TY - JOUR
T1 - Ablative Radiation Therapy in Oligometastatic Pancreatic Cancer to Delay Polyprogression, Limit Chemotherapy, and Improve Outcomes
AU - Elamir, Ahmed M.
AU - Karalis, John D.
AU - Sanford, Nina Niu
AU - Polanco, Patricio M.
AU - Folkert, Michael R.
AU - Porembka, Matthew R.
AU - Kazmi, Syed Ali
AU - Maddipati, Ravikanth
AU - Zeh, Herbert J.
AU - Timmerman, Robert D.
AU - Zhang, Song
AU - Ligorio, Matteo
AU - Beg, Muhammad Shaalan
AU - Aguilera, Todd A.
N1 - Publisher Copyright:
© 2022 Elsevier Inc.
PY - 2022/11/15
Y1 - 2022/11/15
N2 - Purpose: The oligometastatic state is observed in patients across many malignancies, with increased recognition regarding improved outcomes after local therapies. However, there is limited data specifically regarding pancreatic ductal adenocarcinoma. We hypothesized that an oligometastatic pancreatic ductal adenocarcinoma (OPanc) phenotype would benefit from stereotactic ablative radiation therapy (SABR) to all active metastatic sites. Here, we report our institutional experience of SABR-treated OPanc to evaluate the feasibility of the approach. Methods and Materials: A retrospective review of patients with synchronous or metachronous OPanc (1 to 5 metastases) who received SABR to all active metastatic sites was performed. We identified a comparable group of patients with similar metastatic burden, range of CA19-9 levels, and no progression for at least 5 months who did not receive SABR. We compared overall survival as the primary outcome, and polyprogression-free survival and time off chemotherapy as the secondary exploratory assessments. A third group presenting with stage IV pancreatic ductal adenocarcinoma and more than 5 distant lesions (polymetastatic) was identified to help define expected outcomes after polyprogression. Results: Our study included 20 patients with OPanc receiving SABR and 21 who did not. SABR was delivered to 38 metastatic tumors. Out of the 20 SABR-treated OPanc patients, 17 (85%) had 6 or more months of time off chemotherapy, compared with 7 patients (33.3%) among the chemotherapy-treated group. Median polyprogression-free survival was 40 and 14 months (hazard ratio = 0.2; 95% confidence interval, 0.07-0.54; P = .0009), and overall survival was 42 and 18 months (hazard ratio = 0.21; 95% confidence interval, 0.08-0.53; P = .0003), for SABR- and chemotherapy-treated cohorts, respectively. Conclusions: Management of OPanc with SABR as local regional therapy could improve outcomes in a selected population and warrants prospective evaluation.
AB - Purpose: The oligometastatic state is observed in patients across many malignancies, with increased recognition regarding improved outcomes after local therapies. However, there is limited data specifically regarding pancreatic ductal adenocarcinoma. We hypothesized that an oligometastatic pancreatic ductal adenocarcinoma (OPanc) phenotype would benefit from stereotactic ablative radiation therapy (SABR) to all active metastatic sites. Here, we report our institutional experience of SABR-treated OPanc to evaluate the feasibility of the approach. Methods and Materials: A retrospective review of patients with synchronous or metachronous OPanc (1 to 5 metastases) who received SABR to all active metastatic sites was performed. We identified a comparable group of patients with similar metastatic burden, range of CA19-9 levels, and no progression for at least 5 months who did not receive SABR. We compared overall survival as the primary outcome, and polyprogression-free survival and time off chemotherapy as the secondary exploratory assessments. A third group presenting with stage IV pancreatic ductal adenocarcinoma and more than 5 distant lesions (polymetastatic) was identified to help define expected outcomes after polyprogression. Results: Our study included 20 patients with OPanc receiving SABR and 21 who did not. SABR was delivered to 38 metastatic tumors. Out of the 20 SABR-treated OPanc patients, 17 (85%) had 6 or more months of time off chemotherapy, compared with 7 patients (33.3%) among the chemotherapy-treated group. Median polyprogression-free survival was 40 and 14 months (hazard ratio = 0.2; 95% confidence interval, 0.07-0.54; P = .0009), and overall survival was 42 and 18 months (hazard ratio = 0.21; 95% confidence interval, 0.08-0.53; P = .0003), for SABR- and chemotherapy-treated cohorts, respectively. Conclusions: Management of OPanc with SABR as local regional therapy could improve outcomes in a selected population and warrants prospective evaluation.
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U2 - 10.1016/j.ijrobp.2022.07.019
DO - 10.1016/j.ijrobp.2022.07.019
M3 - Article
C2 - 35896145
AN - SCOPUS:85139072101
SN - 0360-3016
VL - 114
SP - 792
EP - 802
JO - International Journal of Radiation Oncology Biology Physics
JF - International Journal of Radiation Oncology Biology Physics
IS - 4
ER -