Guidelines for staging and measuring response in non-Hodgkin lymphoma

This study provided updated guidelines and recommendations for the staging, response assessment, and follow-up of patients with non-Hodgkin lymphoma (NHL).

Careful staging of lymphoma is essential, as this provides the basis for treatment decisions. The criteria for NHL staging and the tests used to diagnose, stage, and follow patients should be similar for all patients. Newer therapies and tests need to be considered. Therefore, in 2011 and 2013, a panel of lymphoma experts revised the staging and response criteria for NHL.

This study reviewed the updated recommendations.

Initial diagnosis should include a physical exam and patient history to determine whether B symptoms are present (fever, night sweats, and weight loss). Blood tests should be done.

An FDG-PET-CT scan is recommended for all patients. This type of scan measures glucose uptake by cells. This is faster in lymphoma cells. This scan can determine what areas of the body are involved (spleen, liver, lymph nodes, bone marrow, etc.). It can also be used to measure the size of larger tumors (known as bulky disease). FDG-PET-CT is sensitive enough to diagnose bone marrow involvement in diffuse large B-cell lymphoma (DLBCL). In one study, only 1.5% (2 cases) of bone marrow involvement were missed, while 94% were identified. In DLBCL, bone marrow biopsy is only needed if the scan was negative. 

It is recommended that a treatment plan be based on risk factors and expected progression.

PET-CT can be used to determine treatment response in many cases. In aggressive forms of NHL, a negative PET scan (no sign of disease) predicts outcome 80% to 100% of the time. A positive scan (some remaining disease activity) is less predictive (50% to 100%). Biopsy or another scan is recommended.

A 5-point scale is recommended to evaluate scans. A score of 1 or 2 represents a complete response (no sign of disease). A score of 4 or 5 would indicate partial response if the scan is done during treatment, or treatment failure if the scan is done at the end of treatment. If it appears that there is disease progression, the area should be checked after at least 2 weeks to determine if there is actual disease progression.

DLBCL is considered a curable form of NHL. For DLBCL, follow-ups should occur every 3 months for 2 years, ever 6 months for 3 years, then every year. This risk of relapse decreases over time. For more aggressive subtypes, such as follicular or mantle cell lymphoma, the likelihood of relapse increases over time. These patients should be examined every 3 to 6 months. Routine surveillance scans are not recommended, unless there is a concern about remaining disease in the abdominal area.

This study provided updated guidelines and recommendations for the staging and follow-up of patients with non-Hodgkin lymphoma (NHL).