C40.20 Malignant neoplasm of long bones of unspecified lower limb

Billable ICD-10-CM code, FY2026. Acts as a Complication or Comorbidity (CC) as a secondary diagnosis.

Applies from C40 Malignant neoplasm of bone and articular cartilage of limbs

Use additional code

• code to identify major osseous defect, if applicable (M89.7-)

Risk adjustment (HCC)

• CMS-HCC V28: HCC 21 — Lymphoma and Other Cancers
• CMS-HCC V22: HCC 10 — Lymphoma and Other Cancers
• RxHCC V08: HCC 22 — Prostate, Breast, Bladder, and Other Cancers and Tumors
• ESRD V24: HCC 10

MS-DRG index

Defines the logic of DRG(s) 542-544 in MDC 08.

Approximate ICD-9-CM (GEMs)

• 170.7 Malignant neoplasm of long bones of lower limb (approximate)

Code annotations containing back-references to C40.20

Back-references to C40

• Type 1 Excludes: C41 Malignant neoplasm of bone and articular cartilage of other and unspecified sites ("malignant neoplasm of bones of limbs (C40.-)")
• Type 1 Excludes: C41 Malignant neoplasm of bone and articular cartilage of other and unspecified sites ("malignant neoplasm of cartilage of limbs (C40.-)")
• Type 1 Excludes: C49 Malignant neoplasm of other connective and soft tissue ("articular (C40-C41)")
• Code First: M89.7 Major osseous defect ("malignant neoplasm of bone (C40.-)")
• Code First: M90.6 Osteitis deformans in neoplastic diseases ("the neoplasm (C40.-, C41.-)")

Nearby codes

• C40.1 Malignant neoplasm of short bones of upper limb
• C40.10 Malignant neoplasm of short bones of unspecified upper limb
• C40.11 Malignant neoplasm of short bones of right upper limb
• C40.12 Malignant neoplasm of short bones of left upper limb
• C40.2 Malignant neoplasm of long bones of lower limb
• C40.20 Malignant neoplasm of long bones of unspecified lower limb (this code)
• C40.21 Malignant neoplasm of long bones of right lower limb
• C40.22 Malignant neoplasm of long bones of left lower limb
• C40.3 Malignant neoplasm of short bones of lower limb
• C40.30 Malignant neoplasm of short bones of unspecified lower limb
• C40.31 Malignant neoplasm of short bones of right lower limb