C50.529

Billable

Malignant neoplasm of lower-outer quadrant of unspecified male breast

HCC Category Mapping

V28HCC 23 — Melanoma and Other Skin Cancers

0.251

V24HCC 12 — Breast, Prostate, and Other Cancers and Tumors

0.150

ESRDHCC 12 — Breast, Prostate, and Other Cancers and Tumors

0.000

RxHCCHCC 22 — Cancer, Other Specified Sites

0.000

What This Code Means

Cancer that starts in the lower outer area of a male breast when the specific breast side is not documented or unknown.

Coding Tips

•Use this code only when the laterality (left/right) cannot be determined; if known, use C50.521 or C50.522 instead
•The lower-outer quadrant is the most common location for breast cancer; ensure documentation specifies this location before coding

Clinical Significance

This unspecified laterality code for male breast cancer of the lower-outer quadrant should trigger a documentation improvement effort. Given the rarity of male breast cancer and the importance of precise cancer registry data, laterality should always be sought from imaging, pathology, or operative reports before accepting an unspecified designation.

Documentation Requirements

✓Confirmed male patient sex
✓Quadrant confirmed as lower-outer
✓Documentation of why laterality is unknown
✓Evidence of query attempt for laterality specification
✓Histological type and staging when available

Commonly Confused Codes

C50.521 — Right male breast, lower-outer quadrant; use when right is confirmed C50.522 — Left male breast, lower-outer quadrant; use when left is confirmed C50.929 — Unspecified site of unspecified male breast; even less specific — avoid when quadrant is documented

Code Hierarchy

└C50Malignant neoplasm of breast └C50.5Malignant neoplasm of lower-outer quadrant of breast └C50.52Malignant neoplasm of lower-outer quadrant of breast, male └C50.529Malignant neoplasm of lower-outer quadrant of unspecified male breast

└C50.529Malignant neoplasm of lower-outer quadrant of unspecified male breast