ESTRO 2023 - Abstract Book

S740

Monday 15 May 2023

ESTRO 2023

nature of any adverse events were recorded in accordance with the National Cancer Institute Common Toxicity Criteria (version 4.0) scale. The trial registration number is NCT05399394. Results Of the 54 eligible patients (31 men, 23 women), median age was 63 years (range, 48-75 years). Twenty patients (37%) were excluded because of the evidence of metastatic disease, and thus thirty-four patients were consequently enrolled. Of these, fourteen patients (41%) had locally advanced unresectable tumours, twenty patients (59%) had borderline resectable disease. Five patients (14.7%) had a progression of disease after induction chemotherapy. Twenty-nine patients received concomitant CRT (Figure). All patients completed the combined treatment. Eighteen patients were evaluated with surgical exploration, and sixteen patients (55%) underwent surgical radical resection. Two patients are awaiting surgical evaluation. R0 resection was achieved in all 16 of the 29 eligible patients (55%). The median follow-up was 17 months (range, 6 to 63 months). Median OS and median PFS in patients who have completed CRT were 17 months (95% CI, 13 to 22) and 12 months (95% CI, 9.8 to 16.1), respectively. One-year OS, one-year PFS, one-year LPFS and one-year MFS were 88%, 53%, 80% and 65%, respectively. Patients who underwent resection had a significant longer median OS compared with non resected patients (22.4 months vs 13.2 months, p=0.03). Median PFS for resected patients was 14.5 months compared with 8.7 months for non resected patients (p<0.001). Treatment-related grade 3 to 4 toxicities included neutropenia (20%), nausea and vomiting (7%), diarrhea (4%).

Conclusion FOLFIRINOX followed by long-course CRT in borderline resectable and locally advanced unresectable PDAC results in high rates of R0 resection and prolonged median PFS and median OS. PD-0893 Utility of neoadjuvant CT with/without SBRT to improve outcomes of non-metastatic pancreatic cancer P. Pathare 1 , D.R. Engineer 1 , D.R. Krishnatry 2 , D.S. Gudi 1 , D. Bhandare 3 , D. Chaudhari 3 , D.V. Ostwal 4 , D.A. Ramaswamy 4 , D.S. Shrikhande 3 1 Tata Memorial Hospital, Radiation Oncology, Mumbai, India; 2 Tata Memorial Hospital, Radiation oncology, Mumbai, India; 3 Tata Memorial Hospital, Surgical Oncology, Mumbai, India; 4 Tata Memorial Hospital, Medical Oncology, Mumbai, India Purpose or Objective To evaluate the survival outcomes of all the non-metastatic resectable pancreatic cancer (RPC), borderline resectable pancreatic cancer (BRPC) and locally advanced pancreatic cancer (LAPC) pancreatic cancer patients. Materials and Methods We analyzed all the consecutive patients diagnosed as carcinoma head of pancreas without metastasis treated at our center. RPC patients underwent upfront surgery with or without adjuvant treatment whereas the BRPC patients received neoadjuvant chemotherapy (NACT) with mFOLFIRINOX or NAB-PACLITAXEL (4-6 cycles) followed by surgical assessment. Patients with partial response (PR) were surgically explored, those with stable disease(SD)received stereotactic body RT(SBRT) and CT followed by surgical assessment. LAPC patients, received 6 to 8 cycles of chemotherapy and received SBRT at the discretion of treating physician. SBRT consisted of 42 -45 Gy over 5 fractions in 10 days. Results Between 2016-2020, 416 patients were treated. Of these 92(22.1%) staged as RPC ,153(36.7%) as BRPC and 171(41.1%) as LAPC. All the 92 RPC patients underwent upfront surgery. One third (28.1%) of the patients with BRPC either defaulted or progressed after NACT and 110(71.8%) patients were further evaluated. Post NACT,39(25.4%) patients with PR were surgically explored,32(20.9%) underwent R0/R1 resection and 71(46.4%) patients with SD not amenable for R0 resection received additional SBRT and CT. Of these, 29(18.9%) were surgically explored and 22(14.3%) underwent R0/R1 resection. Out of 171(41.1%) diagnosed with LAPC, 135 patients could receive 6 to 8 cycles of chemotherapy and 84 (49%) patients additionally received SBRT. Whereas 51 patients continued on CT.