Prognostic stratification for patients with neuroendocrine tumours receiving 177Lu-Dotatate.

ABSTRACT

177Lu-Dotatate is increasingly used in patients with advanced neuroendocrine tumour (NET). However, few prognostic markers are available to stratify progression-free survival (PFS) of patients who received 177Lu-Dotatate. Clinicopathological data including baseline circulating biomarkers of patients with advanced NET who received 177Lu-Dotatate were routinely collected and were retrospectively analysed. Continuous variables were normalized by dividing them by their upper normal limits. The whole data set was randomly divided into a training set and a validation set. Univariate and multivariate logistic regression analyses were used to identify independent markers and to develop a scoring model to predict treatment failure at 1 year. In total, 195 patients were included. Elevated baseline chromogranin A (CgA), normal creatinine and previous chemotherapy were three risk factors independently associated with 1-year treatment failure. By combining these risk factors, a scoring model was developed which could accurately predict 1-year treatment failure both in the training set (area under curve, AUC, 0.813; 95% CI, 0.731-0.895; P< 0.001) and in the validation set (AUC, 0.816; 95% CI, 0.644-0.968; P< 0.001). After selecting a score of 29.7 as the cut-off value of the scoring model, patients could be stratified into two groups namely low-risk and high-risk with significantly different 1-year treatment failure rate, PFS and overall survival (OS; P< 0.001) both in the training set and validation set. In conclusion, baseline CgA, creatinine level and previous chemotherapy were independently associated with 1-year treatment failure of patients with advanced NET who received 177Lu-Dotatate and the scoring model and prognostic stratification based on these markers could accurately predict 1-year treatment failure, PFS and OS.