Osteitis deformans in neoplastic diseases, right forearm

This code signifies Paget's disease of bone (osteitis deformans) occurring in the right forearm, specifically when it is associated with a neoplastic process. This condition involves abnormal bone remodeling, leading to enlarged, misshapen, and weakened bones, with the added complexity of a co-occurring tumor.

Use this code when documentation clearly indicates a diagnosis of osteitis deformans affecting the right forearm, and there is an explicit link or association with a neoplastic disease. Supporting documentation should include diagnostic imaging (e.g., X-rays, bone scans) confirming Paget's disease in the specified anatomical site, along with pathology reports or physician notes detailing the neoplastic involvement.

• Always sequence the underlying neoplastic disease code first, followed by this code, to accurately reflect the etiology.
• Ensure the documentation specifies "right forearm" as the affected site; laterality and anatomical specificity are crucial.
• Distinguish from Paget's disease without neoplastic involvement (M88.-) or Paget's disease affecting other bone sites.