Gheorghiu Monica Livia
C.I. Parhon" National Institute of Endocrinology, "Carol Davila" University of Medicine and Pharmacy, Bucharest, Romania.
Pituitary. 2017 Feb;20(1):154-168. doi: 10.1007/s11102-016-0783-5.
Purpose Treatment of acromegaly has undergone important progress in the last 20 years mainly due to the development of new medical options and advances in surgical techniques. Pituitary surgery is usually first-line therapy, and medical treatment is indicated for persistent disease, while radiation (RT) is often used as third-line therapy. The benefits of RT (tumor volume control and decreased hormonal secretion) are hampered by the long latency of the effect and the high risk of adverse effects. Stereotactic RT methods have been developed with the aim to provide more precise targeting of the tumor with better control of the radiation dose received by the adjacent brain structures. The purpose of this review is to present the updates in the efficacy and safety of pituitary RT in acromegalic patients, with an emphasis on the new stereotactic radiation techniques. Methods A systematic review was performed using PubMed and articles/abstracts and reviews detailing RT in acromegaly from 2000 to 2016 were included. Results Stereotactic radiosurgery and fractionated stereotactic RT (FSRT) for patients with persistent active acromegaly after surgery and/or during medical therapy provide comparable high rates of tumor control, i.e. stable or decrease in size of the tumor in 93-100% of patients at 5-10 years and endocrinological remission in 40-60% of patients at 5 years. Hypofractionated RT is an optimal option for tumors located near the optic structures, due to its lower toxicity for the optic nerves compared to single-dose radiosurgery. The rate of new hypopituitarism varies from 10 to 50% at 5 years and increases with the duration of follow-up. The risk for other radiation-induced complications is usually low (0-5% for new visual deficits, cranial nerves damage or brain radionecrosis and 0-1% for secondary brain tumors) and risk of stroke may be higher in FSRT. Conclusion Although the use of radiotherapy in patients with acromegaly has decreased with advances in medical treatments, it remains an effective treatment option after unsuccessful surgery and/or resistance or unavailability of medical therapy. Long-term studies evaluating secondary morbidity and mortality rate after the new stereotactic techniques are needed, in order to evaluate their potential brain-sparing effect.
目的 在过去20年中，肢端肥大症的治疗取得了重要进展，这主要归功于新的药物治疗方法的发展和手术技术的进步。垂体手术通常是一线治疗方法，药物治疗适用于持续性疾病，而放射治疗（RT）通常用作三线治疗。RT的益处（肿瘤体积控制和激素分泌减少）受到疗效延迟长和不良反应风险高的阻碍。立体定向RT方法的开发旨在更精确地靶向肿瘤，同时更好地控制邻近脑结构所接受的辐射剂量。本综述的目的是介绍垂体RT在肢端肥大症患者中的疗效和安全性的最新进展，重点是新的立体定向放射技术。方法 使用PubMed进行系统综述，纳入2000年至2016年详细介绍肢端肥大症RT的文章/摘要和综述。结果 对于手术后和/或药物治疗期间持续存在活动性肢端肥大症的患者，立体定向放射外科手术和分次立体定向RT（FSRT）可提供相当高的肿瘤控制率，即在5至10年时，93%至100%的患者肿瘤稳定或缩小，在5年时，40%至60%的患者内分泌缓解。与单剂量放射外科手术相比，低分次RT对位于视神经结构附近的肿瘤是一种最佳选择，因为它对视神经的毒性较低。5年时新发生垂体功能减退的发生率在10%至50%之间，并随随访时间的延长而增加。其他辐射诱导并发症的风险通常较低（新的视力缺陷、颅神经损伤或脑放射性坏死为0%至5%，继发性脑肿瘤为0%至1%），FSRT中中风的风险可能更高。结论 尽管随着药物治疗的进展，肢端肥大症患者放射治疗的使用有所减少，但在手术失败和/或药物治疗耐药或无法使用后，它仍然是一种有效的治疗选择。需要进行长期研究来评估新的立体定向技术后的继发性发病率和死亡率，以评估它们潜在的脑保护作用。
