Radiology Coding Alert

Question: For ICD-10-CM code C50.1-, what constitutes the “central portion” of the breast? Is there guidance on how far outside the nipple or areolar region can still be considered the central portion of the breast?

Arkansas Subscriber

Answer: ICD-10-CM code C50.1- (Malignant neoplasm of central portion of breast) is reserved for reporting a malignant neoplasm located centrally in the patient’s breast. The patient may experience pain in the breast or nipple, breast size and shape changes, tenderness and thickening of the skin, and skin dimpling on the breast.

Code selection in the C50.1- category will depend on the patient’s gender and side of the patient’s body. You’ll choose from the following codes to report a malignant neoplasm located in the central portion of the patient’s breast:

• C50.111 (Malignant neoplasm of central portion of right female breast)
• C50.112 (Malignant neoplasm of central portion of left female breast)
• C50.119 (Malignant neoplasm of central portion of unspecified female breast)
• C50.121 (Malignant neoplasm of central portion of right male breast)
• C50.122 (Malignant neoplasm of central portion of left male breast)
• C50.129 (Malignant neoplasm of central portion of unspecified male breast)

The National Cancer Institute Surveillance, Epidemiology, and End Results Program (SEER) provides thorough guidance on site-specific coding. According to SEER’s Breast Solid Tumor Rules, the central portion of the patient’s breast comprises of “Area extending 1 cm around areolar complex” (https://seer. cancer.gov/tools/solidtumor/Breast_STM.pdf).

This means if you have a radiology report where the provider notes the tumor is located behind the nipple and the size of the tumor is 0.5 cm beyond the areola, then you’ll assign the appropriate C50.1- code.