76P - Interpretation and prognostic value of PET-CT after induction chemotherapy with or without radiation in IIIA-N2 non-small cell lung cancer patients...

Date 07 May 2017
Event ELCC 2017
Session Poster Display Session
Topics Thoracic Malignancies
Non-Small Cell Lung Cancer
Presenter Jong Hoon Lee
Citation Annals of Oncology (2017) 28 (suppl_2): ii24-ii27. 10.1093/annonc/mdx092
Authors J.H. Lee
  • Radiation Oncology, St. Vincent's Hospital, The Catholic University of Korea, 16247 - Suwon/KR

Abstract

Background

We evaluated the correlation of clinical staging on positron emission tomography-computed tomography (PET-CT) and pathologic staging and the prognostic value of PET-CT after induction chemotherapy in patients with locally advanced non-small cell lung cancer (NSCLC).

Methods

We analyzed 42 cases of clinical stage IIIA-N2 NSCLC who received 2 to 4 cycles of pre-operative chemotherapy with or without radiation followed by curative resection. The maximum standard uptake value (SUVmax) of the suspected lesion on PET-CT was recorded. PET-CT findings after induction chemotherapy were compared with those of initial PET-CT and pathology after surgery.

Results

The accuracy of PET-CT in restaging of the primary tumor after induction chemotherapy was 50.0%. 18 (42.8%) of 42 patients were underestimated ycT stage, and 3 (7.1%) of 42 patients was overestimated ycT stage by PET-CT scan. The accuracy of PET-CT in restaging of the nodal disease was 71.4%. 6 (14.3%) of 42 patients were underestimated ycN stage, and 6 (14.3%) of 42 patients were overestimated ycN stage as compared with pathologic staging. The 2-year overall survival (OS) and relapse-free survival (RFS) rate were 68.5% and 40.9%, respectively. Complete responders (ycT0N0M0) on PET-CT after induction chemotherapy had a significantly longer RFS time than did incomplete responders (28.3 months versus 9.1 months, P = 0.021).

Conclusions

Complete response on PET-CT after induction chemotherapy with or without radiation was a good prognostic indicator for RFS in stage IIIA-N2 NSCLC patients who received surgery. However, response evaluation on PET-CT after induction chemotherapy should be interpreted with caution due to its unacceptable accuracy.

Clinical trial identification

None declared.

Legal entity responsible for the study

Jong Hoon Lee

Funding

None

Disclosure

The author has declared no conflicts of interest.