Malignant neoplasms of breast (C50)

ICD-10 codes C50 and its subcategories are specifically used for classifying malignant neoplasms of the breast. These codes cover various locations within the breast, including the nipple and areola, central portion, quadrants, axillary tail, overlapping sites, and unspecified sites, with distinctions by side and gender where applicable.

The detailed range of C50 codes captures all primary malignant breast tumors, from the nipple and areola (such as C50.0 and its female and male subcodes) to specific quadrants like upper-inner (C50.2), lower-inner (C50.3), upper-outer (C50.4), and lower-outer breast quadrants (C50.5). Codes also exist for tumors of the axillary tail (C50.6) and overlapping breast sites (C50.8). The classification further differentiates malignancies by sex and exact location, aiding precise clinical documentation and billing. For example, C50.019 refers to malignant neoplasm of the nipple and areola in females and is associated with terms like "Primary Paget disease of nipple" and "Malignant neoplasm of nipple," helping coders connect common clinical terms to the right codes. Unspecified site codes such as C50.9 include synonyms like "infiltrating lobular carcinoma" and "HER2-positive carcinoma," reflecting diverse breast cancer subtypes. These codings are essential for identifying the cancer location and type, from initial diagnosis to treatment planning and outcomes tracking.