Early [18F]Fluorodeoxyglucose Positron Emission Tomography at Two Days of Gefitinib Treatment Predicts Clinical Outcome in Patients with Adenocarcinoma of the Lung

Han

et al. 2015

Nucl Med Mol Imaging

Purpose The BRAF mutation, a potential prognostic factor in papillary thyroid carcinoma (PTC), is associated with a high expression of the glucose transporter gene. We investigated which clinicopathologic factors, including BRAF mutation status, influence 18 F-fluoro-2-deoxyglucose ( 18 F-FDG) avidity. Methods We retrospectively reviewed 55 patients who underwent BRAF analysis from biopsy-confirmed PTC and 18 F-FDG positron emission tomography/computed tomography within 6 months before undergoing thyroid surgery from September 2008 to August 2014. Tumors were considered to be 18 F-FDG avid if the uptake was greater than that of the liver. 18 F-FDG uptake of PTCs was also analyzed semiquantitatively using SUV max . The association between 18 F-FDG avidity and clinicopathologic variables (age, tumor size, perithyroidal extension, cervical lymph node status, and BRAF mutation status) was investigated. Results Twenty-nine (52.7 %) of 55 patients had 18 F-FDGavid PTCs. PTCs with the BRAF mutation showed higher 18 F-FDG avidity (24/38, 63.2 %) than those without (5/17, 29.4 %). The BRAF mutation (p=0.025) and tumor size (p= 0.003) were significantly associated with 18 F-FDG avidity in univariate analysis, and the BRAF mutation status remained significant after adjusting for tumor size in multivariate analysis (p=0.015). In the subgroup of tumor size≥1 cm, the BRAF mutation was the only factor significantly associated with 18 F-FDG avidity (p=0.021). The mean SUV max of PTCs with the BRAF mutation was significantly higher than that of those without (4.89±6.12 vs. 1.96±1.10, p=0.039). Conclusions The BRAF mutation must be one of the most important factors influencing 18 F-FDG avidity in PTCs, especially in those with a tumor size≥1 cm.

Section: Discussionmentioning

confidence: 99%

Association Between 18F-FDG Avidity and the BRAF Mutation in Papillary Thyroid Carcinoma

Han

et al. 2015

Nucl Med Mol Imaging

“…One could argue that this cutoff might be suboptimal for early assessment (within 1 wk of treatment initiation). Takahashi et al (27) used 18 F-FDG PET/CT for gefitinib response monitoring after 2 d and 1 mo of treatment of 20 patients with advanced lung adenocarcinoma and suggested a cutoff of 20% for a decrease in the SUV max at early monitoring. However, the size of the study did not permit testing of other cutoff values.…”

Section: Discussionmentioning

confidence: 99%

Timing of Metabolic Response Monitoring During Erlotinib Treatment in Non–Small Cell Lung Cancer

et al. 2014

The purpose of this study was to prospectively evaluate the timing of metabolic response monitoring with 18 F-FDG PET of (neoadjuvant) erlotinib treatment in patients with early-stage non-small cell lung cancer. Methods: This study was designed as an open-label phase II trial performed in 4 hospitals in The Netherlands. Patients received preoperative erlotinib (150 mg) once daily for 3 wk. Response evaluation was performed after 4-7 d and at 3 wk with 18 F-FDG PET/CT scans. Tumor 18 F-FDG uptake and changes were measured as standardized uptake values (SUVs). The metabolic response was classified on the basis of European Organization for Research and Treatment of Cancer criteria (.25% decrease in the maximum SUV) and was compared with histopathologic regression as observed in the resection specimen. Results: From December 2006 to November 2010, 60 patients with non-small cell lung cancer eligible for surgical resection were enrolled in this study. For 43 patients (18 men and 25 women), baseline 18 F-FDG PET/CT scans as well as both monitoring scans and histopathologic response monitoring were available. A partial metabolic response on 18 F-FDG PET/CT scans was observed for 10 patients (23%) after 1 wk and for 14 patients (33%) after 3 wk. Histopathologic examination revealed regression (necrosis of .50%) in 11 patients (26%). In these patients, the maximum SUV decreased by a mean of 17% within 1 wk and a mean of 31% at 3 wk. Seven patients were identified as responders within 1 wk. Conclusion: Response monitoring with 18 F-FDG PET/CT within 1 wk after the start of erlotinib treatment identified approximately 64% of histopathologic responders on the basis of European Organization for Research and Treatment of Cancer criteria.

“…PET response assessed after 2 d of treatment with gefitinib predicted long-term outcome of patients with advanced non-small cell lung cancer (39). However, large diffuse B-cell lymphoma might require longer time for metabolic response (40).…”

Section: Discussionmentioning

confidence: 99%

Early PET/CT Scan Is More Effective Than RECIST in Predicting Outcome of Patients with Liver Metastases from Colorectal Cancer Treated with Preoperative Chemotherapy Plus Bevacizumab

et al. 2013

Markers predictive of treatment effect might be useful to improve the treatment of patients with metastatic solid tumors. Particularly, early changes in tumor metabolism measured by PET/CT with 18 F-FDG could predict the efficacy of treatment better than standard dimensional Response Evaluation Criteria In Solid Tumors (RECIST) response. Methods: We performed PET/CT evaluation before and after 1 cycle of treatment in patients with resectable liver metastases from colorectal cancer, within a phase 2 trial of preoperative FOLFIRI plus bevacizumab. For each lesion, the maximum standardized uptake value (SUV) and the total lesion glycolysis (TLG) were determined. On the basis of previous studies, a # 250% change from baseline was used as a threshold for significant metabolic response for maximum SUV and, exploratively, for TLG. Standard RECIST response was assessed with CT after 3 mo of treatment. Pathologic response was assessed in patients undergoing resection. The association between metabolic and CT/RECIST and pathologic response was tested with the McNemar test; the ability to predict progressionfree survival (PFS) and overall survival (OS) was tested with the Log-rank test and a multivariable Cox model. Results: Thirtythree patients were analyzed. After treatment, there was a notable decrease of all the parameters measured by PET/CT. Early metabolic PET/CT response (either SUV-or TLG-based) had a stronger, independent and statistically significant predictive value for PFS and OS than both CT/RECIST and pathologic response at multivariate analysis, although with different degrees of statistical significance. The predictive value of CT/RECIST response was not significant at multivariate analysis. Conclusion: PET/CT response was significantly predictive of long-term outcomes during preoperative treatment of patients with liver metastases from colorectal cancer, and its predictive ability was higher than that of CT/RECIST response after 3 mo of treatment. Such findings need to be confirmed by larger prospective trials.