MAGENT

MIPI: how the simplified Mantle Cell Lymphoma International Prognostic Index is scored

The simplified MIPI adds points for four factors in mantle cell lymphoma: age, ECOG performance status, LDH as a ratio of its upper limit of normal, and white blood cell count. The total runs from 0 to 11 and falls into a low (0–3), intermediate (4–5) or high (6–11) risk group.

Not a medical device. Not a diagnosis or dosing recommendation.

Use this calculator via API

What is the MIPI?

MIPI stands for Mantle Cell Lymphoma International Prognostic Index. Eva Hoster, Martin Dreyling, Wolfram Klapper and colleagues published it in Blood in 2008 for advanced-stage mantle cell lymphoma (MCL). The paper gave a continuous formula and a simplified point version; Magent's calculator is the simplified one.

The calculator assigns points for each factor, adds them, and returns a risk_group: low, intermediate or high.

This page explains the arithmetic. It doesn't say what a score means for a particular person.

The simplified MIPI formula

Age             <50 → 0 · 50–59 → 1 · 60–69 → 2 · ≥70 → 3
ECOG            0–1 → 0 · 2–4 → 2
LDH ÷ ULN       <0.67 → 0 · 0.67 to <1.0 → 1 · 1.0 to <1.5 → 2 · ≥1.5 → 3
WBC (×10^9/L)   <6.7 → 0 · 6.7 to <10 → 1 · 10 to <15 → 2 · ≥15 → 3
simplified MIPI = sum · maximum 11
low 0–3 · intermediate 4–5 · high 6–11

Exact expression the calculator uses:

simplified MIPI = age (<50 0, 50–59 1, 60–69 2, ≥70 3) + ECOG (0–1 0, 2–4 2) + LDH/ULN (<0.67 0, 0.67–<1.0 1, 1.0–<1.5 2, ≥1.5 3) + WBC ×10^9/L (<6.7 0, 6.7–<10 1, 10–<15 2, ≥15 3); Hoster 2008; max 11; low 0-3, intermediate 4-5, high 6-11

Inputs

InputMeaningAccepted range
ageAge in years, a whole number18 to 120
ecogECOG performance status, as you assign it0 to 4
ldh_uln_ratioSerum LDH divided by the lab's upper limit of normal0.1 to 20
wbc_k_ulWhite blood cell count in 10^3/µL (same number as 10^9/L)0.01 to 500
wbc_ulOr white blood cell count in cells/µL; divided by 100010 to 500000

How the scoring works

  1. Age: under 50 scores 0; 50 to 59 scores 1; 60 to 69 scores 2; 70 or over scores 3.
  2. ECOG: 0 or 1 scores 0; 2, 3 or 4 scores 2. There's no 1-point step.
  3. LDH ratio: divide serum LDH by the lab's upper limit of normal. Under 0.67 scores 0; 0.67 up to just under 1.0 scores 1; 1.0 up to just under 1.5 scores 2; 1.5 or more scores 3.
  4. White cell count in × 10^9/L: under 6.7 scores 0; 6.7 up to just under 10 scores 1; 10 up to just under 15 scores 2; 15 or more scores 3.
  5. Add the four items for a total from 0 to 11.
  6. Group: 0–3 low, 4–5 intermediate, 6–11 high.

Each lower edge belongs to the higher step: an LDH ratio of exactly 1.0 scores 2, and a white cell count of exactly 10 scores 2.

Units

Age is in whole years. LDH goes in as a ratio to the lab's upper limit of normal, so the lab's own units don't matter. White cell count can be given in 10^3/µL (the same number as × 10^9/L) or in cells/µL, which the calculator divides by 1000. Give one or the other, not both. A missing value or one outside its range is rejected with an error.

Worked examples

These use Magent's own expected values for the calculator. The baseline is age 40, ECOG 0, LDH ratio 0.5 and white cell count 5 × 10^9/L, which scores 0.

Example 1: the baseline

  1. Age 40 → 0; ECOG 0 → 0; LDH ratio 0.5 → 0; white cell count 5 → 0.
  2. Total 0 → low.

Example 2: one factor at a time

  1. Age 50 → 1. Age 60 → 2. Age 70 → 3.
  2. ECOG 2 → 2.
  3. LDH ratio 0.67 → 1. LDH ratio 1.5 → 3.
  4. White cell count 6.7 → 1. White cell count 15 → 3.

Example 3: age 70, ECOG 0, LDH ratio 0.67, white cell count 5

  1. 3 + 0 + 1 + 0 = 4.
  2. intermediate.

Example 4: age 70, ECOG 2, LDH ratio 0.67, white cell count 5

  1. 3 + 2 + 1 + 0 = 6.
  2. high.

Example 5: age 70, ECOG 4, LDH ratio 1.5, white cell count 15

  1. 3 + 2 + 3 + 3 = 11, the maximum.
  2. high.

History of the MIPI

The index comes from Hoster E, Dreyling M, Klapper W and colleagues, A new prognostic index (MIPI) for patients with advanced-stage mantle cell lymphoma, Blood, 2008 (volume 111, issue 2, pages 558–565). The abstract describes patients with advanced-stage mantle cell lymphoma enrolled in clinical trials. In this group, the IPI and the FLIPI separated survival poorly. Four independent prognostic factors were identified (age, performance status, LDH and leukocyte count), and Ki-67 was looked at in an exploratory way.

When it's used

The MIPI was built for advanced-stage mantle cell lymphoma and draws on values usually on hand when the disease is first assessed.

Where it's used

The inputs are age, a performance status rating and two blood tests: LDH with its lab reference limit, and a white cell count.

Who uses it

The person using the calculator assigns the ECOG status and enters age, the LDH ratio and the white cell count. The calculator applies the steps and adds the points.

Limits of the calculation

  • The calculator doesn't assign ECOG, measure LDH or count white cells. Every input comes from the person entering it.
  • It's the simplified MIPI. It isn't the continuous MIPI formula with log10 of the white cell count, and it isn't MIPI-c, which adds Ki-67.
  • The risk group is a label for a range of totals. It doesn't choose a course of care.
  • This page doesn't say what to do with a score.

Clinical decisions belong to a qualified clinician who knows the patient.

  • IPI is the Shipp five-factor International Prognostic Index for aggressive lymphoma.
  • FLIPI is the Follicular Lymphoma International Prognostic Index.
  • CLL-IPI is the prognostic index for chronic lymphocytic leukemia.

Glossary

  • Mantle cell lymphoma (MCL): the B-cell lymphoma the MIPI was built for.
  • ECOG performance status: a 0 to 4 rating of daily functioning.
  • LDH ÷ ULN: serum lactate dehydrogenase divided by the lab's upper limit of normal.
  • WBC: white blood cell (leukocyte) count, in × 10^9/L.
  • Ki-67: a marker of cell growth, used in MIPI-c but not here.

Common mistakes

  • Entering raw LDH. Enter the ratio to the upper limit of normal.
  • Mixing count units. 5 × 10^3/µL and 5000 cells/µL are the same count; use the matching input.
  • Scoring ECOG 1. ECOG 0 and 1 both score 0.
  • Using the continuous formula's numbers. This calculator applies the point steps.

Source

Hoster E, Dreyling M, Klapper W, et al. A new prognostic index (MIPI) for patients with advanced-stage mantle cell lymphoma. Blood. 2008;111(2):558-565. DOI: 10.1182/blood-2007-06-095331. PMID: 17962512

Frequently asked questions

How is the simplified MIPI calculated?

Add points for age (0 to 3), ECOG (0 or 2), LDH ratio (0 to 3) and white cell count (0 to 3).

What are the MIPI risk groups?

0–3 low, 4–5 intermediate and 6–11 high.

What is the difference between the simplified MIPI and the continuous MIPI?

The continuous MIPI is a formula that uses log10 of the white cell count. The simplified MIPI turns each factor into points, and that is what this calculator returns.

What is the highest MIPI score?

11.

Can I enter the white cell count in cells/µL?

Yes. Use the cells/µL input; the calculator divides by 1000.