Prognostic Role of Pretreatment Nutritional and Inflammatory Status in Unresectable Metastatic Colorectal Cancer: Supplementary Analysis of JCOG1007.

BACKGROUND

Primary tumor resection (PTR) is not routinely recommended for asymptomatic patients with unresectable stage IV colorectal cancer, based on the results from the Japan Clinical Oncology Group (JCOG)-1007 trial, which showed no survival benefit over upfront chemotherapy. However, host-related factors such as nutritional status and systemic inflammation may impact on treatment outcomes. We conducted a supplementary analysis of JCOG1007 to evaluate whether pretreatment modified Glasgow Prognostic Score (mGPS), albumin, and C-reactive protein were associated with differential outcomes after upfront PTR.

METHODS

Patients registered in JCOG1007 were stratified according to pretreatment mGPS (0, 1, 2), albumin (<3.5 vs. ≥3.5 g/dL), and C-reactive protein (≤1.0 vs. >1.0 mg/dL). Overall survival and progression-free survival (PFS) were assessed using Kaplan-Meier analysis and Cox proportional hazards models. Univariable and multivariable analyses were performed within each subgroup.

RESULTS

Among 165 patients enrolled in JCOG1007, 154 patients without missing data were included for analysis. Patients with impaired host status, such as mGPS 2 and hypoalbuminemia, tended to have shorter overall survival and PFS after PTR than after chemotherapy alone, whereas no apparent differences were observed in other subgroups. In the mGPS 2 subgroup, PTR remained independently associated with worse PFS in multivariable analysis (hazard ratio 3.561; 95% confidence interval 1.005-12.621; P = 0.049), whereas a similar trend was observed in patients with hypoalbuminemia.

CONCLUSIONS

Pretreatment nutritional and inflammatory status did not identify a patient population that may benefit from PTR. These findings further support avoiding routine PTR, regardless of host status.