenic flexure.

Don't truncate other or unspecified sites: What if the pathology report doesn't specify the location in the colon, or specifies some other site that isn't among those listed?

"Never truncate the code to 153 if you have an unknown or unlisted location,- Younes says. Instead, choose one of the following four-digit codes:

- 153.8 -- Other specified sites of large intestine

- 153.9 -- Colon, unspecified.

Large area: If the pathologist identifies colon cancer in contiguous or overlapping areas so that you cannot narrow the cancer origin to a single listed area, you should report 153.8.

Colon with rectum is different: If the pathologist diagnoses a primary malignant neoplasm involving the colon and rectum, you should report 154.0 (Malignant neoplasm of rectosigmoid junction) rather than any of the category 153 codes.