Review published in Advances in Nutrition underscores lack of large, randomized trials to guide nutrition interventions among people with lung cancer.

In 2020, lung cancer was the second most diagnosed cancer and the leading cause of cancer-related deaths globally, representing 11.4% of all new cancer diagnoses and 18% of all cancer-related deaths.

According to the authors of Current Insights in Nutrition Assessment and Intervention for Malnutrition or Muscle Loss in People with Lung Cancer, a scientific review published in Advances in Nutrition, “up to 70% of people with lung cancer may be affected by cancer-related malnutrition or muscle loss, depending on treatment modality and disease stage.”  Moreover, the authors noted that over the last five years treatments for lung cancer have changed significantly, with implications for nutrition management.  In response, the authors examined research studies published within the last five years that explore malnutrition and muscle loss among people with lung cancer as well as nutritional and multimodal interventions to treat these conditions.

The authors noted that weight loss at the time of diagnosis and over the course of treatment is well established among people with lung cancer.  However, they pointed out that the rising prevalence of overweight and obesity may complicate the identification of underlying weight or muscle loss, which may be signs of malnutrition.

According to the authors, “the adverse outcomes associated with cancer-related malnutrition in people with lung cancer, including reduced survival, poorer quality of life and impaired physical function, have been well documented.”  Nonetheless, the authors were unable to identify studies investigating the prevalence or impact of malnutrition in people receiving immunotherapy for lung cancer, even though more and more patients with lung cancer are now treated with immunotherapy.  The authors did, however, point to a systematic review and meta-analysis of 52 randomized controlled trials among patients with non-small cell lung cancer that found significantly higher incidence of colitis in patients receiving immunotherapy compared to those receiving chemotherapy, a potential sign of increased malnutrition risk.  Given the increased use of immunotherapy among patients with lung cancer, “this remains a crucial area to be explored.”

In addition to malnutrition’s negative impact on lung cancer outcomes, low muscle mass among patients with lung cancer is also associated with poor outcomes.  A 2021 systematic review and meta-analysis, for example, examined 10 studies of people with non-small cell lung cancer who had received lung resections.  Patients with low muscle mass had significantly worse post-operative complications and higher rates of morbidity.

Overall, the authors found that “individualized dietary counselling, increasing protein intake and supplementation with omega-3 fatty acids appear to be beneficial for some, albeit varying, patient outcomes.  Multimodal interventions, generally including a nutrition and exercise component, show promising results; however, the impact on patient outcomes is mixed.”

The authors underscored the lack of large, randomized trials to guide nutrition interventions among people with lung cancer: “Despite the high prevalence of malnutrition and muscle loss in people with lung cancer and the known adverse outcomes, current evidence for nutrition intervention is limited.”  The authors therefore call for a targeted effort “to improve the quality of evidence for nutrition intervention in this population to provide support for clinicians to deliver effective nutrition care.”