FLIPI Score Calculator

FLIPI Score Calculator for Hematology. Scores map to three bands: low risk (0-1), intermediate risk (2), and high risk (3-5). In the original derivation cohort these corresponded to 10-year overall survival of approximately 71%, 51%, and 36%, with the intermediate and high groups carrying hazard ratios of about 2.3 and 4.3 versus low risk. The score does not by itself dictate treatment; a high FLIPI identifies patients for closer surveillance, informed prognostic discussion, and consideration within risk-adapted trial designs, but many high-risk patients still respond well to standard immunochemotherapy.

How this calculator works

The FLIPI (Follicular Lymphoma International Prognostic Index) assigns one point each to five adverse features present at diagnosis: age over 60 years, Ann Arbor stage III-IV, hemoglobin below 120 g/L, more than four involved nodal areas, and serum LDH above the upper limit of normal. The five points are summed (0-5) and collapsed into three risk groups. A useful mnemonic is "NoLASH" (Nodal areas, LDH, Age, Stage, Hemoglobin). It is a purely clinical index requiring no biopsy grading or molecular data.

When to use this calculator

Use FLIPI at diagnosis of grade 1-3A follicular lymphoma to stratify prognosis, counsel patients, and stratify or compare clinical trial cohorts. It was derived largely in a pre-rituximab population but retains prognostic value with immunochemotherapy. It should not be applied to grade 3B follicular lymphoma (treated as diffuse large B-cell lymphoma), to other indolent lymphomas, or as a standalone trigger to start therapy in asymptomatic low-burden disease, where watch-and-wait and GELF/BNLI criteria govern the treatment decision.

Inputs used

  • Age
  • Ann Arbor stage
  • Hemoglobin
  • Nodal areas
  • LDH

Clinical interpretation

Scores map to three bands: low risk (0-1), intermediate risk (2), and high risk (3-5). In the original derivation cohort these corresponded to 10-year overall survival of approximately 71%, 51%, and 36%, with the intermediate and high groups carrying hazard ratios of about 2.3 and 4.3 versus low risk. The score does not by itself dictate treatment; a high FLIPI identifies patients for closer surveillance, informed prognostic discussion, and consideration within risk-adapted trial designs, but many high-risk patients still respond well to standard immunochemotherapy.

Worked example

A 68-year-old with stage IV disease, hemoglobin 115 g/L, six involved nodal areas, and normal LDH scores 4 points: age over 60 (1), stage III-IV (1), hemoglobin under 120 (1), and more than four nodal areas (1), with LDH contributing 0. A total of 4 places the patient in the high-risk group (score 3-5), historically associated with roughly a 50% 10-year overall survival in the derivation cohort.

Limitations and safety notes

FLIPI was built to predict overall survival in a mostly pre-rituximab era, so absolute survival estimates understate outcomes achieved with modern anti-CD20-based regimens. It weights all five factors equally and gives no information on early progression (POD24), which is the strongest modern predictor of poor survival. It omits tumor burden, beta-2-microglobulin, and bone marrow status; FLIPI2 (Federico 2009, using beta-2-microglobulin, longest node diameter over 6 cm, marrow involvement, hemoglobin under 120 g/L, and age over 60) was designed prospectively to better predict progression-free survival. FLIPI does not incorporate m7-FLIPI genetic mutations.

Frequently asked questions

What is the difference between FLIPI and FLIPI2?

FLIPI (2004) was derived retrospectively to predict overall survival and uses number of nodal areas and LDH. FLIPI2 (2009) was built prospectively to predict progression-free survival and replaces those with beta-2-microglobulin, longest involved node over 6 cm, and bone marrow involvement, keeping age over 60 and hemoglobin under 120 g/L. They are complementary rather than interchangeable.

Does a high FLIPI mean the patient needs immediate treatment?

No. FLIPI is prognostic, not a treatment trigger. The decision to treat rests on symptoms and tumor burden (GELF or BNLI criteria). An asymptomatic patient with low disease burden can still be managed with active surveillance even with a high FLIPI.

Is FLIPI still valid in the rituximab era?

Yes, it continues to discriminate risk groups in rituximab-treated cohorts, but the absolute survival figures from the original 1985-1992 cohort are pessimistic compared with contemporary outcomes. Interpret the risk band rather than the historical percentage.

How do I count nodal areas for FLIPI?

FLIPI uses the number of involved nodal areas (more than four is adverse), based on a defined set of peripheral and central lymph node regions plus spleen. This differs from Ann Arbor number of sites and is a common source of miscalculation; standardized region maps should be used.

What does POD24 add that FLIPI does not?

POD24 (progression within 24 months of starting immunochemotherapy) identifies patients with markedly inferior survival and is the strongest post-treatment prognostic marker. FLIPI is a baseline index and cannot capture this; the two are used at different time points.

References

  • Solal-Céligny P, Roy P, Colombat P, et al. Follicular lymphoma international prognostic index. Blood. 2004. PMID: 15126323.
  • Federico M, Bellei M, Marcheselli L, et al. Follicular lymphoma international prognostic index 2: a new prognostic index for follicular lymphoma developed by the international follicular lymphoma prognostic factor project. J Clin Oncol. 2009. PMID: 19652063.

Editorial review and citation methodology

Reviewed by the Quick Medical Calculator Editorial Team. Last reviewed: May 11, 2026. The review checks calculator inputs, intended population, interpretation, limitations, and source alignment.

  • Prefer original validation studies for scoring systems and prediction tools.
  • Use current specialty society guidance, transplant allocation policy, public health guidance, or regulator resources when they govern clinical use.
  • Include limitations and safety notes when a calculator is population-specific, context-dependent, or unsuitable as a standalone decision tool.

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