Bentzen S M, Dische S
Gray Laboratory Cancer Research Trust and The Cancer Centre, Mount Vernon Hospital, Northwood, Middlesex, UK.
Acta Oncol. 2000;39(3):337-47. doi: 10.1080/028418600750013113.
Some of the most debilitating morbidity after surgery and radiotherapy for breast cancer is related to treatment of the axilla. This includes persistent arm lymphoedema, impaired shoulder mobility and brachial plexopathy. Considerable research efforts have been carried out on the radiation pathogenesis and the clinical radiobiology of these clinical endpoints, which has enabled their severity and incidence to be minimized. It is clear that the radiation dose-response relationships for these late endpoints are very steep. In other words, even small changes in the exact dose fractionation and physical dose distribution can cause major changes in toxicity. In particular, in many treatment schedules dose fractions larger than 2 Gy have been used without a sufficient reduction in total dose to avoid increased late effects. This is important, as much of the available literature reports side effects after suboptimal dose-fractionation schedules and inferior radiotherapy techniques. Such reports are not representative of what can be achieved using modern radiotherapy. An interesting parallelism to the problems encountered in reviewing historical experience is found in the British breast litigation, the current status of which is presented in this article. Furthermore, morbidity after radiotherapy is strongly influenced by concomitant surgery and/or chemotherapy, and this should be allowed for when designing the overall treatment. Apart from other therapeutic modalities, it has been suggested that other exogenous factors have an influence on the risk of radiotherapy-related morbidity. However, patients' age and, in the case of lymphoedema, also obesity are the only factors that have been established with some certainty. Routine adjustment of radiotherapy dose in these cases is not recommended. Two current developments may strengthen the role of radiotherapy in the treatment of breast cancer. Sentinel node biopsy may allow nodal staging without major surgical excision of axillary nodes and this opens the possibility for a more optimal combination of radiotherapy and surgery in the management of the axilla. With more cancers now being detected by systematic screening programmes, this will also increase the possibilities for conservative management, which in most cases involves radiotherapy. In conclusion, the improved understanding of the clinical radiobiology of late sequelae after radiotherapy allows treatment schedules and techniques to be devised that are therapeutically effective while maintaining a minimal risk of serious, late morbidity.
乳腺癌手术和放疗后一些最使人衰弱的发病情况与腋窝治疗有关。这包括持续性手臂淋巴水肿、肩部活动受限和臂丛神经病变。针对这些临床终点的放射发病机制和临床放射生物学已经开展了大量研究工作，从而使它们的严重程度和发生率得以降至最低。很明显，这些晚期终点的放射剂量反应关系非常陡峭。换句话说，即使精确的剂量分割和物理剂量分布有很小的变化，也可能导致毒性发生重大变化。特别是，在许多治疗方案中，使用了大于2 Gy的剂量分割，而总剂量却没有充分降低以避免后期效应增加。这一点很重要，因为现有许多文献报道的是次优剂量分割方案和较差放疗技术后的副作用。此类报道并不代表现代放疗所能达到的效果。在回顾历史经验时遇到的问题，在英国乳腺癌诉讼中有一个有趣的相似情况，本文介绍了其现状。此外，放疗后的发病情况还受到同期手术和/或化疗的强烈影响，在设计整体治疗方案时应予以考虑。除其他治疗方式外，有人提出其他外部因素也会影响放疗相关发病风险。然而，患者年龄以及在淋巴水肿情况下的肥胖，是仅有的一些已确定有一定关联的因素。不建议在这些情况下常规调整放疗剂量。目前的两项进展可能会加强放疗在乳腺癌治疗中的作用。前哨淋巴结活检可在不进行腋窝淋巴结大手术切除的情况下进行淋巴结分期，这为腋窝管理中放疗和手术的更优化组合开辟了可能性。随着现在通过系统筛查计划发现更多癌症，这也将增加保守治疗的可能性，而保守治疗在大多数情况下都涉及放疗。总之，对放疗后晚期后遗症临床放射生物学的更好理解，有助于设计出治疗有效的治疗方案和技术，同时将严重晚期发病的风险降至最低。
