Review the International Prognostic Index (IPI) and related prognostic context for diffuse large B-cell lymphoma.
The DLBCL IPI (International Prognostic Index) Prognosis Calculator estimates outcomes for patients with diffuse large B-cell lymphoma — the most common aggressive non-Hodgkin lymphoma, accounting for approximately 30–40% of all NHL cases. The IPI, developed in 1993 from a study of 2,031 patients, remains the most widely used prognostic tool in aggressive lymphoma.
The index evaluates five independent adverse prognostic factors: age over 60, advanced stage (III/IV), elevated LDH, poor performance status (ECOG ≥2), and more than one extranodal site. Each factor adds one point, generating a score from 0–5 that classifies patients into four risk groups with distinct expected outcomes in terms of complete response rates and overall survival.
This worksheet compares the original IPI and the revised IPI so the published prognostic context stays visible alongside cell-of-origin notes. It also incorporates cell-of-origin subtyping (GCB vs. non-GCB/ABC), which has emerged as an important prognostic and treatment-guiding biomarker.
The IPI helps organize published prognostic context and can support treatment discussions, follow-up planning, and clinical trial consideration. It should be interpreted alongside pathology, molecular findings, and the overall treatment plan.
IPI Score = Sum of 5 adverse factors (1 point each): • Age > 60 years: +1 • Ann Arbor Stage III or IV: +1 • Serum LDH > upper limit of normal: +1 • ECOG Performance Status ≥ 2: +1 • > 1 extranodal site: +1 Risk Groups: Low (0–1), Low-Intermediate (2), High-Intermediate (3), High (4–5)
Result: IPI Score: 3/5 — High-Intermediate Risk
Age >60 (+1) + Stage III (+1) + LDH >ULN (+1) + ECOG <2 (0) + ≤1 extranodal site (0) = 3 points. High-Intermediate risk group with expected 5-year OS of 43% and CR rate of 55%. In the R-IPI era, this falls in the Poor category with 4-year OS of approximately 55%.
The IPI was originally developed in 1993 from 2,031 patients treated with anthracycline-based chemotherapy (CHOP) before the rituximab era. With the addition of rituximab (R-CHOP) as standard of care in the early 2000s, outcomes improved substantially, and the R-IPI was developed to better discriminate risk groups in the modern treatment era. Some newer models (NCCN-IPI) use more refined age and LDH thresholds for improved prognostication.
Beyond the IPI, molecular characteristics increasingly guide treatment decisions. High-grade B-cell lymphoma with MYC and BCL2 rearrangements (double-hit) requires intensified therapy. ABC/non-GCB subtype may benefit from BTK inhibitors (ibrutinib) or immunomodulatory agents (lenalidomide) added to R-CHOP. Ongoing clinical trials are investigating subtype-directed therapy to improve outcomes in high-risk groups.
Recent advances include: polatuzumab vedotin + R-CHP (POLARIX trial — improved PFS vs. R-CHOP), CAR-T cell therapy for relapsed/refractory disease (axicabtagene ciloleucel, tisagenlecleucel, lisocabtagene maraleucel), bispecific antibodies (glofitamab, epcoritamab, mosunetuzumab), and antibody-drug conjugates (loncastuximab tesirine). These have transformed the treatment landscape for patients who relapse after initial therapy.
Last updated:
This worksheet applies the published IPI and R-IPI factor sets to summarize prognostic context in DLBCL. It is meant for comparison and discussion, not as a treatment recommendation or a substitute for hematology/oncology review.
Diffuse Large B-Cell Lymphoma (DLBCL) is the most common type of aggressive (fast-growing) non-Hodgkin lymphoma, accounting for 30–40% of all NHL cases. It arises from mature B lymphocytes and typically presents as rapidly enlarging lymph nodes, often with systemic symptoms (fever, night sweats, weight loss). Despite its aggressive nature, DLBCL is curable in 60–70% of cases with standard immunochemotherapy.
R-CHOP (rituximab + cyclophosphamide, doxorubicin, vincristine, prednisone) given every 21 days for 6 cycles is the standard first-line treatment. For limited-stage disease (stages I–II), abbreviated chemotherapy (3–4 cycles) plus involved-field radiation may be used. Polatuzumab vedotin was recently added in first-line (Pola-R-CHP) based on the POLARIX trial.
The IPI predicts the likelihood of complete response to treatment and overall survival at 5 years. Low-risk (0–1 points) patients have 73% 5-year OS and 87% CR rate. High-risk (4–5 points) patients have 26% 5-year OS and 44% CR rate. These figures are from the pre-rituximab era; modern outcomes with R-CHOP are significantly better across all groups.
The revised IPI (R-IPI) was recalibrated for the rituximab era. It uses the same 5 factors but groups patients into 3 categories: Very Good (score 0, 4-year OS 94%), Good (score 1–2, 4-year OS 79%), and Poor (score 3–5, 4-year OS 55%). R-IPI better discriminates outcomes for patients receiving R-CHOP.
DLBCL can be classified by cell of origin into GCB (germinal center B-cell, ~50%) and ABC/non-GCB (activated B-cell, ~35%). GCB subtype has better prognosis with standard R-CHOP. ABC subtype is associated with poorer outcomes and may benefit from targeted therapies (ibrutinib, lenalidomide). Determination is made by immunohistochemistry (Hans algorithm) or gene expression profiling.
Double-hit lymphomas (DHL) harbor concurrent rearrangements of MYC and BCL2 (and/or BCL6), identified by FISH testing. They represent 5–10% of DLBCL and have significantly worse prognosis (5-year OS 30–40%) regardless of IPI score. Treatment typically involves intensified regimens like DA-EPOCH-R rather than standard R-CHOP.