A comprehensive investigation into the metabolic pathways of renal cell carcinoma – the MetKid project

This project provided a better understanding of the metabolic processes by which obesity, hypertension and other associated conditions, as well as B vitamins, influence the risk of kidney cancer

  • Topic: Kidney cancer
  • Institution: International Agency for Research on Cancer (IARC)
  • Country: France
  • Status: Completed
Researcher: Mattias Johansson


Obesity increases the risk of developing renal cancer, a cancer that yearly causes 110,000 deaths worldwide. However, our understanding of the underlying biological mechanisms that link obesity to a high renal cancer risk are largely unknown.

Aims and objectives

This project aimed to improve our understanding of why obesity is important in renal cancer, specifically by identifying so-called mediating factors that can give us clues to the underlying mechanisms.

How the study was done

We analysed blood plasma samples from renal cancer patients donated up to 15 years before receiving their diagnosis, and compared them with paired individuals who remained cancer-free. In total, 700 renal cancer patients and comparable controls were included. We used a targeted metabolomics approach to measure concentrations of 150 individual metabolites.

Standard statistical methods were used to compare the cancer cases and controls to identify individual metabolites linked to risk of the disease, and evaluate if they could explain mechanisms underlying associations between previously identified risk factors and renal cancer. We also used more advanced statistical procedures to identify metabolic profiles that may indicate broader disease pathways and mechanisms.


This project strongly suggests that obesity causes a bigger increased risk than previously thought. Furthermore, we specifically identified diastolic blood pressure and insulin as likely to be involved in the reason why obesity increases the risk of renal cancer.