Diabetic cancer patients respond less to immuno-oncological treatments. In particular, in these people metabolic disease is associated with worse survival and the risk of tumor progression increases by 20% compared to non-diabetic cancer patients. This is demonstrated by a study, coordinated by Imperial College London and the Campus Bio-Medico University Hospital Foundation in Rome, which involved about 1,400 people affected by advanced solid tumors and treated with immuno-oncological drugs in 21 centres. The results of the research, published in Clinical Cancer Research, are illustrated in the conference ‘Cancer research: from Orlando to Palermo news from AACR Annual Meeting’ organized by the Italian Association of Medical Oncology (Aiom) in Palermo.
“In the past, some research had highlighted the so-called ‘obesity paradox’, because it seemed that being overweight could favor the effectiveness of therapies that stimulate the immune system against cancer cells – says Saverio Cinieri, president of Aiom -. This study, for the first time in the world, highlights how diabetic patients, who are often overweight or obese, instead represent a subgroup that benefits less from immuno-oncological treatments, with a reduced survival.Obesity can include several specific conditions, among diabetes. The study showed that the tumor microenvironment of diabetic people has characteristics of greater ‘immune exhaustion’ and immunosuppression”.
“We have reconstructed the concomitant diagnosis of type 2 diabetes mellitus, which affected 16% of the study population – underlines Alessio Cortellini, oncologist of the Campus Bio-Medico University Hospital Foundation in Rome and first author of the study -. We have demonstrated that the patients diabetics, treated with immuno-oncological molecules, obtain reduced efficacy and survival results compared to the general population”.
Therefore, notes Antonio Russo, professor of Medical Oncology at the University of Palermo “obesity is a serious oncological risk factor, which induces a state of chronic systemic inflammation, with a reduction in the activity of the immune system and more studies are needed to investigate the complex relationship between metabolism, body composition, immune system and tumors, with particular attention to cancer patients with a concomitant diagnosis of diabetes, who must start immunotherapy treatment”. In 2022, in Italy, 390,700 new cancer diagnoses were estimated, in constant growth also due to the spread of incorrect lifestyles. Excess weight represents an important cardiovascular and oncological risk factor and, in our country, this condition affects 4 out of 10 adults: 33% of citizens are overweight and 10% are obese.
“According to estimates by the World Cancer Research Fund, about a fifth of cancer cases are attributable to an energy balance that is too rich – concludes Saverio Cinieri -. Fat is a natural deposit of substances that promote systemic inflammation and produces hormones, such as estrogens, involved in various types of cancer.Scientific researches have linked obesity and overweight to as many as 13 different types of cancer and the possible genetic relationships between obesity, cancer and metabolic syndrome have also been examined.Adipose tissue is composed not only of fat cells but also by cells of the immune system that allow us to burn our energy at the right moment.In overweight or obese individuals, these cells are ‘disoriented’ and send the wrong messages to the body.Hence the greater risk of developing cancer. It is important that all citizens are made aware of the importance of adopting healthy lifestyles, with a correct diet and constant physical activity”.