N63.42 Unspecified lump in left breast, subareolar

Billable ICD-10-CM code, FY2026.

Applies from N63 Unspecified lump in breast

Applicable to

• Nodule(s) NOS in breast

MS-DRG index

Defines the logic of DRG(s) 600-601 in MDC 09.

Approximate ICD-9-CM (GEMs)

• 611.72 Lump or mass in breast (approximate)

Code annotations containing back-references to N63.42

Back-references to N63

• Type 2 Excludes: R22.2 Localized swelling, mass and lump, trunk ("breast mass and lump (N63)")

Diagnosis Index entries for N63.42

• Lump › breast › subareolar › left

Nearby codes

• N63.3 Unspecified lump in axillary tail
• N63.31 Unspecified lump in axillary tail of the right breast
• N63.32 Unspecified lump in axillary tail of the left breast
• N63.4 Unspecified lump in breast, subareolar
• N63.41 Unspecified lump in right breast, subareolar
• N63.42 Unspecified lump in left breast, subareolar (this code)