Pathology/Lab Coding Alert

Document site to choose the proper code.

You’ve read about ICD-10 coding for benign colon polyps in these pages before (Pathology/Lab Coding Alert Vol. 15, No. 11, “Answer ‘Where?’ for Adenomatous Colon Polyps”), but what about cancerous polyps? 

Here’s a brief primer for how to use ICD-10 to report polyps of malignant or uncertain behavior when you find them in your pathologist’s documentation. You’ll need this knowledge soon, because the ICD-10 implementation date is looming on Oct. 1.

Learn Malignant Polyp Crosswalks

If your pathologist diagnoses a colon polyp as adenocarcinoma, the following list shows the crosswalk you need to know from ICD-9 to ICD-10:

• 153.0 — Malignant neoplasm of hepatic flexure crosses to C18.3 — Malignant neoplasm of hepatic flexure
  

• 153.1 — Malignant neoplasm of transverse colon crosses to C18.4 — Malignant neoplasm of transverse colon
  

• 153.2 — Malignant neoplasm of descending colon crosses to C18.6 — Malignant neoplasm of descending colon
  

• 153.3 — Malignant neoplasm of sigmoid colon crosses to C18.7 — Malignant neoplasm of sigmoid colon
  

• 153.4 — Malignant neoplasm of cecum crosses to C18.0 —  Malignant neoplasm of cecum
  

• 153.5 — Malignant neoplasm of appendix vermiformis crosses to C18.1 — Malignant neoplasm of appendix
  

• 153.6 — Malignant neoplasm of ascending colon crosses to C18.2 — Malignant neoplasm of ascending colon
  

• 153.7 — Malignant neoplasm of splenic flexure crosses to C18.5 — Malignant neoplasm of splenic flexure
  

• 153.8 — Malignant neoplasm of other specified sites of large intestine No direct crosswalk exists, because the corresponding ICD-10 code has a different definition: C18.8 — Malignant neoplasm of overlapping sites of colon
  

• 153.9 — Malignant neoplasm of colon unspecified site crosses to C18.9 — Malignant neoplasm of colon, unspecified.
  

Carcinoma in situ is different: If the pathology report indicates carcinoma in situ, you have two code choices in ICD-9 and ICD-10, depending on location. Choose ICD-9 code 230.4 (Carcinoma in situ of rectosigmoid junction) or 230.3 (Carcinoma in situ of colon). Beginning Oct. 1, choose ICD-10 code D01.1 (Carcinoma in situ of rectosigmoid junction) or D01.0 (Carcinoma in situ of rectum).

Watch for ‘Uncertain Behavior’ Changes

If the pathology report indicates a polyp that is a neoplasm of uncertain behavior, you currently have a single code to report the condition: 235.2 (Neoplasm of uncertain behavior of stomach, intestines and rectum).

When you start using ICD-10, the location of the neoplasm will become important to your code selection. The codes have been separated under the subcategory D37.- with the fourth digit (1-4) specifying the exact location as follows:

• D37.1 — Neoplasm of uncertain behavior of stomach

• D37.2 — ... small intestine

• D37.3 — ... appendix

• D37.4 — ... colon.