NLR (Neutrophil-to-Lymphocyte Ratio)

A powerful prognostic ratio in oncology — reflects systemic immune balance.

What it is

NLR is calculated by dividing the absolute neutrophil count by the absolute lymphocyte count. It reflects the balance between the pro-inflammatory (neutrophil) and adaptive immune (lymphocyte) arms of the immune system.

Why it matters

NLR is one of the most extensively studied prognostic markers in oncology. Elevated NLR before or during treatment consistently predicts worse outcomes across many cancer types. A falling NLR — more lymphocytes, fewer neutrophils — reflects a healthier immune environment and better treatment response.

How to test

Calculated from full blood count differential (NEUT# ÷ Lymph#).

This information is for educational purposes only. Always discuss testing and interpretation of results with your care team.

Optimal range

Below 3

favourable — healthy immune balance

3–5

borderline

Above 5

elevated — associated with poorer prognosis

How often

Each blood count panel. Track trend over treatment cycles.