C50.319
BillableMalignant neoplasm of lower-inner quadrant of unspecified female breast
HCC Category Mapping
V28HCC 23 — Melanoma and Other Skin Cancers
0.251V24HCC 12 — Breast, Prostate, and Other Cancers and Tumors
0.150ESRDHCC 12 — Breast, Prostate, and Other Cancers and Tumors
0.000RxHCCHCC 22 — Cancer, Other Specified Sites
0.000What This Code Means
Cancer in the lower-inner area of a female breast when the specific side (right or left) is not documented.
Coding Tips
- •This is a less specific code; attempt to obtain clarification on laterality from the medical record or provider
- •Use only when bilateral status or unspecified laterality is explicitly documented
Clinical Significance
Malignant neoplasm of the lower-inner quadrant of unspecified female breast represents invasive breast cancer requiring staging, treatment planning, and ongoing surveillance. Breast cancer is risk-adjusted because it demands significant healthcare resources including surgery, radiation, chemotherapy, hormonal therapy, and long-term monitoring. The unspecified laterality indicates documentation does not identify the affected side, which should trigger a provider query.
Documentation Requirements
- ✓Pathologic confirmation of invasive malignancy (biopsy with histologic type — ductal, lobular, etc.)
- ✓Laterality must be queried if not documented — right or left breast
- ✓Gender documented as female to support gender-specific code selection
- ✓Quadrant or subsite location: lower-inner quadrant
- ✓Tumor size (T stage) and grade
- ✓Lymph node status (N stage) — axillary, sentinel node biopsy results
- ✓Estrogen receptor, progesterone receptor, and HER2 status
- ✓Stage grouping (I-IV)
- ✓Current treatment status (active treatment, hormonal therapy, surveillance)
Commonly Confused Codes
C50.311 — Right female; preferred when right documentedC50.312 — Left female; preferred when left documentedC50.329 — Same laterality but male breast; verify patient genderC50.211-C50.219 — Upper-inner quadrant; same medial orientation but upper position — verify upper vs. lowerC50.511-C50.519 — Lower-outer quadrant; same lower position but lateral vs. medial orientationC50.111-C50.119 — Central portion; adjacent to lower-inner but anatomically distinct
Code Hierarchy
└C50Malignant neoplasm of breast└C50.3Malignant neoplasm of lower-inner quadrant of breast└C50.31Malignant neoplasm of lower-inner quadrant of breast, female└C50.319Malignant neoplasm of lower-inner quadrant of unspecified female breast
└C50.319Malignant neoplasm of lower-inner quadrant of unspecified female breast