Pan-Immune-Inflammation Value (PIV) Calculator
Pan-Immune-Inflammation Value (PIV) Calculator
Calculate PIV from all four cell lines — and know which units you are in before you compare the answer with anything. The published convention and the per-microlitre one differ by a factor of a million.
Pan-Immune-Inflammation Value (PIV)
N × P × M ÷ LNeutrophils 4.8, platelets 265, monocytes 0.55, lymphocytes 1.6 (all ×10⁹/L)
The formula, and the unit convention it must be read in
all four counts in ×10⁹/L (= ×10³/µL = 10³/mm³)
PIV in cells/µL = PIV in ×10⁹/L × 1,000,000
- the original units
- Fucà and colleagues defined it as “[neutrophil count (10³/mmc) × platelet count (10³/mmc) × monocyte count (10³/mmc)]/lymphocyte count (10³/mmc)”. 10³/mm³ is 10³/µL is ×10⁹/L — the three are the same number — so the published convention IS the SI one, and this calculator uses it unchanged
- why the factor is 10⁶, not 10³
- going to cells/µL multiplies every count by 1,000. Three counts are in the numerator and one in the denominator, so PIV is multiplied by 1000³ ÷ 1000 = 1,000,000. The same patient scores 437 or 437,250,000
- the platelet term
- this is what separates PIV from SIRI. Platelets carry the thrombo-inflammatory arm — release of platelet-derived growth factors, interaction with circulating tumour cells — that the leucocyte-only indices miss
- no reference interval
- PIV has no population-derived normal range. Every number quoted as a cut-off was chosen, usually by ROC analysis, to optimise a particular cohort’s outcome data
Worked example
Neutrophils 4.8, platelets 265, monocytes 0.55, lymphocytes 1.6 (all ×10⁹/L)
4.8 × 265 = 1,272
1,272 × 0.55 = 699.6
699.6 ÷ 1.6 = 437
Above Fucà's metastatic colorectal cut-off of 390, and inside the 164.6 – 600 span of every cut-off published across 30 studies
Now the same patient in cells/µL: 4,800 × 265,000 × 550 ÷ 1,600 = 437,250,000
A factor of exactly a million, because three of the four counts are in the numerator. Quoting 437,250,000 against a cut-off of 390 — or 437 against a cut-off quoted in the other convention — is not a small error
Published PIV cut-offs, by tumour type
| Tumour type | Range of ‘high PIV’ cut-offs reported |
|---|---|
| Oesophageal | 164.6 – 232.8 |
| Breast | 228 – 306.4 |
| Colorectal | 231 – 492 |
| Lung | 364 – 581.95 |
| Melanoma | 390 – 600 |
| Metastatic colorectal (Fucà et al., the original) | 390 |
The same patient in two conventions
| Convention | Counts entered as | PIV for this worked example |
|---|---|---|
| Published (SI) | 4.8, 265, 0.55, 1.6 ×10⁹/L | 437 |
| Per microlitre | 4,800, 265,000, 550, 1,600 cells/µL | 437,250,000 |
| Factor between them | × 1,000 on each count | × 1,000,000 |
What PIV pools, and what each ratio uses
| Index | Numerator | Denominator | Cell lines |
|---|---|---|---|
| NLR | Neutrophils | Lymphocytes | 2 |
| PLR | Platelets | Lymphocytes | 2 |
| LMR | Lymphocytes | Monocytes | 2 |
| SIRI | Neutrophils × monocytes | Lymphocytes | 3 |
| SII | Platelets × neutrophils | Lymphocytes | 3 |
| PIV | Neutrophils × platelets × monocytes | Lymphocytes | 4 |
Every cell line at once, and a cut-off that belongs to its cohort
The pan-immune-inflammation value multiplies the neutrophil, platelet and monocyte counts together and divides by the lymphocyte count. It is the most inclusive of the composite blood count indices — the only one that uses all four lines — and it was introduced by Fucà and colleagues in 2020 on a pooled analysis of 438 patients with metastatic colorectal cancer from the Valentino and TRIBE first-line trials. In that population, patients above the derived cut-off of 390 had a median overall survival of 21.6 months against 34.4, a hazard ratio of 2.01, and a progression-free survival hazard ratio of 1.66.
What distinguishes it from the systemic immune-inflammation index, which it most resembles, is the monocyte term; what distinguishes it from the systemic inflammation response index is the platelet term. The reasoning is that neutrophils, platelets and monocytes each contribute to a tumour-permissive inflammatory environment while lymphocytes contribute to the anti-tumour response, so folding all four into one number should capture more than any pair of them. In several cohorts it has outperformed NLR, PLR and SII individually. It has not thereby acquired a threshold.
That is the part worth dwelling on. A meta-analysis of thirty studies found the cut-off used to define ‘high PIV’ ranged from 164.6 to 600.0 — a nearly fourfold span — with the ranges overlapping between tumour types and varying threefold within some of them. The pooled hazard ratios are real enough (2.07 for overall survival, 1.83 for progression-free survival) but they come with heterogeneity statistics of 73 and 98 per cent, which is a formal way of saying the included studies are not measuring quite the same thing. Every one of those cut-offs was chosen to optimise separation in the dataset it was derived from. Applying one to a patient in a different disease, at a different stage, is not a transfer the method supports.
The other thing to get right is the units, and here PIV is worse than its siblings. The original paper specifies all four counts in 10³ per cubic millimetre, which is the same number as ×10⁹/L and as ×10³/µL — so the published convention is the SI one and this calculator uses it. But if a reader enters counts in cells per microlitre, three of the four are in the numerator and one in the denominator, and the answer comes out a million times larger. A PIV of 437 and a PIV of 437,250,000 can be the same patient. Any PIV quoted without its convention is uninterpretable, and any cut-off borrowed across conventions is wrong by six orders of magnitude.
Read alongside its relatives, PIV is best understood as one member of a correlated family. Neutrophilia with lymphopenia is the common physiological substrate of all of them, so they move together, and none has been validated as a decision rule for an individual patient. A very high PIV is worth looking at — but look at which term produced it, because a platelet count of 700 and a lymphocyte count of 0.4 give the same index and mean quite different things.
Frequently asked questions
What is the formula for PIV?
Neutrophil count times platelet count times monocyte count, divided by lymphocyte count, with all four as absolute counts. The original paper specifies them in 10³ per cubic millimetre, which is identical to ×10⁹/L and ×10³/µL.
Does it matter which units I use?
Enormously. Three of the four counts are in the numerator, so switching from ×10⁹/L to cells per microlitre multiplies the answer by a million. The same patient is 437 in the published convention and 437,250,000 in the other one.
What counts as a high PIV?
There is no universal answer. The original metastatic colorectal cancer study used 390; a meta-analysis of thirty studies found cut-offs from 164.6 to 600. Each was derived by optimising a particular cohort’s own outcome data and does not transfer to another disease or stage.
How is PIV different from the systemic immune-inflammation index?
SII is platelets times neutrophils over lymphocytes. PIV adds the monocyte count to the numerator, making it the only one of the common indices to use all four cell lines. That is its claimed advantage and also why its numerical range and its unit problem are larger.
Is PIV used in any guideline?
No. It is a prognostic research marker with a substantial observational literature and no validated role as a diagnostic test or a treatment decision rule for an individual patient.
Is there a normal range for PIV?
No population-derived reference interval has been established. The bands on this page describe where a value sits relative to the published literature, which is a different thing from describing whether it is normal.
Related calculators
References
- Fucà G, Guarini V, Antoniotti C, et al. The Pan-Immune-Inflammation Value is a new prognostic biomarker in metastatic colorectal cancer: results from a pooled-analysis of the Valentino and TRIBE first-line trials. Br J Cancer. 2020;123(3):403–409.
- Prognostic significance of the pretreatment pan-immune-inflammation value in cancer patients: an updated meta-analysis of 30 studies. Front Nutr. 2023;10:1259929.
- Hu B, Yang XR, Xu Y, et al. Systemic immune-inflammation index predicts prognosis of patients after curative resection for hepatocellular carcinoma. Clin Cancer Res. 2014;20(23):6212–22.
Medical Disclaimer: The tools and content provided here are for educational and reference purposes only. They are not intended to substitute for professional medical advice, diagnosis, or treatment. Clinical decisions should always be based on the comprehensive assessment of a qualified healthcare professional.
