Impact of fluorodeoxyglucose uptake on positron emission tomography/computed tomography on chemosensitivity and survival in patients with metastatic urothelial carcinoma

Objectives: To evaluate the impact of fluorodeoxyglucose uptake on positron emission tomography/computed tomography on chemosensitivity and survival in patients with metastatic urothelial carcinoma. Methods: The present study assessed 51 metastatic urothelial carcinoma patients undergoing fluorodeoxyglucose positron emission tomography/computed tomography before first-line systemic chemotherapy. Fluorodeoxyglucose uptake in metastases was evaluated using the maximum standardized uptake value, which was measured for all eligible lesions, and the highest value among the maximum standardized uptake value measurements in each case was defined as the highest maximum standardized uptake value. The associations between the highest maximum standardized uptake value and objective response rate to chemotherapy, progression-free survival or cancer-specific survival were analyzed. For cancer-specific survival, the C-index was compared between multivariate models that incorporated predictors in the Bajorin model including the Karnofsky performance status and the presence of visceral metastasis, and the Apolo model additionally including hemoglobin and albumin levels, with/without the highest maximum standardized uptake value. Results: The median age was 69 years. The Karnofsky performance status was ≥80% for all patients. Visceral metastasis was observed in 12 patients (24%). The objective response rate, median progression-free survival and median cancer-specific survival were 61%, 9 and 26 months in the entire cohort, respectively. The higher highest maximum standardized uptake value was significantly associated with a lower objective response rate, shorter progression-free survival and shorter cancer-specific survival (P = 0.01, <0.001 and 0.004, respectively). On multivariate analyses, the highest maximum standardized uptake value was an independent predictor for all end-points. In the multivariate models for cancer-specific survival, the C-index improved from 0.559 to 0.601 and from 0.604 to 0.652 by adding the highest maximum standardized uptake value to the parameter set of the Bajorin model and Apolo model, respectively. Conclusions: Higher fluorodeoxyglucose uptake in metastases was significantly and independently associated with poor chemosensitivity and worse survival outcomes. Fluorodeoxyglucose positron emission tomography/computed tomography might aid in patient counseling and treatment decisions for metastatic urothelial carcinoma patients.