Related Experiment Video
Updated: Feb 4, 2026

Injection of Syngeneic Murine Melanoma Cells to Determine Their Metastatic Potential in the Lungs
Published on: May 24, 2016
Body mass index may predict the response to ipilimumab in metastatic melanoma: An observational multi-centre study
Georg Richtig1,2, Christoph Hoeller3, Martin Wolf2,4
1Otto Loewi Research Center, Pharmacology Section, Medical University of Graz, Graz, Austria.
Introduction:
Immunotherapy is a well-established treatment option in patients with metastatic melanoma. However, biomarkers that can be used to predict a response in these patients have not yet been found, putting patients at risk of severe side effects.
Methods:
In this retrospective analysis, we investigated the association between the body mass index and ipilimumab treatment response in patients with metastatic melanoma. Patients with metastatic melanoma who received a monotherapy of up to 4 doses of ipilimumab (3 mg/kg) every 3 weeks from 2011 to 2014 in three major hospitals in Austria were included. Patients were classified into two groups: normal group (BMI<25) and overweight group (BMI≥25).
Results:
40 patients had a normal BMI, and 36 had a BMI above normal. Patients with a BMI that was above normal showed significantly higher response rates (p = 0.024, χ2), and lower likelihood of brain metastases (p = 0.012, χ2). No differences were found between both groups with respect to gender (p = 0.324, χ2), T-stage (p = 0.197, χ2), or the occurrence of side effects (p = 0.646, χ2). Patients with a BMI above normal showed a trend towards longer overall survival (p = 0.056, Log-Rank), but no difference was found regarding progression-free survival (p = 0.924, Log-Rank).
Conclusions:
The BMI correlated with the response to ipilimumab treatment in a cohort of metastatic melanoma patients.
Related Concept Videos
Observational Studies
There are three types of observational studies – Prospective, retrospective, and cross-sectional.
Prospective Study
Prospective studies, also known as longitudinal or cohort studies, are carried out by collecting future data from groups sharing similar characteristics. One...
Reduced Mass Coordinates: Isolated Two-body Problem
Naturalistic Observations
Predicting Molecular Geometry
Prediction Intervals
However, the point estimate is most likely not the exact value of the population parameter, but close to it. After calculating point estimates, we construct interval estimates, called confidence intervals or prediction intervals. This prediction interval comprises a range of values unlike the point estimate and is a better predictor of the observed sample value, y.
Observational Learning

