ICD-10 Code C40.2 – Malignant neoplasm of long bones of lower limb (2026): Diagnosis, Symptoms & Billing Guide
2026 ICD-10-CM Diagnosis Code C40.2 – Malignant neoplasm of long bones of lower limb
What it is
C40.2 identifies a malignant tumor arising in the long bones of the lower limb, such as the femur, tibia, or fibula. Use it when the record documents a primary bone cancer in one of these sites.
Clinical signs
Clinical features vary; refer to documentation. Commonly recorded findings include persistent localized pain, swelling, a palpable mass, or imaging evidence of a destructive bone lesion in a long bone of the lower extremity.
When to use this code
Use C40.2 when the provider documents a malignant neoplasm specifically involving a long bone of the lower limb and the site is not better specified elsewhere. It fits pathology, imaging, or operative notes that clearly identify the femur, tibia, or fibula. Check documentation if the lesion is metastatic or the exact bone site is unclear.
Do not use for
Do not use this code for benign bone tumors, non-neoplastic bone disease, or malignant tumors in the pelvis, upper limb, or short bones. If the cancer is secondary or the primary site is uncertain, check documentation.
Coding tip
Code only after confirming the malignant primary site and the specific lower-limb long bone in the medical record.