Stromberg J, Martinez A, Gonzalez J, Edmundson G, Ohanian N, Vicini F, Hollander J, Gustafson G, Spencer W, Yan D i
Department of Radiation Oncology, William Beaumont Hospital, Royal Oak, MI 48073, USA.
Int J Radiat Oncol Biol Phys. 1995 Aug 30;33(1):161-71. doi: 10.1016/0360-3016(95)00035-w.
To improve results for locally advanced prostate cancer, a prospective clinical trial of concurrent external beam irradiation and fractionated iridium-192 (Ir-192) high dose rate (HDR) conformal boost brachytherapy was initiated.
Between November 1991 and February 1994, 99 implants were performed on 33 patients with prostatic adenocarcinoma at William Beaumont Hospital. Using AJCC staging criteria, 9 patients had T2b tumors, 17 patients had T2c tumors, and 7 patients had T3 disease. Patients were treated with (a) 45.6 Gy whole pelvis external irradiation and (b) three HDR fractions of 5.5 Gy each (18 patients) or 6 Gy each (15 patients) to the prostate. Transperineal needle implants using real-time ultrasound guidance with interactive on-line isodose distributions were performed on an outpatient basis during weeks 1, 2, and 3 of external irradiation. Acute toxicity was scored using the Radiation Therapy Oncology Group (RTOG) morbidity grading system.
This technique of concurrent external pelvic irradiation and conformal HDR brachytherapy was well tolerated. No significant intraoperative or perioperative complications occurred. Three patients (9%) experienced Grade 3 acute toxicity (two dysuria and one diarrhea). All toxicities were otherwise Grades 1 or 2 and were primarily as expected from pelvic external irradiation. Persistent implant-related toxicities included Grades 1-2 perineal pain (12%) and hematospermia (15%). Median follow-up time was 13 months. Serum prostatic-specific antigen (PSA) levels normalized in 91% of patients (29 out of 32) within 1-14 months (median 2.8 months) after irradiation. PSA levels were progressively decreasing in the other three patients at last measurement. Prospectively planned prostatic rebiopsies done at 18 months in the first 10 patients were negative in 9 out of 10 (90%).
Acute toxicity has been acceptable with this unique approach using conformal high dose rate Ir-192 boost brachytherapy with concurrent external irradiation. The initial tumor response as assessed by serial PSA measurement and rebiopsy is extremely encouraging. Dose escalation will proceed in accordance with the protocol guidelines. Further patient accrual and longer follow-up will allow comparison to other techniques.
为提高局部晚期前列腺癌的治疗效果，开展了一项同步外照射与分次铱 - 192（Ir - 192）高剂量率（HDR）适形增敏近距离放射治疗的前瞻性临床试验。
1991年11月至1994年2月期间，在威廉·博蒙特医院对33例前列腺腺癌患者进行了99次植入治疗。根据美国癌症联合委员会（AJCC）分期标准，9例患者为T2b期肿瘤，17例患者为T2c期肿瘤，7例患者为T3期疾病。患者接受（a）45.6 Gy的全盆腔外照射，以及（b）对前列腺进行三次HDR分次照射，每次剂量分别为5.5 Gy（18例患者）或6 Gy（15例患者）。在体外照射的第1、2和3周，在门诊通过实时超声引导并结合在线等剂量分布进行经会阴针植入。使用放射治疗肿瘤学组（RTOG）发病率分级系统对急性毒性进行评分。
这种同步盆腔外照射与适形HDR近距离放射治疗技术耐受性良好。未发生明显的术中或围手术期并发症。3例患者（9%）出现3级急性毒性反应（2例尿痛和1例腹泻）。其他所有毒性反应均为1级或2级，主要与盆腔外照射预期的情况相符。与植入相关的持续性毒性反应包括1 - 2级会阴部疼痛（12%）和血精（15%）。中位随访时间为13个月。91%的患者（32例中的29例）在照射后1 - 14个月（中位时间2.8个月）内血清前列腺特异性抗原（PSA）水平恢复正常。在最后一次测量时，其他3例患者的PSA水平逐渐下降。对前10例患者在18个月时进行的前瞻性计划前列腺再次活检中，10例中有9例（90%）结果为阴性。
采用适形高剂量率Ir - 192增敏近距离放射治疗与同步外照射的这种独特方法，急性毒性反应是可接受的。通过连续PSA测量和再次活检评估的初始肿瘤反应非常令人鼓舞。将根据方案指南进行剂量递增。进一步纳入患者并延长随访时间将有助于与其他技术进行比较。
