The aim of the study was to evaluate the prognostic significance of intratumoral metabolic heterogeneity on pretreatment 18F-FDG PET/CT in patients with lung cancer who were pathologically N0 (pN0) after curative surgical resection.
We examined 119 patients (M/F = 79/40; mean age, 64.6 ± 9.0 years) who had undergone pretreatment 18F-FDG PET/CT and were diagnosed as pN0 after curative surgery for adenocarcinoma (ADC; n = 67) or squamous cell carcinoma (SQCC; n = 52). Heterogeneity factor (HF) and other metabolic parameters (SUVmax, metabolic tumor volume [MTV] and total lesion glycolysis [TLG]) for the primary lesions were measured, and the results were analyzed for recurrence. The HF, defined as the derivative of the volume-threshold function from 20% to 80%, was computed for primary lesions. Univariate and multivariate analyses for recurrence were performed using the Kaplan-Meier method and using the Cox proportional hazards model.
SUVmax, MTV, TLG, and HF were statistically different between patients with ADC and SQCC. Forty-one (34.5%) of 119 patients experienced recurrence (ADC, 25/67 = 37.3% vs. SQCC, 16/52 = 30.8%). Results of univariate analysis indicate that SUVmax, MTV, TLG, and HF in ADC and TLG and HF in SQCC were predictors for recurrence. After adjusting for sex, age, and histological grade in multivariate analysis, high SUVmax, MTV, TLG, and HF in ADC exhibited an association with increased risk of recurrence.
Metabolic parameters and heterogeneity of primary tumor on pretreatment 18F-FDG PET/CT can predict recurrence in pN0 NSCLC patients of ADC type who have undergone curative surgery but not in patients of SQCC type.
From the Department of Nuclear Medicine, Kyungpook National University School of Medicine and Hospital, Daegu, Republic of Korea.
Received for publication November 2, 2014; revision accepted April 25, 2015.
Conflicts of interest and sources of funding: This work was supported by a grant from the Medical Cluster R&D Support Project of Daegu Gyeongbuk Medical Innovation Foundation, Republic of Korea (HT13C0002); a grant (A111345) from the Korea Health Technology R&D Project, Ministry of Health & Welfare, Republic of KOREA; a grant from the National Nuclear R&D Program through the National Research Foundation of Korea (NRF) funded by the Ministry of Education, Science and Technology (No.2012M2A2A7014020); and a grant from the National Research Foundation of Korea (NRF) grant funded by the Korea government (MEST) (No. 2009-0078222, 2009-0078234); a grant (HI15C0001) of the Korea Health Technology R&D Project through the Korea Health Industry Development Institute, funded by the Ministry of Health & Welfare, Republic of Korea. The authors declare that they have no conflict of interest.
Correspondence to: Byeong-Cheol Ahn, MD, PhD, Department of Nuclear Medicine Kyungpook National University School of Medicine and Hospital 50, Samduk 2-ga, Jung Gu, Daegu, 700–721, Republic of Korea. E-mail: firstname.lastname@example.org.