Latest Cancer TreatmentsDr. Mohammadreza Dabiri
Dr. Mohammadreza Dabiriفارسی
Clinical tool

RECIST 1.1 Tumour Response Calculator

Complete or partial response, stable or progressive disease from the sum of target lesion diameters

Updated: 27 October 20261 min read2 references

Target lesion response by RECIST version 1.1: enter the sum of the longest diameters (short axis for lymph nodes).

This calculator needs JavaScript; the formula and its interpretation are in the text of this page.

An aid for clinicians; it does not replace clinical judgement, local protocols or the drug label. Double-check every result before prescribing.

Key rules

  • Measurable lesion: at least 10 mm (lymph node: short axis 15 mm or more) [1].
  • At most 5 target lesions and 2 per organ [1].
  • CR: disappearance of all lesions and nodes below 10 mm; PR: a decrease of 30% or more from baseline; PD: an increase of 20% or more over the smallest sum and at least 5 mm, or a new lesion; SD: everything else [1].
  • iRECIST: with immunotherapy, the first progression is “unconfirmed” (iUPD) and becomes “confirmed” (iCPD) if it increases further 4–8 weeks later [2].

Full lesson: assessing tumour response.

References

2 references
Show all referencesClose the reference list

Numbers in the text, such as [1], refer to these sources. Sources with a “Study card” button are summarised in the site’s evidence library.

  1. 1
    New response evaluation criteria in solid tumours: revised RECIST guideline (version 1.1)Eisenhauer EA, Therasse P, Bogaerts J, et al · Eur J Cancer · 2009;45:228-47
    DOIPubMed Back to text: 1 2 3
  2. 2
    iRECIST: guidelines for response criteria for use in trials testing immunotherapeuticsSeymour L, Bogaerts J, Perrone A, et al · Lancet Oncol · 2017;18:e143-e152
    DOIPubMed Back to text

This page is based on reputable scientific sources and was last updated on 27 October 2026. The content of this website is for educational and informational purposes only and does not replace consultation, diagnosis or treatment by a specialist physician. Consult your treating physician about any treatment decision.

Printed from the website; the full and up-to-date version: https://drdabiri.com/en/tools/recist-response-calculator/

Related pages

27 October 2026 NNT, Absolute and Relative Risk Reduction Calculator Calculator for the number needed to treat (NNT), absolute risk reduction (ARR) and relative risk reduction (RRR) from the event rates of two trial arms. 27 October 2026 Body Surface Area (BSA) and Chemotherapy Dose Calculator Body surface area calculator (Mosteller and DuBois) with total dose of chemotherapy from mg/m² or mg/kg, and the ASCO recommendation on dosing in obesity. 27 October 2026 Creatinine Clearance and eGFR Calculator Creatinine clearance (Cockcroft-Gault) and eGFR (CKD-EPI 2021) calculator for dosing anticancer drugs in renal impairment.