Follicular lymphoma grade IIIa, intra-abdominal lymph nodes

This code signifies a specific type of non-Hodgkin lymphoma, follicular lymphoma, which is characterized by a grade IIIa cellular differentiation. The disease is located within the lymph nodes found inside the abdominal cavity. This grade indicates a more aggressive form of follicular lymphoma compared to lower grades, but still generally less aggressive than diffuse large B-cell lymphoma.

Use this code when diagnostic pathology reports confirm follicular lymphoma, grade IIIa, and imaging or surgical findings specify involvement of intra-abdominal lymph nodes. This diagnosis is typically established via biopsy and immunohistochemical staining. Documentation must clearly indicate both the specific grade and the anatomical site of involvement.

• Ensure the pathology report explicitly states "grade IIIa" for follicular lymphoma; do not assume based on other findings.
• Verify the anatomical location is specifically "intra-abdominal lymph nodes" to differentiate from other nodal sites.
• This code requires a confirmed diagnosis; do not use for suspected or rule-out cases.