Hayman Jonathan, Phillips Ryan, Chen Di, Perin Jamie, Narang Amol K, Trieu Janson, Radwan Noura, Greco Stephen, Deville Curtiland, McNutt Todd, Song Daniel Y, DeWeese Theodore L, Tran Phuoc T
Department of Internal Medicine, Johns Hopkins Bayview Hospital, Baltimore, Maryland.
Department of Radiation Oncology and Molecular Radiation Sciences, Johns Hopkins Hospital, Baltimore, Maryland.
Prostate. 2018 Jun;78(8):623-630. doi: 10.1002/pros.23507. Epub 2018 Mar 9.
Undetectable End of Radiation PSA (EOR-PSA) has been shown to predict improved survival in prostate cancer (PCa). While validating the unfavorable intermediate-risk (UIR) and favorable intermediate-risk (FIR) stratifications among Johns Hopkins PCa patients treated with radiotherapy, we examined whether EOR-PSA could further risk stratify UIR men for survival.
A total of 302 IR patients were identified in the Johns Hopkins PCa database (178 UIR, 124 FIR). Kaplan-Meier curves and multivariable analysis was performed via Cox regression for biochemical recurrence free survival (bRFS), distant metastasis free survival (DMFS), and overall survival (OS), while a competing risks model was used for PCa specific survival (PCSS). Among the 235 patients with known EOR-PSA values, we then stratified by EOR-PSA and performed the aforementioned analysis.
The median follow-up time was 11.5 years (138 months). UIR was predictive of worse DMFS and PCSS (P = 0.008 and P = 0.023) on multivariable analysis (MVA). Increased radiation dose was significant for improved DMFS (P = 0.016) on MVA. EOR-PSA was excluded from the models because it did not trend towards significance as a continuous or binary variable due to interaction with UIR, and we were unable to converge a multivariable model with a variable to control for this interaction. However, when stratifying by detectable versus undetectable EOR-PSA, UIR had worse DMFS and PCSS among detectable EOR-PSA patients, but not undetectable patients. UIR was significant on MVA among detectable EOR-PSA patients for DMFS (P = 0.021) and PCSS (P = 0.033), while RT dose also predicted PCSS (P = 0.013).
EOR-PSA can assist in predicting DMFS and PCSS among UIR patients, suggesting a clinically meaningful time point for considering intensification of treatment in clinical trials of intermediate-risk men.
放射治疗后前列腺特异性抗原（PSA）不可检测的放疗结束时PSA（EOR-PSA）已被证明可预测前列腺癌（PCa）患者生存率的提高。在对接受放疗的约翰霍普金斯医院PCa患者中的不良中危（UIR）和良好中危（FIR）分层进行验证时，我们研究了EOR-PSA是否能进一步对UIR男性患者的生存风险进行分层。
在约翰霍普金斯医院PCa数据库中识别出302例中危患者（178例UIR，124例FIR）。通过Cox回归对生化无复发生存期（bRFS）、无远处转移生存期（DMFS）和总生存期（OS）进行Kaplan-Meier曲线分析和多变量分析，同时使用竞争风险模型分析前列腺癌特异性生存期（PCSS）。在235例已知EOR-PSA值的患者中，我们随后根据EOR-PSA进行分层并进行上述分析。
中位随访时间为11.5年（138个月）。多变量分析（MVA）显示，UIR预示着更差的DMFS和PCSS（P = 0.008和P = 0.023）。多变量分析显示，增加放疗剂量对改善DMFS具有显著意义（P = 0.016）。EOR-PSA被排除在模型之外，因为由于与UIR的相互作用，它作为连续变量或二元变量均未呈现出显著趋势，并且我们无法构建一个包含控制这种相互作用变量的多变量模型。然而，当按可检测与不可检测的EOR-PSA进行分层时，在可检测EOR-PSA的患者中，UIR的DMFS和PCSS更差，但在不可检测的患者中并非如此。在可检测EOR-PSA的患者中，多变量分析显示UIR对DMFS（P = 0.021）和PCSS（P = 0.033）具有显著意义，而放疗剂量也可预测PCSS（P = 0.013）。
EOR-PSA有助于预测UIR患者的DMFS和PCSS，这表明在中危男性患者的临床试验中，它是考虑强化治疗的一个具有临床意义的时间点。
