Sex and SUVmax: sex-dependent prognostication in early non-small cell lung cancer

Four-dimensional quantitative analysis using FDG-PET in clinical oncology

Positron emission tomography (PET) with F-18 fluorodeoxyglucose (FDG) has been commonly used in many oncological areas. High-resolution PET permits a three-dimensional analysis of FDG distributions on various lesions in vivo, which can be applied for tissue characterization, risk analysis, and treatment monitoring after chemoradiotherapy and immunotherapy. Metabolic changes can be assessed using the tumor absolute FDG uptake as standardized uptake value (SUV) and metabolic tumor volume (MTV). In addition, tumor heterogeneity assessment can potentially estimate tumor aggressiveness and resistance to chemoradiotherapy. Attempts have been made to quantify intratumoral heterogeneity using radiomics. Recent reports have indicated the clinical feasibility of a dynamic FDG PET-computed tomography (CT) in pilot cohort studies of oncological cases. Dynamic imaging permits the assessment of temporal changes in FDG uptake after administration, which is particularly useful for differentiating pathological from physiological uptakes with high diagnostic accuracy. In addition, several new parameters have been introduced for the in vivo quantitative analysis of FDG metabolic processes. Thus, a four-dimensional FDG PET-CT is available for precise tissue characterization of various lesions. This review introduces various new techniques for the quantitative analysis of FDG distribution and glucose metabolism using a four-dimensional FDG analysis with PET-CT. This elegant study reveals the important role of tissue characterization and treatment strategies in oncology.

Preoperative PET-SUVmax and volume based PET parameters of the primary tumor fail to predict nodal upstaging in early-stage lung cancer

OBJECTIVES

Accurate nodal staging is of utmost importance in patients with lung cancer. FDG-PET/CT imaging is now part of the routine staging. Despite thorough preoperative staging nodal upstaging still occurs in early-stage lung cancer. However, the predictive value of preoperative PET metrics of the primary tumor on nodal upstaging remains to be unexplored. Our aim was to assess the association of these preoperative PET-parameters with nodal upstaging in histologically confirmed lung adenocarcinoma and squamous cell carcinoma.

METHODS

From January 2016 to November 2018, 500 patients with pT1-T2/cN0 lung cancer received an anatomical resection with curative intent. 171 patients with adenocarcinoma and squamous cell carcinoma and available PET-CTs were retrospectively included. We analyzed the the association of nodal upstaging with preoperative PET-SUVmax and metabolic PET metrics including total lesion glycolysis (TLG) and metabolic tumor volume (MTV) with different defined thresholds.

RESULTS

High values of preoperative PET-SUVmax of the primary tumor were associated with squamous cell carcinoma (p < 0.0001) and with larger tumors (p < 0.0001). Increased preoperative C-reactive protein levels (<1mg/dL) correlated significantly with high preoperative PET-SUVmax values (p < 0.0001). No significant relationship between PET-SUVmax and lactate dehydrogenase activity (p = 0.6818), white blood cell count (p = 0.7681), gender (p = 0.1115) or age (p = 0.9284) was observed. Nodal upstaging rate was 14.0 % with 8.8 % N1 and 5.3 % N2 upstaging. Tumor size (p = 0.0468) and number of removed lymph nodes (p = 0.0461) were significant predictors of nodal upstaging but no significant association was found with histology or PET parameters. Of note, increased MTV - regardless of the threshold - tended to associate with nodal upstaging.

CONCLUSION

Early-stage lung cancer patients with squamous histology and T2 tumors presented increased preoperative PET-SUVmax values. Nevertheless, beyond tumor size and number of removed lymph nodes neither SUVmax nor metabolic PET parameters MTV and TLG were significant predictors of nodal upstaging.

The value of the Standardized Uptake Value (SUV) and Metabolic Tumor Volume (MTV) in lung cancer

The diagnosis, staging and therapeutic monitoring of lung cancer were amongst the first applications for which the utility of FDG PET was documented and FDG PET/CT is now a routine diagnostic tool for clinical decision-making. As well as having high sensitivity for detection of disease sites, which provides critical information about stage, the intensity of uptake provides deeper biological characterization, while the burden of disease also has potential clinical significance. These disease characteristics can easily be quantified on delayed whole-body imaging as the maximum standardized uptake value (SUV_max) and metabolic tumor volume (MTV), respectively. There have been significant efforts to harmonize the measurement of these features, particularly within the context of clinical trials. Nevertheless, however calculated, in general, a high SUV_max and large MTV have been shown to have an adverse prognostic significance. Nevertheless, the use of these parameters in the interpretation and reporting of clinical scans remains inconsistent and somewhat controversial. This review details the current status of semi-quantitative FDG PET/CT in the evaluation of lung cancer.

Evaluation of fluorine-18-fluorodeoxyglucose PET/computed tomography and human epithelial growth factor receptor 2 expression in treatment-naive patients with lung adenocarcinoma

OBJECTIVE

Human epithelial growth factor receptor 2 (HER2) is overexpressed in several types of cancers. The correlation between tumor glucose activity and HER2 expression can vary. This study is a retrospective investigation of fluorine-18-fluorodeoxyglucose PET/computed tomography (18F-FDG PET/CT) and HER2 expression status in patients with lung adenocarcinoma.

METHODS

The maximum standard uptake value (SUVmax) of 18F-FDG PET/CT was compared with the HER2 expression status in pretreated patients with lung adenocarcinoma. Moreover, clinicopathological characteristics, including age, gender, smoking, serum tumor markers, tumor location, size, stage and genetic mutation, were also evaluated in groups with different HER2 expressions. Patients' progression-free survival (PFS) and overall survival (OS) were also analyzed.

RESULTS

Ninety-six patients with HER2 expression, including 54 patients with HER2 overexpression and 30 patients without HER2 expression were enrolled in this study. The primary pulmonary lesion was single in all patients, and all lesions were FDG-avid on PET/CT. SUVmax had no significant association with HER2 expression or overexpression in lung adenocarcinoma. Moreover, elevated serum CYFRA211 levels were obviously associated with HER2 expression but not associated with HER2 overexpression. There were no significant differences in other clinicopathological characteristics in groups with different HER2 expressions. Furthermore, multivariate Cox regression analysis revealed that SUVmax, HER2 expression and tumor node metastasis stage were independent predictors of PFS, and SUVmax, CYFRA211 and epidermal growth factor receptor mutation were independent predictors of OS.

CONCLUSION

SUVmax had no significant association with the HER2 expression status in lung adenocarcinoma. 18F-FDG PET/CT and HER2 expression could provide valuable prognostic information for treatment-naive patients with lung adenocarcinoma.

Integrated analysis of long non-coding RNAs and mRNA profiles reveals potential sex-dependent biomarkers of bevacizumab/erlotinib response in advanced lung cancer

Background

While lung cancer patient outcomes are well-recognized to vary as a function of patient sex, there has been insufficient research regarding the relationship between patient sex and EGFR(Epidermal growth factor receptor) response efficacy. The present study therefore sought to identify novel sex-related biomarkers of bevacizumab/erlotinib (BE) responses in non-small cell lung cancer (NSCLC) patients.

Methods

The exon array data in the Gene Expression Omnibus (GEO) dataset were analyzed in order to identify patterns of mRNA and lncRNA expression associated with BE resistance in NSCLC. These differentially expressed (DE) lncRNAs and mRNAs were identified via DE Analysis Filtering. These DE mRNAs were then assessed for their potential functional roles via pathway enrichment analyses, with overlapping functions possibly associated with the BE resistance. The mRNAs in these overlapping groups were then assessed for their correlations with patient survival, and lncRNA-mRNA co-expression networks were generated for each patient subset. A protein-protein interaction (PPI) network was also generated based upon these DE mRNAs.

Results

In females we identified 172 DE lncRNAs and 1766 DE mRNAs associated with BE responses, while in males we identified 78 DE lncRNAs and 485 DE mRNAs associated with such responses. Based on the overlap between these two datasets, we identified a total of 37 GO functions and 18 pathways associated with BE responses. Co-expression and PPI networks suggested that the key lncRNAs and mRNAs associated with these BE response mechanisms weredifferent in the male and female patients.

Conclusions

This work is the first to conduct a global profiling of the relationship between lncRNA and mRNA expression patterns, patient sex, and BE responses in individuals suffering from NSCLC. Together these results suggest that the integrative lncRNA-mRNA expression analyses may offer invaluable new therapeutic insights that can guide the tailored treatment of lung cancer in order to ensure optimal BE responses.

Oncologic Outcomes of Surgery Versus SBRT for Non-Small-Cell Lung Carcinoma: A Systematic Review and Meta-analysis

BACKGROUND

The optimal treatment of stage I non-small-cell lung carcinoma is subject to debate. The aim of this study was to compare overall survival and oncologic outcomes of lobar resection (LR), sublobar resection (SR), and stereotactic body radiotherapy (SBRT).

METHODS

A systematic review and meta-analysis of oncologic outcomes of propensity matched comparative and noncomparative cohort studies was performed. Outcomes of interest were overall survival and disease-free survival. The inverse variance method and the random-effects method for meta-analysis were utilized to assess the pooled estimates.

RESULTS

A total of 100 studies with patients treated for clinical stage I non-small-cell lung carcinoma were included. Long-term overall and disease-free survival after LR was superior over SBRT in all comparisons, and for most comparisons, SR was superior to SBRT. Noncomparative studies showed superior long-term overall and disease-free survival for both LR and SR over SBRT. Although the papers were heterogeneous and of low quality, results remained essentially the same throughout a large number of stratifications and sensitivity analyses.

CONCLUSION

Results of this systematic review and meta-analysis showed that LR has superior outcomes compared to SBRT for cI non-small-cell lung carcinoma. New trials are underway evaluating long-term results of SBRT in potentially operable patients.

Sex-Dependent Staging in Non-Small-Cell Lung Cancer; Analysis of the Effect of Sex Differences in the Eighth Edition of the Tumor, Node, Metastases Staging System

INTRODUCTION

Non-small-cell lung cancer (NSCLC) has disproportionately negative outcomes in men compared with women. The importance of the relationship between sex and tumor, node, metastases (TNM) staging system remains unknown. The objective of this study was to investigate the effect of sex on NSCLC survival for each stage in the eighth edition of the TNM staging system in NSCLC.

PATIENTS AND METHODS

Two cohorts treated surgically with curative intent between 2000 and 2010 were analyzed. The primary cohort was from Australia with a second population set from the Surveillance, Epidemiology, and End Results (SEER) database. Univariate and multivariate analyses of putative and validated prognostic factors were undertaken to investigate sex-dependent prognostication with detailed analyses of sex differences in each TNM stage. The primary outcome was disease-specific survival (DSS) at 5 years.

RESULTS

Inclusion criteria were met by 555 patients in the Australian cohort, 335 men (60.4%) and 220 (39.6%) women; and 47,706 patients from the SEER cohort, 24,671 men (51.7%) and 23,035 women (48.3%). Five-year DSS was significantly worse for men in multivariate analyses for the Australian (hazard ratio [HR], 1.44; 95% confidence interval [CI], 1.04-1.98; P = .026) and SEER (HR, 1.24; 95% CI, 1.20-1.28; P < .001) cohorts. Detailed analysis of TNM stage sex differences revealed a consistent pattern of men having worse survival than women across stages in both cohorts.

CONCLUSION

The poorer survival in men with NSCLC presents research and clinical communities with an important challenge. This study's findings suggest that for men and women diagnosed with NSCLC, and managed surgically, stage-specific outcomes should be quoted separately and consideration to a rapid prognostic score with sex combined with staging as a key element.

Role of [¹⁸F]FDG PET in prediction of KRAS and EGFR mutation status in patients with advanced non-small-cell lung cancer

PURPOSE

The tumour molecular profile predicts the activity of epidermal growth factor receptor (EGFR) inhibitors in non-small-cell lung cancer (NSCLC). However, tissue availability and tumour heterogeneity limit its assessment. We evaluated whether [(18)F]FDG PET might help predict KRAS and EFGR mutation status in NSCLC.

METHODS

Between January 2005 and October 2011, 340 NSCLC patients were tested for KRAS and EGFR mutation status. We identified patients with stage III and IV disease who had undergone [(18)F]FDG PET/CT scanning for initial staging. SUVpeak, SUVmax and SUVmean of the single hottest tumour lesions were calculated, and their association with KRAS and EGFR mutation status was assessed. A receiver operator characteristic (ROC) curve analysis and a multivariate analysis (including SUVmean, gender, age and AJCC stage) were performed to identify the potential value of [(18)F]FDG PET/CT for predicting KRAS mutation.

RESULTS

From 102 patients staged using [(18)F]FDG PET/CT, 28 (27%) had KRAS mutation (KRAS+), 22 (22%) had EGFR mutation (EGFR+) and 52 (51%) had wild-type KRAS and EGFR profiles (WT). KRAS+ patients showed significantly higher [(18)F]FDG uptake than EGFR+ and WT patients (SUVmean 9.5, 5.7 and 6.6, respectively; p < 0.001). No significant differences were observed in [(18)F]FDG uptake between EGFR+ patients and WT patients. ROC curve analysis for KRAS mutation status discrimination yielded an area under the curve of 0.740 for SUVmean (p < 0.001). The multivariate analysis showed a sensitivity and specificity of 78.6% and 62.2%, respectively, and the AUC was 0.773.

CONCLUSION

NSCLC patients with tumours harbouring KRAS mutations showed significantly higher [(18)F]FDG uptake than WT patients, as assessed in terms of SUVpeak, SUVmax and SUVmean. A multivariate model based on age, gender, AJCC stage and SUVmean might be used as a predictive marker of KRAS mutation status in patients with stage III or IV NSCLC.

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.

Prospective evaluation of the clinical utility of 18-fluorodeoxyglucose PET CT scanning in patients with von hippel-lindau-associated pancreatic lesions

BACKGROUND

The natural history of pancreatic neuroendocrine neoplasms (PNENs) in patients with Von Hippel-Lindau (VHL) disease is poorly defined. Management of patients with PNENs is challenging because there are no reliable preoperative criteria to detect malignant lesions, and the majority of resected tumors are found to be benign. The aim of this study was to determine whether 18-fluorodeoxyglucose-positron emission tomography ((18)FDG-PET) uptake predicts growth and detects malignant VHL-associated PNENs.

STUDY DESIGN

We performed a prospective study of 197 patients with VHL-associated pancreatic lesions. Clinical and imaging characteristics were analyzed to study the associations between FDG-PET uptake, tumor growth, and the development of metastatic disease.

RESULTS

One hundred nine of 197 patients had solid pancreatic lesions and underwent both CT and (18)FDG-PET scanning, which identified 165 and 144 lesions, respectively. Metastatic disease was detected by (18)FDG-PET in 3 patients in whom it was not detected by CT scan and suggested non-neoplastic disease in 3 patients. Maximum standardized uptake values (SUV) on (18)FDG-PET correlated with tumor size on CT (r = 0.47, p < 0.0001), and an increase in SUVmax was associated with tumor growth (r = 0.36, p = 0.0062). No association was seen between (18)FDG-PET uptake and age, VHL genotype, or serum chromogranin A levels.

CONCLUSIONS

Scanning with FDG-PET identifies metastatic disease not detected by CT scan and avoids resection of non-PNEN lesions that have no malignant potential in patients with VHL-associated PNENs. It should be considered as a valuable functional imaging modality in the clinical management of patients with VHL-associated PNENs.