Department of Nuclear Medicine, Kanazawa University, Kanazawa, Japan.
Department of Functional Imaging and Artificial Intelligence, Kanazawa University, 13-1 Takara-machi, Kanazawa, 920-8640, Japan.
Ann Nucl Med. 2024 Jun;38(6):428-440. doi: 10.1007/s12149-024-01914-8. Epub 2024 Mar 13.
This study aimed to determine the prognostic value of the flare phenomenon in patients with metastatic castration-resistant prostate cancer (mCRPC) using the bone scan index (BSI) derived from Tc-methylenediphosphonate (MDP) bone scintigraphy images.
We categorized 72 patients from the PROSTAT-BSI registry with mCRPC who were followed-up for 2 years after starting docetaxel chemotherapy to groups based on pre-chemotherapy BSI values of < 1, 1-4, and > 4. We assessed the effects of the flare phenomenon (defined as a > 10% increase in the BSI within 3 months of starting chemotherapy, followed by > 10% improvement within the next 3 months) on survival using Kaplan-Meier curves and Cox proportional hazard analyses.
The flare phenomenon was found in 26 (36%) of the 72 patients. Prostate-specific antigen (PSA), alkaline phosphatase (ALP), and hemoglobin (Hb) levels steadily increased, then deteriorated in patients with and without flare, respectively. Elevated BSI and PSA values at 3 months after starting therapy and the absence of abiraterone or/and enzalutamide therapy led to poor 2-year overall survival (OS) in the group without flare. In contrast, no influence was noticeable in the group with flare. The results of multivariable analyses that included only factors associated with PSA and BSI showed that increased baseline BSI (hazard ratio [HR], 1.39; 95% confidence interval [CI], 1.04-1.86; P = 0.023) and PSA (HR, 7.15; 95% CI 2.13-24.04; P = 0.0015) values could be independent risk factors for patients with mCRPC without flare. However, these factors lost significance during flare. The risk for all-cause death was significantly higher among patients with BSI > 4 without, than with flare. The results of univariable analyses indicated that flare positively impacted survival (HR, 0.24; 95% CI 0.06‒0.91; P = 0.035). Multivariable analysis did not identify any factors that could predict outcomes.
Favorable prognosis, with fewer disturbances from other factors such as the use of abiraterone or/and enzalutamide, PSA changes, and BSI, was attainable in cases when the mCRPC patient demonstrated flare phenomenon. Follow-up bone scintigraphy at least every 3 months could help to determine the prognosis of patients with bone metastasis of mCRPC.
本研究旨在通过 Tc-亚甲基二膦酸盐（MDP）骨闪烁扫描图像的骨扫描指数（BSI），确定转移性去势抵抗性前列腺癌（mCRPC）患者 flare 现象的预后价值。
我们将 PROSTAT-BSI 登记处的 72 名接受多西他赛化疗后随访 2 年的 mCRPC 患者，根据化疗前 BSI 值<1、1-4 和>4 分为三组。我们使用 Kaplan-Meier 曲线和 Cox 比例风险分析评估 flare 现象（定义为化疗开始后 3 个月内 BSI 增加>10%，随后在接下来的 3 个月内增加>10%）对生存的影响。
72 名患者中有 26 名（36%）出现 flare 现象。前列腺特异性抗原（PSA）、碱性磷酸酶（ALP）和血红蛋白（Hb）水平逐渐升高，随后在有和无 flare 的患者中分别恶化。治疗开始后 3 个月时 BSI 和 PSA 值升高且未使用阿比特龙或/和恩扎鲁胺治疗的患者，无 flare 组的 2 年总生存（OS）较差。相比之下，在有 flare 组中未见明显影响。多变量分析仅包括与 PSA 和 BSI 相关的因素，结果表明基线 BSI（危险比[HR]，1.39；95%置信区间[CI]，1.04-1.86；P=0.023）和 PSA（HR，7.15；95%CI，2.13-24.04；P=0.0015）值升高是无 flare 的 mCRPC 患者的独立危险因素。然而，在 flare 期间，这些因素失去了意义。BSI>4 且无 flare 的患者全因死亡风险显著高于有 flare 的患者。单变量分析结果表明，flare 对生存有积极影响（HR，0.24；95%CI，0.06-0.91；P=0.035）。多变量分析未发现任何可预测结局的因素。
在 mCRPC 患者出现 flare 现象时，可获得预后良好的效果，且受 PSA 变化和 BSI 等其他因素的干扰较少，如使用阿比特龙或/和恩扎鲁胺。至少每 3 个月进行一次随访骨闪烁扫描有助于确定 mCRPC 骨转移患者的预后。
