Department of Radiation Oncology, Tata Memorial Hospital, Parel, Mumbai, India.
Department of Radiation Oncology, Tata Memorial Hospital, Parel, Mumbai, India.
Clin Oncol (R Coll Radiol). 2021 Jul;33(7):e315-e321. doi: 10.1016/j.clon.2021.01.009. Epub 2021 Feb 16.
There is a lack of consensus regarding the management of post-chemotherapy residual mass in classical seminoma. The use of fluorodeoxyglucose positron emission tomography-computed tomography (FDG PET-CT) may aid the detection of residual masses harbouring viable disease and help to tailor therapy. The aim of this study was to evaluate if PET-CT could identify patients who will benefit from locoregional radiotherapy.
This ethics-approved study included patients with advanced classical seminoma primarily treated with standard platinum-based first-line chemotherapy. Patients were either observed or given adjuvant radiotherapy based on the clinician's preference and followed up. For this study, patients were stratified into two groups based on FDG PET-CT residual nodal maximum standardised uptake value (SUVmax): low risk (SUVmax <3) and high risk (SUVmax ≥3). Further subgroup analysis was carried out for patients with residual nodal size ≥3 cm and SUVmax ≥3, and this was considered as the very high risk group. The diagnostic accuracy of FDG PET-CT was assessed and survival was compared between the different groups.
Sixty-nine patients were included in the study: 48 patients were observed and 21 received radiotherapy. The low and high risk groups contained 50.7% and 49.3% of the patients, respectively. The very high risk subgroup had 24 patients. At a median follow-up of 44 months, locoregional failures in the radiotherapy and observation cohorts were 0% and 30% (P = 0.059) in the very high risk subgroup and 5.8% and 29.4% (P = 0.078) in the high risk group. The positive predictive value for the very high risk and high risk groups was 30% and 17.1%, respectively. The benefit of locoregional control failed to translate into overall survival benefit.
A tailored, FDG PET-based risk-adapted treatment approach can refine the management of post-chemotherapy residual masses in seminoma. In this study, with the largest cohort of advanced seminoma patients treated with radiotherapy reported to date, radiotherapy seems to benefit patients with post-chemotherapy residual mass SUVmax ≥3.
在经典精原细胞瘤中，对于化疗后残留肿块的处理方法尚未达成共识。氟脱氧葡萄糖正电子发射断层扫描/计算机断层扫描（FDG PET-CT）的应用有助于发现含有存活肿瘤的残留肿块，并有助于制定治疗方案。本研究旨在评估 PET-CT 是否可以识别出将从局部区域放疗中获益的患者。
这项经过伦理批准的研究纳入了主要接受标准铂类一线化疗治疗的晚期经典精原细胞瘤患者。患者根据临床医生的偏好进行观察或辅助放疗，并进行随访。在这项研究中，根据 FDG PET-CT 残留淋巴结最大标准化摄取值（SUVmax），患者分为两组：低危组（SUVmax＜3）和高危组（SUVmax≥3）。对残留淋巴结大小≥3cm 和 SUVmax≥3 的患者进行了进一步的亚组分析，这被认为是极高危组。评估了 FDG PET-CT 的诊断准确性，并比较了不同组之间的生存情况。
研究纳入了 69 例患者：48 例患者接受观察，21 例患者接受放疗。低危组和高危组分别包含了 50.7%和 49.3%的患者。极高危组有 24 例患者。在中位随访 44 个月时，放疗组和观察组在极高危亚组中的局部区域失败率分别为 0%和 30%（P=0.059），在高危组中的局部区域失败率分别为 5.8%和 29.4%（P=0.078）。极高危组和高危组的阳性预测值分别为 30%和 17.1%。局部区域控制的获益未能转化为总体生存获益。
基于 FDG PET 的个体化风险适应治疗方法可以细化精原细胞瘤化疗后残留肿块的管理。在这项研究中，采用了迄今为止报道的最大的接受放疗的晚期精原细胞瘤患者队列，放疗似乎使化疗后残留肿块 SUVmax≥3 的患者受益。
