Prognostic value of preoperative positron emission tomography in resected stage I non-small cell lung cancer

Beneficial implications of adjuvant chemotherapy for stage IB lung adenocarcinoma exhibiting elevated SUVmax in FDG-PET/CT: a retrospective study from a single center

Background

Controversy surrounds the efficacy of adjuvant chemotherapy (ACT) in the treatment of stage I lung adenocarcinoma (LUAD). The objective of this study was to examine the impact of the maximum standardized uptake value (SUVmax) as measured by 18F-fluorodeoxyglucose positron emission tomography/computed tomography (FDG-PET/CT) on the efficacy of ACT in patients diagnosed with stage I LUAD.

Methods

We scrutinized the medical records of 928 consecutive patients who underwent complete surgical resection for pathological stage I LUAD at our institution. The ideal cut-off value for primary tumor SUVmax in terms of disease-free survival (DFS) and overall survival (OS) was determined using the X-tile software. The Kaplan-Meier method and Cox regression analysis were used for survival analysis.

Results

Based on the SUVmax algorithm, the ideal cutoff values were determined to be 4.9 for DFS and 5.0 for OS. We selected 5.0 as the threshold because OS is the more widely accepted predictive endpoint. In a multivariate Cox regression analysis, SUVmax ≥ 5.0, problematic IB stage, and sublobectomy were identified as independent risk factors for poor DFS and OS. It is noteworthy that patients who were administered ACT had significantly longer DFS and OS than what was observed in the subgroup of patients with pathological stage IB LUAD and SUVmax ≥ 5.0 (p < 0.035 and p ≤ 0.046, respectively). However, there was no observed survival advantage for patients in stages IA or IB who had an SUVmax < 5.0.

Conclusion

The preoperative SUVmax of tumors served as an indicator of the impact of ACT in the context of completely resected pathological stage I LUAD. Notably, patients within the Stage IB category exhibiting elevated SUVmax levels emerged as a subgroup experiencing substantial benefits from postoperative ACT.

Evaluation of recurrence risk for patients with stage I invasive lung adenocarcinoma manifesting as solid nodules based on 18F-FDG PET/CT, imaging signs, and clinicopathological features

BACKGROUND

Stage I lung adenocarcinoma is a heterogeneous group. Previous studies have shown the prognostic evaluation value of PET/CT in this cohort; however, few studies focused on stage I invasive adenocarcinoma manifesting as solid nodules. This study aimed to evaluate the recurrence risk for patients with stage I invasive lung adenocarcinoma manifesting as solid nodules based on ¹⁸F-FDG PET/CT, CT imaging signs, and clinicopathological parameters.

METHODS

We retrospectively enrolled 230 patients who underwent ¹⁸F-FDG PET/CT examination between January 2013 and July 2019. Metabolic parameters: maximum standard uptake value (SUVmax), mean standard uptake value, tumor metabolic volume (MTV), and total tumor glucose digestion were collected. Kaplan-Meier method was used to evaluate recurrence-free survival (RFS), and the multivariate Cox proportional hazards model was used to determine the independent risk factors associated with RFS. The time-dependent receiver operating characteristic curve (ROC) method was used to calculate the optimal cutoff value of metabolic parameters.

RESULTS

The 5-year RFS rate for all patients was 71.7%. Multivariate Cox analysis revealed that the International Association for the Study of Lung Cancer Pathology Committee (IASLC) pathologic grade 3 [Hazard ratio (HR), 3.96; 95% Confidence interval (CI), 1.11-14.09], the presence of cavity sign (HR 5.38; 95% CI 2.23-12.96), SUVmax (HR 1.23; 95% CI 1.13-1.33), and MTV (HR 1.05; 95% CI 1.01-1.08) were potential independent prognostic factors for RFS. Patients with IASLC grade 3, the presence of cavity sign, SUVmax > 3.9, or MTV > 5.4 cm³ were classified as high risk, while others were classified as low risk. There was a significant difference in RFS between the high-risk and low-risk groups (HR 6.04; 95% CI 2.17-16.82, P < 0.001), and the 5-year RFS rate was 94.1% for the low-risk group and 61.3% for the high-risk group.

CONCLUSIONS

We successfully evaluate the recurrence risk of patients with stage I invasive adenocarcinoma manifesting as solid nodules for the first time. The 5-year RFS rate in the high-risk group was significantly lower than in the low-risk group (61.3% vs. 94.1%). Our study may aid in optimizing therapeutic strategies and improving survival benefits for those patients.

A novel diagnostic model for differentiation of lung metastasis from primary lung cancer in patients with colorectal cancer

Objective

This study aimed to evaluate the ¹⁸F-FDG PET/CT in differentiating lung metastasis(LM) from primary lung cancer(LC) in patients with colorectal cancer (CRC).

Methods

A total of 120 CRC patients (80 male, 40 female) who underwent ¹⁸F-FDG PET/CT were included. The diagnosis of primary lung cancer or lung metastasis was based on histopathology The patients were divided into a training cohort and a validation cohort randomized 1:1. Independent risk factors were extracted through the clinical information and ¹⁸F-FDG PET/CT imaging characteristics of patients in the validation cohort, and then a diagnostic model was constructed and a nomograms was made. ROC curve, calibration curve, cutoff, sensitivity, specificity, and accuracy were used to evaluate the prediction performance of the diagnostic model.

Results

One hundred and twenty Indeterminate lung lesions (ILLs) (77 lung metastasis, 43 primary lung cancer) were analyzed. No significant difference in clinical characteristics and imaging features between the training and the validation cohorts (P > 0. 05). Using uni-/multivariate analysis, pleural tags and contour were identified as independent predictors. These independent predictors were used to establish a diagnostic model with areas under the receiver operating characteristic curves (AUCs) of 0.92 and 0.89 in the primary and validation cohorts, respectively. The accuracy rate of the diagnostic model for differentiating LM from LC were higher than that of subjective diagnosis (P < 0.05).

Conclusions

Pleural tags and contour were identified as independent predictors. The diagnostic model of ILLs in patients with CRC could help differentiate between LM and LC.

Relationships between SUVmax of lung adenocarcinoma and different T stages, histological grades and pathological subtypes: a retrospective cohort study in China

OBJECTIVES

Cancer cell has aberrant metabolism. The purpose of this study aimed to investigate relationships between maximum standard uptake value (SUVmax）of ¹⁸fluoro-2-deoxy-d-glucose and T stages, histological grades and pathological subtypes of lung adenocarcinoma.

DESIGN

Retrospective cohort study, employing the Kruskal-Wallis, Bonferroni-Dunn and Mann-Whitney tests to compare SUVmax of different T stages, histological grades and pathological subtypes of lung adenocarcinoma.

SETTING

The outpatients who had aberrant positron emission tomography/CT (PET/CT) images in chest were enrolled this study from August 2016 to November 2018 in Shanghai, China.

PARTICIPANT

Initial 11 270 patients with suspected lung cancer who underwent PET/CT examinations were surveyed. A total of 1454 patients who were diagnosed as lung adenocarcinoma by pathologist were included in this project.

PRIMARY OUTCOME MEASURES

SUVmax value at different tumour-node-metastasis stages of lung adenocarcinoma before surgery.

RESULTS

The mean SUVmax of patients with lung adenocarcinoma was significantly elevated with the increase in T stages. There were significant evident differences in SUVmax among T1a-T1c (p<0.05). However, after the staging of patients was more than T1 stage, SUVmax of T2a, T2b, T2 visceral pleural invasion, T3 and T4 had not dramatic changes. SUVmax value of lung adenocarcinoma in the same T stage group was the highest in patients with the high grade of malignancy and solid-predominant invasive adenocarcinoma.

CONCLUSIONS

SUVmax value was significantly associated with T stages, grades of malignancy and pathological subtypes of lung adenocarcinoma.

Correlation of preoperative PET/computer tomography 18F-fluorodeoxyglucose uptake (maximum standardized uptake value) with prognosis in patients with operated lung cancer

PURPOSE

The aim of this study was to investigate the correlation of preoperative 18F-fluorodeoxyglucose PET/computed tomography maximum standardized uptake value (SUVmax) in operated non-small cell lung cancer (NSCLC) cases with other prognostic parameters and survival.

PATIENTS AND METHODS

NSCLC patients treated by surgical resection were imaged with PET within 60 days before surgery.

RESULTS

Overall, 525 cases consecutive patients were retrospectively reviewed. The median value of SUVmax in a total of 525 cases was 12.1, and the mean was 13.3 ± 7.13. Logistic regression analysis performed to identify the variables that have an impact on SUVmax revealed that histology [hazard ratio (HR: 1.893; 95% CI; P = 0.001) and T status (HR: 8.991; 95% CI; P = 0.000) are correlated with SUVmax. Kaplan-Meier analysis revealed a mean survival of 73.7 ± 1.95 months and a median survival of 85.6 ± 6.03 months. In the group with an SUVmax value of less than 10, the mean survival was 81.9 ± 3.02 months (76.0-87.8), and in the group with SUVmax greater than 10.1, the mean survival was 68.6 ± 2.4 months (63.9-73.3) (P = 0.000). In the multivariate analysis, SUVmax, age, tumor histology, lymph node metastasis, comorbid diseases and complete/incomplete status of the resection were identified as the factors predictive of prognosis.

CONCLUSION

It is seen that preoperative SUVmax is a parameter with prognostic significance at least as much as histopathology, age, complete/incomplete status of resection and lymph node involvement.

Preoperative Maximum Standardized Uptake Value Associated with Recurrence Risk In Early Lung Cancer

BACKGROUND

We aimed to investigate the maximum standardized uptake value (SUVmax) as a predictor of recurrence and timing of recurrence after resection of early-stage non-small cell lung cancer.

METHODS

We retrospectively reviewed patients from a single institution who underwent lobectomy for stage I-IIa non-small cell lung cancer from 2013-2018. Exclusion criteria included preoperative therapy and neuroendocrine histology. We collected recurrence and follow-up data, as well as preoperative SUVmax. A receiver operator characteristic curve was used to identify the optimal SUVmax for predicting recurrence. Kaplan-Meier curves and Cox Regression analyses were used to identify predictors of freedom from recurrence (FFR).

RESULTS

The study included 238 patients, 30(12.6%) of whom developed recurrence. The receiver operator characteristic curve had an area-under-the-curve of 0.671 and identified 4.93 as the optimal SUVmax cut-off. Patients were stratified into groups based on this value; each group included 119 patients. High SUVmax was associated with larger tumor size, poor differentiation, lymphovascular invasion, and shorter FFR. The proportion of patients without recurrence at 5 years in the low- and high-SUVmax groups were 92.4% and 73.4%, respectively (p<0.001). On univariate analysis, poor differentiation (HR:2.35, 95%CI:1.04-5.31; p=0.04), lymphovascular invasion (HR:3.19;95%CI:1.37-7.44;p=0.007), visceral pleural invasion (HR:2.33;95%CI:1.05-5.20;p=0.04), and SUVmax≥4.93 (HR:4.51;95%CI:1.84-11.03;p=0.001) predicted FFR. On multivariable analysis, only SUVmax≥4.93 remained significant (HR:5.36, 95%CI:1.50-19.17; p=0.01).

CONCLUSIONS

SUVmax is independently associated with risk of recurrence after resection of early-stage lung cancer. SUVmax may be a valuable tool in stratifying patients with early-stage lung cancer for adjuvant therapy and surveillance frequency.

Rethinking a Non-Predominant Pattern in Invasive Lung Adenocarcinoma: Prognostic Dissection Focusing on a High-Grade Pattern

Simple Summary

Prognostic considerations for non-predominant histologic patterns are necessary because most lung adenocarcinomas have a mixed histologic pattern. We aimed to identify prognostic stratification by second most predominant pattern of lung adenocarcinomas and to more accurately assess prognostic factors with CT imaging analysis, particularly enhancing non-predominant but high-grade pattern. We confirmed that the second most predominant histologic pattern can stratify lung adenocarcinoma patients according to prognosis. Especially, when the second most predominant pattern was high-grade, recurrence risk increased by 4.2-fold compared with the low-grade group. Thus, predicting the malignant potential and establishing treatment policies should not rely only on the most predominant pattern. Also, imaging parameters of higher non-contrast CT value and higher SUVmax value are associated with non-predominant but high-grade histologic pattern.

Abstract

Background: Prognostic considerations for non-predominant patterns are necessary because most lung adenocarcinomas (ADCs) have a mixed histologic pattern, and the spectrum of actual prognosis varies widely even among lung ADCs with the same most predominant pattern. We aimed to identify prognostic stratification by second most predominant pattern of lung ADC and to more accurately assess prognostic factors with CT imaging analysis, particularly enhancing non-predominant but high-grade pattern. Methods: In this prospective study, patients with early-stage lung ADC undergoing curative surgery underwent preoperative dual-energy CT (DECT) and positron emission tomography (PET)/CT. Histopathology of ADC, the most predominant and second most predominant histologic patterns, and preoperative imaging parameters were assessed and correlated with patient survival. Results: Among the 290 lung ADCs included in the study, 231 (79.7%) were mixed-pathologic pattern. When the most predominant histologic pattern was intermediate-grade, survival curves were significantly different among the three second most predominant subgroups (p = 0.004; low, lepidic; intermediate, acinar and papillary; high, micropapillary and solid). When the second most predominant pattern was high-grade, recurrence risk increased by 4.2-fold compared with the low-grade group (p = 0.005). To predict a non-predominant but high-grade pattern, the non-contrast CT value of tumor was meaningful with a lower HU value associated with the histologic combination of lower grade (low-grade as most predominant and intermediate-grade as second most predominant pattern, OR = 6.15, p = 0.005; intermediate-grade as most predominant and high-grade as second most predominant pattern, OR = 0.10, p = 0.033). SUVmax of the tumor was associated with the non-predominant but high-grade pattern, especially in the histologic combination of intermediate-high grade (OR = 1.14, p = 0.012). Conclusions: The second most predominant histologic pattern can stratify lung ADC patients according to prognosis. Thus, predicting the malignant potential and establishing treatment policies should not rely only on the most predominant pattern. Moreover, imaging parameters of non-contrast CT value and SUVmax could be useful in predicting a non-predominant but high-grade histologic pattern.

SUVmax of 18FDG PET/CT Predicts Histological Grade of Lung Adenocarcinoma

OBJECTIVES

The relationship between the ¹⁸FDG PET-CT maximum standard uptake value (SUVmax) and the type of lung adenocarcinoma is still not established. The aim of this study was to investigate the relationship between SUVmax value and histological grade and pathological subtype of lung adenocarcinoma, and to determine the optimum SUVmax cutoffs for distinguishing different histological grades.

MATERIALS AND METHODS

The data of 618 lung adenocarcinoma patients were retrospectively analyzed. The relationship between SUVmax measured on preoperative ¹⁸FDG-PET-CT and the histological grade and pathological subtype was examined. The Kruskal-Wallis test was used to compare differences among groups, and the Bonferroni-Dunn test for pairwise comparison among groups. ROC analysis was applied to determine the optimal cut-off values for distinguishing different groups. In addition, the cut-off value was verified in an independent cohort of 85 consecutive lung adenocarcinoma cases.

RESULTS

The SUVmax was significantly different between the low, intermediate, and high-grade groups(p < .001). SUVmax value increased with increase in the degree of malignancy. The optimal cut-off value for identifying low-grade tumors was 2.01 (sensitivity 90.4%, specificity 86.9%, area under the curve [AUC] = 0.928, 95% confidence interval: 0.91-0.95; p < .001). The optimal cutoff SUVmax value for identifying high-grade tumors was 7.41 (sensitivity 79.8%, specificity 73.5%, AUC = 0.830, 95% confidence interval: 0.79-0.87; p < .001). The validation experiment showed that the coincidence rate was 88.89% in the low-level group, 64.15% in the middle-level group, and 78.57% in the high-level group.

CONCLUSION

SUVmax can be used to predict pathological subtype and histological grade of lung adenocarcinoma. Thus, ¹⁸FDG PET-CT can serve as a noninvasive tool for precise diagnosis and help in the preoperative formulation of patient-specific treatment strategies.

Value of 18F-FDG PET/CT-Based Radiomics Nomogram to Predict Survival Outcomes and Guide Personalized Targeted Therapy in Lung Adenocarcinoma With EGFR Mutations

Objectives

To investigate the development and validation of a radiomics nomogram based on PET/CT for guiding personalized targeted therapy in patients with lung adenocarcinoma mutation(s) in the EGFR gene.

Methods

A cohort of 109 (77/32 in training/validation cohort) consecutive lung adenocarcinoma patients with an EGFR mutation was enrolled in this study. A total of 1672 radiomic features were extracted from PET and CT images, respectively. The least absolute shrinkage and selection operator (LASSO) Cox regression was used to select the radiomic features and construct the radiomics nomogram for the estimation of overall survival (OS), which was then assessed with respect to calibration and clinical usefulness. Patients with an EGFR mutation were divided into high- and low- risk groups according to their nomogram score. The treatment strategy for high- and low-risk groups was analyzed using Kaplan–Meier analysis and a log-rank test.

Results

The C-index of the radiomics nomogram for the prediction of OS in lung adenocarcinoma in patients with an EGFR mutation was 0.840 and 0.803 in the training and validation cohorts, respectively. Distant metastasis [(Hazard ratio, HR),1.80], metabolic tumor volume (MTV, HR, 1.62), and rad score (HR, 17.23) were the independent risk factors for patients with an EGFR mutation. The calibration curve showed that the predicted survival time was remarkably close to the actual time. Decision curve analysis demonstrated that the radiomics nomogram was clinically useful. Targeted therapy for patients with high-risk EGFR mutations attained a greater benefit than other therapies (p < 0.0001), whereas the prognoses of the two therapies were similar in the low-risk group (p = 0.85).

Conclusions

Development and validation of a radiomics nomogram based on PET/CT radiomic features combined with clinicopathological factors may guide targeted therapy for patients with lung adenocarcinoma with EGFR mutations. This is conducive to the advancement of precision medicine.

Tumor volume shrinkage during stereotactic body radiotherapy is related to better prognoses in patients with stage I non-small-cell lung cancer

The purpose of the study was to investigate the association between tumor volume changes during stereotactic body radiation therapy (SBRT) and prognoses in stage I non-small-cell lung cancer (NSCLC). This retrospective review included stage I NSCLC patients in whom SBRT was performed at a total dose of 48.0-50.5 Gy in four or five fractions. The tumor volumes observed on computed tomography (CT) simulation and on the CT performed at the last treatment session using a CT-on-rails system were measured and compared. Then, the tumor volume changes during the SBRT period were measured and assessed for their association with prognoses (overall survival, local control, lymph node metastases and distant metastases). A total of 98 patients with a mean age of 78.6 years were enrolled in the study. The T-stage was T1a in 42%, T1b in 32% and T2a in 26% of the cases. The gross tumor volume (GTV) shrank and increased ≥10% in 23 (23.5%) and 36 (36.7%) of the cases, respectively. The 5-year local control and overall survival rates in the groups with a tumor shrinkage of ≥10% vs the group with a shrinkage of <10% were 94.7 vs 70.8% and 85.4 vs 47.6%, respectively; these differences were significant, with a P-value < 0.05. During a short SBRT period, the tumor shrank or enlarged in a small number of cases. A decrease of ≥10% in the GTV during SBRT was significantly related to better overall survival and local control.

Development and Validation of a Radiomics Nomogram Based on 18F-Fluorodeoxyglucose Positron Emission Tomography/Computed Tomography and Clinicopathological Factors to Predict the Survival Outcomes of Patients With Non-Small Cell Lung Cancer

Purpose: In this study, we developed and validated a radiomics nomogram by combining the radiomic features extracted from ¹⁸F-fluorodeoxyglucose positron emission tomography/computed tomography (¹⁸F-FDG PET/CT) images and clinicopathological factors to evaluate the overall survival (OS) of patients with non-small cell lung cancer (NSCLC). Patients and Methods: A total of 315 consecutive patients with NSCLC (221 in the training cohort and 94 in the validation cohort) were enrolled in this study. A total of 840 radiomic features were extracted from the CT and PET images. Three radiomic scores (rad-scores) were calculated using the least absolute shrinkage and selection operator (LASSO) Cox regression based on subsets of CT, PET, and PET/CT radiomic features. A multivariate Cox regression analysis was performed for each rad-score combined with clinicopathological factors to determine the independent risk factors. The OS nomogram was constructed based on the PET/CT rad-score and independent clinicopathological factors. Validation and calibration were conducted to evaluate the performance of the model in the training and validation cohorts, respectively. Results: A total of 144 (45.71%) women and 171 (54.29%) men with NSCLC were enrolled in this study. The PET/CT rad-score combined with the clinical model had the best C-index (0.776 and 0.789 for the training and validation cohorts, respectively). Distant metastasis, stage, carcinoembryonic antigen (CEA), and targeted therapy were independent risk factors for patients with NSCLC. The validation curve showed that the OS nomogram had a strong predictive power in patients' survival. The calibration curve showed that the predicted survival time was significantly close to the observed one. Conclusion: A radiomic nomogram based on ¹⁸F-FDG PET/CT rad-score and clinicopathological factors had good predictive performance for the survival outcome, offering feasible, and practical guidance for individualized management of patients with NSCLC.

Predictive and Prognostic Role of Metabolic Response in Patients With Stage III NSCLC Treated With Neoadjuvant Chemotherapy

INTRODUCTION

The purpose of this study was to assess the predictive and prognostic role of 18F-fluorodeoxyglucose (18F-FDG) positron emission tomography/computed tomography (PET/CT) in candidates with stage III non-small-cell lung cancer (NSCLC) to neoadjuvant chemotherapy.

PATIENTS AND METHODS

Sixty-six patients with stage III NSCLC treated with induction chemotherapy from March 2013 to December 2017 were retrospectively identified. Response assessment were evaluated according to the Response Evaluation Criteria in Solid Tumors (RECIST) 1.1 and European Organisation for Research and Treatment of Cancer (EORTC) criteria. 18F-FDG PET/CT metabolic parameters were analyzed as absolute values as well as percentage changes (Δ) between 2 consecutive scans, for primary tumor (T) and for regional lymph nodes (N). All clinical variables and metabolic parameters were compared with treatment response and correlated with progression-free survival (PFS) and overall survival (OS), based on a median follow-up of 9.4 months.

RESULTS

Post-induction therapy standardized uptake value (SUV)max_T, SUVmean_T, metabolic tumor volume (MTV_T), and total lesion glycolysis of the tumor (TLG_T) varied significantly between responders and non-responders (6.6 vs. 13.8; P = .001; 4.2 vs. 8.1; P < .001; 6 vs. 17.9; P = .002; and 24.1 vs. 136.3; P < .001, respectively). Likewise, percentage changes (Δ_T) were significantly different between the 2 groups (P < .001). Along with primary tumor, also post-SUVmax_N, post-SUVmean_N, and post-TLG_N (P = .024, P = .015, and P = .024, respectively), as well as all percentage changes (Δ_N) were different between responders and non-responders. RECIST 1.1 and EORTC response classifications were discordant in 27 patients (40.9%; κ = 0.265; P = .003). On multivariate analysis, post-TLG_N was an independent predictor for both PFS and OS, whereas RECIST 1.1 was a predictor only for OS.

CONCLUSIONS

Several metabolic parameters may differentiate responders from non-responders following neoadjuvant chemotherapy in stage III NSCLC. As compared with RECIST 1.1, EORTC seems to be more appropriate for evaluation therapeutic response. Finally, post-TLG_N has significant prognostic information.

Combining fluorine-18 fluorodeoxyglucose positron emission tomography and pathological risk factors to predict postoperative recurrence in stage I lung adenocarcinoma

OBJECTIVE

The aim of this study was to investigate the predictive value of qualitative assessment of tumor fluorine-18 fluorodeoxyglucose (F-FDG) uptake on PET and pathological risk factors for postoperative tumor recurrence in patients with stage I lung adenocarcinoma.

PATIENTS AND METHODS

Eighty-seven patients with stage I lung adenocarcinoma who had undergone F-FDG-PET and sequential surgical treatment without adjuvant chemotherapy were enrolled into this retrospective study. Qualitative assessment visually compared tumor F-FDG uptake with liver uptake. Tumors with one or more risk factors of tumor size of at least 4 cm, poorly differentiated, visceral pleural invasion, and lymphovascular invasion were defined as pathological high-risk tumors.

RESULTS

Patients with pathological high-risk tumors had a significantly (P=0.015) higher standardized uptake value. A multivariable Cox's proportional hazard analysis showed that tumor F-FDG uptake>liver uptake (adjusted hazard ratio: 3.54; 95% confidence interval: 1.36-9.21, P=0.010) and pathological high-risk tumors (adjusted hazard ratio: 2.34; 95% confidence interval: 1.13-4.87, P=0.023) were significant independent predictors of postoperative tumor recurrence. Patients with tumor F-FDG uptake>liver uptake and pathological high-risk tumors had significantly (P=0.001) worse 5-year disease-free survival (38.8%) and significantly (P=0.011) worse overall survival (68.5%).

CONCLUSION

Tumor F-FDG uptake>liver uptake and pathological high-risk tumors were significant independent predictors of postoperative tumor recurrence in stage I lung adenocarcinoma. Combining the two factors improves the prediction of disease-free and overall survivals, which could offer a feasible prediction model for clinically recommending adjuvant chemotherapy.

18F-fluorodeoxyglucose positron emission tomography/computed tomography in the evaluation of clinically node-negative non-small cell lung cancer

One in four non-small cell lung cancer (NSCLC) patients are diagnosed at an early-stage. Following the results of the National Lung Screening Trial that demonstrated a survival benefit for low-dose computed tomography screening in high-risk patients, the incidence of early-stage NSCLC is expected to increase. Use of 18F-fluorodeoxyglucose positron emission tomography/computed tomography during initial diagnosis of these early-stage lesions has been increasing. Traditionally, positron emission tomography/computed tomography scans have been utilized for mediastinal nodal staging and to rule out distant metastases in suspected early-stage NSCLC. In clinically node-negative NSCLC, the use of sublobar resection and selective lymph node dissection has been increasing as a therapeutic option. The higher rate of locoregional recurrences after limited resection and the significant incidence of occult lymph node metastases underscores the need to further stratify clinically node-negative NSCLC in order to select patients for limited resection versus lobectomy with complete mediastinal lymph node dissection. In this report, we review the published data, and discuss the significance and potential role of 18F-fluorodeoxyglucose positron emission tomography/computed tomography evaluation for clinically node-negative NSCLC. Consequently, the literature review demonstrates that maximum standardized uptake value is a predictive factor for occult nodal metastasis with an accuracy of 55-77%. In addition, maximum standardized uptake value is a predictor for worse overall, as well as disease-free, survival.

Metabolic positron emission tomography parameters predict failure patterns in early non-small-cell lung cancer treated with stereotactic body radiation therapy: a single institution experience

Objective

The prognostic value of metabolic parameters using 18F-fluorodeoxyglucose positron emission tomography/computed tomography (FDG PET/CT) has not been established for early non-small cell lung cancer (NSCLC). Accordingly, the authors investigated the prognostic value of metabolic parameters in terms of failure patterns in patients with early NSCLC who underwent stereotactic body radiation therapy (SBRT).

Methods

Data from 35 patients with Stage I NSCLC who underwent SBRT using CyberKnife and received pretreatment FDG PET/CT between 2008 and 2016 were retrospectively reviewed. Maximum standardized uptake value (SUVmax), metabolic tumor volume, and total lesion glycolysis were measured. The significance of these parameters with regard to failure patterns was assessed.

Results

The median follow-up was 23 months for all patients and 34 months for living patients. Ten patients experienced recurrence: three local failures, five regional failures (RF), and eight distant failures (DF). Three-year local, regional and distant control rates were 96.7%, 86.4% and 71.1%, respectively. High SUVmax (<9 vs. ≥9) was an independent predictive factor associated with increased RF (P = 0.027) and DF (P = 0.008). Furthermore, SUVmax was indicative of both progression-free (P = 0.015) and overall (P = 0.034) survival.

Conclusions

High SUVmax was a significant metabolic parameter associated with increased RF and DF in patients with early NSCLC who received SBRT, having a high propensity for dissemination. These results suggest that adjuvant treatment in conjunction with SBRT may be considered in patients with early NSCLC and high SUVmax.

Effect of PET/CT standardized uptake values on complete response to treatment before definitive chemoradiotherapy in stage III non-small cell lung cancer

PURPOSE

The standard treatment for patients with stage III non-small cell lung cancer (NSCLC), unsuitable for resection and with good performance, is definitive radiotherapy with cisplatin-based chemotherapy. Our aim is to evaluate the effect of the maximum value of standardized uptake values (SUVmax) of the primary tumor in positron emission tomography-computed tomography (PET/CT) before treatment on complete response (CR) and overall survival.

METHODS

The data of 73 stage III NSCLC patients treated with concurrent definitive chemoradiotherapy (CRT) between 2008 and 2017 and had PET/CT staging in the pretreatment period were evaluated. ROC curve analysis was performed to determine the ideal cut-off value of pretreatment SUVmax to predict CR.

RESULTS

Median age was 58 years (range 27-83 years) and 66 patients were male (90.4%). Median follow-up time was 18 months (range 3-98 months); median survival was 23 months. 1-year overall survival (OS) rate and 5-year OS rate were 72 and 19%, respectively. Median progression-free survival (PFS) was 9 months; 1-year PFS rate and 5-year PFS rate were 38 and 19%, respectively. The ideal cut-off value of pretreatment SUVmax that predicted the complete response of CRT was 12 in the ROC analysis [AUC 0.699 (0.550-0.833)/P < 0.01] with a sensitivity of 83%, and specificity of 55%. In patients with SUVmax < 12, CR rate was 60%, while, in patients with SUV ≥ 12, it was only 19% (P = 0.002). Median OS was 26 months in patients with pretreatment SUVmax < 12, and 21 months in patients with SUVmax ≥ 12 (HR = 2.93; 95% CI 17.24-28.75; P = 0.087). CR rate of the whole patient population was 26%, and it was the only factor that showed a significant benefit on survival in both univariate and multivariate analyses.

CONCLUSION

Pretreatment SUVmax of the primary tumor in PET/CT may predict CR in stage III NSCLC patients who were treated with definitive CRT. Having clinical CR is the only positive predictive factor for prolonged survival.

18F-FDG PET intensity correlates with a hypoxic gene signature and other oncogenic abnormalities in operable non-small cell lung cancer

BACKGROUND

18F-fluorodeoxyglucose positron emission tomography (FDG-PET) is critical for staging non-small-cell lung cancer (NSCLC). While PET intensity carries prognostic significance, the genetic abnormalities associated with increased intensity remain unspecified.

METHODS

NSCLC samples (N = 34) from 1999 to 2011 for which PET data were available were identified from a prospectively collected tumor bank. PET intensity was classified as mild, moderate, or intense based on SUVmax measurement or radiology report. Associations between genome-wide expression (RNAseq) and PET intensity were determined. Associations with overall survival were then validated in two external NSCLC cohorts.

RESULTS

Overall survival was significantly worse in patients with PET-intense (N = 11) versus mild (N = 10) tumors (p = 0.039). Glycolytic gene expression patterns were markedly similar between intense and mild tumors. Gene ontology analysis demonstrated significant enhancement of cell-cycle and proliferative processes in FDG-intense tumors (p<0.001). Gene set enrichment analysis (GSEA) suggested associations between PET-intensity and canonical oncogenic signaling pathways including MYC, NF-κB, and HIF-1. Using an external cohort of 25 tumors with PET and genomic profiling data, common genes and gene sets were validated for additional study (P<0.05). Of these common gene sets, 20% were associated with hypoxia or HIF-1 signaling. While HIF-1 expression did not correlate with poor survival in the NSCLC validation cohort (N = 442), established targets of hypoxia signaling (PLAUR, ADM, CA9) were significantly associated with poor overall survival.

CONCLUSIONS

PET-intensity is associated with a variety of oncogenic alterations in operable NSCLC. Adjuvant targeting of these pathways may improve survival among patients with PET-intense tumors.

The role of metabolic tumor volume (MTV) measured by [18F] FDG PET/CT in predicting EGFR gene mutation status in non-small cell lung cancer

Many noninvasive methods have been explored to determine the mutation status of the epidermal growth factor receptor (EGFR) gene, which is important for individualized treatment of non-small cell lung cancer (NSCLC). We evaluated whether metabolic tumor volume (MTV), a parameter measured by [18F] fluorodeoxyglucose positron emission tomography/computed tomography (PET/CT) might help predict EGFR mutation status in NSCLC. Overall, 87 patients who underwent EGFR genotyping and pretreatment PET/CT between January 2013 and September 2016 were reviewed. Clinicopathologic characteristics and metabolic parameters including MTV were evaluated. Univariate and multivariate analyses were used to assess the independent variables that predict mutation status to create prediction models. Forty-one patients (41/87) were identified as having EGFR mutations. The multivariate analysis showed that patients with lower MTV (MTV≤11.0 cm3, p=0.001) who were non-smokers (p=0.037) and had a peripheral tumor location (p=0.033) were more likely to have EGFR mutations. Prediction models using these criteria for EGFR mutation yielded a high AUC (0.805, 95% CI 0.712–0.899), which suggests that the analysis had good discrimination. In conclusion, NSCLC patients with EGFR mutations showed significantly lower MTV than patients with wild-type EGFR. Prediction models based on MTV and clinicopathologic characteristics could provide more information for the identification of EGFR mutations.

Prognostic Value of 18F-Fluorodeoxyglucose PET/Computed Tomography in Non-Small-Cell Lung Cancer

Non-small cell lung cancer (NSCLC) is a leading cause of cancer-related death with a poor prognosis. Numerous factors contribute to treatment outcome. 18F-fluorodeoxyglucose (FDG) uptake reflects tumor metabolic activity and is an important prognosticator in patients with NSCLC. Volume-based FDG-PET parameters reflect the metabolic status of a malignancy more accurately than maximum standardized uptake value and thus are better prognostic markers in lung cancer. FDG-avid tumor burden parameters may help clinicians to predict treatment outcomes before and during therapy so that treatment can be adjusted to achieve the best possible outcomes while avoiding side effects.

Maximum standardized uptake value on FDG-PET predicts survival in stage I non-small cell lung cancer following carbon ion radiotherapy

The present study (University Hospital Medical Information Network study no. UMIN000003797) aimed to evaluate whether the maximum standardized uptake value (SUV_max) of pretreatment ¹⁸F-fluorodeoxyglucose-positron emission tomography (FDG-PET) is prognostic factor for stage I non-small cell lung cancer (NSCLC) treated with carbon ion radiotherapy (C-ion RT). Patients treated between June 2010 and June 2013 at Gunma University Heavy Ion Medical Center (Maebashi, Japan) on a prospective protocol were included in the present study. Patients with T1a-b and T2a NSCLC were treated with C-ion RT at a dose of 52.8 Gy [relative biological effectiveness (RBE)] and 60.0 Gy (RBE), respectively, in four fractions. Prior to treatment, all patients underwent FDG-PET, in which the SUV_max of primary tumors was evaluated. Local control, progression-free survival (PFS), and overall survival (OS) were calculated. A total of 45 patients were analyzed and the median follow-up period was 28.9 months. The 2-year local control, PFS and OS rates for all patients were 93, 78 and 89%, respectively. The mean SUV_max of primary tumors was 5.5, and patients were divided into higher (≥5.5) and lower (<5.5) SUV_max groups. The 2-year PFS rates were 61 and 89% for the higher and lower SUV_max groups, respectively (P=0.01), and the 2-year OS rates for the higher and lower SUV_max groups were 76 and 96%, respectively (P=0.01). The higher SUV_max group exhibited a significantly worse PFS and OS compared with the lower SUV_max group; however, the SUV_max was not associated with the local control rate. In total, 2 patients (4%) experienced grade 2 or 3 radiation pneumonitis, with their symptoms improved through conservative treatment. No patients experienced any grade 4 or 5 toxicities. The results of the present study indicate that pretreatment SUV_max is a prognostic indicator for outcomes in patients with stage I NSCLC treated with C-ion RT.

Relation between tumor FDG uptake and hematologic prognostic indicators in stage I lung cancer patients following curative resection

Hematologic parameters of systemic inflammation are receiving attention as promising prognostic indicators in cancer patients. Here, we investigated the relation and compared the prognostic values of circulating blood cell-based parameters and tumor F-fluoro-2-deoxyglucose (FDG) uptake in patients with stage I nonsmall cell lung cancers (NSCLC).Subjects were 1034 patients with newly diagnosed stage I NSCLC who underwent FDG positron emission tomography/computed tomography (PET/CT) followed by curative resection. Total white blood cell (WBC) count, absolute neutrophil, lymphocyte and platelet counts, neutrophil-to-lymphocyte ratio (NLR), and platelet-to-lymphocyte ratio (PLR) were obtained. Tumor FDG uptake was measured as SUVmax.WBC, neutrophil and lymphocyte counts, and NLR demonstrated weak but significant correlation to tumor SUVmax. Using the upper quartile as cutoff, patients with high tumor SUVmax had significantly higher WBC, neutrophil and lymphocyte counts, and greater NLR. There were 144 recurrences (13.9%) over a median follow-up of 29.5 months. On Cox proportional hazards regression analysis, WBC count, tumor SUVmax, age, gender, smoking, cell type, and tumor stage were significant univariate prognostic factors. On multivariate analysis, high tumor SUVmax (HR = 2.22; 95% CI, 1.52-3.25; P < 0.001), tumor stage 1B (HR = 2.11; 95% CI, 1.47-3.01; P < 0.001), and old age (HR = 1.03; 95% CI, 1.01-1.05; P = 0.002) were significant independent predictors of poor survival. Finally, high tumor SUVmax remained a significant predictor of prognosis in both low and WBC count groups.Circulating blood counts showed significant correlation to tumor FDG uptake in early stage NSCLC. WBC count was a significant univariate variable, but tumor FDG uptake was a superior and independent predictor of outcome. Hence, tumor FDG uptake effectively stratified prognosis in patients with low as well as high WBC count.

Molecular Imaging and Precision Medicine in Lung Cancer

Precision medicine allows tailoring of preventive or therapeutic interventions to avoid the expense and toxicity of futile treatment given to those who will not respond. Lung cancer is a heterogeneous disease functionally and morphologically. PET is a sensitive molecular imaging technique with a major role in the precision medicine algorithm of patients with lung cancer. It contributes to the precision medicine of lung neoplasia by interrogating tumor heterogeneity throughout the body. It provides anatomofunctional insight during diagnosis, staging, and restaging of the disease. It is a biomarker of tumoral heterogeneity that helps direct selection of the most appropriate treatment, the prediction of early response to cytotoxic and cytostatic therapies, and is a prognostic biomarker in patients with lung cancer.

FDG Uptake on Positron Emission Tomography Correlates with Survival and Time to Recurrence in Patients with Stage I Non-Small-Cell Lung Cancer

INTRODUCTION

Patients with stage I non-small-cell lung cancer (NSCLC) have a wide variation in outcomes, most likely because there are undetected metastases at presentation. We retrospectively reviewed patients with early stage lung cancer to determine if FDG uptake of the primary tumor as measured on positron emission tomography (PET) at the time of diagnosis was associated with overall survival (OS) or time to recurrence (TTR).

METHODS

We reviewed the Tumor Registry at our institution and identified 336 consecutive patients diagnosed with stage I NSCLC over a 5-year period who underwent an FDG-PET/computed tomography within 90 days before surgery. Kaplan-Meier curves were used to describe the survival and TTR experience within subgroups defined by PET maximum standardized uptake value (SUVmax). Cox proportional hazards model was used to assess the impact of PET SUVmax as a continuous variable on OS and TTR. Logistic regression was used to analyze the effect of SUVmax on dichotomized outcomes.

RESULTS

Three hundred thirty-six consecutive patients (176 women and 160 men) with stage I NSCLC were retrospectively reviewed. Mean SUVmax was 9.2 ± 6.9 (range 0.6-30.3). The hazard or risk of dying and recurrence increased significantly as SUVmax increased (p = 0.0008 and 0.024, respectively).

CONCLUSIONS

Preoperative FDG uptake in the primary tumor in patients with stage I disease is associated with OS and TTR. This may be useful in identifying early stage patients who may benefit from more aggressive therapy after surgical resection.

The role of new PET tracers for lung cancer

18F-fluorodeoxyglucose (18F-FDG) positron emission tomography-computed tomography (PET/CT) is established for characterising indeterminate pulmonary nodules and staging lung cancer where there is curative intent. Whilst a sensitive technique, specificity for characterising lung cancer is limited. There is recognition that evaluation of other aspects of abnormal cancer biology in addition to glucose metabolism may be more helpful in characterising tumours and predicting response to novel targeted cancer therapeutics. Therefore, efforts have been made to develop and evaluate new radiopharmaceuticals in order to improve the sensitivity and specificity of PET imaging in lung cancer with regards to characterisation, treatment stratification and therapeutic monitoring. 18F-fluorothymidine (18F-FLT) is a marker of cellular proliferation. It shows a lower accumulation in tumours than 18F-FDG as it only accumulates in the cells that are in the S phase of growth and demonstrates a low sensitivity for nodal staging. Its main role is in evaluating treatment response. Methionine is an essential amino acid. 11C-methionine is more specific and sensitive than 18F-FDG in differentiating benign and malignant thoracic nodules. 18Ffluoromisonidazole (18F-FMISO) is used for imaging tumour hypoxia. Tumour response to treatment is significantly related to the level of tumour oxygenation. Angiogenesis is the process by which new blood vessels are formed in tumours and is involved in tumour growth and metastatic tumour spread and is a therapeutic target. Most clinical studies have focused on targeted integrin PET imaging of which αvβ3 integrin is the most extensively investigated. It is upregulated on activated endothelial cells in association with tumour angiogenesis. Neuroendocrine tumour tracers, particularly 68Ga-DOTA-peptides, have an established role in imaging of carcinoid tumours. Whilst most of these tracers have predominantly been used in the research environment, they offer exciting opportunities for improving staging, characterisation, stratification and response assessment in an era of increased personalised therapy in lung cancer.

Prognostic Value of 18F-FDG PET/CT in Surgical Non-Small Cell Lung Cancer: A Meta-Analysis

Background

The identification of surgical non-small cell lung cancer (NSCLC) patients with poor prognosis is a priority in clinical oncology because of their high 5-year mortality. This meta-analysis explored the prognostic value of maximal standardized uptake value (SUV_max), metabolic tumor volume (MTV) and total lesion glycolysis (TLG) on disease-free survival (DFS) and overall survival (OS) in surgical NSCLC patients.

Materials and Methods

MEDLINE, EMBASE and Cochrane Libraries were systematically searched until August 1, 2015. Prospective or retrospective studies that evaluated the prognostic roles of preoperative 18F-FDG PET/CT with complete DFS and OS data in surgical NSCLC patients were included. The impact of SUV_max, MTV or TLG on survival was measured using hazard ratios (HR). Sub-group analyses were performed based on disease stage, pathological classification, surgery only and cut-off values.

Results

Thirty-six studies comprised of 5807 patients were included. The combined HRs for DFS were 2.74 (95%CI 2.33–3.24, unadjusted) and 2.43 (95%CI: 1.76–3.36, adjusted) for SUV_max, 2.27 (95%CI 1.77–2.90, unadjusted) and 2.49 (95%CI 1.23–5.04, adjusted) for MTV, and 2.46 (95%CI 1.91–3.17, unadjusted) and 2.97 (95%CI 1.68–5.28, adjusted) for TLG. The pooled HRs for OS were 2.54 (95%CI 1.86–3.49, unadjusted) and 1.52 (95%CI 1.16–2.00, adjusted) for SUV_max, 2.07 (95%CI 1.16–3.69, unadjusted) and 1.91 (95%CI 1.13–3.22, adjusted) for MTV, and 2.47 (95%CI 1.38–4.43, unadjusted) and 1.94 (95%CI 1.12–3.33, adjusted) for TLG. Begg’s test detected publication bias, the trim and fill procedure was performed, and similar HRs were obtained. The prognostic role of SUV_max, MTV and TLG remained similar in the sub-group analyses.

Conclusions

High values of SUV_max, MTV and TLG predicted a higher risk of recurrence or death in patients with surgical NSCLC. We suggest the use of FDG PET/CT to select patients who are at high risk of disease recurrence or death and may benefit from aggressive treatments.

Primary tumour standardised uptake value is prognostic in nonsmall cell lung cancer: a multivariate pooled analysis of individual data

(18)F-fluoro-2-deoxy-d-glucose positron emission tomography (PET) complements conventional imaging for diagnosing and staging lung cancer. Two literature-based meta-analyses suggest that maximum standardised uptake value (SUVmax) on PET has univariate prognostic value in nonsmall cell lung cancer (NSCLC). We analysed individual data pooled from 12 studies to assess the independent prognostic value of binary SUVmax for overall survival.After searching the published literature and identifying unpublished data, study coordinators were contacted and requested to provide data on individual patients. Cox regression models stratified for study were used.Data were collected for 1526 patients (median age 64 years, 60% male, 34% squamous cell carcinoma, 47% adenocarcinoma, 58% stage I-II). The combined univariate hazard ratio for SUVmax was 1.43 (95% CI 1.22-1.66) and nearly identical if the SUV threshold was calculated stratifying for histology. Multivariate analysis of patients with stage I-III disease identified age, stage, tumour size and receipt of surgery as independent prognostic factors; adding SUV (HR 1.58, 95% CI 1.27-1.96) improved the model significantly. The only detected interaction was between SUV and stage IV disease.SUV seems to have independent prognostic value in stage I-III NSCLC, for squamous cell carcinoma and for adenocarcinoma.

FDG-PET maximum standardized uptake value is prognostic for recurrence and survival after stereotactic body radiotherapy for non-small cell lung cancer

OBJECTIVES

Glucose metabolic activity measured by [(18)F]-fluoro-2-deoxy-glucose positron emission tomography (FDG-PET) has shown prognostic value in multiple malignancies, but results are often confounded by the inclusion of patients with various disease stages and undergoing various therapies. This study was designed to evaluate the prognostic value of tumor FDG uptake quantified by maximum standardized uptake value (SUVmax) in a large group of early-stage non-small cell lung cancer (NSCLC) patients treated with stereotactic body radiotherapy (SBRT) using consistent treatment techniques.

MATERIALS AND METHODS

Two hundred nineteen lesions in 211 patients treated with definitive SBRT for stage I NSCLC were analyzed after a median follow-up of 25.2 months. Cox regression was used to determine associations between SUVmax and overall survival (OS), disease-specific survival (DSS), and freedom from local recurrence (FFLR) or distant metastasis (FFDM).

RESULTS

SUVmax >3.0 was associated with worse OS (p<0.001), FFLR (p=0.003) and FFDM (p=0.003). On multivariate analysis, OS was associated with SUVmax (HR 1.89, p=0.03), gross tumor volume (GTV) (HR 1.94, p=0.005) and Karnofsky performance status (KPS) (HR 0.51, p=0.008). DSS was associated only with SUVmax (HR 2.58, p=0.04). Both LR (HR 11.47, p=0.02) and DM (HR 3.75, p=0.006) were also associated with higher SUVmax.

CONCLUSION

In a large patient population, SUVmax >3.0 was associated with worse survival and a greater propensity for local recurrence and distant metastasis after SBRT for NSCLC.

Predictive value of 18F-FDG PET and CT morphologic features for recurrence in pathological stage IA non-small cell lung cancer

Patients with pathological stage IA non-small cell lung cancer (NSCLC) may relapse despite complete surgical resection without lymphovascular invasion. A method of selecting a high-risk group for adjuvant therapy is necessary. The aim of this study was to assess the predictive value of F-fluorodeoxyglucose (FDG) uptake and the morphologic features of computed tomography (CT) for recurrence in pathological stage IA NSCLC.One hundred forty-five patients with pathological stage IA NSCLC who underwent pretreatment with FDG positron emission tomography and CT evaluations were retrospectively enrolled. The associations among tumor recurrence and patient characteristics, maximal standard uptake value (SUVmax) of primary tumors, and CT imaging features were investigated using univariate and multivariate analyses. A receiver operating characteristic (ROC) curve analysis was performed to quantify the predictive value of these factors.Tumor recurrence developed in 21 (14.5%) of the 145 patients, and the 5-year recurrence-free survival rate was 77%. The univariate analysis demonstrated that SUVmax, the grade of histological differentiation, tumor size, and the presence of bronchovascular bundle thickening were significant predictive factors (P < 0.05). A higher SUVmax (≥2.5) (P = 0.021), a lower ground-glass opacity ratio (≤17%) (P = 0.014), and the presence of bronchovascular bundle thickening (P = 0.003) were independent predictive factors of tumor recurrence in the multivariate analysis. The use of this predictive model yielded a greater area under the ROC curve (0.877), which suggests good discrimination.The combined evaluation of FDG uptake and CT morphologic features may be helpful in the prediction of recurrence in patients with pathological stage IA NSCLC and in the stratification of a high-risk group for postoperative adjuvant therapy or prospective clinical trials.

PET-based radiation therapy planning

In this review, we review the literature on the use of PET in radiation treatment planning, with an emphasis on describing our institutional methodology (where applicable). This discussion is intended to provide other radiation oncologists with methodological details on the use of PET imaging for treatment planning in radiation oncology, or other oncologists with an introduction to the use of PET in planning radiation therapy.

Prognostic Value of Fluoro-D-glucose Uptake of Primary Tumor and Metastatic Lesions in Advanced Nonsmall Cell Lung Cancer

To assess the prognostic value of maximum standardized uptake value (maxSUV) of the primary tumor (maxSUVpt), maxSUV of whole-body tumors (maxSUVwb) and sum of maximum standardized uptake value (sumaxSUV) measured by the sum of maxSUVs of the primary tumor, metastatic lymph nodes, and metastatic lesions per each organ on fluoro-D-glucose-positron emission tomography/computed tomography in advanced non-small cell lung cancer (NSCLC). Eighty-three patients (49 male, 34 female) with advanced NSCLC were enrolled. Seventeen patients had Stage IIIA, 21 Stage IIIB, and 45 Stage IV. maxSUVpt, maxSUVwb, sumaxSUV, age, gender, tumor-cell type, T stage, N stage, overall stage, primary tumor size, and specific treatment were analyzed for correlation with overall survival. Median follow-up duration was 13 months. Fifty patients were dead during a median follow-up time of 11 months and 33 patients were alive with a median time of 15 months. Univariate analysis revealed that overall survival was significantly correlated with sumaxSUV (≥35 vs. <35, P = 0.004), T stage (T4 vs. T1-T3, P = 0.025), overall stage (IV vs. III, P = 0.002), gender (male vs. female, P = 0.029) and specific treatment (no vs. yes, P = 0.011). maxSUVpt and maxSUVwb were not correlated with overall survival with P value of 0.139 and 0.168, respectively. Multivariate analysis identified sumaxSUV, T stage, gender, and specific treatment as independent prognostic indicators. Patients with a sumaxSUV of ≥35 were 1.921 times more likely to die than those with a sumaxSUV of < 35 (P = 0.047). Median survival time was 14 months for patients with sumaxSUV ≥ 35 compared with 20 months for those with sumaxSUV < 35. In patients with metastatic NSCLC, sumaxSUV with cut-off of 35 was much more significant for survival prognosis (P = 0.021). sumaxSUV is a new prognostic measure, independent of tumor stage, gender, and specific treatment in advanced NSCLC. sumaxSUV may be better than maxSUVpt and maxSUVwb in prediction of survival. A large prospective cohort study is necessary to validate these results.

Pretreatment [18F]-fluoro-2-deoxy-glucose positron emission tomography maximum standardized uptake value as predictor of distant metastasis in early-stage non-small cell lung cancer treated with definitive radiation therapy: rethinking the role of positron emission tomography in personalizing treatment based on risk status

PURPOSE

The aim of this study was to determine whether the preradiation maximum standardized uptake value (SUVmax) of the primary tumor for [(18)F]-fluoro-2-deoxy-glucose positron emission tomography (FDG-PET) has a prognostic significance in patients with Stage T1 or T2N0 non-small cell lung cancer (NSCLC) treated with curative radiation therapy, whether conventional or stereotactic body radiation therapy (SBRT).

METHODS AND MATERIALS

Between January 2007 and December 2011, a total of 163 patients (180 tumors) with medically inoperable histologically proven Stage T1 or T2N0 NSCLC and treated with radiation therapy (both conventional and SBRT) were entered in a research ethics board approved database. All patients received pretreatment FDG-PET / computed tomography (CT) at 1 institution with consistent acquisition technique. The medical records and radiologic images of these patients were analyzed.

RESULTS

The overall survival at 2 years and 3 years for the whole group was 76% and 67%, respectively. The mean and median SUVmax were 8.1 and 7, respectively. Progression-free survival at 2 years with SUVmax <7 was better than that of the patients with tumor SUVmax ≥7 (67% vs 51%; P=.0096). Tumors with SUVmax ≥7 were associated with a worse regional recurrence-free survival and distant metastasis-free survival. In the multivariate analysis, SUVmax ≥7 was an independent prognostic factor for distant metastasis-free survival.

CONCLUSION

In early-stage NSCLC managed with radiation alone, patients with SUVmax ≥7 on FDG-PET / CT scan have poorer outcomes and high risk of progression, possibly because of aggressive biology. There is a potential role for adjuvant therapies for these high-risk patients with intent to improve outcomes.

Risk factors of postoperative recurrences in patients with clinical stage I NSCLC

Background

Despite advances in radiation therapy, chemotherapy, and newly developed molecular targeting therapies, long-term survival after resection for patients with NSCLC remains less than 50%. We investigated factors predicting postoperative locoregional recurrences and distant metastases in patients with clinical stage I non-small-cell lung cancer (NSCLC) after surgical resection.

Methods

All patients with clinical stage I NSCLC, who underwent surgical resection between January 2002 and June 2006, were reviewed retrospectively. Multiple logistic regression analyses were used to identify independent risk factors for patients with locoregional recurrences and distant metastases.

Results

A total of 261 patients were eligible. Overall survival was significant related to locoregional recurrences (P = 0.03) and distant metastases (P <0.001). There were significant differences of locoregional recurrence in tumor differentiation (P = 0.032) and advanced pathological stage (P = 0.002). In the group of distant metastases, there were significant differences in tumor differentiation (P = 0.035), lymphovascular space invasion (P = 0.031). Among the relationship between pattern of distant metastasis and clinicopathologic variables in patients with clinical stage I NSCLC, SUVmax (P = 0.02) and tumor size (P = 0.001) had significant differences. According to multiple logistic regression analysis, tumor differentiation is the only risk factor of postoperative outcome for locoregional recurrence and serum CEA (>3.5 ng/mL) is the predictor of distant metastasis.

Conclusions

Tumor differentiation and serum CEA were predictors of postoperative relapse for clinical stage I NSCLC after surgical resection. Risk factors of postoperative recurrence in patients with clinical stage I NSCLC may enable us to optimize the patient selection for postoperative adjuvant therapies or neoadjuvant treatment before surgery.

Pretreatment maximum standardized uptake value on 18F-fluorodeoxyglucose positron emission tomography is a predictor of outcome for stage I non-small cell lung cancer after stereotactic body radiotherapy

AIMS

Stereotactic body radiotherapy (SBRT) is commonly considered an important treatment option for patients with stage I non-small cell lung cancer (NSCLC) who have contraindications for surgery or refuse surgery. Many studies have reported that the maximum standardized uptake value (SUVmax) on 18F-fluorodeoxyglucose positron emission tomography (FDG-PET) of the primary tumor has prognostic value for resected NSCLC. The purpose of this study was to determine whether SUVmax is a predictor of disease-free survival (DFS) in patients with stage I NSCLC after SBRT.

METHODS

In all patients, the diagnosis was pathologically or cytologically confirmed. The prescription dose was 48 Gy in four fractions at the isocenter. FDG-PET was performed before SBRT.

RESULTS

Twenty-nine patients were enrolled in this study. The median follow-up period was 14 months (range, 2-56 months). Regional lymph node metastasis and distant metastasis were observed in 5 (17%) and 2 (7%), respectively. The median SUVmax was 5.6 (range, 2.2-22.0). DFS at 2 years was significantly different between the low SUVmax (<8.0) and high SUVmax (≥8.0) groups (85 versus 17%). In univariate analysis, SUVmax and gross tumor volume were significantly correlated with DFS. Multivariate analysis included variables with P-values <0.20 and showed that only SUVmax was significantly correlated with DFS.

CONCLUSION

Pretreatment SUVmax on FDG-PET predicted the DFS in patients with stage I NSCLC after SBRT.

Prediction of 2 years-survival in patients with stage I and II non-small cell lung cancer utilizing (18)F-FDG PET/CT SUV quantification

BACKGROUND

The purpose of the study was to evaluate the correlation between the maximum standardized uptake value (SUVmax), size of primary lung lesion, disease-free survival (DFS) and overall survival (OS) in patients with stage I and II non-small cell lung cancer (NSCLC) in 2 years follow-up.

PATIENTS AND METHODS

Forty-nine patients with stage I-II NSCLC were included in this study. Pre-surgical 2-deoxy-2-[18F]fluoro-D-glucose positron-emission tomography ((18)F-FDG PET/CT) study was performed for all patients. The relationship between SUVmax, tumour size and clinical outcome was measured. The cut-off value for SUVmax and tumour size with the best prognostic significance, probability of DFS and the correlation between SUVmax and the response to therapy were calculated.

RESULTS

There was a statistically significant correlation between SUVmax and DFS (p = 0.029). The optimal cut-offs were 9.00 for SUVmax (p = 0.0013) and 30mm for tumour size (p = 0.0028). Patients with SUVmax > 9 and primary lesion size > 30 mm had an expected 2years-DFS of 37.5%, while this rose to 90% if the tumour was <30 mm and/or SUVmax was <9.

CONCLUSIONS

In stage I-II, SUVmax and tumour size might be helpful to identify the subgroup of patients with high chance for recurrence.

Guidelines for the role of FDG-PET/CT in lung cancer management

Fluoro-2-deoxy-d-glucose (FDG)-positron emission tomography (PET) and PET/computed tomography (FDG-PET/CT) is regarded as a standard of care in the management of non-small-cell lung carcinoma (NSCLC) and is a useful adjunct in the characterization of indeterminate solitary lung nodules (SLN), and pre-treatment staging of NSCLC, notably mediastinal nodal staging and detection of remote metastases. FDG-PET/CT has the ability to assess locoregional lymph node spread more precisely than CT, to detect metastatic lesions that would have been missed on conventional imaging or are located in difficult areas, and to help in the differentiation of lesions that are equivocal after conventional imaging. Increasingly FDG-PET/CT is employed in radiotherapy planning, prediction of prognosis in terms of tumor response to neo-adjuvant, radiation and chemotherapy treatment. Evidence is accumulating of usefulness of PET/CT in small cell lung cancer.

High SUVmax on FDG-PET indicates pleomorphic subtype in epithelioid malignant pleural mesothelioma: supportive evidence to reclassify pleomorphic as nonepithelioid histology

BACKGROUND

We have recently proposed to reclassify the pleomorphic subtype of epithelioid malignant pleural mesothelioma (MPM) as nonepithelioid (biphasic/sarcomatoid) histology because of its similarly poor prognosis. We sought to investigate whether preoperative maximum standardized uptake value (SUVmax) on F-fluorodeoxyglucose (FDG) positron emission tomography (PET) correlates with histologic subtype in MPM.

METHODS

Clinical data were collected for 78 patients with MPM who underwent preoperative FDG-PET. We retrospectively classified the epithelioid tumors into five subtypes: trabecular, tubulopapillary, micropapillary, solid, and pleomorphic. Tumors were categorized by SUVmax into two groups: low (<10.0) and high (≥10.0).

RESULTS

The median overall survival of epithelioid tumors with high SUVmax (n = 12) was significantly shorter (7.1 months) than that of epithelioid tumors with low SUVmax (n = 54, 18.9 months, p < 0.001) and comparable to nonepithelioid tumors (n = 12, 7.2 months). Epithelioid tumors with pleomorphic subtype (n = 9) had marginally higher SUVmax (mean ± SD: 10.6 ± 5.9) than epithelioid nonpleomorphic subtype (n = 57, 6.5 ± 3.2, p = 0.050), and were comparable to that of nonepithelioid tumors (n = 12, 9.1 ± 4.8). Among the epithelioid tumors with high SUVmax (n = 12), 50% (n = 6) showed pleomorphic subtype. In contrast, among epithelioid tumors with low SUVmax (n = 54), 6% (n = 3) showed epithelioid pleomorphic subtypes (p = 0.001). A positive correlation between mitotic count and SUVmax was observed (r = 0.30, p = 0.010).

CONCLUSIONS

Pleomorphic subtype of epithelioid MPM showed higher SUVmax than the epithelioid nonpleomorphic subtype and was similar to nonepithelioid histology. Preoperative SUVmax on FDG-PET in epithelioid MPM can indicate patients with pleomorphic subtype with poor prognosis, supporting their reclassification as nonepithelioid.

FDG-PET SUVmax combined with IASLC/ATS/ERS histologic classification improves the prognostic stratification of patients with stage I lung adenocarcinoma

BACKGROUND

We investigated the association between the newly proposed International Association for the Study of Lung Cancer (IASLC)/American Thoracic Society (ATS)/European Respiratory Society (ERS) classification and (18)F-fluorodeoxyglucose (FDG) uptake on positron emission tomography (PET), and whether the combination of these radiologic and pathologic factors can further prognostically stratify patients with stage I lung adenocarcinoma.

METHODS

We retrospectively evaluated 222 patients with pathologic stage I lung adenocarcinoma who underwent FDG-PET scanning before undergoing surgical resection between 1999 and 2005. Patients were classified by histologic grade according to the IASLC/ATS/ERS classification (low, intermediate, or high grade) and by maximum standard uptake value (SUVmax) (low <3.0, high ≥3.0). The cumulative incidence of recurrence (CIR) was used to estimate recurrence probabilities.

RESULTS

Patients with high-grade histology had higher risk of recurrence (5-year CIR, 29% [n = 25]) than those with intermediate-grade (13% [n = 181]) or low-grade (11% [n = 16]) histology (p = 0.046). High SUVmax was associated with high-grade histology (p < 0.001) and with increased risk of recurrence compared to low SUVmax (5-year CIR, 21% [n = 113] vs. 8% [n = 109]; p = 0.013). Among patients with intermediate-grade histology, those with high SUVmax had higher risk of recurrence than those with low SUVmax (5-year CIR, 19% [n = 87] vs. 7% [n = 94]; p = 0.033). SUVmax was associated with recurrence even after adjusting for pathologic stage (p = 0.037).

CONCLUSIONS

SUVmax on FDG-PET correlates with the IASLC/ATS/ERS classification and can be used to stratify patients with intermediate-grade histology, the predominant histologic subtype, into two prognostic subsets.

Ratio of positron emission tomography uptake to tumor size in surgically resected non-small cell lung cancer

BACKGROUND

In patients with non-small cell lung cancer (NSCLC), previous studies have shown a prognostic benefit of maximum standardized uptake (SUV(max)) values on positron emission tomography (PET). Because tumor size is also prognostic and is associated with SUV(max), we sought to better characterize their relationship. We hypothesize that the ratio of SUV(max) to tumor size is a clinically useful measurement.

METHODS

A retrospective review was performed for patients (tumors ≥ 1 cm) undergoing resection of NSCLC. Patients were placed into quartiles (SUV(max) and SUV(max) to tumor size ratio) and compared for clinical and pathologic factors. Predictors of SUV(max) and SUV(max) to tumor size ratio on survival were evaluated.

RESULTS

Among 530 patients, increasing tumor size (odds ratio [OR], 2.04; confidence interval [CI], 1.68-2.47; p < 0.001) was an independent predictor of higher SUV(max). Patients in quartiles by the ratio of SUV(max) to tumor size demonstrated no significant difference in median tumor size. Those patients with the highest ratios (QR4, 3.21-27.5) more frequently had poorly differentiated tumors (51%; p < 0.001), were likely to have lymph node metastases (30%; p < 0.001), and had poor 3-year disease-free survival (DFS) (58%; p = 0.013). On multivariate analysis, as a continuous variable SUV(max) to tumor size ratio was a stronger independent predictor of survival than SUV(max) alone (hazard ratio [HR], 1.06; CI, 1.00-1.13 versus HR, 1.02; CI, 0.99-1.06). Using cutpoint analysis, a high SUV(max) to tumor size ratio was also a stronger predictor of survival than was high SUV(max) alone, particularly for tumors 1-3 cm (HR, 1.53; CI, 0.93-2.53 versus HR, 1.15; CI, 0.69-1.93).

CONCLUSIONS

The ratio of SUV(max) to tumor size may be a more important indicator of prognosis than SUV(max) alone in patients with NSCLC. In particular, the use of the ratio may be appropriate for identifying patients with small tumors who are at high risk for lymph node metastases and poor survival.

Clinical outcome and predictors of survival and pneumonitis after stereotactic ablative radiotherapy for stage I non-small cell lung cancer

Background

Stereotactic ablative radiotherapy (SABR) can achieve excellent local control rates in early-stage non-small cell lung cancer (NSCLC) and has emerged as a standard treatment option for patients who cannot undergo surgery or those with isolated recurrences. However, factors that may predict toxicity or survival are largely unknown. We sought here to identify predictors of survival and pneumonitis after SABR for NSCLC in a relatively large single-institution series.

Methods

Subjects were 130 patients with stage I NSCLC treated with four-dimensional computed tomography (4D CT) –planned, on-board volumetric image–guided SABR to 50 Gy in 4 fractions. Disease was staged by positron emission tomography/computed tomography (PET/CT) and scans were obtained again at the second follow-up after SABR.

Results

At a median follow-up time of 26 months, the 2-year local control rate was 98.5%. The median overall survival (OS) time was 60 months, and OS rates were 93.0% at 1 year, 78.2% at 2 years, and 65.3% at 3 years. No patient experienced grade 4–5 toxicity; 15 had radiation pneumonitis (12 [9.3%] grade 2 and 3 [2.3%] grade 3). Performance status, standardized uptake value (SUV)_max on staging PET/CT, tumor histology, and disease operability were associated with OS on univariate analysis, but only staging SUV_max was independently predictive on multivariate analysis (P = 0.034). Dosimetric factors were associated with radiation pneumonitis on univariate analysis, but only mean ipsilateral lung dose ≥9.14 Gy was significant on multivariate analysis (P = 0.005).

Conclusions

OS and radiation pneumonitis after SABR for stage I NSCLC can be predicted by staging PET SUV_max and ipsilateral mean lung dose, respectively.

Stereotactic body radiotherapy (SBRT) for non-small cell lung cancer (NSCLC): is FDG-PET a predictor of outcome?

BACKGROUND AND PURPOSE

Distant metastases are the dominant mode of failure after stereotactic body radiotherapy (SBRT) for early-stage non-small cell lung cancer (NSCLC). The primary study objective was to evaluate if the maximum standardized uptake value (SUV(max)) on pre-treatment FDG-PET/CT predicted clinical outcomes. Secondary objectives were to correlate 3-month post-SBRT SUV(max) and change in SUV(max) with outcomes.

MATERIALS AND METHODS

Consecutive patients with medically inoperable early-stage NSCLC and an FDG-PET/CT scan before (n=82) and 3 months after (n=62) SBRT.

RESULTS

Median follow up was 2 years. On univariate analysis baseline SUV(max) predicted for distant failure (p=0.0096), relapse free survival (RFS) (p=0.037) and local failure (p=0.044). On multivariate analysis baseline SUV(max) predicted for RFS (p=0.037). Baseline SUV(max) of above 5 was the most statistically significant cut off point for predicting distant failure (p=0.0002). Baseline SUV(max) ≥4.75 (median) was correlated with a higher risk of distant failure (p=0.012) and poorer RFS (p=0.04). Patients with a post-SBRT SUV(max) ≥2 and a reduction of <2.55 had a significantly higher rate of distant failure.

CONCLUSIONS

Pre-SBRT SUV(max) on FDG-PET/CT correlated most strongly with distant failure. A cut off of ≥5 was the most significant. Post-SBRT SUV(max) ≥2 and a reduction of <2.55 were associated with a higher risk of distant failure.

Baseline SUVmax at PET-CT in stage IIIA non-small-cell lung cancer patients undergoing surgery after neoadjuvant therapy: prognostic implication focused on histopathologic subtypes

RATIONALE AND OBJECTIVES

To evaluate the prognostic significance of maximum standardized uptake value (SUVmax) at (18)F-fluorodeoxyglucose (FDG) positron emission tomography-computed tomography in patients with stage IIIA non-small-cell lung cancer (NSCLC) who underwent surgical resection after neoadjuvant chemoradiotherapy, focused on the relationship between SUVmax values and tumor histology.

MATERIALS AND METHODS

We retrospectively evaluated the initial SUVmax of 205 patients (112 adenocarcinomas, 82 squamous cell carcinomas [SCCs], and 11 of other histology) with a stage IIIA NSCLC who underwent surgical resection after neoadjuvant chemoradiotherapy, and who were followed for up to 6 years. Clinical data, including histologic type, pathologic response, and treatment, were reviewed, and the relationship between the SUVmax and patient overall survival was examined.

RESULTS

Overall, the 2-year survival rate was 68%. Between the two histologic subtypes of adenocarcinoma and SCC, we noted significant differences in all variables of gender (male predominance in SCC), initial SUVmax (greater in SCC), pathologic response (more complete remission in SCC), and overall survival (better in SCC) (all P values, < .05). SUVmax remained as a sole independent factor for survival in multivariate analysis in whole series (SUVmax cutoff, 13; median survival, 3.0 years vs. 4.0 years; P = .016) and in adenocarcinomas (SUVmax cutoff, 11.5; median survival, 2.6 years vs. 3.6 years; P = .045), but not in SCCs.

CONCLUSION

The initial SUVmax is a sole significant prognostic factor in patients with a surgically resected NSCLC after neoadjuvant chemoradiotherapy, particularly in patients with an adenocarcinoma.

Standard uptake value of positron emission tomography in clinical stage I lung cancer: clinical application and pathological correlation

OBJECTIVES

The aim of this study was to assess the standard uptake value in clinical stage I non-small cell lung cancer (NSCLC) and its correlation with pathological status and prognosis.

METHODS

We retrospectively reviewed 674 patients diagnosed with NSCLC between January 2002 and June 2005. Patients with clinical stage I diseases undergone a preoperative positron emission tomography-computed tomography scan followed by anatomic resection. We reviewed the clinical features of 152 patients with an average follow-up of 87 months.

RESULTS

We analysed the clinical features of 108 patients with stage I NSCLC and 44 patients with non-stage I NSCLC. There were no statistical differences in age, histological type, location or tumour differentiation between the two groups. In the Stage I group, the patients had lower maximum standard uptake value (SUVmax; 3.80 ± 3.17 vs 5.73 ± 3.65, P = 0.001), lower carcinoembryonic antigen (CEA) levels (2.86 ± 4.80 vs 9.11 ± 17.21 ng/ml, P = 0.027) and smaller tumour size (2.39 ± 0.98 vs 3.73 ± 2.04 cm, P < 0.001). The patients with higher SUVmax had a more advanced pathological stage, poorer tumour differentiation and larger tumour size. A higher SUVmax was an independent factor predicting an advanced pathological stage (SUVmax ≥ 3.3, odds ratio 3.246). The median survival of patients with SUVmax ≥ 3.3 and SUVmax <3.3 were 64.32 and 53.08 months, respectively (P = 0.654).

CONCLUSIONS

Higher preoperative 18-fluorodeoxyglucose uptake by a tumour was significantly associated with an advanced pathological stage but not correlated with a poorer prognosis. An aggressive preoperative work-up for occult N2 disease should be emphasized, avoiding inappropriate thoracotomy.

Functional imaging in predicting response to antineoplastic agents and molecular targeted therapies in lung cancer: a review of existing evidence

The increasing use of FDG-PET ((18)F-2-fluoro-2-deoxy-d-glucose positron emission tomography) imaging in the staging of non-small-cell lung cancer (NSCLC) may result in a significant shift in stage distribution, with an increased percentage of patients staged as having metastatic disease and consequently a higher percentage of patients treated with systemic therapy. The amount of FDG-PET uptake in primary lung lesions has been shown to be correlated with tumour growth rate. Data suggest that tumours with increased glucose uptake are presumably more metabolically active and more biologically aggressive, and standardized uptake value (SUV) at PET may be regarded as a prognostic factor. Growing evidence suggests that PET may be used as a predictive marker to assess the activity of antineoplastic agents, allowing close monitoring of the efficacy of the treatment in order to be able to switch earlier to alternative therapies according to the individual chemosensitivity of the tumour. Currently the value of FDG-PET for monitoring response is complicated by the heterogeneity of the published data on the methods used for FDG quantification and the selection of the primary targets and clinical endpoints. As a result, objective validation of proposed thresholds of responsiveness is lacking. This article discusses the assessment of treatment response in NSCLC patients using functional imaging, and emphasizes advantages and limitations in clinical management.