73PD - Prognostic value of pre- to post-treatment primary tumor metabolic volume reduction on 18F-FDG-PET/CT in a patient cohort with inoperable locally-a...

Date 06 May 2017
Event ELCC 2017
Session Imaging and locally advanced NSCLC
Topics Thoracic Malignancies
Non-Small Cell Lung Cancer
Presenter Olarn Roengvoraphoj
Citation Annals of Oncology (2017) 28 (suppl_2): ii24-ii27. 10.1093/annonc/mdx092
Authors O. Roengvoraphoj1, C. Eze1, W. Fendler2, M. Dantes1, C. Belka1, F. Manapov1
  • 1Department Of Radiation Oncology,, Ludwig Maximilians University - Grosshadern, 81377 - München/DE
  • 2Department Of Nuclear Medicine, Ludwig Maximilians University - Grosshadern, 81377 - München/DE

Abstract

Background

Previous studies have shown that primary tumor metabolic volume (PT-MV) on 18F-FDG-PET/CT could serve as a prognostic factor in patients treated with definitive chemoradiotherapy (CRT). We analyzed a correlation between pre- to posttreatment PT-MV reduction during the course of CRT and overall survival.

Methods

Sixty-five patients with histologically confirmed NSCLC IIIA-B, treated with definitive CRT in the sequential (21/65 pts, 32.3%) or concurrent (44/65 pts, 67.7%) mode, who underwent 18F-FDG-PET/CT before and about 4-6 weeks after the CRT, were analyzed. Histology yielded 22 (33.8%) adenocarcinomas, 34 (52.3%) squamous cell carcinomas, 8 (12.3%) large-cell carcinomas and 1(1.5%) NSCLC not otherwise specified (NOS). Thirty-five patients (35/65, 53%) were enrolled in randomized clinical trials (16 pts in GILT, 10 pts in InCoDor and 9 pts in BROCAT study CTRT 99/97). The most common concurrent chemotherapy regimen (18/65 pts, 27.7%) consisted of cisplatin given intravenously at a dose of 20mg/m2 on days 1-4 and oral vinorelbine 50mg/m2 on days 1, 8 and 15, every 4 weeks for two courses.

Results

Median OS for the entire cohort was 16 months (95% [CI],11.5–20.5). Complete remission (CR) was reached in 20 (31%), whereas partial and non-response occurred in 31 (48%) and 14 (22%) patients, respectively. The mean change from pre- to posttreatment PT-MV was -51% (range: +125% to -100%). Various cutoffs of PT-MV reduction (100- 90-85-80-70-60 and 50%) after the CRT were analyzed. CR(n = 20) had a median OS of 26 (95 CI: 5-47) vs. 13 months (95 CI:9-16) observed in the rest of treated group (p = 0.01, log-rank test). The results also showed a significant difference in OS favoring patients with PT-MV reduction >90% (n = 18) vs. the rest with a median survival of 24 vs. 13 months, respectively (p = 0.04, log-rank test). However, the association between PT-MV reduction at 80% and 70% and survival showed borderline significance (p = 0.07 and 0.09, log-rank test). PT-MV reduction at 60 and 50% failed to show an effect on OS.

Conclusions

In this inoperable locally-advanced NSCLC cohort, a PT-MV reduction of at least 90% after definitive CRT correlated with improved OS.

Clinical trial identification

Legal entity responsible for the study

Deparment of Radiation Oncology, LMU Munich

Funding

N/A

Disclosure

All authors have declared no conflicts of interest.