Department of Nuclear Medicine and PET, Royal Marsden Hospital, Downs Rd, Sutton, Surrey, SM2 5PT, UK.
Eur J Nucl Med Mol Imaging. 2011 Jan;38(1):7-13. doi: 10.1007/s00259-010-1576-0. Epub 2010 Aug 10.
Bone scintigraphy (BS) lacks sensitivity for detecting very early skeletal metastases (SM) in prostate cancer (PC) and is often limited by poor specificity. Also scintigraphic flare of SM can occur following effective treatment and mislead an early response assessment. We hypothesised that a flare reaction might amplify the signal from subclinical SM, increasing the sensitivity of BS and that the phenomenon may be specific for metastases.
We conducted a prospective study to determine the frequency of the flare phenomenon in patients with metastatic PC starting hormone therapy and to explore its utility in patients with negative staging scans but considered at high risk of SM and in those with equivocal baseline BS abnormalities. Ninety-nine patients commencing first-line hormone therapy had repeat BS at 6 weeks to score a flare reaction.
Of 22 patients with unequivocal SM on the baseline scan, a flare occurred in 9 (41%). Of 36 high-risk localised prostate cancer patients with normal BS pre-treatment, the scan became positive for metastases at 6 weeks in 4 (11%). Of 41 patients with pre-treatment scintigraphic abnormalities of uncertain aetiology, a flare occurred in 8 cases (20%). All eight were confirmed to have SM by follow-up and imaging. Of the 33 remaining patients without a flare, 2 developed SM at 14 months and the remainder did not develop SM in a median follow-up period of 36 months.
The flare phenomenon following initial hormone therapy can be used to improve both sensitivity and specificity of BS in PC.
骨闪烁扫描（BS）在检测前列腺癌（PC）的早期骨转移（SM）时缺乏敏感性，并且通常受到特异性差的限制。此外，SM 的闪烁反应可能在有效治疗后发生，并导致早期反应评估出现偏差。我们假设， flares 反应可能会放大来自亚临床 SM 的信号，从而提高 BS 的敏感性，并且这种现象可能是转移性疾病的特异性。
我们进行了一项前瞻性研究，以确定开始激素治疗的转移性 PC 患者 flare 现象的频率，并探讨其在分期扫描阴性但被认为具有高转移风险的患者以及基线 BS 异常的患者中的应用价值。99 例开始一线激素治疗的患者在 6 周时进行重复 BS 以评分 flare 反应。
在基线扫描中明确存在 SM 的 22 例患者中，有 9 例（41%）出现 flare 反应。在 36 例治疗前 BS 正常的局部前列腺癌高危患者中，有 4 例（11%）在 6 周时扫描结果显示转移。在 41 例治疗前 BS 异常原因不明的患者中，有 8 例出现 flare 反应（20%）。所有 8 例均通过随访和影像学检查证实存在 SM。在 33 例无 flare 反应的患者中，有 2 例在 14 个月时发展为 SM，其余患者在中位随访 36 个月期间未发展为 SM。
初始激素治疗后出现 flares 现象可提高 BS 在 PC 中的敏感性和特异性。
