Hospices Civils de Lyon, Department of Urinary and Vascular Radiology, Hôpital Edouard Herriot, Lyon, France.
BJU Int. 2011 Dec;108(11):1776-81. doi: 10.1111/j.1464-410X.2011.10251.x. Epub 2011 Jun 28.
What's known on the subject ? and What does the study add? Transrectal High-Intensity Focused Ultrasound (HIFU) ablation has been used as a minimally invasive treatment for localized prostate cancer for 15 years. Five-year disease-free survival rates of 66-78% have been reported, challenging the results of external-beam radiation therapy. Usually, a 6-mm safety margin is used in the apex to preserve the urinary sphincter and potency. The influence of this 6-mm margin on the results of the treatment has never been assessed. This retrospective study of a cohort of 99 patients who underwent systematic biopsy 3-6 months after HIFU ablation for prostate cancer (with a 6-mm safety margin in the apex) shows that post-HIFU residual cancer is found more frequently in the apex. Therefore, new strategies improving the prostate destruction at the apex while preserving the urinary continence need to be found.
• To evaluate whether the location (apex/midgland/base) of prostate cancer influences the risk of incomplete transrectal high-intensity focused ultrasonography (HIFU) ablation.
• We retrospectively studied 99 patients who underwent prostate cancer HIFU ablation (Ablatherm; EDAP, Vaulx-en-Velin, France) with a 6-mm safety margin at the apex, and had systematic biopsies 3-6 months after treatment. • Locations of positive pre- and post-HIFU sextants were compared. • The present study included two analyses. First, sextants negative before and positive after treatment were recoded as positive/positive, hypothesizing that cancer had been missed at pretreatment biopsy. Second, patients with such sextants were excluded.
• Pre-HIFU biopsies found cancer in all patients and in 215/594 sextants (36.2%); 55 (25.6%) positive sextants were in the apex, 86 (40%) in the midgland and 74 (34.4%) in the base. • After treatment, residual cancer was found in 36 patients (36.4%) and 50 sextants (8.4%); 30 (60%) positive sextants were in the apex, 12 (24%) in the midgland and eight (16%) in the base. • Both statistical analyses found that the locations of the positive sextants before and after HIFU ablation were significantly different (P < 0.001), with a higher proportion of positive apical sextants after treatment. • At the first analysis, the mean (95% confidence interval) probability for a sextant to remain positive after HIFU ablation was 8.8% (3.5-20.3%) in the base, 12.7% (5.8-25.9%) in the midgland and 41.7% (27.2-57.89%) in the apex. • At the second analysis, these same probabilities were 5.9% (1.9-17%), 9.9% (3.9-23.2%) and 27.3% (13.7-47%), respectively.
• When a 6-mm apical safety margin is used, residual cancer after HIFU ablation is found significantly more frequently in the apex.
评估前列腺癌的位置（尖部/中部/基底部）是否影响经直肠高强度聚焦超声（HIFU）消融治疗不彻底的风险。
我们回顾性研究了 99 例接受前列腺癌 HIFU 消融治疗（Ablatherm；EDAP，Vaulx-en-Velin，法国）的患者，在尖部使用 6mm 的安全边界，并且在治疗后 3-6 个月进行了系统活检。比较了治疗前后阳性六分区的位置。本研究包括两项分析。首先，将治疗前和治疗后均为阳性的六分区重新编码为阳性/阳性，假设在治疗前的活检中遗漏了癌症。其次，排除了这些六分区的患者。
HIFU 治疗前的活检在所有患者和 594 个六分区中的 215 个（36.2%）中发现了癌症；55 个（25.6%）阳性六分区位于尖部，86 个（40%）位于中部，74 个（34.4%）位于基底部。治疗后，36 例（36.4%）和 50 个六分区（8.4%）发现残留癌；30 个（60%）阳性六分区位于尖部，12 个（24%）位于中部，8 个（16%）位于基底部。两种统计学分析均发现 HIFU 消融治疗前后阳性六分区的位置差异有统计学意义（P < 0.001），治疗后尖部阳性六分区的比例更高。在第一次分析中，六分区在 HIFU 消融治疗后仍为阳性的平均（95%置信区间）概率在基底部为 8.8%（3.5-20.3%），在中部为 12.7%（5.8-25.9%），在尖部为 41.7%（27.2-57.89%）。在第二次分析中，这些概率分别为 5.9%（1.9-17%）、9.9%（3.9-23.2%）和 27.3%（13.7-47%）。
当使用 6mm 的尖部安全边界时，HIFU 消融治疗后的残留癌在尖部的检出率显著更高。
