Skowrońska-Gardas Anna, Chojnacka Marzanna, Morawska-Kaczyńska Marzena, Perek Danuta, Perek-Polnik Marta
Department of Radiotherapy, M.Skłodowska-Curie Memorial Cancer Centre - Institute, Warsaw, Poland.
Radiother Oncol. 2007 Jul;84(1):26-33. doi: 10.1016/j.radonc.2007.05.018. Epub 2007 Jun 8.
Craniospinal irradiation for medulloblastoma is one of the most complex techniques employed in radiotherapy. Many reports stress the impact of irradiation quality on survival in these patients. Our report presents the outcome and patterns of failure for 95 patients treated with 3D conformal radiotherapy (3D-CRT).
From 1998 to 2003, 95 children with medulloblastoma received 3D conformal radiotherapy. All of them were previously treated with surgery and chemotherapy. The brain and upper spinal cord were treated with two lateral 6MV photon fields. In four patients, the cribriform plate was irradiated by the additional field. For primary tumour bed we applied two or three photon beams. Spinal cord was irradiated either with 18-20MeV electron fields or with a mixed beam.
With a median follow-up of 48 months, 32/95 patients suffered a multifocal (21) or isolated (11) recurrence. We evaluated every primary site of failure. In all patients, the recurrence appeared within the isodose level of 95-100%.
Patterns of failure in medulloblastoma patients treated with 3D conformal radiotherapy indicated that the relapse was mainly associated with poor response to pre-irradiation chemotherapy. We believe that 3D conformal radiotherapy allows avoiding failures, related to radiotherapy uncertainties.
髓母细胞瘤的颅脊髓照射是放射治疗中最复杂的技术之一。许多报告强调了照射质量对这些患者生存的影响。我们的报告呈现了95例接受三维适形放疗（3D-CRT）患者的治疗结果及失败模式。
1998年至2003年，95例髓母细胞瘤患儿接受了三维适形放疗。他们均曾接受手术和化疗。大脑和上脊髓采用两个侧方6MV光子野照射。4例患者的筛板通过附加野照射。对于原发肿瘤床，我们应用两束或三束光子束。脊髓采用18 - 20MeV电子野或混合束照射。
中位随访48个月，95例患者中有32例发生多灶性（21例）或孤立性（11例）复发。我们评估了每个原发失败部位。所有患者的复发均出现在95% - 100%等剂量线范围内。
三维适形放疗治疗的髓母细胞瘤患者的失败模式表明，复发主要与放疗前化疗反应不佳有关。我们认为三维适形放疗能够避免与放疗不确定性相关的失败。
