Department of Radiation Oncology, Peter MacCallum Cancer Centre, Melbourne, Australia; The Sir Peter MacCallum Department of Oncology, University of Melbourne, Melbourne, Australia.
The Sir Peter MacCallum Department of Oncology, University of Melbourne, Melbourne, Australia; Department of Molecular Imaging, Peter MacCallum Cancer Centre, Melbourne, Australia.
Int J Radiat Oncol Biol Phys. 2020 Sep 1;108(1):204-211. doi: 10.1016/j.ijrobp.2020.02.636. Epub 2020 Mar 7.
Patients with abscopal regressions of lymphoma after palliative involved-site radiation therapy (ISRT), detected on sequential F-fluorodeoxyglucose positron emission tomography (FDG-PET), were identified by audit. A retrospective analysis was subsequently conducted to estimate the frequency of abscopal regression in follicular lymphoma (FL).
Potential cases were identified at multidisciplinary lymphoma meetings and fulfilled these criteria: (1) palliative ISRT given for histologically confirmed lymphoma, (2) >2 lesions visualized on FDG-PET, (3) >1 unirradiated lesion(s) outside ISRT volume, (4) no systemic therapy delivered <2 months before radiation therapy or between radiation therapy and response assessment, (5) complete metabolic response (CMR) in ≥1 unirradiated lesions detected on serial FDG-PET/CT. All ISRT patients with FL treated in 2016 to 2018 were systematically reviewed.
Seven cases of abscopal regression were identified, including 4 patients with FL. In all cases, a CMR was apparent both within the ISRT volume and in ≥1 unirradiated lesions. One patient each was identified with mantle cell lymphoma (4 Gy in 2 fractions), Hodgkin lymphoma (20 Gy in 3 fractions, then 30 Gy in 15 fractions to the same volume), and Richter transformation of chronic lymphatic leukemia (30 Gy in 10 fractions). The 4 patients with FL received either 4 Gy in 2 fractions (n = 3) or 4 Gy followed 8 months later by 30 Gy in 15 fractions (n = 1). From 2016 to 2018, 29 courses of ISRT were prescribed for multifocal FL, after which 4 of 29 (13.8%) abscopal responses were detected, including in 4 of 9 (44.4%) patients with serial PET scans. Two patients, with relapsed disease after initial abscopal responses, experienced durable CMRs with immunotherapies.
In 4 of 7 cases, PET-detected abscopal regression of lymphoma occurred after 4 Gy, in 2 of 7 cases after repeated ISRT to the same volume, and in 2 of 7 was associated with subsequent complete response to immunotherapy, consistent with an immune basis for the abscopal effect. Abscopal regressions in FL appear to be more common than previously suspected.
通过审核，确定了姑息性累及部位放射治疗（ISRT）后淋巴瘤患者的远处退缩反应，这些患者在连续氟-18 氟代脱氧葡萄糖正电子发射断层扫描（FDG-PET）上得到了检测。随后进行了回顾性分析，以估计滤泡性淋巴瘤（FL）中远处退缩反应的频率。
在多学科淋巴瘤会议上确定了潜在病例，并符合以下标准：（1）因组织学证实的淋巴瘤给予姑息性 ISRT；（2）FDG-PET 上可见>2 处病变；（3）ISRT 体积外有>1 处未照射的病变；（4）在放射治疗前<2 个月或在放射治疗和反应评估之间没有给予全身治疗；（5）在连续 FDG-PET/CT 上检测到的≥1 处未照射病变中完全代谢缓解（CMR）。对 2016 年至 2018 年治疗的所有 FL 累及部位放射治疗患者进行了系统性回顾。
共发现 7 例远处退缩反应，其中 4 例为 FL。在所有病例中，ISRT 体积内和≥1 处未照射的病变均出现了 CMR。分别有 1 例为套细胞淋巴瘤（2 次分割，每次 4 Gy）、霍奇金淋巴瘤（3 次分割，每次 20 Gy，然后在同一部位给予 15 次分割，每次 30 Gy）和慢性淋巴细胞白血病的 Richter 转化（10 次分割，每次 30 Gy）。4 例 FL 患者分别接受 2 次分割 4 Gy（n=3）或 4 Gy 后 8 个月接受 15 次分割 30 Gy（n=1）。2016 年至 2018 年，共进行了 29 次 ISRT 治疗多灶性 FL，随后在 29 例患者中检测到 4 例（13.8%）远处退缩反应，其中 9 例患者（44.4%）进行了连续 PET 扫描。2 例初始远处退缩反应后复发的患者接受免疫治疗后，获得了持久的 CMR。
在 7 例患者中，4 例（7 例中的 4 例）在接受 4 Gy 后，2 例（7 例中的 2 例）在对同一部位进行重复 ISRT 后，2 例（7 例中的 2 例）在随后对免疫治疗产生完全反应时，PET 检测到淋巴瘤的远处退缩反应，这与远处效应的免疫基础一致。FL 中的远处退缩反应似乎比以前怀疑的更常见。
