Detailed Abstract
[E-poster]
[EP097] Identifying patients who may benefit from adjuvant chemoradiotherapy for positive or close resection margin after curative resection of pancreatic adenocarcinoma
Byoung Hyuck KIM1, Kyubo KIM2, Jin-Young JANG3, Wooil KWON3, Hongbeom KIM3, Kyung-Hun LEE4, Do-Youn OH4, Haeryoung KIM5, Kyung Bun LEE5, Eui Kyu CHIE*6, 7
1Radiation Oncology, Seoul National University Boramae Medical Center, Korea
2Radiation Oncology, Ewha Womans University College of Medicine, Korea
3Surgery, Seoul National University College of Medicine, Korea
4Internal Medicine, Seoul National University College of Medicine, Korea
5Pathology, Seoul National University College of Medicine, Korea
6Radiation Oncology, Seoul National University College of Medicine, Korea
7Institute of Radiation Medicine, Medical Research Center, Seoul National University, Korea
Introduction : No optimal adjuvant treatment strategy has been established for positive or close resection margin (RM) after curative resection of pancreatic adenocarcinoma, which should be distinguished from that of R0 resection. This study was conducted to identify patients who may benefit from adjuvant chemoradiotherapy (CRT) after R1 resection.
Methods : From 2004 to 2015, total of 472 patients with pancreatic adenocarcinoma underwent curative resection. After excluding patients with RM > 2mm or unknown, remaining 217 patients were retrospectively analyzed.
Results : Among various margin status, only the vascular RM showed a significant difference in outcome according to the median cutoff. Two-year overall survival (OS) and time to recurrence (TTR) for noTx (didn’t receive any adjuvant therapy), chemotherapy alone (CTx), and CRT group were 34.5%, 52.2%, and 57.8%, and 27.7%, 24.0%, and 33.0%, respectively. Significant survival benefits of CRT over CTx (HR 0.602, p = 0.020 for OS; HR 0.599, p = 0.016 for TTR) were demonstrated in multivariate analysis. In the subgroup analysis, such benefits of adjuvant CRT over CTx was observed only in patients with head tumor & vascular RM > 0.5mm, but not in patients with body/tail tumor or vascular RM ≤ 0.5mm. In the CRT group, radiation dose≥54 Gy was significantly associated with better TTR and OS.
Conclusions : Adjuvant CRT could improve TTR and OS compared to adjuvant CTx alone in patients with close RM. Radiation dose escalation may be beneficial when feasible. Modern CRT regimen–based randomized evidence is needed for these high risk patients.
Methods : From 2004 to 2015, total of 472 patients with pancreatic adenocarcinoma underwent curative resection. After excluding patients with RM > 2mm or unknown, remaining 217 patients were retrospectively analyzed.
Results : Among various margin status, only the vascular RM showed a significant difference in outcome according to the median cutoff. Two-year overall survival (OS) and time to recurrence (TTR) for noTx (didn’t receive any adjuvant therapy), chemotherapy alone (CTx), and CRT group were 34.5%, 52.2%, and 57.8%, and 27.7%, 24.0%, and 33.0%, respectively. Significant survival benefits of CRT over CTx (HR 0.602, p = 0.020 for OS; HR 0.599, p = 0.016 for TTR) were demonstrated in multivariate analysis. In the subgroup analysis, such benefits of adjuvant CRT over CTx was observed only in patients with head tumor & vascular RM > 0.5mm, but not in patients with body/tail tumor or vascular RM ≤ 0.5mm. In the CRT group, radiation dose≥54 Gy was significantly associated with better TTR and OS.
Conclusions : Adjuvant CRT could improve TTR and OS compared to adjuvant CTx alone in patients with close RM. Radiation dose escalation may be beneficial when feasible. Modern CRT regimen–based randomized evidence is needed for these high risk patients.
SESSION
E-poster
E-Session 7/27 ~ 7/29 ALL DAY