Serum Lactate Dehydrogenase Level Prior to First-Line Chemotherapy for Metastatic Urothelial Carcinoma Is a Prognostic Factor for Avelumab Maintenance Therapy: A Multicenter Retrospective Study.

Objectives: We investigate the association between serum lactate dehydrogenase and prognosis in patients with urothelial carcinoma who were treated with avelumab maintenance therapy in combination with other biomarkers.

Methods: We identified 54 patients with advanced or metastatic urothelial carcinoma that received avelumab maintenance therapy between June 2021 and February 2024 at our institutions. We retrospectively analyzed progression-free survival and overall survival from the initiation of avelumab maintenance therapy. Best overall response was evaluated based on the RECIST guidelines v1.1. To investigate factors potentially associated with response to avelumab maintenance therapy and overall survival, we conducted an assessment of markers that have been previously reported as prognostic factors, including urothelial carcinoma and other cancers.

Results: The median overall survival by best overall response of first-line chemotherapy was not reached for complete response, partial response, or 15-month stable disease (p = 0.27). As for avelumab maintenance therapy, median overall survival by best overall response was not reached for complete response, partial response, and not evaluable; it was 18 months for stable disease and 13 months for progressive disease, with significant differences (p = 0.04). In multivariable analysis, lactate dehydrogenase level below the upper limit of normal prior to first-line chemotherapy was a significant independent factor in predicting disease control rate (p < 0.01) and overall survival (p = 0.04) in avelumab maintenance therapy.

Conclusions: Normal serum lactate dehydrogenase level prior to first-line chemotherapy was a significant predictor of favorable response or prognosis for avelumab maintenance therapy in our cohort.