Department of Radiation Oncology, University of Virginia, Charlottesville, VA, USA.
Department of Neurosurgery, University of Virginia, Charlottesville, VA, USA.
J Neurooncol. 2019 Nov;145(2):301-307. doi: 10.1007/s11060-019-03296-8. Epub 2019 Sep 20.
Surgical resection is the first line treatment for growth hormone (GH) secreting tumors. Stereotactic radiosurgery (SRS) is recommended for patients who do not achieve endocrine remission after resection. The purpose of this study was to evaluate safety and efficacy of repeat radiosurgery for acromegaly.
Three hundred and ninety-eight patients with acromegaly treated with the Gamma Knife radiosurgery (Elekta AB, Stockholm) were identified from the International Gamma Knife Research Foundation database. Among these, 21 patients underwent repeated SRS with sufficient endocrine follow-up and 18 patients had sufficient imaging follow-up. Tumor control was defined as lack of adenoma progression on imaging. Endocrine remission was defined as a normal IGF-1 concentration while off medical therapy.
Median time from initial SRS to repeat SRS was 5.0 years. The median imaging and endocrine follow-up duration after repeat SRS was 3.4 and 3.8 years, respectively. The median initial marginal dose was 17 Gy, and the median repeat marginal dose was 23 Gy. Of the 18 patients with adequate imaging follow up, 15 (83.3%) patients had tumor control and of 21 patients with endocrine follow-up, 9 (42.9%) patients had endocrine remission at last follow-up visit. Four patients (19.0%) developed new deficits after repeat radiosurgery. Of these, 3 patients had neurologic deficits and 1 patient had endocrine deficit.
Repeat radiosurgery for persistent acromegaly offers a reasonable benefit to risk profile for this challenging patient cohort. Further studies are needed to identify patients best suited for this type of approach.
手术切除是生长激素（GH）分泌肿瘤的一线治疗方法。对于切除后未达到内分泌缓解的患者，推荐进行立体定向放射外科手术（SRS）。本研究旨在评估重复放射外科手术治疗肢端肥大症的安全性和疗效。
从国际伽玛刀研究基金会数据库中确定了 398 例接受伽玛刀放射外科治疗的肢端肥大症患者。其中，21 例患者在有足够内分泌随访的情况下接受了重复 SRS，18 例患者有足够的影像学随访。肿瘤控制定义为影像学上无腺瘤进展。内分泌缓解定义为在停止药物治疗时 IGF-1 浓度正常。
从初次 SRS 到重复 SRS 的中位时间为 5.0 年。重复 SRS 后中位影像学和内分泌随访时间分别为 3.4 年和 3.8 年。初次边缘剂量的中位数为 17 Gy，重复边缘剂量的中位数为 23 Gy。在 18 例有足够影像学随访的患者中，15 例（83.3%）患者肿瘤得到控制，在 21 例有内分泌随访的患者中，9 例（42.9%）患者在最后一次随访时内分泌缓解。4 例（19.0%）患者在重复放射外科手术后出现新的缺陷。其中，3 例有神经功能缺损，1 例有内分泌功能缺损。
对于持续性肢端肥大症患者，重复放射外科手术是一种具有合理风险效益比的治疗方法。需要进一步的研究来确定最适合这种治疗方法的患者群体。
