Measurement of tumor volume by PET to evaluate prognosis in patients with head and neck cancer treated by chemo-radiation therapy

Usefulness of Combined Metabolic-Volumetric Indices of (18)F-FDG PET/CT for the Early Prediction of Neoadjuvant Chemotherapy Outcomes in Breast Cancer

PURPOSE

The purpose of this study was to investigate the usefulness of metabolic-volumetric indices of (18)F- fluorodeoxy-D-glucose ((18)F-FDG) positron emission tomography/computed tomography (PET/CT) for the evaluation of neoadjuvant chemotherapy outcomes in breast cancer.

METHODS

Twenty-four patients with locally advanced breast cancer were enrolled in the study. They underwent baseline (18)F-FDG PET/CT scan and received four or six cycles of neoadjuvant chemotherapy, interim (18)F-FDG PET/CT was done after second cycle of chemotherapy. Maximum standardized uptake value (SUVmax), metabolic tumor volume (MTV), and total lesion glycolysis (TLG) of the primary lesions were calculated. Reduction rates of these parameters were obtained between baseline and interim (18)F-FDG PET/CT. Chemotherapy outcomes were assessed using tumor size reduction rate and histological grading system (Miller and Payne system). Reduction rates of SUVmax, MTV, and TLG correlated with chemotherapy outcomes.

RESULTS

MTV and TLG reduction rates showed significant correlation with tumor size reduction rate (R = 0.68, P = 0.0004; R = 0.62, P = 0.002, respectively). However, SUVmax reduction rate showed no significant correlation. MTV and TLG reduction rates were significantly higher in responders than nonresponders, as determined by Miller and Payne system (P < 0.0007, P < 0.002). However, SUVmax reduction rate showed no significant difference. On ROC analysis, the area under the MTV and TLG curves was 0.886, and that of SUVmax was 0.743. Sensitivity, specificity, positive predictive value, and negative predictive value to predict histopathologic response were the same for MTV and TLG, and the values were 100 %, 85.7 %, 83.3 %, and 100 %, respectively (at the reduction rate of 93.2 % for MTV, and 95.8 % for TLG).

CONCLUSION

Changes of metabolic-volumetric indices successfully reflected the neoadjuvant chemotherapy outcomes. MTV and TLG could be robust indices in discriminating pathologic responder as SUVmax, after neoadjuvant chemotherapy.

Predictive and prognostic value of metabolic tumour volume and total lesion glycolysis in solid tumours

Data available in patients suffering from squamous cell carcinoma of the head and neck, lung carcinoma, oesophageal carcinoma and gynaecological malignancies suggest that metabolic tumour volume and to a lesser extent total lesion glycolysis have the potential to become valuable in the imaging of human solid tumours as prognostic biomarkers for short- to intermediate-term survival outcomes, adding value to clinical staging, for assessment of response to treatment with neoadjuvant and concurrent chemotherapy, and for treatment optimization; for example, based on early treatment response assessment using changes in metabolic tumour volume over time, it might be possible to select patients who require a more aggressive treatment to improve their outcome. Prospective studies enrolling consecutive patients, adopting standardized protocols for FDG PET acquisition and processing, adjusting for potential confounders in the analysis (tumour size and origin) and determining the optimal methodology for determination of these novel markers are mandatory.

Prognostic value of 18F-FDG PET metabolic parameters in oropharyngeal squamous cell carcinoma

OBJECTIVE

To evaluate whether pretreatment metabolic parameters obtained from positron emission tomography (PET) with [¹⁸F]fluorodeoxyglucose (FDG) can improve risk prediction for patients with oropharyngeal squamous cell carcinoma (OPSCC) treated with definitive intensity-modulated radiation therapy (IMRT).

METHODS

Between 2003 and 2009, 86 patients with OPSCC had FDG-PET/CT prior to treatment with definitive IMRT. Chemotherapy was administered to 90 % of the patients. Metabolic tumor volume (MTV), total lesion glycolysis (TLG), maximum standardized uptake value (SUV_max), mean SUV (SUV_mean), and inverse coefficient of variation (1/CoV) were analyzed for the primary tumor alone and the total of the primary tumor and involved lymph nodes.

RESULTS

Median follow-up time for surviving patients was 41 months. On univariate analysis, total MTV and total TLG were significant predictors of disease-free survival (DFS) and overall survival (OS). SUV_max, SUV_mean, and 1/CoV failed to predict DFS or OS. On multivariate analysis controlling for T- and N-classification, total MTV remained a significant predictor of DFS and OS. The optimal cutpoint for total MTV was 20.5 ml. A total MTV >20.5 ml was associated with a 4.13-fold increased risk of death (95 % confidence interval [CI], 2.12-8.05; p < 0.0001). Total MTV remained a significant predictor of DFS and OS for the subgroups with p16-positive (n = 25) and p16-negative (n = 18) cancer.

CONCLUSION

Total MTV is an independent predictor of DFS and OS for patients with OPSCC treated with definitive radiotherapy. Total MTV remained predictive of DFS and OS for both p16-positive and p16-negative cancer.

The role of 18F-FDG PET/CT metabolic tumour volume in predicting survival in patients with metastatic nasopharyngeal carcinoma

OBJECTIVES

To investigate the role of PET-derived imaging markers in predicting metastatic nasopharyngeal carcinoma (NPC) outcomes.

MATERIALS AND METHODS

A total of 56 patients with metastatic NPC were enrolled. Before treatment, all of the participants underwent (18)F-FDG PET/CT. The following (18)F-FDG PET parameters were assessed: standardised uptake value, metabolic tumour volume (MTV), and total lesion glycolysis. Multivariate Cox proportional hazards models were used to identify the independent predictors of survival.

RESULTS

The multivariate analysis showed that performance status>1 (P=0.007), Epstein-Barr virus (EBV) DNA titre>5000 copies/mL (P=0.001), and MTV>110 mL (P=0.013) were independent risk factors for progression-free survival (PFS). Male sex (P=0.004), performance status>1 (P<0.0001), EBV DNA level>5000 copies/mL (P<0.0001), and MTV>110 mL (P=0.003) independently predicted overall survival (OS). The 2-year PFS and OS rates of the patients with MTV≤110 mL were 23.2% and 43%, respectively, compared with 0% and 9.1%, respectively, for those with MTV>110 mL. Combining the MTV with the EBV DNA titre allowed further survival stratification by dividing the patients into three groups with distinct PFS (2-year rates=30.8%, 7.1%, and 0%, P<0.0001) and OS (2-year rates=68.4%, 40%, and 0%, P<0.0001) rates.

CONCLUSION

The MTV appears to be an independent risk factor in metastatic NPC patients. This factor is complementary to the EBV DNA titre for predicting survival in metastatic NPC.

Metabolic Tumor Volume Measured by F-18 FDG PET/CT can Further Stratify the Prognosis of Patients with Stage IV Non-Small Cell Lung Cancer

PURPOSE

This study aimed to further stratify prognostic factors in patients with stage IV non-small cell lung cancer (NSCLC) by measuring their metabolic tumor volume (MTV) using F-18 fluorodeoxyglucose (FDG) positron emission tomography/computed tomography (PET/CT).

MATERIALS AND METHODS

The subjects of this retrospective study were 57 patients with stage IV NSCLC. MTV, total lesion glycolysis (TLG), and maximum standardized uptake value (SUVmax) were measured on F-18 FDG PET/CT in both the primary lung lesion as well as metastatic lesions in torso. Optimal cutoff values of PET parameters were measured by receiver operating characteristic (ROC) curve analysis. Kaplan-Meier survival curves were used for evaluation of progression-free survival (PFS). The univariate and multivariate Cox proportional hazards models were used to select the significant prognostic factors.

RESULTS

Univariate analysis showed that both MTV and TLG of primary lung lesion (MTV-lung and TLG-lung) were significant factors for prediction of PFS (P < 0.001, P = 0.038, respectively). Patients showing lower values of MTV-lung and TLG-lung than the cutoff values had significantly longer mean PFS than those with higher values. Hazard ratios (95 % confidence interval) of MTV-lung and TLG-lung measured by univariate analysis were 6.4 (2.5-16.3) and 2.4 (1.0-5.5), respectively. Multivariate analysis revealed that MTV-lung was the only significant factor for prediction of prognosis. Hazard ratio was 13.5 (1.6-111.1, P = 0.016).

CONCLUSION

Patients with stage IV NSCLC could be further stratified into subgroups of significantly better and worse prognosis by MTV of primary lung lesion.

The Application of FDG-PET as Prognostic Indicators in Head and Neck Squamous Cell Carcinoma

This article discusses the role of FDG-PETederived parameters as prognostic indicators in patients with squamous cell carcinoma of the head and neck. The basic underlying biology of FDG-PET scans and the quantitative information that can be derived are discussed. A review of the literature is performed. Potential applications in the management of head and neck cancer and future directions in clinical trials are discussed.

18F-FDG PET/CT metabolic tumor volume and total lesion glycolysis predict outcome in oropharyngeal squamous cell carcinoma

Treatment of oropharyngeal squamous cell carcinoma with chemoradiotherapy can now accomplish excellent locoregional disease control, but patient overall survival (OS) remains limited by development of distant metastases (DM). We investigated the prognostic value of staging (18)F-FDG PET/CT, beyond clinical risk factors, for predicting DM and OS in 176 patients after definitive chemoradiotherapy.

METHODS

The PET parameters maximum standardized uptake value (SUVmax), metabolic tumor volume (MTV), and total lesion glycolysis (TLG) were recorded. Univariate Cox regression was used to examine the prognostic value of these variables and clinical prognosticators for local treatment failure (LTF), OS, and DM. Multivariate analysis examined the effect of SUVmax, TLG, and MTV in the presence of other covariates. Kaplan-Meier curves were used to evaluate prognostic values of PET/CT parameters.

RESULTS

Primary tumors were distributed across all stages. Most patients underwent chemoradiotherapy only, and 11 also underwent tonsillectomy. On univariate analysis, primary tumor MTV was predictive of LTF (P = 0.005, hazard ratio [HR] = 2.4 for a doubling of MTV), DM and OS (P < 0.001 for both, HR = 1.9 and 1.8, respectively). The primary tumor TLG was associated with DM and OS (P < 0.001, HR = 1.6 and 1.7, respectively, for a doubling of TLG). The primary tumor SUVmax was associated with death (P = 0.029, HR = 1.1 for a 1-unit increase in standardized uptake value) but had no relationship with LTF or DM. In multivariate analysis, TLG and MTV remained associated with death after correcting for T stage (P = 0.0125 and 0.0324, respectively) whereas no relationship was seen between standardized uptake value and death after adjusting for T stage (P = 0.158).

CONCLUSION

Parameters capturing the volume of (18)F-FDG-positive disease (MTV or TLG) provide important prognostic information in oropharyngeal squamous cell carcinoma treated with chemoradiotherapy and should be considered for risk stratification in this disease.

Intra-reader reliability of FDG PET volumetric tumor parameters: effects of primary tumor size and segmentation methods

OBJECTIVE

To establish the effects of size and segmentation methods on intra-reader reliability of primary tumor metabolic tumor volume (MTV) and total glycolytic activity (TGA) in human solid tumors.

METHODS

This is a retrospective study of 121 patients who had a baseline FDG PET/CT scan for oncologic staging. Volumetric parameter readings were performed in random order on two separate occasions, 12 weeks apart, by the same reader. The MTV and TGA were segmented using gradient and fixed maximum standardized uptake value (SUVmax) threshold methods. Intra-reader reliability was established by the intraclass correlation coefficient (ICC) and Bland-Altman analysis.

RESULTS

The biases for MTV were 2.95, 14.76 and 11.13% for gradient segmentation, 38 and 50% SUVmax fixed threshold segmentations, respectively (p < 0.0001). For TGA, the corresponding biases were 0.76, 10.36 and 7.46% (p < 0.0001). There were no statistically significant differences in the biases between the first and second reads for MTV segmented for small and large volume tumors by the gradient method (p < 0.34) or 50% SUVmax threshold segmentation (p < 0.08). However, there were statistically significant differences in the corresponding biases for the 38% SUVmax threshold segmentation (p < 0.04). There were no statistically significant differences in the biases between the first and second reads for TGA segmented for small and large volume tumors (p < 0.98).

CONCLUSION

Intra-reader reliability for primary tumor FDG MTV and TGA is affected by the tumor size and segmentation methods. The segmentation bias was smaller for gradient method than percentage fixed threshold method for MTV. The segmentation biases were smaller for TGA than MTV.

FDG-PET-based prognostic nomograms for locally advanced cervical cancer

PURPOSE

We previously found several individual FDG/PET-based prognostic factors for cervical cancer, specifically cervical tumor SUVmax, tumor volume, and highest level of lymph node (LN) involvement. For this study, we evaluate the combined use of these three prognostic factors assessed on pretreatment FDG-PET for predicting recurrence-free survival (RFS), disease-specific survival (DSS), and overall survival (OS).

PATIENTS AND METHODS

The study included 234 cervical cancer patients, FIGO stage Ib1-IVa, treated with definitive radiation or chemoradiation therapy. All patients underwent FDG-PET or FDG-PET/CT at diagnosis, from which cervical tumor volume, SUVmax, and LN status were recorded. Using these PET-based factors, prognostic nomograms were created for RFS, DSS, and OS, and their prediction accuracies were measured using the concordance index (c-statistic).

RESULTS

Fifty-three percent of patients had FDG-avid LN on PET; the highest level of nodal involvement was pelvic in 84, para-aortic in 41, and supraclavicular in 10. The average cervix tumor SUVmax was 12.4 (range, 2.1-50.4) and PET tumor volume average was 66.4 cm3 (range, 3.0-535.7 cm3). The median follow-up was 40.7 months for patients alive at last follow-up. PET LN status had the greatest influence on outcome. The c-statistics for the 3 nomograms were 0.741 for RFS, 0.739 for DSS, and 0.658 for OS. The PET-based nomograms performed better than FIGO stage with c-statistics of 0.605, 0.600 and 0.559 for RFS, DSS and OS, respectively.

CONCLUSIONS

Pretreatment FDG-PET LN status, cervical tumor SUVmax, and tumor volume combined in a nomogram create good models for predicting cervical cancer RFS, DSS, and OS.

Prognostic value of tumor burden measurement using the number of tumors in non-surgical patients with non-small cell lung cancer

BACKGROUND

No study to test the feasibility and prognostic value of the number of primary tumors, the number of positive lymph nodes, and the total number of tumors in the whole body as tumor burden measurements on FDG PET/CT imaging has been reported.

PURPOSE

To determine whether the number of tumors seen in 18F-FDG PET scans can be a prognostic factor in non-surgical patients with non-small cell lung cancer (NSCLC).

MATERIAL AND METHODS

One hundred and forty patients with histologically proven NSCLC and baseline 18F-FDG PET scan before therapy were identified in this retrospective analysis. The total number of tumors (TTn) in the whole body, the number of primary tumors (Tn), positive lymph nodes (Nn), and distant metastases (Mn), along with the maximum standardized uptake values (SUV(max)) of the tumors were measured. Inter-observer variability of the total number of tumors, counted by two radiologists, was assessed. Survival analyses were performed to determine the prognostic value of the number of tumors.

RESULTS

Concordance correlation coefficients for the TTn, Tn, Nn, and Mn were all greater than 0.85. TTn and Nn were strong prognostic factors of NSCLC patients' overall survival (OS). In univariate Cox regression models, gender, stage, TTn, Nn, and Mn were statistically significant factors (P = 0.016, 0.032, <0.001, <0.001, and 0.006, respectively). In multivariate Cox regression models, TTn and Nn remained as statistically significant predictors for survival with hazard ratios (HR) of 1.06 (P = 0.001) and 1.11 (P = 0.002), respectively, after adjusting for clinical stage based 7th edition of TNM staging system, age, gender, and SUV(max). Patients with a TTn ≤4 (cutpoint based on median value) had a median OS of 15.2 months compared with 9.0 months for those with TTn >4.

CONCLUSION

Measuring the number of tumors on FDG PET imaging is easy to perform with minimal inter-observer variability. The total number of tumors and number of nodal metastases, as metabolic tumor burden measurements in 18F-FDG PET/CT, are prognostic markers independent of clinical stage, age, gender, and SUV measurement in non-surgical patients with NSCLC.

18F-FDG metabolic tumor volume and total glycolytic activity of oral cavity and oropharyngeal squamous cell cancer: adding value to clinical staging

(18)F-FDG metabolic tumor volume (MTV) and total glycolytic activity (TGA) have been proposed as potential prognostic imaging markers for patient outcome in human solid tumors. The purpose of this study was to establish whether MTV and TGA add prognostic information to clinical staging in patients with oral and oropharyngeal squamous cell carcinomas (SCCs).

METHODS

The Institutional Review Board approved this Health Insurance Portability and Accountability Act-compliant single-institution retrospective study. Forty-five patients with histologically proven oral or oropharyngeal SCC underwent PET/CT for initial cancer staging and were included in the study. MTV was measured using a gradient-based method (PET Edge) and fixed-threshold methods at 38%, 50%, and 60% of maximum standardized uptake value (SUV). The TGA is defined as MTV × mean SUV. Bland-Altman analysis was used to establish the reliability of the methods of segmentation. Outcome endpoints were overall survival (OS) and progression-free survival. Cox proportional hazards univariate and multivariate regression analyses were performed.

RESULTS

In Cox regression models, MTV and TGA were the only factors significantly associated with survival outcome after adjusting for all other covariates including American Joint Committee on Cancer (AJCC) stage, with hazards ratio of 1.06 (95% confidence interval, 1.01-1.10; P = 0.006) and 1.00 (95% confidence interval, 1.00-1.01; P = 0.02). The model fit was significantly better when MTV was added to AJCC stage in model I (χ(2) value change, 1.16-6.71; P = 0.01) and when TGA was added to AJCC stage in model II (χ(2) value change, 1.16-4.37; P = 0.04). The median cutoff point of 7.7 mL for primary tumor MTV was predictive of time to OS (log rank P = 0.04). The median cutoff point of 55 g for PET Edge primary tumor TGA was predictive of time to OS (log rank P = 0.08), though the result was not statistically significant.

CONCLUSION

Gradient-based segmentations of primary tumor MTV and TGA are potential (18)F-FDG markers for time to survival in patients with oral and oropharyngeal SCC and may provide prognostic information in addition to AJCC stage. These exploratory imaging markers need validation in larger cohort studies.

Prognostic value of gross tumor volume delineated by FDG-PET-CT based radiotherapy treatment planning in patients with locally advanced pancreatic cancer treated with chemoradiotherapy

Background

We aimed to assess whether gross tumor volume (GTV) determined by fusion of contrast-enhanced computerized tomography (CT) and 18F-fluoro-deoxy-D-glucose positron emission tomography-CT (FDG-PET-CT) based radiotherapy planning could predict outcomes, namely overall survival (OS), local-regional progression-free survival (LRPFS), and progression-free survival (PFS) in cases with locally advanced pancreas cancer (LAPC) treated with definitive concurrent chemoradiotherapy.

Methods

A total of 30 patients with histological proof of LAPC underwent 50.4 Gy (1.8 Gy/28 fractions) of radiotherapy concurrent with continuously infused 5-FU followed by 4 to 6 courses of maintenance gemcitabine. Target volume delineations were performed on FDG-PET-CT-based RTP. Patients were stratified into 2 groups: GTV lesser (GTV_L) versus greater (GTV_G) than cut off value determined by receiver operating characteristic (ROC) analysis, and compared in terms of OS, LRPFS and PFS.

Results

Median GTV delineated according to the FDG-PET-CT data was 100.0 cm³. Cut off GTV value determined from ROC curves was 91.1 cm³. At a median follow up of 11.2 months, median OS, LRPFS and PFS for the entire population were 10.3, 7.8 and 5.7 months, respectively. Median OS, LRPFS and PFS for GTV_L and GTV_G cohorts were 16.3 vs. 9.5 (p = 0.005), 11.0 vs. 6.0 (p = 0.013), and 9.0 vs. 4.8 months (p = 0.008), respectively.

Conclusions

The superior OS, LRPFS and PFS observed in GTV_L patients over GTV_G ones suggests a potential for FDG-PET-CT-defined GTV size in predicting outcomes of LAPC patients treated with definitive C-CRT, which needs to be validated by further studies with larger cohorts.

Prognostic value of metabolic tumor volume and velocity in predicting head-and-neck cancer outcomes

PURPOSE

We previously showed that metabolic tumor volume (MTV) on positron emission tomography-computed tomography (PET-CT) predicts for disease recurrence and death in head-and-neck cancer (HNC). We hypothesized that increases in MTV over time would correlate with tumor growth and biology, and would predict outcome. We sought to examine tumor growth over time in serial pretreatment PET-CT scans.

METHODS AND MATERIALS

From 2006 to 2009, 51 patients had two PET-CT scans before receiving HNC treatment. MTV was defined as the tumor volume ≥ 50% of maximum SUV (SUV(max)). MTV was calculated for the primary tumor, nodal disease, and composite (primary tumor + nodes). MTV and SUV velocity were defined as the change in MTV or SUV(max) over time, respectively. Cox regression analyses were used to examine correlations between SUV, MTV velocity, and outcome (disease progression and overall survival).

RESULTS

The median follow-up time was 17.5 months. The median time between PET-CT scans was 3 weeks. Unexpectedly, 51% of cases demonstrated a decrease in SUV(max) (average, -0.1 cc/week) and MTV (average, -0.3 cc/week) over time. Despite the variability in MTV, primary tumor MTV velocity predicted disease progression (hazard ratio 2.94; p = 0.01) and overall survival (hazard ratio 1.85; p = 0.03).

CONCLUSIONS

Primary tumor MTV velocity appears to be a better prognostic indicator of disease progression and survival in comparison to nodal MTV velocity. However, substantial variability was found in PET-CT biomarkers between serial scans. Caution should be used when PET-CT biomarkers are integrated into clinical protocols for HNC.

Prognostic value of the quantitative metabolic volumetric measurement on 18F-FDG PET/CT in Stage IV nonsurgical small-cell lung cancer

RATIONALE AND OBJECTIVES

Stage IV non-small-cell lung cancer (NSCLC) consists of a heterogeneous group of patients with different prognoses. We assessed the prognostic value of baseline whole body tumor burden as measured by metabolic tumor volume (MTV), total lesion glycolysis (TLG), and standardized uptake values (SUV(max) and SUV(mean)) of all tumors in nonsurgical patients with Stage IV NSCLC.

MATERIALS AND METHODS

Ninety-two consecutive patients with newly diagnosed Stage IV NSCLC who had a pretreatment F-18 fludeoxyglucose positron emission tomography/computed tomography scan were retrospectively reviewed. The MTV, TLG, SUV(mean), and SUV(max) of whole-body (WB) tumors were measured with the MIMvista workstation with manual adjustment.

RESULTS

There was a statistically significant association between overall survival (OS) and ln(MTV)/ln(TLG) at the level of WB tumor burden (MTV(WB)) and of primary tumor (MTV(T)). The hazard ratio (HR) for a 1-unit increase of ln(MTV(WB)) and ln(MTV(T)) before and after adjusting for age and gender was 1.48/1.48 (both P < .001) and 1.25/1.25 (P = .006, .007), respectively. The HR for a 1-unit increase of ln(TLG(WB)) and ln(TLG(T)) before and after adjusting for age and gender was 1.37/1.37 (both P = .001) and 1.19/1.19 (P = .001, .017), respectively. There was no statistically significant association between OS and ln(SUV(max)) and ln(SUV(mean)) at WB tumor burden, primary tumor, nodal metastasis, or distant metastasis (P > .05). There was low interobserver variability between two radiologists with concordance correlation coefficients of 0.90 for ln(MTV(WB)) and greater than 0.90 for SUV(maxWB), SUV(meanWB), and ln(TLG(WB)).

CONCLUSION

Baseline WB metabolic tumor burden, as measured with MTV and TLG, is a prognostic measurement in patients within Stage IV NSCLC with low interobserver variability. This study also suggests pretreatment MTV and TLG measurements may be used to further stratify patients with Stage IV NSCLC and are better prognostic measures than SUV(max) and SUV(mean) measurements.

Metabolic tumor volume is an independent prognostic factor in patients treated definitively for non-small-cell lung cancer

PURPOSE

Fluorine-18 flurodeoxyglucose positron emission tomography (FDG-PET) imaging has rapidly become the standard of care for staging patients with lung cancer. We evaluated the prognostic value of metabolic tumor volume (MTV), a measure of tumor burden on FDG-PET imaging, in patients with non-small-cell lung cancer (NSCLC) treated definitively.

METHODS AND MATERIALS

A retrospective review identified 61 patients with NSCLC who underwent FDG-PET imaging for pretreatment staging. Metabolically active tumor regions were segmented on the PET scans semiautomatically to calculate the total body MTV. We determined the relationship of overall survival (OS) and progression-free survival (PFS) with MTV in the entire cohort, and in the subgroup treated definitively.

RESULTS

The estimated median PFS and OS for the entire cohort were 11.1 months and 18.9 months. Higher MTV was significantly associated with worse OS (P = 0.00075) and PFS (P = 0.00077). For definitively treated patients, when MTV was analyzed as a binary value above or below the median value, 2-year PFS was 60% versus 39.7% (median PFS 34.9 vs. 11.9 months) and 2-year OS was 79.7% versus 33.3% (median OS 41.9 vs. 18.9 months), respectively (log-rank P = 0.12 for PFS and P = 0.066 for OS). When MTV was analyzed as a continuous variable, multivariate Cox proportional hazards analysis demonstrated a trend to worse PFS (hazard ratio [HR] = 1.31; P = 0.12) and significantly worse OS (HR = 1.53; P = 0.018) with increasing MTV after controlling for known prognostic variables.

CONCLUSION

Tumor burden as assessed by MTV yields prognostic information on survival beyond that of established prognostic factors in patients with NSCLC treated definitively.

Can FDG PET predict radiation treatment outcome in head and neck cancer? Results of a prospective study

Purpose

In head and neck cancer (HNC) various treatment strategies have been developed to improve outcome, but selecting patients for these intensified treatments remains difficult. Therefore, identification of novel pretreatment assays to predict outcome is of interest. In HNC there are indications that pretreatment tumour ¹⁸F-fluorodeoxyglucose (FDG) uptake may be an independent prognostic factor. The aim of this study was to assess the prognostic value of FDG uptake and CT-based and FDG PET-based primary tumour volume measurements in patients with HNC treated with (chemo)radiotherapy.

Methods

A total of 77 patients with stage II–IV HNC who were eligible for definitive (chemo)radiotherapy underwent coregistered pretreatment CT and FDG PET. The gross tumour volume of the primary tumour was determined on the CT (GTV_CT) and FDG PET scans. Five PET segmentation methods were applied: interpreting FDG PET visually (PET_VIS), applying an isocontour at a standardized uptake value (SUV) of 2.5 (PET_2.5), using fixed thresholds of 40% and 50% (PET_40%, PET_50%) of the maximum intratumoral FDG activity (SUV_MAX) and applying an adaptive threshold based on the signal-to-background (PET_SBR). Mean FDG uptake for each PET-based volume was recorded (SUV_mean). Subsequently, to determine the metabolic volume, the integrated SUV was calculated as the product of PET-based volume and SUV_mean. All these variables were analysed as potential predictors of local control (LC), regional recurrence-free survival (RRFS), distant metastasis-free survival (DMFS), disease-free survival (DFS) and overall survival (OS).

Results

In oral cavity/oropharynx tumours PET_VIS was the only volume-based method able to predict LC. Both PET_VIS and GTV_CT were able to predict DMFS, DFS and OS in these subsites. Integrated SUVs were associated with LC, DMFS, DFS and OS, while SUV_mean and SUV_MAX were not. In hypopharyngeal/laryngeal tumours none of the variables was associated with outcome.

Conclusion

There is no role yet for pretreatment FDG PET as a predictor of (chemo)radiotherapy outcome in HNC in daily routine. However, this potential application needs further exploration, focusing both on FDG PET-based primary tumour volume, integrated SUV and SUV_MAX of the primary tumour.

Prognostic Value of Metabolic Tumor Volume Measured by (18)F-FDG PET/CT in Locally Advanced Head and Neck Squamous Cell Carcinomas Treated by Surgery

PURPOSE

We assessed the prognostic value of metabolic tumor volume (MTV) measured using(18)F-fluorodeoxyglucose (FDG) positron emission tomography/computed tomography (PET/CT) inpatients with locally advanced head and neck squamous cell carcinoma (HNSCC).

METHODS

We retrospectively reviewed 56 patients (51 men, five women; mean age 56.0 ± 8.8years) who had locally advanced HNSCC and underwent FDG PET/CT for initial evaluation. All patients had surgical resection and radiotherapy with or without concurrent chemotherapy. The peak standardized uptake value (SUVpeak) and MTV of the target lesion, including primary HNSCC andmetastatic cervical lymph nodes, were measured from FDG PET/CT images. We compared SUVpeak, MTV, and clinicopathologic variables such as age, Eastern Cooperative Oncology Group (ECOG) performance status, pN stage, pT stage, TNM stage, histologic grade and treatment modality to disease-free survival (DFS) and overall survival (OS).

RESULTS

On the initial FDG PET/CT scans, the median SUVpeak was 7.8 (range, 1.8-19.0) and MTV was17.0 cm(3) (range, 0.1-131.0 cm(3)). The estimated 2-year DFS and OS rates were 67.2% and 81.8%. The cutoff points of SUVpeak 6.2 and MTV 20.7 cm(3) were the best discriminative values for predicting clinical outcome. MTV and ECOG performance status were significantly related to DFS and OS on univariate and multivariate analyses (p < 0.05).

CONCLUSION

The MTV obtained from initial FDG PET/CT scan is a significant prognostic factor for disease recurrence and mortality in locally advanced HNSCC treated with surgery and radiotherapy with or without chemotherapy.

Early FDG PET at 10 or 20 Gy under chemoradiotherapy is prognostic for locoregional control and overall survival in patients with head and neck cancer

PURPOSE

Our study aimed to explore the optimal timing as well as the most appropriate prognostic parameter of (18)F-fluorodeoxyglucose positron emission tomography (FDG PET) during chemoradiotherapy (CRT) for an early prediction of outcome for patients with head and neck squamous cell carcinoma (HNSCC).

METHODS

Serial PET data (before and three times during CRT) of 37 patients with advanced stage HNSCC, receiving combined CRT between 2005 and 2009, were evaluated. The maximum standardized uptake value (SUV(max)), the average SUV (SUV(mean)) and the gross tumour volume determined by FDG PET (GTV PET), based on a source to background algorithm, were analysed. Stratified actuarial analysis was performed for overall survival (OS), disease-free survival (DFS) and locoregional control (LRC). The median follow-up time was 26 months (range 8-50).

RESULTS

For all patients, OS was 51%, DFS 44% and LRC 55% after 2 years. The 2-year OS (88%) and 2-year LRC (88%) were higher for patients whose SUV(max) of the primary tumour decreased 50% or more from the beginning (0 Gy) to week 1 or 2 (10 or 20 Gy) of CRT (ΔSUV(max10/20) ≥ 50%) than for patients with ΔSUV(max20) < 50% (2-year OS = 38%; p = 0.02; 2-year LRC 40%; p = 0.06). A pretreatment GTV PET below the median of 10.2 ml predicted a better 2-year OS (34% for GTV PET ≥ 10.2 ml vs 83% for GTV PET < 10.2 ml; p = 0.02).

CONCLUSION

The decrease of SUV(max) from before (0 Gy) to week 1 or 2 (10 or 20 Gy) of CRT is a potential prognostic marker for patients with HNSCC. Because GTV PET depends on the applied method of analysis, we suggest the use of SUV(max), especially ΔSUV(max10/20), for an early estimation of therapy outcome. Confirmatory studies are warranted.

18F-FDG PET or PET-CT to evaluate prognosis for head and neck cancer: a meta-analysis

PURPOSE

The purpose of this meta-analysis was to evaluate the prognostic value of standard uptake value (SUV) from serial Fluorine-18-fluorodeoxyglucose positron emission tomography/computed tomography ((18)F-FDG PET/CT) in patients with head and neck cancer.

METHODS

We searched for articles limited to head and neck cancer, dealt with the impact of SUV on survival and published in English. The endpoints were disease-free survival (DFS), overall survival (OS), and local control (LC). Two reviewers extracted data independently.

RESULTS

Thirty-five studies were identified; of which, 26 studies involving 1,415 patients met the inclusion criteria. Pooled survival data suggested better DFS, OS, and LC in patients with low SUV of pre-treatment, and the odds ratio (OR) was 0.23, 0.24, and 0.27, respectively. Patients having tumors with low SUV of post-treatment also had significantly better DFS (OR = 0.17) and OS (OR = 0.28) than those with high SUV.

CONCLUSIONS

The present meta-analysis showed that (18)F-FDG uptake, as measured by the SUV before treatment and metabolic response after treatment, are valuable for predicting long-term survival in head and neck cancer. High (18)F-FDG uptake may be useful for identifying patients requiring more aggressive treatment.

The Prognostic Value of the Metabolic Tumor Volume in FIGO stage IA to IIB Cervical Cancer for Tumor Recurrence: Measured by F-18 FDG PET/CT

PURPOSE

The purpose of this study was to evaluate the prognostic value of the metabolic tumor volume (MTV), in FIGO stage IA-IIB cervical cancer patients, measured by F-18 fluorodeoxyglucose positron emission tomography (FDG-PET) imaging.

METHODS

Forty-five patients with invasive cervical cancer who underwent FDG-PET imaging were recruited. Metabolically active tumor regions were delineated on the pretreatment FDG-PET scans by encompassing regions equal to or greater than an standardized uptake value (SUV) of 40% of the peak tumor intensity. The relationship of the metabolic tumor volume (MTV) to the disease-free survival was analyzed. The MTV of the cervical cancer was compared with pathological and clinical prognostic factors, including lymph node metastasis, parametrial invasion, the depth of invasion, resection margins, tumor differentiation and FIGO stages.

RESULTS

Cox proportional hazard regression analysis showed that the MTV was a significant independent predictor of recurrence of cervical cancer (p = 0.027). Patients with an MTV of >20 cm(3) had a significantly reduced disease-free survival compared with patients with an MTV ≤ 20 cm(3) (p = 0.029). The correlation of the MTV with traditional prognostic factors showed significantly higher values in patients that were lymph node (LN) metastasis positive (p = 0.028) and parametrial invasion positive (p = 0.022). The MTV significantly differed among the groups according to tumor differentiation (p = 0.0319) and FIGO stage (p = 0.001).

CONCLUSION

The MTV measured by FDG-PET was an independent prognostic factor for tumor recurrence in patients with stage IA-IIB cervical cancer. These findings must be confirmed by large population based prospective studies.

[Patients with malignancies of the oro- and hypopharynx as well as the larynx. Significance/importance of oncological aftercare consultation]

The necessity of a long-time, closely monitored, well-structured, personal and time-consuming aftercare consultation is still discussed controversially. Based on the analysis of our oncological patients with tumours of the pharynx and larynx in the period from 1999-2000 we want to emphasize that after treatment is of vital importance. Besides the main focus of oncology on the early detection of recurrent tumours, distant metastases and second primary tumours as well as a fast interdisciplinary and mostly multimodal treatment planning, consultation is also a central point of reference and coordination site for rehabilitation, psycho-oncology and quality assurance of treatment. Last but not least consultation serves for purposes of continuous data collection and oncological epidemiology.