Follicular lymphoma grade IIIb, unspecified site

This code signifies a diagnosis of follicular lymphoma, specifically the aggressive grade IIIb subtype, where the primary anatomical location of the tumor is not documented or specified. Follicular lymphoma is a common indolent non-Hodgkin lymphoma, but grade IIIb exhibits more aggressive behavior, often requiring different treatment approaches.

Use this code when the physician's documentation clearly states follicular lymphoma, grade IIIb, but does not specify the affected lymph node region or extranodal site. This code is appropriate for initial diagnosis or subsequent encounters when the site remains unconfirmed or generalized.

• Always strive for greater specificity regarding the anatomical site if documented (e.g., C82.41 for lymph nodes of head, face, and neck).
• Do not use this code if the documentation indicates a different grade of follicular lymphoma (e.g., grade I, II, or IIIa).
• Ensure the medical record explicitly states "grade IIIb" to support the use of this specific code.