Predictive factors of survival of colorectal cancer patients after para-aortic lymph node metastasis

Background Para-aortic lymph node (PALN) metastasis is an ominous manifestation indicating a poor prognosis in colorectal cancer (CRC) patients; however, some treatments prolong survival. In this study, we investigated predictors of prolonged survival in CRC patients after PALN metastasis. Methods We examined 141 patients with CRC that metastasized to the PALNs from CRC with or without extra-PALN metastasis. Among clinicopathological parameters, factors associated with survival after PALN metastasis were identified by multivariate analyses using Cox’s proportional hazard models. Results The mean hemoglobin and albumin values at diagnosis were 12.3 g/dL and 3.7 g/dL, respectively. Rectal cancer was predominant ( n = 81). Mutated RAS was detected in 43%. One hundred and four patients had differentiated adenocarcinoma. Patients underwent PALN dissection ( n = 11), radiotherapy ( n = 6), and systemic therapy ( n = 120). Biologics were administered to 95 patients. The median survival time was 29.1 months. On multivariate analysis, independent factors associated with reduced survival after PALN metastasis were low albumin (hazard ratio [HR] 2.33 per −1 g/dL), mutated RAS (HR 2.55), other than differentiated adenocarcinoma (HR 2.75), rectal cancer (HR 3.38 against right-sided colon, and 3.48 against left-sided colon), the presence of extra-PALN metastasis (HR 6.56), and no use of biologics (HR 3.04). Conclusions This study revealed that hypoalbuminemia as well as RAS mutation, undifferentiated histology, rectal cancer, other site metastasis, and no use of biologics contribute to poor prognosis in CRC patients with PALN metastasis. Nutritional management may be important for improving survival of these patients.