Introduction: Some studies reported that the decrease in skeletal muscle mass worsens the immune and nutritional status and related to the poor prognosis in colorectal cancer. We examined the relationship of skeletal muscle mass, immune and nutritional index, and outcome in patients with colorectal cancer at our hospital.
Subjects and methods: We retrospectively analyzed 196 patients of cStageⅡ andⅢ colorectal cancer who underwent curative surgery in our institution between 2007 and 2013. The cross-sectional area of the psoas muscle at the level of the third lumbar vertebra on preoperative computed tomography was assessed to calculate the psoas muscle index(PMI). Patients are divided into high PMIgroup(H-group)and low PMIgroup (L-group)with cut off value(6.36 cm / / 2/m2 for males and 3.92 cm2/m2 for females). Patient background, tumor factor, overall survival(OS), recurrence free survival(RFS)were examined retrospectively.
Results: There were 119 cases in H-group and 77 cases in L-group. Significant differences were recognized in gender, age, Alb value, BMI, and adjuvant chemotherapy between 2 groups. The 5-year survival rate was significantly different from 82.8% in H-group and 70.3% in L-group(p<0.01). The 5-year recurrence-free survival rate was 74.0%in the H-group, and 68.3%in the L-group (p=0.46). Univariate and multivariate analysis showed that age(OR: 1.90, p<0.01), high CEA(OR: 0.012, p<0.05), depth of invasion(OR: 2.19, p<0.05), lymph node metastasis(OR: 2.21, p<0.01), and preoperative low PMI(OR: 2.05, p<0.01), were significantly related to decrease of OS.
Conclusion: Preoperative PMIsuggested to become prognostic factors in Stage Ⅱ and Ⅲ colorectal cancer.