Comparing 90-Day Postoperative Mortality After Neoadjuvant Proton-Based Versus Photon-Based Chemoradiotherapy for Esophageal Cancer

Pim J J Damen; Peter S N van Rossum; Yiqing Chen; Chike O Abana; Zhongxing Liao; Brian P Hobbs; Radhe Mohan; Mariela Blum-Murphy; Wayne L Hofstetter; Steven H Lin

doi:10.1016/j.ijpt.2024.100012

Comparing 90-Day Postoperative Mortality After Neoadjuvant Proton-Based Versus Photon-Based Chemoradiotherapy for Esophageal Cancer

Int J Part Ther. 2024 Apr 24:11:100012. doi: 10.1016/j.ijpt.2024.100012. eCollection 2024 Mar.

Authors

Pim J J Damen^{1

2}, Peter S N van Rossum^{1

3}, Yiqing Chen⁴, Chike O Abana¹, Zhongxing Liao¹, Brian P Hobbs⁵, Radhe Mohan⁶, Mariela Blum-Murphy⁷, Wayne L Hofstetter⁸, Steven H Lin¹

Affiliations

¹ Department of Radiation Oncology, The University of Texas MD Anderson Cancer Center, Houston, Texas, USA.
² Department of Radiotherapy, Erasmus Medical Center Cancer Institute, Rotterdam, the Netherlands.
³ Department of Radiation Oncology, Amsterdam UMC, Amsterdam, the Netherlands.
⁴ Department of Biostatistics and Data Science, University of Texas Health Science Center, Houston, Texas, USA.
⁵ Department of Population Health, The University of Austin Dell Medical School, Austin, Texas, USA.
⁶ Department of Radiation Physics, The University of Texas MD Anderson Cancer Center, Houston, Texas, USA.
⁷ Department of Gastrointestinal Medical Oncology, The University of Texas. MD Anderson Cancer Center, Houston, Texas, USA.
⁸ Department of Thoracic and Cardiovascular Surgery, The University of Texas MD Anderson Cancer Center, Houston, Texas, USA.

Abstract

Purpose: Evidence suggests that proton-beam therapy (PBT) results in less toxicity and postoperative complications compared to photon-based radiotherapy in patients who receive chemoradiotherapy followed by esophagectomy for cancer. Ninety-day mortality (90DM) is an important measure of the postoperative (nononcologic) outcome as proxy of quality-of-care. We hypothesize that PBT could reduce 90DM compared to photon-based radiotherapy.

Materials and methods: From a single-center retrospective database patients treated with chemoradiotherapy before esophagectomy for cancer were selected (1998-2022). Univariable logistic regression was used to study the association of radiotherapy modality with 90DM. Three separate methods were applied to adjust for confounding bias, including multivariable logistic regression, propensity score matching, and inverse probability of treatment weighting. Stratified analysis for the age threshold that maximized the difference in 90DM (ie, ≥67 vs <67 years) was performed.

Results: A total of 894 eligible patients were included and 90DM was 5/202 (2.5%) in the PBT versus 29/692 (4.2%) in the photon-based radiotherapy group (P = .262). After adjustment for age and tumor location, PBT versus photon-based radiotherapy was not significantly associated with 90DM (P = .491). The 90DM was not significantly different for PBT versus photon-based radiotherapy in the propensity score matching (P = .379) and inverse probability of treatment weighting cohort (P = .426). The stratified analysis revealed that in patients aged ≥67 years, PBT was associated with decreased 90DM (1.3% vs 8.8%; P = .026). Higher age significantly increased 90DM risk within the photon-based radiotherapy (8.8% vs 2.7%; P = .001), but not within the PBT group (1.3% vs 3.2%; P = .651).

Conclusion: No statistically significant difference was observed in postoperative 90DM after esophagectomy for cancer between PBT and photon-based neoadjuvant chemoradiotherapy. However, among older patients a signal was observed that PBT may reduce 90DM risk.

Keywords: 90-day mortality; Chemoradiation; Esophageal cancer; Esophagectomy; Proton-beam therapy.