Kindts Isabelle, Stellamans Karin, Billiet Ignace, Pottel Hans, Lambrecht Antoon
Department of Radiation Oncology, AZ Groeninge Hospital, President Kennedylaan 4, 8500, Kortrijk, Belgium.
Department of Urology, AZ Groeninge Hospital, Kortrijk, Belgium.
Strahlenther Onkol. 2017 Sep;193(9):707-713. doi: 10.1007/s00066-017-1142-9. Epub 2017 May 9.
To evaluate local recurrence in younger men treated with low-dose-rate (LDR) I brachytherapy (BT) for localized prostate cancer.
A total of 192 patients (≤65-years-old) were treated with LDR I-BT ± hormone therapy. Local failure was defined as any prostate-specific antigen (PSA) rise leading to salvage treatment or biochemical failure according to the Phoenix definition. A bounce was defined as a rise in the nadir of ≥0.2 ng/mL followed by spontaneous return. Proportions were compared using Fisher's exact tests; continuous variables using the unpaired t-test or its non-parametric equivalent. Cox proportional hazards models were applied for multivariable survival analysis.
Median follow-up was 66 months. The 5‑year local recurrence-free survival was 96.1%. Biopsy-proven local recurrence developed in 13 patients, 4 had a Phoenix-defined recurrence at the last follow-up. Androgen deprivation therapy was started in 1 patient without proven recurrence. Univariable risk factors for local recurrence were: at least 50% positive biopsies, intermediate risk, treatment with neoadjuvant hormone therapy, low preimplantation volume receiving 100% of the prescribed dose, and no bounce development. Hormone-naïve patients not attaining a PSA value <0.5 ng/mL during follow-up also had a higher risk of local recurrences. Cox regression demonstrated that the variables "at least 50% positive biopsies" and "bounce" significantly impacted local failure (hazard ratio, HR 1.02 and 11.59, respectively). A bounce developed in 70 patients (36%). Younger patients and those treated with a lower activity per volume had a higher chance of developing a bounce in the Cox model (HR 0.99 and 0.04, respectively).
For younger men, LDR BT is a valid primary curative treatment option in low-risk and is to consider in intermediate-risk localized prostate cancer.
评估低剂量率（LDR）I 近距离放射治疗（BT）用于治疗局限性前列腺癌的年轻男性患者的局部复发情况。
共有192例（年龄≤65岁）患者接受了LDR I-BT ± 激素治疗。局部失败定义为根据Phoenix定义导致挽救性治疗或生化失败的任何前列腺特异性抗原（PSA）升高。反弹定义为最低点升高≥0.2 ng/mL，随后自发恢复。比例采用Fisher精确检验进行比较；连续变量采用非配对t检验或其非参数等价方法。Cox比例风险模型用于多变量生存分析。
中位随访时间为66个月。5年局部无复发生存率为96.1%。13例患者出现活检证实的局部复发，4例在最后一次随访时有Phoenix定义的复发。1例未经证实复发的患者开始接受雄激素剥夺治疗。局部复发的单变量风险因素为：至少50%的活检为阳性、中危、新辅助激素治疗、接受规定剂量100%的植入前低体积、无反弹发生。在随访期间未达到PSA值< 0.5 ng/mL的未接受过激素治疗的患者也有较高的局部复发风险。Cox回归表明，“至少50%的活检为阳性”和“反弹”变量对局部失败有显著影响（风险比分别为1.02和11.59）。70例患者（36%）出现反弹。在Cox模型中，年轻患者和每单位体积接受较低活度治疗的患者出现反弹的可能性更高（风险比分别为0.99和0.04）。
对于年轻男性，LDR BT是低危局限性前列腺癌有效的主要根治性治疗选择，中危局限性前列腺癌也可考虑采用。
