CHICAGO — Preoperative chemotherapy with radiation demonstrated a significant survival benefit compared with surgery alone among patients with borderline resectable pancreatic cancer, according to preliminary results of the phase 3 randomized controlled PREOPANC trial presented at the ASCO Annual Meeting.
More patients who received chemoradiotherapy before surgery achieved 2-year OS than patients who started therapy with surgery (42% vs. 30%).
“Patients with pancreatic cancer have a very poor prognosis. Surgical removal is only possible in a minority of patients and is followed by adjuvant chemotherapy as the standard of care — up until now,” Geertjan Van Tienhoven, MD, PhD, radiation oncologist in the department of radiation oncology at Academic Medical Center in Amsterdam, said during a press conference.
Previously data suggested neoadjuvant treatment may be beneficial for patients with pancreatic cancer.
Van Tienhoven and colleagues conducted a multicenter trial to evaluate and compare preoperative chemoradiotherapy (n = 119) with immediate surgery (n = 127) among patients with borderline resectable pancreatic cancer. All patients received adjuvant chemotherapy.
Preoperative chemoradiotherapy included 15 doses of 2.4 Gy radiation plus 1,000mg/m² gemcitabine on days 1, 8 and 15, preceded and followed by one cycle of gemcitabine.
OS served as the primary endpoint. Secondary endpoints included resection rate, DFS, distant metastases-free interval, locoregional recurrence-free interval and toxicity.
Results of the intention-to-treat analysis showed OS significantly increased with preoperative chemoradiotherapy (median, 17.1 months vs. 13.7 months; HR = 0.74; P = .074).
Chance for microscopically complete removal of the tumor during surgery was 63% with preoperative treatment vs. 31% with immediate surgery.
Preoperative treatment was also associated with prolonged DFS (median, 11.2 months vs. 7.9 months; HR = 0.67; P = .01), distant metastases-free interval (median, 17.1 months vs. 10.2 months; HR = 0.71; P = .013) and locoregional recurrence-free interval (median, 11.2 months vs. not reached; HR = 0.55; P = .002).
A subgroup analysis including patients who underwent successful resection showed a median OS of 42.1 months with preoperative chemoradiotherapy vs. 16.8 months with immediate surgery.
“I must stress that these are preliminary findings and we will need 26 more events before the final analysis can meet statistical significance,” Van Tienhoven said. “These final results have to be awaited before we can draw a definitive conclusion.” – by Jennifer Southall
Van Tienhoven G, et al. LBA4002. Presented at: ASCO Annual Meeting; June 1-5, 2018; Chicago.
Disclosures: The study was funded by the Dutch Cancer Society KWF. Van Tienhoven reports no relevant financial disclosures. Please see the abstract for all other author’s relevant financial disclosures.