Anaplastic large cell lymphoma, ALK-pos, nodes mult site

This diagnosis code identifies a specific type of non-Hodgkin lymphoma characterized by anaplastic large cells that test positive for anaplastic lymphoma kinase (ALK) protein. It indicates that the disease is present in multiple lymph node regions throughout the body, rather than a single site.

Apply this code when documentation confirms a pathological diagnosis of ALK-positive anaplastic large cell lymphoma affecting multiple lymph node groups. This typically follows biopsy and immunohistochemical staining or molecular testing for ALK rearrangement.

• Ensure the pathology report explicitly states "ALK-positive" and "anaplastic large cell lymphoma."
• Verify that the documentation specifies involvement of "multiple sites" within the lymph nodes.
• Distinguish from ALK-negative anaplastic large cell lymphoma or other types of non-Hodgkin lymphoma.