Impact of Skeletal Muscle-related Parameters on Survival in Patients with Advanced Pancreatic Cancer Treated with Gemcitabine plus Nab-paclitaxel as First-line Chemotherapy.

BACKGROUND

Sarcopenia, defined as a reduction in muscle mass assessed using scales such as the psoas muscle mass index (PMI), is accompanied by decreased muscle strength or physical function. However, sarcopenia's effect in patients with pancreatic cancer (PC) receiving chemotherapy remains unclear. In addition, recent international studies have demonstrated that intramuscular fat infiltration, assessed using parameters such as FRPM, is associated with poor prognosis across various malignancies. However, evidence regarding its prognostic significance in pancreatic cancer remains limited. We aimed to evaluate the relationship between sarcopenia and the prognosis of patients with PC receiving palliative chemotherapy.

METHODS

We retrospectively reviewed patients diagnosed with unresectable PC who received gemcitabine plus nab-paclitaxel (GnP) as the first-line therapy at our hospital between 2018 and 2021. We calculated PMI, defined as the sum of the bilateral psoas muscle mass at the lumbar three (L3) level and FRPM, defined as the sum of areas within the psoas muscles corresponding to fat at the L3 level from Vincent® on the CT images. We compared the overall survival (OS) between the PMI-high and PMI-low groups and the FRPM-high and FRPM-low groups.

RESULTS

Of 46 patients, 37 were eligible. Eighteen (49%) and 19 (51 %) patients were classified into PMI-high and PMI-low groups, respectively. Twenty (54%) and 17 patients (46%) were classified into FRPM-high and FRPM-low groups, respectively. The median OS was 16.4 months in PMI-high and 8.7 months in PMI-low groups (hazard ratio [HR]: 0.45, 95% confidence interval [CI]: 0.23-0.90, P < 0.01). The median OS was 15.6 months in FRPM-low and 8.5 months in FRPM-high groups (HR: 0.36, 95% CI: 0.18-0.76, P < 0.01). In multivariate analysis, the presence of ascites (P < 0.01), PMI-low (P = 0.02), and FRPM-high (P = 0.03) were independent adverse prognostic factors for OS.

CONCLUSION

Muscle-related parameters may be independent indicators of poor prognosis in patients with PC treated with first-line GnPs.