Does body-mass index (BMI) affect survival in patients with metastatic melanoma?

This study investigated whether body-mass index (BMI) had any effect on survival in patients with metastatic melanoma who received targeted therapy, immunotherapy, or chemotherapy. The study found that male metastatic melanoma patients who had a high BMI had improved survival compared to patients with normal BMI.

Targeted therapies (drugs aimed specifically at cancer cells) and immune therapies (drugs that activate immune system to kill cancer) have improved survival in metastatic melanoma patients. However, some patients do not respond well to treatment. Obesity (high BMI) has been linked to increased death in several cancer types but also improved survival in some cancers. The relationship between obesity and survival in metastatic melanoma is unknown. It is important to understand if BMI can affect response to different treatments in metastatic melanoma patients so the most effective treatments can be chosen for patients.

This study analysed data from 6 different groups of metastatic melanoma patients (1918 patients in total). Two patient groups received targeted therapy of [dabrafenib (Tafinlar) and trametinib (Mekinist)] and [Vemurafenib (Zelboraf) and cobimetinib (Cotellic)], two patient groups received immunotherapy [ipilimumab (Yervoy) + dacarbazine (DTIC-Dome)], one patient group was treated with anti-PD-1/PDL-1 (drug that activates immune cells to kill cancer), and two patient groups were treated with chemotherapy. BMI was classified as normal (BMI 18 to 25), overweight (25-29.9) or obese (≥30). The study examined if there was a relationship between BMI, progression free survival (PFS – surivival without worsening of disease), and overall survival (OS). The study also examined if gender (male or female) or treatment type (targeted, immunotherapy, chemotherapy) affected BMI relationship to survival.

Obese metastatic melanoma patients (BMI ≥30) had a 23% improvement in PFSand 26% improvement in overall survival compared to patients with normal BMI.This survival benefit was seen in obese patients treated with targeted or immunotherapy but not chemotherapy and was only seen in male metastatic melanoma patients, not in female patients.

The study concluded that a high BMI was associated with improved survival in male metastatic melanoma patients treated with targeted or immune therapy.  

This study analysed data collected from 6 different patient groupswhci hmay affect data and results may require research with a larger study.  

Talk to your doctor about the impact of BMI on different types of cancer treatment.