Follicular lymphoma grade IIIb, spleen

This code signifies a specific type of non-Hodgkin lymphoma, follicular lymphoma, which has progressed to a high-grade, aggressive form (grade IIIb) and is located in the spleen. Follicular lymphoma originates from B-lymphocytes and is characterized by a follicular growth pattern. Grade IIIb indicates a higher proliferation rate and a more aggressive clinical course compared to lower grades.

Use this code when documentation clearly states a diagnosis of follicular lymphoma, specifically identified as grade IIIb, with confirmed involvement of the spleen. This diagnosis is typically established through biopsy and histopathological examination of splenic tissue or imaging studies confirming splenic involvement in a patient with known follicular lymphoma.

• Ensure the pathology report explicitly states "follicular lymphoma grade IIIb" and "spleen involvement."
• Do not use this code for other grades of follicular lymphoma or if the primary site of involvement is not the spleen.
• Consider sequencing this code as the primary diagnosis when the lymphoma is the reason for the encounter, followed by any associated signs, symptoms, or complications.