Follicular lymphoma grade IIIb, lymph nodes mult site

This code signifies a specific type of non-Hodgkin lymphoma, follicular lymphoma, which has progressed to a high-grade (grade IIIb) and involves multiple lymph node regions throughout the body. Follicular lymphoma is characterized by its distinct growth pattern of abnormal B-cells forming follicle-like structures. Grade IIIb indicates a more aggressive form with a higher proportion of large cells.

Apply this code when documentation clearly states a diagnosis of follicular lymphoma, specifically graded as IIIb, and indicates involvement of lymph nodes in more than one anatomical region (e.g., cervical, axillary, inguinal). This code is appropriate for both initial diagnosis and subsequent encounters where this specific stage and grade of lymphoma is being managed.

• Ensure the pathology report explicitly states "follicular lymphoma grade IIIb" and the clinical notes confirm multifocal lymph node involvement.
• Do not use this code for other grades of follicular lymphoma (e.g., grade I, II, IIIa) or for follicular lymphoma confined to a single lymph node region.
• Consider sequencing this code as the primary diagnosis when it is the reason for the encounter, followed by codes for any associated symptoms or complications.