Relationship between Non-Small Cell Lung Cancer Fluorodeoxyglucose Uptake at Positron Emission Tomography and Surgical Stage with Relevance to Patient Prognosis

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.

Predictive value of interim 18F-FDG-PET in patients with non-small cell lung cancer treated with definitive radiation therapy

PURPOSE

We evaluated that early metabolic response determined by 18F-fluorodeoxyglucose positron emission tomography/computed tomography (FDG-PET/CT) during radiotherapy (RT), predicts outcomes in non-small cell lung cancer.

MATERIAL AND METHODS

Twenty-eight patients evaluated using pretreatment 18F-FDG-PET/CT (PETpre) and interim 18F-FDG-PET/CT (PETinterim) after 11 fractions of RT were retrospectively reviewed. Maximum standardized uptake value (SUVmax) was calculated for primary lesion. Predictive value of gross tumor volume (ΔGTV) and SUVmax (ΔSUVmax) changes was evaluated for locoregional control (LRC), distant failure (DF), and overall survival (OS). Metabolic responders were patients with ΔSUVmax >40%.

RESULTS

Metabolic responders showed better trends in 1-year LRC (90.9%) than non-responders (47.1%) (p = 0.086). Patients with large GTVpre (≥120 cc) demonstrated poor LRC (hazard ratio 4.14, p = 0.022), while metabolic non-responders with small GTVpre (<120 cc) and metabolic responders with large GTVpre both had 1-year LRC rates of 75.0%. Reduction of 25% in GTV was not associated with LRC; however, metabolic responders without a GTV response showed better 1-year LRC (83.3%) than metabolic non-responders with a reduction in GTV (42.9%). Metabolic responders showed lower 1-year DF (16.7%) than non-responders (50.0%) (p = 0.025). An ΔSUVmax threshold of 40% yielded accuracy of 64% for predicting LRC, 75% for DF, and 54% for OS. However, ΔGTV > 25% demonstrated inferior diagnostic values than metabolic response.

CONCLUSIONS

Changes in tumor metabolism diagnosed using PETinterim during RT better predicted treatment responses, recurrences, and prognosis than other factors historically used.

Prognostic value of dual-point fluorine-18 fluorodeoxyglucose PET imaging, partial volume correction and glucose transporter-1 expression in resected nonsmall cell lung cancer patients

OBJECTIVE

To investigate the relationship between the prognosis and glucose transporter-1 (Glut-1) expression or fluorine-18 fluorodeoxyglucose uptake using partial volume correction and dual-point imaging in surgically resected nonsmall cell lung cancer (NSCLC) patients.

METHODS

Our patient population consisted of 108 NSCLC cases. The early maximum standardized uptake value (ESUVmax), delayed SUVmax (DSUVmax), partial volume correction SUVmax (cSUVmax) and retention index of primary lesions were calculated. Cox proportional hazard model was applied to evaluate the effects of PET parameters and Glut-1 expression. Overall survival (OS) and disease-free survival (DFS) were evaluated by Kaplan-Meier methods, and the difference in survival between subgroups was analyzed by log-rank test.

RESULTS

On the Cox regression analysis, ESUVmax, DSUVmax, cSUVmax and Glut-1 were significantly related to DFS [ESUVmax, hazard ratio = 2.301, 95% confidential interval (CI) = 1.146-4.618, P = 0.019; DSUVmax, hazard ratio = 2.483, 95% CI = 1.257-4.905, P = 0.009; cSUVmax, hazard ratio = 2.205, 95% CI = 1.038-4.686, P = 0.04; Glut-1, hazard ratio = 2.095, 95% CI = 1.086-4.041, P = 0.001] and OS (ESUVmax, hazard ratio = 3.197, 95% CI = 1.339-7.633, P = 0.009; DSUVmax, hazard ratio = 3.599, 95% CI = 1.521-8.516, P = 0.004; cSUVmax, hazard ratio = 8.655, 95% CI = 2.048-36.658, P = 0.003; Glut-1, hazard ratio = 2.427, 95% CI = 5.140, P = 0.021). Retention index had no significant association with DFS or OS. On the Kaplan-Meier survival curves, the patients with high ESUVmax, DSUVmax, cSUVmax and Glut-1 showed significantly worse prognosis than those with low values (ESUVmax: DFS, P = 0.001, OS, P = 0.003; DSUVmax: DFS, P = 0.002, OS, P = 0.004; cSUVmax: DFS, P < 0.001, OS, P = 0.013; Glut-1: DFS, P = 0.012, OS, P = 0.002).

CONCLUSIONS

cSUVmax, ESUVmax, DSUVmax and Glut-1 may be more useful biomarkers than retention index for predicting outcomes in NSCLC patients.

Volumetric parameters on 18F-FDG PET/CT predict the survival of patients with gastric cancer associated with their expression status of c-MET

Background

This study aimed to investigate the prognostic value of volumetric parameters on ¹⁸F- fluoro-2-deoxy-D-glucose (¹⁸F-FDG) positron emission tomography/computed tomography (PET/CT) in gastric-cancer patients, according to the expression status of c-MET (MET proto-oncogene, receptor tyrosine kinase), which was previously unclear.

Methods

The study included 61 patients with advanced gastric cancer. Data on the baseline ¹⁸F-FDG PET/CT, clinical-pathological information, progression-free survival (PFS), and overall survival (OS) were collected. The maximum standardized uptake value (SUV_max), peak SUV (SUV_peak), metabolic tumor volume (MTV), and total lesion glycolysis (TLG) of gastric tumors in situ were measured on PET/CT. The expression status of c-MET was recorded based on immunohistochemical staining. Associations between the parameters on PET/CT and patients’ survival outcomes were analyzed in relation to expression status of c-MET.

Results

Patients with positive c-MET expression had significantly shorter PFS (11.5 vs. 17.6 months, P = 0.039) and OS (17.0 vs. 24.3 months, P = 0.043), and had gastric tumors with a larger MTV (70.8 ± 53.11 vs. 41.1 ± 52.32, P = 0.034) and TLG (428.39 ± 442.95 vs. 205.7 ± 354.40, P = 0.039), compared with those with negative c-MET expression. However, SUV_max (9.6 ± 7.40 vs. 8.0 ± 4.91, P = 0.335) and SUV_peak (7.7 ± 5.99 vs. 6.62 ± 4.08, P = 0.438) were similar between these two patient groups. In patients with c-MET-positive tumors, MTV and TLG were independent factors in predicting patient OS after correction by distant metastasis (hazards ratio = 1.014 and 1.002, respectively; P = 0.024 and 0.027, respectively), while these associations were not significant in patients with c-MET-negative tumors.

Conclusions

Patients with c-MET-positive gastric cancer had higher MTV and TLG values compared to those with c-MET-negative gastric cancer. In patients with c-MET-positive gastric cancer, volumetric parameters on ¹⁸F-FDG PET/CT have prognostic value for patient overall survival.

Quantitative FDG PET/CT may help risk-stratify early-stage non-small cell lung cancer patients at risk for recurrence following anatomic resection

BACKGROUND

Preoperative identification of non-small cell lung cancer (NSCLC) patients at risk for disease recurrence has proven unreliable. The extraction of quantitative metrics from imaging based on tumor intensity and texture may enhanced disease characterization. This study evaluated tumor-specific 18F-fluorodeoxyglucose (18F-FDG) positron emission tomography/computerized tomography (PET/CT) uptake patterns and their association with disease recurrence in early-stage NSCLC.

METHODS

Sixty-four stage I/II NSCLC patients who underwent anatomic resection between 2001 and 2014 were examined. Pathologically or radiographic confirmed disease recurrence within 5 years of resection comprised the study group. Quantitative imaging metrics were extracted within the primary tumor volume. Squamous cell carcinoma (SCC) (N=27) and adenocarcinoma (AC) (N=41) patients were compared using a Wilcoxon signed-rank test. Associations between imaging and clinical variables with 5-year disease-free survival (DFS) and overall survival (OS) were evaluated by Cox proportional-hazards regression.

RESULTS

Clinical and pathologic characteristics were similar between recurrence (N=34) and patients achieving 5-year DFS (N=30). Standardized uptake value (SUV)max and SUVmean varied significantly by histology, with SCC demonstrating higher uptake intensity and heterogeneity patterns. Entropy-grey-level co-occurrence matrix (GLCM) was a significant univariate predictor of DFS (HR =0.72, P=0.04) and OS (HR =0.65, P=0.007) independent of histology. Texture features showed higher predictive ability for DFS in SCC than AC. Pathologic node status and staging classification were the strongest clinical predictors of DFS, independent of histology.

CONCLUSIONS

Several imaging metrics correlate with increased risk for disease recurrence in early-stage NSCLC. The predictive ability of imaging was strongest when patients are stratified by histology. The incorporation of 18F-FDG PET/CT texture features with preoperative risk factors and tumor characteristics may improve identification of high-risk patients.

The prognostic value of volume-based parameters using 18F-FDG PET/CT in gastric cancer according to HER2 status

BACKGROUND

We aimed to find the clinical value of metastatic tumor burden evaluated with F18-FDG PET/CT in gastric cancer patients, considering the human epidermal growth factor receptor 2 (HER2) status.

METHODS

We retrospectively reviewed 124 patients with locally advanced or metastatic gastric cancer at Yonsei Cancer Center between January 2006 and December 2014 who had undergone baseline FDG PET/CT before first-line chemotherapy. We measured the maximum standardized uptake value from the primary tumor (SUV_max) and whole-body (WB) PET/CT parameters, including WB SUV_max, WB SUV_mean, WB metabolic tumor volume (WB MTV), and WB total lesion glycolysis (WB TLG), in all metabolically active metastatic lesions (SUV threshold ≥2.5 or 40% isocontour for ≤2.5), and we determined their association with patient survival outcomes.

RESULTS

SUV_max was higher in HER2-positive gastric cancers (median 12.1, range 3.4-34.6) compared to HER-2 negative (7.4, 1.6-39.1, P < 0.001). Among all patients, WB TLG > 600, which is indicative of a high metastatic tumor burden, showed worse progression-free survival (PFS) [hazard ratio (HR), 2.003; 95% CI, 1.300-3.086; P = 0.002] and overall survival (OS) (HR, 3.001; 95% CI, 1.950-4.618; P < 0.001) than did WB TLG ≤ 600. Among HER2-positive gastric cancer patients treated with trastuzumab, higher metabolic tumor burden predicted worse OS, but not PFS.

CONCLUSIONS

HER2-positive gastric cancers had higher SUV_max compared to HER2-negative gastric cancers. In both HER2-negative patients and -positive patients receiving trastuzumab, FDG PET/CT volume-based parameters may have a role in further stratifying the prognosis of stage IV gastric cancer.

Impact of partial-volume correction in oncological PET studies: a systematic review and meta-analysis

Purpose

Positron-emission tomography can be useful in oncology for diagnosis, (re)staging, determining prognosis, and response assessment. However, partial-volume effects hamper accurate quantification of lesions <2–3× the PET system’s spatial resolution, and the clinical impact of this is not evident. This systematic review provides an up-to-date overview of studies investigating the impact of partial-volume correction (PVC) in oncological PET studies.

Methods

We searched in PubMed and Embase databases according to the PRISMA statement, including studies from inception till May 9, 2016. Two reviewers independently screened all abstracts and eligible full-text articles and performed quality assessment according to QUADAS-2 and QUIPS criteria. For a set of similar diagnostic studies, we statistically pooled the results using bivariate meta-regression.

Results

Thirty-one studies were eligible for inclusion. Overall, study quality was good. For diagnosis and nodal staging, PVC yielded a strong trend of increased sensitivity at expense of specificity. Meta-analysis of six studies investigating diagnosis of pulmonary nodules (679 lesions) showed no significant change in diagnostic accuracy after PVC (p = 0.222). Prognostication was not improved for non-small cell lung cancer and esophageal cancer, whereas it did improve for head and neck cancer. Response assessment was not improved by PVC for (locally advanced) breast cancer or rectal cancer, and it worsened in metastatic colorectal cancer.

Conclusions

The accumulated evidence to date does not support routine application of PVC in standard clinical PET practice. Consensus on the preferred PVC methodology in oncological PET should be reached. Partial-volume-corrected data should be used as adjuncts to, but not yet replacement for, uncorrected data.

Electronic supplementary material

The online version of this article (doi:10.1007/s00259-017-3775-4) contains supplementary material, which is available to authorized users.

Ratio of Lymph Node to Primary Tumor SUV on PET/CT Accurately Predicts Nodal Malignancy in Non-Small-Cell Lung Cancer

Thoracic lymph nodes with marginally elevated maximum standardized uptake value (SUVmax) on PET/CT a diagnostic challenge in staging non-small-cell lung cancer. We evaluated the ratio of lymph node to primary tumor SUVmax (SUVN/T) in predicting nodal malignancy among 132 sampled nodes from 85 patients both a primary tumor SUVmax > 2.5 and LN SUVmax 2.0 to 6.0. SUVN/T was more accurate than SUVmax for this subset of patients.

INTRODUCTION/BACKGROUND

Among non-small-cell lung cancers with appreciable functional activity, positron emission tomography/computed tomography (PET/CT) is the most accurate imaging modality for clinical staging. However, lymph nodes (LN) with marginally elevated standardized uptake value (SUV) present a diagnostic challenge. In this retrospective study, we hypothesized that normalizing the LN SUV by using the ratio of the LN to primary tumor SUVmax (SUVN/T) may be a better predictor of nodal malignancy than using SUVmax alone for nodes with low to intermediate SUV.

PATIENTS AND METHODS

We identified 172 patients with newly diagnosed non-small-cell lung cancer who underwent pathologic LN staging and PET/CT within 31 days before biopsy. Receiver operating characteristic curves with area under the curve (AUC) calculations were used to evaluate SUVmax and SUVN/T for their ability to predict nodal malignancy for both the entire cohort of 504 LNs and a subset of 132 LNs from 85 patients who had both primary tumor SUVmax > 2.5 and LN SUVmax 2.0 to 6.0.

RESULTS

In patients with primary tumor SUVmax > 2.5 and LN SUVmax 2.0 to 6.0, SUVN/T was significantly more accurate in predicting nodal malignancy (AUC, 0.846; 95% confidence interval, 0.775-0.917) than SUVmax (AUC, 0.653; 95% confidence interval, 0.548-0.759). The optimal cutoff value of SUVN/T to predict nodal malignancy was 0.28 (90% sensitivity, 68% specificity). Sensitivity was > 95% for SUVN/T < 0.21, whereas specificity was > 95% for SUVN/T > 0.50.

CONCLUSION

The ratio of LN SUV to primary tumor SUV on PET/CT is more accurate than SUVmax when assessing nodes of low to intermediate SUV.

FDG-PET Response Prediction in Pediatric Hodgkin's Lymphoma: Impact of Metabolically Defined Tumor Volumes and Individualized SUV Measurements on the Positive Predictive Value

Background: In pediatric Hodgkin’s lymphoma (pHL) early response-to-therapy prediction is metabolically assessed by (18)F-FDG PET carrying an excellent negative predictive value (NPV) but an impaired positive predictive value (PPV). Aim of this study was to improve the PPV while keeping the optimal NPV. A comparison of different PET data analyses was performed applying individualized standardized uptake values (SUV), PET-derived metabolic tumor volume (MTV) and the product of both parameters, termed total lesion glycolysis (TLG); Methods: One-hundred-eight PET datasets (PET1, n = 54; PET2, n = 54) of 54 children were analysed by visual and semi-quantitative means. SUVmax, SUVmean, MTV and TLG were obtained the results of both PETs and the relative change from PET1 to PET2 (Δ in %) were compared for their capability of identifying responders and non-responders using receiver operating characteristics (ROC)-curves. In consideration of individual variations in noise and contrasts levels all parameters were additionally obtained after threshold correction to lean body mass and background; Results: All semi-quantitative SUV estimates obtained at PET2 were significantly superior to the visual PET2 analysis. However, ΔSUVmax revealed the best results (area under the curve, 0.92; p < 0.001; sensitivity 100%; specificity 85.4%; PPV 46.2%; NPV 100%; accuracy, 87.0%) but was not significantly superior to SUVmax-estimation at PET2 and ΔTLGmax. Likewise, the lean body mass and background individualization of the datasets did not impove the results of the ROC analyses; Conclusions: Sophisticated semi-quantitative PET measures in early response assessment of pHL patients do not perform significantly better than the previously proposed ΔSUVmax. All analytical strategies failed to improve the impaired PPV to a clinically acceptable level while preserving the excellent NPV.

Relationship between primary lesion metabolic parameters and clinical stage in lung cancer

OBJECTIVES

The relation of PET-derived parameters as maximum standardized uptake value (SUVmax), total lesion glycolysis (TLG), metabolic tumor volume (MTV) with clinical stage in lung cancer and correlation of SUVmax of primary tumor and that of metastatic lesion was studied in lung cancer patients.

MATERIALS AND METHODS

Patients with lung cancer who were referred for FDG PET/CT were included in the study.

RESULTS

PET/CT scans and pathology reports of 168 patients were assessed. A total of 146 (86.9%) of these patients had a diagnosis of non-small cell lung cancer (NSCLC) and 22 (13.1%) had small cell lung cancer (SCLC). Metabolic parameters such as SUVmax, TLG and MTV showed significant differences in all the stages in NSCLC patients (p<0.001). However, after tumors sizes <25 mm were excluded, no significant differences in SUVmax between stages were observed. No significant differences were found between these metabolic parameters and limited or extended disease SCLC. Tumor diameter correlated with primary tumor SUVmax and significant correlations between primary lesion SUVmax and metastatic lesion SUVmax were found.

CONCLUSIONS

Although differences were found regarding indices between stages of NSCLC cases, SUVmax differences between stages seem to be caused by underestimation of SUVmax in small lesions. Other glucose metabolism indexes such as MTV and TLG show promising results in terms of prognostic stratification. Future studies are needed for better understanding of their contribution to clinical cases.

Predictive value of 18F-fluorodeoxyglucose uptake by positron emission tomography for non-small cell lung cancer patients treated with radical radiotherapy

The purpose of this study is to assess predictive value of the positron emission tomography (PET) with 18F-fluoro-deoxyglucose (FDG) for recurrence and survival after radiotherapy (RT) for non-small cell lung cancer (NSCLC). One hundred forty-nine patients underwent pretreatment PET (n = 67) or PET/computed tomography (CT) (n = 82) and definitive RT for NSCLC. We evaluated the relationship between the maximum-pixel standardized uptake value (SUV(max)) and clinical tumor features. Univariate Cox proportional hazard analysis (UVA) was used to quantify the risk for local-regional recurrence, distant metastases, and death. Multivariate Cox proportional hazard analysis (MVA) was used to assess the potential independent effect of SUV(max). In the PET group, T1 tumors showed significantly lower SUV(max) than T2, T3, and T4 tumors; in the PET/CT group, T1 tumors showed significantly lower SUV(max) than T3 and T4 tumors. A high SUV(max )was a negative factor for local-regional control (LRC) (p < 0.001), distant metastasis-free survival (DMFS) (p = 0.02), and overall survival (OS) (p = 0.001) on UVA in the PET group. However, the significance decreased to 0.05 for LRC, 0.04 for DMFS, and 0.04 for OS by MVA when tumor size was included in the analysis. A high SUV(max) was not a negative factor for LRC, DMFS, or OS on UVA and MVA in the PET/CT group. In conclusion, assessment of predictive value of SUV(max) for NSCLC requires consideration of primary tumor size, and the evidence is not sufficient to suggest that FDG uptake in a primary NSCLC provides prognostic information.

Prognostic value of 18F-FDG uptake on positron emission tomography in patients with pathologic stage I non-small cell lung cancer

INTRODUCTION

The intensity of 18F-fluorodeoxyglucose (18F-FDG) uptake in positron emission tomography could be of prognostic significance for patients with non-small cell lung cancer (NSCLC). The aim of this retrospective study was to evaluate the prognostic value of the FDG uptake in patients with resected pathologic stage I NSCLC according to histologic types of the tumors.

METHODS

For each patient, a maximum standardized uptake value (SUVmax) and a partial volume corrected (PVC) SUVmax were calculated for the primary lesion on positron emission tomography. To find optimal cutoff values for cancer recurrences, receiver operating characteristic curves were used.

RESULTS

Among 145 study patients, the mean values of SUVmax were 7.7 in those with adenocarcinoma (n = 70) and 16.0 in those with other histologies (n = 75; p < 0.001). Furthermore, the optimal cutoff values of SUVmax to predict cancer recurrences were identified as 5.2 in patients with adenocarcinoma and 13.8 in those with other histologies. In whole patients with pathologic stage I NSCLC, SUVmax (p = 0.025), PVC SUVmax (p = 0.014), tumor size (p = 0.048), and weight loss (p = 0.041) were significantly associated with disease-free survival (DFS). Moreover, PVC SUVmax (p = 0.034) and SUVmax (p = 0.012) were significantly associated with DFS in the multivariate analyses.

CONCLUSIONS

The intensity of FDG uptake for the primary tumor was an independent prognostic factor for DFS in whole patients with pathologic stage I NSCLC. However, caution is needed for the interpretation of optimal cutoff values of SUVmax according to tumor histologies.

DNA hypermethylation of tumors from non-small cell lung cancer (NSCLC) patients is associated with gender and histologic type

BACKGROUND

We previously identified a number of genes which were methylated significantly more frequently in the tumor compared to the non-cancerous lung tissues from non-small cell lung cancer (NSCLC) patients. Detection of methylation profiles of genes in NSCLC could provide insight into differential pathways to malignancy and lead to strategies for better treatment of individuals with NSCLC.

METHODS

We determined the DNA methylation status of 27 genes using quantitative MethyLight assays in lung tumor samples from 117 clinically well-characterized NSCLC patients.

RESULTS

Hypermethylation was detected in one of more of the genes in 106 (91%) of 117 cases and was detected at high levels (percentage methylation reference (PMR)> or =4%) in 79% of NSCLC cases. Methylation of APC, CCND2, KCNH5 and, RUNX was significantly more frequent in adenocarcinomas compared to squamous cell carcinomas (SCC), while methylation of CDKN2A was more common in SCC. Hypermethylation of KCNH5, KCNH8, and RARB was more frequent in females compared to males. Hypermethylation of APC and CCND2 was inversely associated with proliferation score assessed by Ki-67 level.

CONCLUSIONS

Our findings of differential gene hypermethylation frequencies in tumor tissues from patients with adenocarcinoma or squamous cell cancers and in females compared to males suggests that further investigation is warranted in order to more fully understand the potential disparate pathways and/or risk factors for NSCLC associated with histologic type and gender.

Revisiting the prognostic value of preoperative (18)F-fluoro-2-deoxyglucose ( (18)F-FDG) positron emission tomography (PET) in early-stage (I & II) non-small cell lung cancers (NSCLC)

PURPOSE

The aims were to determine if the maximum standardized uptake value (SUV(max)) of the primary tumor as determined by preoperative (18)F-fluoro-2-deoxyglucose ((18)F-FDG) positron emission tomography (PET) is an independent predictor of overall survival and to assess its prognostic value after stratification according to pathological staging.

METHODS

A retrospective clinicopathologic review of 363 patients who had a preoperative (18)F-FDG PET done before undergoing attempted curative resection for early-stage (I & II) non-small cell lung cancer (NSCLC) was performed. Patients who had received any adjuvant or neoadjuvant chemotherapy or radiation therapy were excluded. The primary outcome measure was duration of overall survival. Receiver-operating characteristic (ROC) curves were plotted to find out the optimal cutoff values of SUV(max) yielding the maximal sensitivity plus specificity for predicting the overall survival. Survival curves stratified by median SUV(max) and optimal cutoff SUV(max) were estimated by the Kaplan-Meier method and statistical differences were assessed using the log-rank test. Multivariate proportional hazards (Cox) regression analyses were applied to test the SUV(max)'s independency of other prognostic factors for the prediction of overall survival.

RESULTS

The median duration of follow-up was 981 days (2.7 years). The median SUV(max) was 5.9 for all subjects, 4.5 for stage IA, 8.4 for stage IB, and 10.9 for stage IIB. The optimal cutoff SUV(max) was 8.2 for all subjects. No optimal cutoff could be established for specific stages. In univariate analyses, each doubling of SUV(max) [i.e., each log (base 2) unit increase in SUV(max)] was associated with a 1.28-fold [95% confidence interval (CI): 1.03-1.59, p = 0.029] increase in hazard of death. Univariate analyses did not show any significant difference in survival by SUV(max) when data were stratified according to pathological stage (p = 0.119, p = 0.818, and p = 0.882 for stages IA, IB, and IIB, respectively). Multivariate analyses demonstrated that SUV(max) was not an independent predictor of overall survival (p > 0.05).

CONCLUSION

Each doubling of SUV(max) as determined by preoperative PET is associated with a 1.28-fold increase in hazard of death in early-stage (I & II) NSCLC. Preoperative SUV(max) is not an independent predictor of overall survival.

Thymidine kinase 1 and thymidine phosphorylase expression in non-small-cell lung carcinoma in relation to angiogenesis and proliferation

The thymidine salvage pathway enzymes thymidine kinase 1 (TK1) and thymidine phosphorylase (TP) compete for thymidine as a substrate and catalyze opposing synthetic and catabolic reactions that have been implicated in the control of proliferation and angiogenesis, respectively. We investigated the relationship between the expression of TK1 and TP as they relate to proliferation (Ki-67 labeling index) and angiogenesis (Chalkley count of CD31-stained blood vessels) in a series of 110 non-small-cell lung cancer (NSCLC) tumors from patients prospectively enrolled in an imaging trial. TK1 and TP exhibited similar patterns of immunohistochemical distribution, in that each was found in both the nucleus and the cytoplasm of tumor cells. Each enzyme exhibited a significant positive correlation between its levels of nuclear and cytoplasmic expression. A significant positive correlation between TK1 expression and the Ki-67 labeling index (r = 0.53, p<0.001) was observed. TP was significantly positively correlated with Chalkley scoring of CD31 staining in high vs low Chalkley scoring samples (mean TP staining of 115.8 vs 79.9 scoring units, p<0.001), respectively. We did not observe a substantial inverse correlation between the TP and TK1 expression levels in the nuclear compartment (r = -0.17, p=0.08). Tumor size was not found to be associated with TK1, TP, Ki-67, or Chalkley score. These findings provide additional evidence for the role of thymidine metabolism in the complex interaction of proliferation and angiogenesis in NSCLC.

FDG PET/CT and mediastinal nodal metastasis detection in stage T1 non-small cell lung cancer: prognostic implications

Objective

We aimed to compare the prognoses of patients with pathologically true negative (P-TN) N2 and PET/CT false negative (FN) results in stage T1 non-small cell lung cancer (NSCLC).

Materials and Methods

Our institutional review board approved this retrospective study with a waiver of informed consent. The study included 184 patients (124 men and 60 women; mean age, 59 years) with stage T1 NSCLC who underwent an integrated PET/CT and surgery. After estimating the efficacy of PET/CT for detecting N2 disease, we determined and compared disease-free survival (DFS) rates in three groups (P-TN [n = 161], PET/CT FN [n = 12], and PET/CT true positive [TP, n = 11]) using the Kaplan-Meier analysis and log-rank test.

Results

Pathologic N2 disease was observed in 23 (12%) patients. PET/CT had an N2 disease detection sensitivity of 48% (11 of 23 patients), a specificity of 95% (153 of 161), and an accuracy of 89% (164 of 184). The 3-year DFS rate in the PET/CT FN group (31%, 95% confidence interval [CI]; 13.6-48.0%) was similar to that of the TP group (16%, 95% CI; 1.7-29.5%) (p = 0.649), but both groups had significantly shorter DFS rates than the P-TN group (77%, 95% CI; 72.0-81.2%) (p < 0.001).

Conclusion

The PET/CT shows a high specificity, but low sensitivity for detecting N2 disease in stage T1 NSCLC. Patients with PET/CT FN N2 disease have survival rates similar to PET/CT TP N2 disease patients, which are both substantially shorter than the survival rate of P-TN patients.

18F-fluoro-2-deoxy-D-glucose standardized uptake value in cavitating non-small-cell lung carcinoma

PURPOSE

Cavitation in lung tumours has been considered as a specific clinical subentity related to worse prognosis and reduced survival. This study was performed to assess glycolysis as maximum standardized uptake value (SUVmax) on F-fluoro-2-deoxy-D-glucose PET imaging, a known prognostic factor in lung cancer and an index of tumour aggression in cavitated tumours.

MATERIALS AND METHODS

Thirty-one patients with biopsy-proved, cavitated, non-small cell lung cancer (NSCLC) underwent PET/computed tomography staging scans. SUVmax readings were compared with those of 37 patients with solid NSCLC tumours but with similar staging. Maximum tumour diameters were recorded together with survival at 2 years.

RESULTS

Mean SUVmax, corrected for body weight, of the cavitated tumours was 14+/-6.8, compared with 13.5+/-10.8 for the solid tumours. No significant difference on paired t-tests was seen (P=0.83). The maximum diameter of the tumour was significantly greater (P<0.05) for the cavitated tumours (5.8+/-2.4 cm) than for solid tumours (4.4+/-2.4 cm). Six patients with cavitated tumours died at 2 years compared with 11 with solid tumours; no significant difference in survival (two-sided P value=0.48, Fisher's exact test) was observed between patients with cavitated tumours and those with solid tumours.

CONCLUSION

These findings do not support cavitation as a separate prognostic feature in NSCLC. Only tumour diameter was increased overall in the cavitated group. No increased glycolysis on PET/computed tomography imaging, relative to solid tumours, was seen and overall survival at 2 years seemed similar between the two groups.

DNA methylation in tumor and matched normal tissues from non-small cell lung cancer patients

We used MethyLight assays to analyze DNA methylation status of 27 genes on 49 paired cancerous and noncancerous tissue samples from non-small cell lung cancer (NSCLC) patients who underwent surgical resection. Seven genes (RARB, BVES, CDKN2A, KCNH5, RASSF1, CDH13, and RUNX) were found to be methylated significantly more frequently in tumor tissues than in noncancerous tissues. Only methylation of CCND2 and APC was frequently detected in both cancerous and noncancerous tissues, supporting the hypothesis that the methylation of these two genes is a preneoplastic change and may be associated with tobacco smoking exposure. Methylation of any one of eight genes (RASSF1, DAPK1, BVES, CDH13, MGMT, KCNH5, RARB, or CDH1) was present in 80% of NSCLC tissues but only in 14% of noncancerous tissues. Detection of methylation of these genes in blood might have utility in monitoring and detecting tumor recurrence in early-stage NSCLC after curative surgical resection.

Predictive and prognostic value of FDG-PET

The predictive and prognostic value of fluorodeoxyglucose (FDG)-positron emission tomography (PET) in non-small-cell lung carcinoma, colorectal carcinoma and lymphoma is discussed. The degree of FDG uptake is of prognostic value at initial presentation, after induction treatment prior to resection and in the case of relapse of non-small cell lung cancer (NSCLC). In locally advanced and advanced stages of NSCLC, FDG-PET has been shown to be predictive for clinical outcome at an early stage of treatment. In colorectal carcinoma, limited studies are available on the prognostic value of FDG-PET, however, the technique appears to have great potential in monitoring the success of local ablative therapies soon after intervention and in the prediction and evaluation of response to radiotherapy, systemic therapy, and combinations thereof. The prognostic value of end-of treatment FDG-PET for FDG-avid lymphomas has been established, and the next step is to define how to use this information to optimize patient outcome. In Hodgkin's lymphoma, FDG-PET has a high negative predictive value, however, histological confirmation of positive findings should be sought where possible. For non-Hodgkin's lymphoma, the opposite applies. The newly published standardized guidelines for interpretation formulates specific criteria for visual interpretation and for defining PET positivity in the liver, spleen, lung, bone marrow and small residual lesions. The introduction of these guidelines should reduce variability among studies. Interim PET offers a reliable method for early prediction of long-term remission, however it should only be performed in prospective randomized controlled trials. Many of the diagnostic and management questions considered in this review are relevant to other tumour types. Further research in this field is of great importance, since it may lead to a change in the therapeutic concept of cancer. The preliminary findings call for systematic inclusion of FDG-PET in therapeutic trials to adequately position FDG-PET in treatment time lines.

Predictive and prognostic value of FDG-PET in nonsmall-cell lung cancer: a systematic review

For several years, molecular imaging with (18)F-fluorodeoxyglucose positron emission tomography (FDG-PET) has become part of the standard of care in presurgical staging of patients with nonsmall-cell lung cancer (NSCLC), focusing on the detection of malignant lesions at early stages, early detection of recurrence, and metastatic spread. Currently, there is an increasing interest in the role of FDG-PET beyond staging, such as the evaluation of biological characteristics of the tumor and prediction of prognosis in the context of treatment stratification and the early assessment of tumor response to therapy. In this systematic review, the literature on the value of the evolving applications of FDG-PET as a marker for prediction (ie, therapy response monitoring) and prognosis in NSCLC is addressed, divided in sections on the predictive value of FDG-PET in locally advanced and advanced disease, the prognostic value of FDG-PET at diagnosis, after induction treatment, and in recurrent disease. Furthermore, the background and recommendations for the application of FDG-PET for these indications will be discussed.

Fluorodeoxyglucose uptake of primary non-small cell lung cancer at positron emission tomography: new contrary data on prognostic role

PURPOSE

This prospective study evaluated the prognostic significance of (18)F-fluorodeoxyglucose ((18)F-FDG) uptake in primary non-small cell lung cancer (NSCLC) at positron emission tomography, in a carefully staged population, while correcting for partial volume effects.

EXPERIMENTAL DESIGN

Two hundred eight potentially resectable NSCLC patients were referred for FDG positron emission tomography staging after thoracic computed tomography. Each tumor stage was confirmed surgically, or for some stage IV tumors by additional imaging. The tumor maximum pixel-standardized uptake value (maxSUV) and the maxSUV partial volume corrected for lesion size (PVCmaxSUV) were compared with overall survival and disease-free survival using Cox proportional hazards regression.

RESULTS

Stage distribution: stage I, 36%; stage II, 15%; stage III, 30%; stage IV, 19%. Patients were followed for a median of 33.6 months, with 90 deaths from NSCLC (median survival for all stages, 43.3 months). With respect to overall survival, the most significant cutoff value for both maxSUV and PVCmaxSUV was 7. MaxSUV > or =7 was significantly associated with an increased risk of death from NSCLC in univariable analysis, whereas PVCmaxSUV > or =7 was only marginally associated. However, in multivariable analyses, neither maxSUV > or =7 nor PVCmaxSUV > or =7 provided significant additional prognostic information over stage, tumor size, and age. In the 103 patients who underwent surgical resection only, surgical stage, but not maxSUV or PVCmaxSUV, was univariably associated with survival or recurrence. SUV definitions based on lean body mass, body surface area, and plasma glucose correction yielded identical results.

CONCLUSIONS

As expected, tumor stage is prognostic in NSCLC. However, tumor FDG uptake does not provide additional prognostic information. This prospective study contradicts prior reports.

Modeling a Better Way: Navigating the Healthcare System for Patients With Lung Cancer

The coordination of services for patients with suspected or newly diagnosed lung cancer produces improved patient outcomes, particularly in their quality of life. Evidence-based practice demonstrates improved outcomes from the multimodality therapies offered today, especially for patients with lung cancer; however, navigating through the healthcare system is especially challenging for patients. In developing the Multidisciplinary Lung Cancer Clinic at Frederick Memorial Hospital, navigation challenges in the healthcare system have been addressed. Patients are receptive and pleased with the approach, in which a nurse practitioner coordinates services and provides guidance and support for patients. The program offers benefits to patients with lung cancer in the community hospital setting. A similar program can be implemented in community cancer centers for patients with other diagnoses to improve outcomes and satisfaction with the healthcare system.

Fluorine-18 fluorodeoxyglucose positron emission tomographic maximal standardized uptake value predicts survival independent of clinical but not pathologic TNM staging of resected non-small cell lung cancer

OBJECTIVES

Positron emission tomographic maximal standardized uptake value has been shown to predict survival after resection of non-small cell lung cancer. The relative prognostic benefit of maximal standardized uptake value with respect to other clinical/pathologic variables has not been defined.

METHODS

We reviewed patients who had positron emission tomographic imaging and an R0 resection for non-small cell lung cancer between January 1, 2000, and December 31, 2004, without induction or adjuvant therapy. The associations between overall survival, histology, pathologic TNM stage, pathologic tumor diameter, and standardized uptake value were tested.

RESULTS

Four hundred eighty-seven patients met the study criteria. Median follow-up was 25.8 months. By using the median values for tumor size (2.5 cm) and standardized uptake value (5.3), standardized uptake value was an independent predictor of survival (P = .03), adjusting for tumor size (P = .02) and histology (P < .01). The optimal standardized uptake value for stratification was identified as 4.4, and this value was identified as an independent predictor of survival (P = .03) after adjusting for clinical TNM stage. Standardized uptake value was not an independent predictor of survival (P = .09), adjusting for pathologic TNM stage (stage IA vs IB vs stage II-IV, P < .01).

CONCLUSIONS

Standardized uptake value does not add to the prognostic significance of pathologic TNM stage. Standardized uptake value was an independent prognostic factor from clinical TNM stage.

Biological correlates of FDG uptake in non-small cell lung cancer

PURPOSE

Each pathological stage of non-small cell lung cancer (NSCLC) consists of a heterogeneous population containing patients at much higher risk than others. Noninvasive functional imaging modalities, such as 18F-fluorodeoxyglucose positron emission tomography (FDG-PET), could play a role in further characterization of NSCLCs. As many factors can influence the extent of FDG uptake, the underlying mechanisms for FDG accumulation in tumors, are still a matter of debate. The aim of the present study was to investigate these possible mechanisms in the primary site of early stage preoperatively untreated NSCLC.

METHODS

19 patients with early stage NSCLC, who had undergone both preoperative FDG-PET imaging and curative surgery, were enrolled in this study. Standardized uptake values (SUVs) were used for evaluation of primary tumor FDG uptake. Final diagnosis, tumor type, tumor cell differentiation and size of the primary tumors were confirmed histopathologically in resected specimens. Histologic sections were analyzed for amount of inflammation and necrosis. Expression of the glucose membrane transporters (GLUT-1 and GLUT-3); the isoforms of the glycolytic enzyme hexokinase (HK-I, HK-II and HK-III); and the cysteine protease caspase-3, was evaluated immunohistochemically.

RESULTS

FDG uptake was significantly higher in squamous cell carcinomas (mean SUV 13.4+/-4.9, n=8) compared to adenocarcinomas (7.1+/-3.3, n=8, p=0.007), or large cell carcinomas (5.9+/-1.9, n=3, p=0.02). The degree of FDG accumulation seemed to depend especially on GLUT-1, GLUT-3 and tumor cell differentiation. The summed standardized values of these three parameters correlated significantly with the SUV (r=0.47, p=0.05).

CONCLUSION

The present study supports the hypothesis that tumor cell differentiation in combination with overexpression of GLUT-1 and GLUT-3 determine the extent of FDG accumulation and that squamous cell carcinomas accumulate more FDG than adenocarcinomas or large cell carcinomas.

The prognostic value of positron emission tomography in non-small cell lung cancer: Analysis of 266 cases

Positron emission tomography (PET) is more accurate than computed tomography (CT) in the staging of non-small cell lung cancer (NSCLC). We analyzed the prognostic value of PET for survival in NSCLC patients.

METHODS

Consecutive patients with proven NSCLC with PET for staging were selected. Staging by laboratory tests, bronchoscopy, chest X-ray, and CT was performed in all patients, leading to a clinical stage (c-TNM) prior to PET. A separate classification (pet-TNM) was obtained from PET images by observers blinded to clinical data. We performed univariate survival analysis with ECOG performance score, sex, weight loss, comorbidity, histology, c-TNM, and pet-TNM as variables. Cox regression analysis was performed with significant variables from the univariate analyses.

RESULTS

Two hundred and sixty-six patients were included, 205 men and 61 women. c-TNM and pet-TNM were identical in 150 (56%) patients, 69 were upstaged, and 47 were downstaged by PET. At time of analysis, 198 (74%) patients had died. Univariate analysis showed significant survival differences for ECOG performance score (0 versus 1/2), weight loss (<10% versus >or=10%), pulmonary comorbidity, c-TNM, and pet-TNM (stage IA versus IB, IIA, IIB, IIIA, IIIB, IV). Cox regression analysis identified pet-TNM as the most significant (p < 0.001) prognostic factor, followed by ECOG performance score (p = 0.018).

CONCLUSION

Tumor stage as determined by PET is the most significant prognostic factor for survival in patients with NSCLC.

Progress and promise of FDG-PET imaging for cancer patient management and oncologic drug development

2-[(18)F]Fluoro-2-deoxyglucose positron emission tomography (FDG-PET) assesses a fundamental property of neoplasia, the Warburg effect. This molecular imaging technique offers a complementary approach to anatomic imaging that is more sensitive and specific in certain cancers. FDG-PET has been widely applied in oncology primarily as a staging and restaging tool that can guide patient care. However, because it accurately detects recurrent or residual disease, FDG-PET also has significant potential for assessing therapy response. In this regard, it can improve patient management by identifying responders early, before tumor size is reduced; nonresponders could discontinue futile therapy. Moreover, a reduction in the FDG-PET signal within days or weeks of initiating therapy (e.g., in lymphoma, non-small cell lung, and esophageal cancer) significantly correlates with prolonged survival and other clinical end points now used in drug approvals. These findings suggest that FDG-PET could facilitate drug development as an early surrogate of clinical benefit. This article reviews the scientific basis of FDG-PET and its development and application as a valuable oncology imaging tool. Its potential to facilitate drug development in seven oncologic settings (lung, lymphoma, breast, prostate, sarcoma, colorectal, and ovary) is addressed. Recommendations include initial validation against approved therapies, retrospective analyses to define the magnitude of change indicative of response, further prospective validation as a surrogate of clinical benefit, and application as a phase II/III trial end point to accelerate evaluation and approval of novel regimens and therapies.