Cellini Numa, Morganti Alessio G, Mattiucci Gian C, Valentini Vincenzo, Leone Mariavittoria, Luzi Stefano, Manfredi Riccardo, Dinapoli Nicola, Digesu' Cinzia, Smaniotto Daniela
Division of Radiotherapy, Catholic University of the Sacred Heart, Policlinico A. Gemelli, Largo A. Gemelli 8, 00168 Rome, Italy.
Int J Radiat Oncol Biol Phys. 2002 Jul 1;53(3):595-9. doi: 10.1016/s0360-3016(02)02795-5.
Conformal therapy of prostate cancer is based on high-dose irradiation to the entire prostate gland. The aim of this study was to analyze the pattern of intraprostatic recurrence in patients undergoing external beam radiotherapy (EBRT) at a dose of 65-70 Gy to evaluate whether conventional radiotherapy doses are adequate to control microscopic disease outside the primary tumor and therefore whether high-dose irradiation can be exclusively focused on the macroscopic disease.
The clinical and radiologic reports of 118 patients with prostate cancer undergoing EBRT (64.8-70.2 Gy) combined with hormonal therapy were evaluated. In all patients, before and after therapy, the size and site of the primary neoplasm within the prostate were assessed by clinical examination and imaging studies.
With a median follow-up of 45 months (range 14-119), the 5-year actuarial local control rate was 83.9%. Twelve patients had an intraprostatic recurrence, with the appearance of a new nodule (in 5 patients with a complete response after therapy) or increased nodular size compared with the minimal size (in the 7 other patients). In all patients, on the basis of a semiquantitative evaluation of the site of recurrence, this was shown to originate within the initial tumor volume.
The results of this analysis seem to confirm some histologic findings observed in patients undergoing prostatectomy for local recurrence after radiotherapy that suggest that local recurrence usually originates in the primary tumor rather than in focal prostatic intraepithelial neoplasia. This observation might justify the application of conformal therapy procedures aimed at identifying the gross tumor volume, in the phase of boost, exclusively with the primary tumor.
前列腺癌的适形治疗基于对整个前列腺腺体进行高剂量照射。本研究的目的是分析接受65 - 70 Gy外照射放疗（EBRT）的患者前列腺内复发模式，以评估传统放疗剂量是否足以控制原发肿瘤外的微小病灶，从而判断高剂量照射是否可仅聚焦于宏观病灶。
对118例接受EBRT（64.8 - 70.2 Gy）联合激素治疗的前列腺癌患者的临床和放射学报告进行评估。所有患者在治疗前后均通过临床检查和影像学研究评估前列腺内原发肿瘤的大小和部位。
中位随访45个月（范围14 - 119个月），5年精算局部控制率为83.9%。12例患者出现前列腺内复发，表现为出现新结节（5例治疗后完全缓解患者）或与最小尺寸相比结节增大（其他7例患者）。所有患者中，根据复发部位的半定量评估，显示复发起源于初始肿瘤体积内。
该分析结果似乎证实了在接受放疗后因局部复发而行前列腺切除术的患者中观察到的一些组织学发现，即局部复发通常起源于原发肿瘤而非局灶性前列腺上皮内瘤变。这一观察结果可能证明在增强放疗阶段仅针对原发肿瘤识别大体肿瘤体积的适形治疗程序的应用是合理的。
