Eckstein Jacob, Choi J Isabelle, Lozano Alicia, Ohri Nitin, Press Robert, Hasan Shaakir, Kabarriti Rafi, Chang John, Urbanic James, Durci Michael, Mohammed Nasiruddin, Stevens Craig, Tsai Henry, Apisarnthanarax Smith, Regine William, Vargas Carlos, Nichols Romaine, Herman Joseph, Simone Charles B, Chhabra Arpit
Northwell Health, Department of Radiation Medicine, New Hyde Park, New York.
New York Proton Center, New York, New York.
Adv Radiat Oncol. 2023 Apr 23;8(5):101250. doi: 10.1016/j.adro.2023.101250. eCollection 2023 Sep-Oct.
Compared with photon-based techniques, proton beam radiation therapy (PBT) may improve the therapeutic ratio of radiation therapy (RT) for locally advanced pancreatic cancer (LAPC), but available data have been limited to single-institutional experiences. This study examined the toxicity, survival, and disease control rates among patients enrolled in a multi-institutional prospective registry study and treated with PBT for LAPC.
Between March 2013 and November 2019, 19 patients with inoperable disease across 7 institutions underwent PBT with definitive intent for LAPC. Patients received a median radiation dose/fractionation of 54 Gy/30 fractions (range, 50.4-60.0 Gy/19-33 fractions). Most received prior (68.4%) or concurrent (78.9%) chemotherapy. Patients were assessed prospectively for toxicities using National Cancer Institute Common Terminology Criteria for Adverse Events, version 4.0. Kaplan-Meier analysis was used to analyze overall survival, locoregional recurrence-free survival, time to locoregional recurrence, distant metastasis-free survival, and time to new progression or metastasis for the adenocarcinoma cohort (17 patients).
No patients experienced grade ≥3 acute or chronic treatment-related adverse events. Grade 1 and 2 adverse events occurred in 78.7% and 21.3% of patients, respectively. Median overall survival, locoregional recurrence-free survival, distant metastasis-free survival, and time to new progression or metastasis were 14.6, 11.0, 11.0, and 13.9 months, respectively. Freedom from locoregional recurrence at 2 years was 81.7%. All patients completed treatment with one requiring a RT break for stent placement.
Proton beam RT for LAPC offered excellent tolerability while still maintaining disease control and survival rates comparable with dose-escalated photon-based RT. These findings are consistent with the known physical and dosimetric advantages offered by proton therapy, but the conclusions are limited owing to the patient sample size. Further clinical studies incorporating dose-escalated PBT are warranted to evaluate whether these dosimetric advantages translate into clinically meaningful benefits.
与基于光子的技术相比，质子束放射治疗（PBT）可能会提高局部晚期胰腺癌（LAPC）放射治疗（RT）的治疗比率，但现有数据仅限于单机构经验。本研究调查了参加多机构前瞻性登记研究并接受PBT治疗LAPC的患者的毒性、生存率和疾病控制率。
2013年3月至2019年11月期间，7家机构的19例无法手术的患者接受了旨在治疗LAPC的PBT。患者接受的中位放射剂量/分割为54 Gy/30次分割（范围为50.4 - 60.0 Gy/19 - 33次分割）。大多数患者接受过先前（68.4%）或同期（78.9%）化疗。使用美国国立癌症研究所不良事件通用术语标准第4.0版对患者的毒性进行前瞻性评估。采用Kaplan-Meier分析来分析腺癌队列（17例患者）的总生存期、局部区域无复发生存期、局部区域复发时间、远处转移无复发生存期以及出现新进展或转移的时间。
没有患者经历≥3级急性或慢性治疗相关不良事件。1级和2级不良事件分别发生在78.7%和21.3%的患者中。中位总生存期、局部区域无复发生存期、远处转移无复发生存期以及出现新进展或转移的时间分别为14.6个月、11.0个月、11.0个月和13.9个月。2年时局部区域无复发率为81.7%。所有患者均完成了治疗，其中1例因放置支架需要中断放疗。
LAPC的质子束RT耐受性良好，同时仍能维持疾病控制和生存率，与剂量递增的基于光子的RT相当。这些发现与质子治疗已知的物理和剂量学优势一致，但由于患者样本量的原因，结论有限。有必要进行进一步纳入剂量递增PBT的临床研究，以评估这些剂量学优势是否能转化为具有临床意义的益处。
