Current status of research on sarcopenia in post-treatment cancer survivors in Japan:A narrative review.

Sarcopenia is prevalent among 11-25% of adult cancer survivors, depending on the cancer type, although the available data on post-treatment survivors in Japan are limited. If cancer patients develop cachexia, they may experience sustained weight loss as a result, ultimately leading to sarcopenia. Conversely, some patients experience post-treatment weight gain, resulting in sarcopenic obesity. Both sarcopenia and obesity elevate the risk of cardiovascular diseases and mortality; therefore, the importance of sarcopenia prevention and management is undeniable. The Guidelines for Exercise for Cancer Survivors recommend continued physical activity. Recent studies have reported the effectiveness of multimodal interventions, combining pharmacological, nutritional, and exercise approaches, necessitating multidisciplinary care for post-treatment sarcopenia. Innovative health interventions using mobile devices have also gained attention. However, studies on sarcopenia in post-treatment cancer survivors, especially those regarding exercise interventions, remain scarce in Japan, primarily due to limited insurance coverage for such post-treatment interventions and workforce challenges. It is clear that some cancer survivors have sarcopenia, which can lead to worse survival and secondary illness. While the benefits of exercise are clear, a comprehensive approach to sarcopenia is a further challenge for the future.