Size of pelvic bone metastasis as a significant prognostic factor for metastatic prostate cancer patients

Introduction To investigate the potential prognostic value of image analysis of pelvic bone metastasis in newly diagnosed prostate cancer patients. Methods Data from 69 patients with both bone scintigraphy and pelvic CT images were selected for this analysis. Open source software (3D Slicer version 4.8.1.) was used for image analysis. Metastatic pelvic bone lesions were manually contoured, and radiomic features were extracted. As risk factors for overall survival (OS) and cause-specific survival (CSS), 105 radiomic features and clinical risk factors including age, initial prostate-specific antigen, Gleason score, TNM stage, lactate dehydrogenase (LDH), hemoglobin (Hb), alkaline phosphatase, extent of disease, visceral metastases, and radiotherapy were assessed by uni- and multivariate analyses. Results Median follow-up was 41 months (range 0-157 months). Five-year overall survival and cause-specific survival rate were 37.9% and 43.5%, respectively. After multivariate analysis, LDH, Hb, and maximum 2D diameter defined as maximum tumor size in the axial plane were detected as risk factors for OS. Gleason sum, LDH, and maximum 2D diameter were detected as risk factors for CSS. Conclusion Maximum 2D diameter was detected as a significant prognostic factor for metastatic prostate cancer patients.