ICD-10 Code C40.22 – Malignant neoplasm of long bones of left lower limb (2026): Diagnosis, Symptoms & Billing Guide
2026 ICD-10-CM Diagnosis Code C40.22 – Malignant neoplasm of long bones of left lower limb
What it is
This code identifies a malignant tumor arising in a long bone of the left lower limb, such as the femur, tibia, or fibula. Use it when the documentation specifies the left side and a long bone primary site.
Clinical signs
Clinical features vary; refer to documentation. Commonly recorded findings include localized bone pain, swelling, pathologic fracture, or imaging evidence of a destructive bone lesion.
When to use this code
Use C40.22 when the provider documents a primary malignant neoplasm in a long bone of the left leg. It also fits when pathology, imaging, or oncology notes clearly localize the cancer to the left femur, tibia, or fibula. Check documentation if the site is described only as bone or lower limb.
Do not use for
Do not use this code for malignant neoplasms of bone in the pelvis, foot, or unspecified lower limb. It is also wrong when the lesion is metastatic rather than a primary bone cancer.
Coding tip
Confirm both laterality and bone site in the record before assigning C40.22.