Gheorghiu M L, Fleseriu M
"Carol Davila" University of Medicine and Pharmacy, "C.I. Parhon" National Institute of Endocrinology, Bucharest, Romania.
Oregon Health & Science University, Departments of Medicine (Endocrinology) and Neurological Surgery, and Northwest Pituitary Center, Portland, USA.
Acta Endocrinol (Buchar). 2017 Oct-Dec;13(4):476-490. doi: 10.4183/aeb.2017.476.
Pituitary radiotherapy (RT) has undergone important progress in the last decades due to the development of new stereotactic techniques which provide more precise tumour targeting with less overall radiation received by the adjacent brain structures. Pituitary surgery is usually first-line therapy in most patients with nonfunctioning (NFPA) and functioning adenomas (except for prolactinomas and large growth hormone (GH) secreting adenomas), while RT is used as second or third-line therapy. The benefits of RT (tumour volume control and, in functional tumours, decreased hormonal secretion) are hampered by the long latency of the effect and the potential side effects. This review presents the updates in the efficacy and safety of the new stereotactic radiation techniques in patients with NFPA, GH-, ACTH- or PRL-secreting pituitary adenomas.
A systematic review was performed using PubMed and articles/abstracts and reviews detailing RT in pituitary adenomas from 2000 to 2017 were included.
Stereotactic radiosurgery (SRS) and fractionated stereotactic RT (FSRT) provide high rates of tumour control i.e. stable or decrease in tumour size, in all types of pituitary adenomas (median 92 - 98%) at 5 years. Endocrinological remission is however significantly lower: 44-52% in acromegaly, 54-64% in Cushing's disease and around 30% in prolactinomas at 5 years. The rate of new hypopituitarism varies from 10% to 50% at 5 years in all tumour types and as expected increases with the duration of follow-up (FU). The risk for other radiation-induced complications is usually low (0-5% for new visual deficits, cranial nerves damage or brain radionecrosis and extremely low for secondary brain tumours), however longer FU is needed to determine rates of secondary tumours. Notably, in acromegaly, there may be a higher risk for stroke with FSRT.
Stereotactic radiotherapy can be an effective treatment option for patients with persistent or recurrent pituitary adenomas after unsuccessful surgery (especially if residual tumour is enlarging) and/or resistance or unavailability of medical therapy. Comparison with conventional radiation therapy (CRT) is rather difficult, due to the substantial heterogeneity of the studies. In order to evaluate the potential brain-sparing effect of the new stereotactic techniques, suggested by the current data, long-term studies evaluating secondary morbidity and mortality are needed.
在过去几十年中，由于新的立体定向技术的发展，垂体放射治疗（RT）取得了重要进展，这些技术能更精确地靶向肿瘤，同时减少邻近脑结构所接受的总体辐射量。垂体手术通常是大多数无功能腺瘤（NFPA）和功能性腺瘤（催乳素瘤和大型生长激素（GH）分泌腺瘤除外）患者的一线治疗方法，而RT用作二线或三线治疗。RT的益处（肿瘤体积控制以及在功能性肿瘤中激素分泌减少）受到疗效延迟和潜在副作用的阻碍。本综述介绍了新的立体定向放射技术在NFPA、GH、促肾上腺皮质激素（ACTH）或催乳素（PRL）分泌型垂体腺瘤患者中的疗效和安全性的最新情况。
使用PubMed进行系统综述，并纳入2000年至2017年详细介绍垂体腺瘤RT的文章/摘要和综述。
立体定向放射外科（SRS）和分次立体定向RT（FSRT）在5年时对所有类型的垂体腺瘤都能提供较高的肿瘤控制率，即肿瘤大小稳定或缩小（中位数为92%-98%）。然而，内分泌缓解率显著较低：肢端肥大症患者5年时为44%-52%，库欣病患者为54%-64%，催乳素瘤患者约为30%。所有肿瘤类型在5年时新发生垂体功能减退的发生率在10%至50%之间，并且正如预期的那样，随着随访时间（FU）的延长而增加。其他辐射诱发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的发生率为0%-5%，继发性脑肿瘤的发生率极低），然而需要更长的FU时间来确定继发性肿瘤的发生率。值得注意的是，在肢端肥大症患者中，FSRT导致中风的风险可能更高。
对于手术失败后（特别是残留肿瘤增大时）和/或药物治疗耐药或无法使用的持续性或复发性垂体腺瘤患者，立体定向放射治疗可以是一种有效的治疗选择。由于研究的实质性异质性，与传统放射治疗（CRT）进行比较相当困难。为了评估当前数据所提示的新立体定向技术潜在的脑保护作用，需要进行评估继发性发病率和死亡率的长期研究。
