715P - Does reduced dose of FOLFIRINOX guarantee tumor response in unresectable pancreatic cancer? : Suggestion for the minimal relative dose intensity

Date 29 September 2014
Event ESMO 2014
Session Poster Display session
Topics Anti-Cancer Agents & Biologic Therapy
Pancreatic Cancer
Presenter Jong-chan Lee
Citation Annals of Oncology (2014) 25 (suppl_4): iv210-iv253. 10.1093/annonc/mdu334
Authors J. Lee, Y.S. Lee, K. Paik, H.W. Kim, J. Kim, J. Hwang
  • Internal Medicine, Seoul National University Bundang Hospital, 463-707 - Seongnam/KR

Abstract

Aim

Since PRODIGE4-ACCORD11 trial showed the superior activity of FOLFIRINOX (5-fluorouracil [5-FU], oxaliplatin, and irinotecan) than gemcitabine, FOLFIRINOX has been widely applied to the patients with pancreatic cancer as the first-line chemotherapy. Recently there have been published several reports about modified FOLFIRINOX as a concept of dose reduction. However, it is still unclear how much reduction would be promising as a minimal threshold of effective dose. The aim of this study is to investigate minimal relative dose intensity of FOLFIRINOX to expect tumor response in unresectable pancreatic cancer.

Methods

A total of 44 patients who were diagnosed with unresectable pancreatic adenocarcinoma from 2012 to 2014 were retrospectively reviewed. All patients were treated with FOLFIRINOX as 1st-line treatment. Assuming four cycles of standard FOLFIRINOX dose as a 100% dose, actually delivered cumulative dose of each patient was converted to relative dose intensity (RDI, %) during the first 8 weeks. Patients were divided into three groups depending on RDI; group A, RDI ≥ 80%; group B, 70 ≤ RDI < 80%; group C, 50 ≤ RDI < 70%. Response rate and toxicity were evaluated among three groups.

Results

Of 44 patients, total 27 were eligible. Among 27 eligible patients, the number of group A, B and C was 8 (30%), 12 (44%) and 7 (26%), respectively. There was no difference between groups in terms of mean age, performance status and stage. The response rates in first 8 weeks were 50%, 42% and 0% in group A, B, C, respectively. The number of grade 4 neutropenia within the 8 weeks was 13%, 16%, and 14%, respectively. The incidence of grade 3/4 diarrhea or nausea was 25%, 33%, and 29%, respectively. There was no statistical difference between group A and B in terms of response rate, whereas group B and C showed significant difference. Grade 3 or more toxicities were not statistically different among three groups.

Conclusions

Dose reduction of FOLFIRINOX might be effective to control unresectable pancreatic cancer. However, less than 70% of RDI of FOLFIRINOX showed significantly low response rate, whereas there was no change in terms of severe side effects. We suggest the 70% of RDI as minimal relative dose intensity to expect tumor response in unresectable pancreatic cancer.

Disclosure

All authors have declared no conflicts of interest.