Loss of Skeletal Muscle Mass During Neoadjuvant Chemotherapy for Pancreatic Cancer Is Related to the Continuation of S-1 Adjuvant Chemotherapy After Pancreatectomy

Abstract

Background/aim: Although perioperative chemotherapy has improved patient survival, sarcopenia may occur during chemotherapy owing to decreased food intake and physical strength. However, reports on the occurrence of sarcopenia and changes in body composition in patients with pancreatic cancer during neoadjuvant chemotherapy are scarce. This study aimed to determine the effect of changes in skeletal muscle mass during neoadjuvant chemotherapy on the S-1 adjuvant chemotherapy clinical course in patients who underwent perioperative chemotherapy and surgical resection.

Patients and methods: We retrospectively enrolled 159 patients with pancreatic cancer who underwent neoadjuvant chemotherapy and surgical resection, followed by S-1 adjuvant chemotherapy. We evaluated changes in skeletal muscle mass during neoadjuvant chemotherapy using abdominal computed tomography and the SliceOmatic software. The association between the rate of change in skeletal muscle mass index (Δ%SMI) during neoadjuvant chemotherapy and the continuation of S-1 adjuvant chemotherapy was investigated.

Results: Eighty-eight (55.3%) patients lost skeletal muscle mass (Δ%SMI <0) during neoadjuvant chemotherapy with a significantly low S-1 adjuvant completion rate (p=0.02). Δ%SMI <0 was an independent risk factor for the continuation of S-1 adjuvant chemotherapy (hazard ratio=1.924, 95% confidence interval=1.002-3.695, p=0.049). Moreover, the lower the Δ%SMI, the lower the S-1 continuation rate (p=0.022).

Conclusion: Loss of skeletal muscle mass during neoadjuvant chemotherapy for pancreatic cancer affected the continuation of S-1 adjuvant chemotherapy after pancreatic resection. Therefore, ameliorating loss of skeletal muscle mass during neoadjuvant chemotherapy should be carefully considered to improve the continuation rate of adjuvant chemotherapy and the survival of patients with pancreatic cancer.

Keywords: Pancreatic cancer; S-1; SMI; continuation; neoadjuvant chemotherapy; risk factor; skeletal muscle mass.