Open AccessPrognostic value of post-induction chemotherapy 18F-FDG PET-CT in stage II/III non-small cell lung cancer before (chemo-) radiation
Author(s) -
Julien Ganem,
S. Thureau,
Pierrick Gouel,
Bernard Dubray,
Mathieu Salaün,
Edgar Texte,
Pierre Véra
Publication year - 2019
Publication title -
plos one
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.99
H-Index - 332
ISSN - 1932-6203
DOI - 10.1371/journal.pone.0222885
Subject(s) - medicine , stage (stratigraphy) , lung cancer , proportional hazards model , chemotherapy , induction chemotherapy , radiation therapy , oncology , retrospective cohort study , concomitant , log rank test , survival analysis , standardized uptake value , positron emission tomography , nuclear medicine , paleontology , biology
Introduction The purpose of our present study was to assess the prognostic impact of FDG PET-CT after induction chemotherapy for patients with inoperable non-small-cell lung cancer (NSCLC). Material and methods This retrospective study included 50 patients with inoperable stage II/III NSCLC from January 2012 to July 2015. They were treated for curative intent with induction chemotherapy, followed by concomitant chemoradiation therapy or sequential radiation therapy. FDG PET-CT scans were acquired at initial staging (PET 1 ) and after the last cycle of induction therapy (PET 2 ). Five parameters were evaluated on both scans: SUVmax, SUVpeak, SUVmean, TLG, MTV, and their respective deltas. The prognostic value of each parameter for overall survival (OS) and progression-free survival (PFS) was evaluated with Cox proportional-hazards regression models. Results Median follow-up was 19 months. PET 1 parameters, clinical and histopathological data were not predictive of the outcome. TLG 2 and ΔTLG were prognostic factors for OS. TLG 2 was the only prognostic factor for PFS. For OS, log-rank test showed that there was a better prognosis for patients with TLG 2 < 69g (HR = 7.1, 95%CI 2.8–18, p = 0.002) and for patients with ΔTLG< -81% after induction therapy (HR = 3.8, 95%CI 1.5–9.6, p = 0.02). After 2 years, the survival rate was 89% for the patients with low TLG 2 vs 52% for the others. We also evaluated a composite parameter considering both MTV 2 and ΔSUVmax. Patients with MTV 2 > 23cc and ΔSUVmax> -55% had significantly shorter OS than the other patients (HR = 5.7, 95%CI 2.1–15.4, p< 0.01). Conclusion Post-induction FDG PET might be an added value to assess the patients’ prognosis in inoperable stage II/III NSCLC. TLG, ΔTLG as well as the association of MTV and ΔSUVmax seemed to be valuable parameters, more accurate than clinical, pathological or pretherapeutic imaging data.