Although all of the options listed above affect the prognosis of this patient with an aggressive B-cell lymphoma, the revised International Prognostic Index score (r-IPI) correlates most strongly with his chance of overall survival after standard therapy.
Non-Hodgkin lymphoma (NHL) consists of over 20 subtypes defined by cell surface antigen expression and other morphologic features, including unique molecular profiles. The first major distinction divides NHL into three categories based on immunophenotyping to a B-cell, T-cell, or natural killer (NK) cell lineage. B-cell lymphomas account for 85% of all cases of NHL, T-cell lymphomas for 13%, and NK-cell lymphomas for 2%. A history of farming is not uncommon among newly diagnosed patients with B-cell lymphomas because components in some fertilizers are thought to be causative. Staging of lymphoma consists of structural disease assessment using physical examination findings, CT imaging, biopsy findings of potential disease sites, and disease activity assessment using PET scanning to quantify the standard uptake value. Age, concomitant infection or immunodeficiency, and expression of driver gene mutations can all influence prognoses. The Ann Arbor Staging System criteria can be used for most forms of lymphoma, however, the r-IPI score is most predictive of outcomes in patients with diffuse large B-cell lymphoma. The r-IPI incorporates multiple clinical factors, including the patient's age, performance status, disease stage, degree of extranodal involvement, and serum lactate dehydrogenase level to generate a score that correlates with progression-free and overall survival after standard therapy. This patient has a high r-IPI score due to stage IV disease (bone marrow involvement), a high serum lactate dehydrogenase level, and poor performance status.
The presence of anemia and B symptoms might be indicative of aggressive disease, but are not incorporated into the r-IPI score, which is the best predictor of clinical outcome.
The presence of diabetes appears to have a minimal effect on the outcome of lymphoma and is therefore not an independent predictive factor.