Prognostic significance of volume-based metabolic parameters in uterine cervical cancer determined using 18F-fluorodeoxyglucose positron emission tomography

[18F]FDG PET/CT Radiomics in Cervical Cancer: A Systematic Review

Background/Objectives: Cervical cancer is a significant global health concern, with high incidence and mortality rates, especially in less-developed regions. [18F]FDG PET/CT is now indicated at various stages of management, but its analysis is essentially based on SUVmax, a measure of [18F]FDG uptake. Radiomics, by extracting a multitude of parameters, promises to improve the diagnostic and prognostic performance of the examination. However, studies remain heterogeneous, both in terms of patient numbers and methods, so a synthesis is needed. Methods: This systematic review was conducted following PRISMA-P guidelines and registered in PROSPERO (CRD42024584123). Eligible studies on PET/CT radiomics in cervical cancer were identified through PubMed and Scopus and assessed for quality using the Radiomics Quality Score (RQS v2.0), with data extraction focusing on study design, population characteristics, radiomic methods, and model performances. Results: The review identified 22 studies on radiomics in cervical cancer, 19 of which focused specifically on locally advanced cervical cancer (LACC) and assessed various clinical outcomes, such as survival, relapse, treatment response, and lymph node involvement prediction. They reported significant associations between prognostic indicators and radiomic features, indicating the potential of radiomics to improve the predictive accuracy for patient outcomes in LACC; however, the overall quality of the studies was relatively moderate, with a median RQS of 12/36. Conclusions: While radiomic analysis in cervical cancer presents promising opportunities for survival prediction and personalized care, further well-designed studies are essential to provide stronger evidence for its clinical utility.

Application of PET/MRI in Gynecologic Malignancies

The diagnosis, treatment, and management of gynecologic malignancies benefit from both positron emission tomography/computed tomography (PET/CT) and MRI. PET/CT provides important information on the local extent of disease as well as diffuse metastatic involvement. MRI offers soft tissue delineation and loco-regional disease involvement. The combination of these two technologies is key in diagnosis, treatment planning, and evaluating treatment response in gynecological malignancies. This review aims to assess the performance of PET/MRI in gynecologic cancer patients and outlines the technical challenges and clinical advantages of PET/MR systems when specifically applied to gynecologic malignancies.

Advancements in dendritic cell vaccination: enhancing efficacy and optimizing combinatorial strategies for the treatment of glioblastoma

Glioblastomas (GBM) are highly invasive, malignant primary brain tumors. The overall prognosis is poor, and management of GBMs remains a formidable challenge, necessitating novel therapeutic strategies such as dendritic cell vaccinations (DCVs). While many early clinical trials demonstrate an induction of an antitumoral immune response, outcomes are mixed and dependent on numerous factors that vary between trials. Optimization of DCVs is essential; the selection of GBM-specific antigens and the utilization of 18F-fludeoxyglucose Positron Emission Tomography (FDG-PET) may add significant value and ultimately improve outcomes for patients undergoing treatment for glioblastoma. This review provides an overview of the mechanism of DCV, assesses previous clinical trials, and discusses future strategies for the integration of DCV into glioblastoma treatment protocols. To conclude, the review discusses challenges associated with the use of DCVs and highlights the potential of integrating DCV with standard therapies.

Correlation between [68Ga]Ga-FAPI-46 PET Imaging and HIF-1α Immunohistochemical Analysis in Cervical Cancer: Proof-of-Concept

Hypoxia leads to changes in tumor microenvironment (upregulated CAFs) with resultant aggressiveness. A key factor in the physiological response to hypoxia is hypoxia-inducible factor-1alpha (HIF-1α). [68Ga]Ga-FAPI PET imaging has been demonstrated in various cancer types. We hypothesized that [68Ga]Ga-FAPI PET may be used as an indirect tracer for mapping hypoxia by correlating the image findings to pathological analysis of HIF-1α expression. The [68Ga]Ga-FAPI PET/CT scans of women with cancer of the cervix were reviewed and the maximum and mean standardized uptake value (SUVmax and SUVmean) and FAPI tumor volume (FAPI-TV) were documented. Correlation analysis was performed between PET-derived parameters and immunohistochemical staining as well as between PET-derived parameters and the presence of metastasis. Ten women were included. All patients demonstrated tracer uptake in the primary site or region of the primary. All patients had lymph node metastases while only six patients had distant visceral or skeletal metastases. The mean SUVmax, SUVmean, and FAPI-TV was 18.89, 6.88, and 195.66 cm3, respectively. The average FAPI-TV for patients with additional sites of metastases was higher than those without. Immunohistochemistry revealed varying intensities of HIF-1α expression in all tested samples. There was a positive correlation between the presence of skeletal metastases and staining for HIF-1α (r=0.80;p=0.017). The presence of skeletal metastasis was correlated to the HIF-1⍺ staining (percentage distribution). Furthermore, the FAPI-TV was a better predictor of metastatic disease than the SUVmax.

The value of metabolic parameters and textural analysis in predicting prognosis in locally advanced cervical cancer treated with chemoradiotherapy

Objective

The aim of the study was to assess the impact of clinical and metabolic parameters derived from ¹⁸F-FDG PET/CT (positron emission tomography–computed tomography) in patients with locally advanced cervical cancer (LACC) on prognosis.

Methods

Patients with LACC of stage IB2-IVA treated by primary radiochemotherapy followed by brachytherapy were enrolled in this retrospective study. Indexes derived from standardized uptake value (SUV), metabolic tumor volume (MTV), total lesion glycolysis (TLG), and textural features of the primary tumor were measured for each patient. Overall survival (OS) and recurrence-free survival (RFS) rates were calculated according to Kaplan–Meier and survival curves were compared using the log-rank test. Uni- and multivariate analyses were performed using the Cox regression model.

Results

A total of 116 patients were included. Median follow-up was 58 months (range: 1–129). A total of 36 (31%) patients died. Five-year OS and RFS rates were 69 and 60%, respectively. Univariate analyses indicated that FIGO stage, the presence of hydronephrosis, high CYFRA 21.1 levels, and textural features had a significant impact on OS and RFS. MTV as well as SCC-Ag concentration were also significantly associated with OS. On multivariate analysis, the presence of hydronephrosis, CYFRA 21.1, and sphericity were independent prognostics factors for OS and RFS. Also, SCC-Ag level, MTV, and GLZLM (gray-level zone length matrix) ZLNU (zone length non-uniformity) were significantly associated with OS.

Conclusion

Classical prognostic factors and tumor heterogeneity on pretreatment PET/CT were significantly associated with prognosis in patients with LACC.

The Role of the Metabolic Parameters of 18F-FDG PET/CT in Patients With Locally Advanced Cervical Cancer

Purpose

To evaluate the role of the pre-treatment cervical and lymph node (LN) metabolic parameters of ¹⁸F-fluorodeoxyglucose positron emission tomography-computed tomography (¹⁸F-FDG PET/CT) for locally advanced cervical cancer (LACC) patients receiving concurrent chemoradiotherapy or radiotherapy.

Methods

we reviewed 125 consecutive patients with LACC who underwent pre-treatment ¹⁸F-FDG PET/CT examination and concurrent chemoradiotherapy or radiotherapy from February 2010 to December 2015 at our institute. The mean standardized uptake value (SUVmean), maximum standardized uptake value (SUVmax), metabolic tumor volume (MTV), and total lesion glycolysis (TLG) of cervical lesion and lymph node (LN) were recorded. Receiver operator characteristic curve, C-index, Kaplan-Meier method, and Cox proportional hazards models were performed.

Results

The median follow-up was 62 months (range, 4-114 months). For 125 included patients with cervical cancer, the 5-year overall survival (OS), disease-free survival (DFS), local control (LC) and distant metastasis-free survival (DMFS) rates were 83.6%, 75.1%, 92.3% and 79.9%, respectively. Cervical MTV (c-index 0.59-0.61) and cervical TLG (c-index 0.60-0.62) values calculated with a threshold of 40% SUVmax presented stronger prediction capability than cervical SUVmean (c-index 0.51-0.58) and cervical SUVmax (c-index 0.53-0.57) for OS, DFS, LC, and DMFS. In univariate analysis, cervical TLG ≥ 113.4 had worse DFS and DMFS. Cervical MTV ≥ 18.3 cm³ had worse OS and DMFS. In multivariate analysis, cervical TLG ≥ 113.4 implied worse OS, DFS, and DMFS. In either univariate or multivariate analyses, cervical SUVmean and cervical SUVmax had no statistically significant correlation with OS, DFS, LC and DMFS. For 55 cervical cancer patients with positive LN, LN SUVmax presented strongest prediction capability for OS (c-index = 0.79), DFS (c-index = 0.72), LC (c-index = 0.62), and DMFS (c-index = 0.79). In multivariate analysis, LN SUVmax remained significant biomarker linked to OS, DFS, and DMFS.

Conclusion

Pre-treatment cervical and LN metabolic parameters were associated with survival outcomes in patients with LACC. In our study, we found that pre-treatment cervical TLG and LN SUVmax may be important prognostic biomarkers for OS, DFS, and DMFS. However, further prospective studies with a large number of patients are required to evaluate the value of the metabolic parameters in survival outcomes prediction.

Markers of Prognosis for Early Stage Cervical Cancer Patients (Stage IB1, IB2) Undergoing Surgical Treatment

Background

For individuals with cervical cancer, large tumor volume, lymph node metastasis, distant metastasis, and parauterine infiltration are usually associated with a poor prognosis. Individuals with stage 1B1 and 1B2 cervical cancer usually do not have these unfavorable prognostic factors. Once the disease progresses, the prognosis becomes extremely poor. Therefore, investigating the prognostic markers of these cervical cancer patients is necessary for treatment.

Methods

This retrospective study included 95 cervical cancer patients treated with surgery. The patients were divided into progressor and non-progressor groups according to postoperative follow-up results. T-test (or Mann−Whitney U test), chi-squared test (or Fisher’s exact test) and receiver operating characteristic (ROC) curves were used to evaluate imaging, hematology, and clinicopathological index differences between the two groups. Cox analysis was performed to select the independent markers of progression-free survival (PFS) when developing the nomogram. Validation of the nomogram was performed with 1000 bootstrapped samples. The performance of the nomogram was validated with ROC curves, generated calibration curves, and Kaplan-Meier and decision curve analysis (DCA).

Results

Cervical stromal invasion depth, lymphovascular space invasion (LVSI), human papilloma virus (HPV-16), Glut1, D-dimer, SUVmax and SUVpeak showed significant differences between the two groups. Multivariate Cox proportional hazard model showed SUVpeak (p = 0.012), and HPV-16 (p = 0.007) were independent risk factors and were used to develop the nomogram for predicting PFS. The ROC curves, Kaplan-Meier method, calibration curves and DCA indicated satisfactory accuracy, agreement, and clinical usefulness, respectively.

Conclusions

SUVpeak level (≥7.63 g/cm3) and HPV-16 negative status before surgery were associated with worse PFS for patients with cervical cancer. Based on this result, we constructed the nomogram and showed satisfactory performance. Clinically, individualized clinical decision-making can be performed on patients based on this result.

Pretreatment [18F]FDG PET/CT Prognostic Factors in Patients with Squamous Cell Cervical Carcinoma FIGO IIIC1

PURPOSE

This study aims to determine whether semiquantitative parameters obtained from both the primary tumor and metastatic pelvic lymph nodes (PLN) diagnosed in fluoro-18-deoxy-glucose positron emission tomography (FDG-PET-CT) are associated with disease-free survival (DFS), local control (LC), distant metastasis-free survival (DMFS) and overall survival (OS) in patients with locally advanced squamous cervical cancer (LACC) and metastatic pelvic lymph nodes.

MATERIALS

Retrospective analysis was performed on 93 female patients with FIGO IIIC1. The median age was 53 years (27-75). The PET parameters both in the primary tumor and metastatic pelvic lymph nodes, including SUVmax, SUVmean, TLG, MTV, heterogeneity, along with clinical variables, before radical cisplatin-based radiochemotherapy (RCT) were analyzed. The p-values < 0.05 were considered statistically significant.

RESULTS

Median follow-up was 38 months (4.5-92.6). Three years and five years OS were 75% and 70% respectively. Patients with SUVmax above 12.6, SUVmean above 7.6 and with TLG in tumors >245.7 lived longer (p < 0.05). The higher SUVmax or SUVmean reduced increased DMFS (HR 0.3 95%CI 0.56-0.96 and 0.59 95%CI 0.37-0.93). The clinical factors and other FDG PET CT parameters were not found to be statistically relevant in terms of OS, DFS, DM and LC.

CONCLUSIONS

This study is the first report showing that in LACC patient population with PLN involvement treated with definitive RCT, high SUVmean, SUVmax and TLG of the primary tumor in FDG-PET-CT were linked with longer OS. Lower SUVmean and SUVmax were linked with shorter DMFS. None of the clinical factors and the nodal FDG-PET-CT parameters influenced the outcome.

Metabolic Parameters as Biomarkers of Response to Immunotherapy and Prognosis in Non-Small Cell Lung Cancer (NSCLC): A Real World Experience

Immune-checkpoint inhibitors (ICIs) have been proven to have great efficacy in non-small cell lung cancer (NSCLC) as single agents or in combination therapy, being capable to induce deep and durable remission. However, severe adverse events may occur and about 40% of patients do not benefit from the treatment. Predictive factors of response to ICIs are needed in order to customize treatment. The aim of this study is to evaluate the correlation between quantitative positron emission tomography (PET) parameters defined before starting ICI therapy and responses to treatment and patient outcome. We retrospectively analyzed 92 NSCLC patients treated with nivolumab, pembrolizumab or atezolizumab. Basal PET/computed tomography (CT) scan parameters (whole-body metabolic tumor volume-wMTV, total lesion glycolysis-wTLG, higher standardized uptake volume maximum and mean-SUVmax and SUVmean) were calculated for each patient and correlated with outcomes. Patients who achieved disease control (complete response + partial response + stable disease) had significantly lower MTV median values than patients who had not (progressive disease) (77 vs. 160.2, p = 0.039). Furthermore, patients with MTV and TLG values lower than the median values had improved OS compared to patients with higher MTV and TLG (p = 0.03 and 0.05, respectively). No relation was found between the other parameters and outcome. In conclusion, baseline metabolic tumor burden, measured with MTV, might be an independent predictor of treatment response to ICI and a prognostic biomarker in NSCLC patients.

Prediction of treatment response in patients with locally advanced cervical cancer using midtreatment PET/MRI during concurrent chemoradiotherapy

PURPOSE

We aimed to find metabolic, functional or morphological characteristics of the tumor predicting failure to achieve complete metabolic remission (CMR) by the midtreatment PET/MRI (positron emission tomography/magnetic resonance imaging) in cervical cancer patients.

METHODS

We evaluated 66 patients treated between August 2015 and November 2019 who underwent pretreatment staging, subsequent midtreatment evaluation, and definitive restaging 3 months after completing the whole treatment, all using PET/MRI. The pretreatment parameters (pre-SUVmax, pre-SUVmean, pre-MTV, pre-MTV‑S, pre-TLG, pre-TLG‑S [SUV: standard uptake value, MTV: metabolic tumor volume, TLG: total lesion glycolysis]), and the midtreatment parameters at week 5 during chemoradiotherapy (mid-SUVmax, mid-SUVmean, mid-MTV, mid-MTV‑S, mid-TLG and mid-TLG-S) were recorded. The value of ADC (apparent diffusion coefficient) was also measured. Furthermore, we recorded absolute and relative changes in all parameters-∆ and ∆%. We divided the whole group of patients into "responders" (CMR) and "non-responders" (non-CMR), and compared them on the basis of the parameters from pre-PET/MRI and mid-PET/MRI.

RESULTS

A statistically significant difference in the evaluated parameters between responders and non-responders was found for the following parameters: mid-MTV, mid-TLG, mid-TLG‑S, mid-MTV‑S, mid-tumor size, and ∆%SUVmax. According to the ROC (receiver operating characteristic) analysis, mid-MTV‑S showed the best albeit moderate discrimination ability for the prediction of non-CMR. Significant mutual correlations of all variables, in particular between mid-MTV‑S and mid-TLG‑S and between mid-MTV and mid-TLG, were found (all p < 0.05).

CONCLUSION

Our study confirmed that when using the midtreatment PET/MRI we are able to identify metabolic parameters having the discrimination ability for the prediction of non-CMR. In particular mid-MTV‑S, mid-MTV, mid-tumor size, mid-TLG‑S, mid-TLG and ∆%SUVmax.

Quantitative PET Imaging and Clinical Parameters as Predictive Factors for Patients With Cervical Carcinoma: Implications of a Prediction Model Generated Using Multi-Objective Support Vector Machine Learning

Purpose:

Quantitative features from pre-treatment positron emission tomography (PET) have been used to predict treatment outcomes for patients with cervical carcinoma. The purpose of this study is to use quantitative PET imaging features and clinical parameters to construct a multi-objective machine learning predictive model.

Materials/Methods:

Seventy-five patients with stage IB2-IVA disease treated at our institution from 2009–2012 were analyzed. Models predicting locoregional and distant failure were generated using clinical parameters (age, race, stage, histology, tumor size, nodal status) and imaging features (12 textural, 9 intensity, 8 geometric features, 2 additional imaging features) from pre-treatment PET. Model features were selected based on a multi-objective evolutionary algorithm to maximize specificity given a fixed moderately high sensitivity using support vector machine learning methods. Model 1 used clinical parameters only (C), Model 2 used imaging features only (I), and Model 3 used clinical and imaging features (C+I). Sensitivity, specificity, area under a receiver-operating characteristic curve (AUC), and p-values were compared to assess ability to predict locoregional and distant failure.

Results:

C+I had the highest performance for both locoregional failure (AUC 0.84, p < 0.01; specificity: 0.86; sensitivity: 0.79) and distant failure (AUC 0.75, p < 0.01; specificity: 0.75; sensitivity: 0.75).

Conclusions:

Based on a moderately high fixed sensitivity and optimized for specificity, the model using both clinical parameters and imaging features (C+I) had the best performance in predicting both locoregional failure and distant failure.

PET/MRI in Cervical Cancer: Associations Between Imaging Biomarkers and Tumor Stage, Disease Progression, and Overall Survival

BACKGROUND

Positron emission tomography (PET)/MRI biomarkers have been shown to have prognostic significance in patients with cervical cancer. Their associations with progression-free survival (PFS) and overall survival (OS) merit further investigation.

PURPOSE

To evaluate the association between PET/MRI biomarkers and tumor stage, PFS, and OS in patients with cervical cancer.

STUDY TYPE

Prospective cohort study.

POPULATION

In all, 54 patients with newly diagnosed cervical cancer and measurable tumors (>1 cm) were included in the image analysis.

FIELD STRENGTH/SEQUENCE

3.0T integrated PET/MRI including diffusion-weighted echo-planar imaging (b = 50 and 1000 s/mm² ) and [18F]fluorodeoxyglucose PET.

ASSESSMENT

Two radiologists measured the minimum and mean apparent diffusion coefficient (ADC_min and ADC_mean ), maximum standardized uptake value (SUV_max ), metabolic tumor volume (MTV), and total lesion glycolysis (TLG) of the primary tumors.

STATISTICAL TESTS

A Mann-Whitney U-test was used to evaluate the association between the imaging biomarkers and tumor stage. A Cox proportional hazards model was used to assess the relationships between the imaging biomarkers and survival.

RESULTS

In advanced tumors (T ≥ 1b2, M1, stage ≥ IB3), ADC_min was significantly lower and MTV, TLG, MTV/ADC_min , and TLG/ADC_min were significantly higher (P values between <0.001 and 0.036). In N1 tumors, ADC_min was significantly lower and MTV and MTV/ADC_min were significantly higher (P values between 0.005 and 0.016). In survival analysis, SUV_max was an independent predictor of PFS (hazard ratio [HR] = 4.57, P < 0.05), and ADC_min was an independent predictor of OS (HR = 0.02, P < 0.05). In subgroup analysis of patients with different stages, MTV/ADC_min was a predictor of PFS in stage I disease (P = 0.003), ADC_min (P = 0.038), and MTV (P = 0.020) in stage II, SUV_max (P = 0.006), and TLG (P = 0.006) in stage IV; and ADC_min was a predictor of OS in stage III disease (P = 0.008).

DATA CONCLUSION

PET/MRI biomarkers of cervical cancer are associated with tumor stage and survival. SUV_max and ADC_min are independent predictors of PFS and OS, respectively.

LEVEL OF EVIDENCE

1 TECHNICAL EFFICACY: 3.

Changes on Midchemoradiation Therapy Fluorodeoxyglucose Positron Emission Tomography for Cervical Cancer Are Associated with Prognosis

PURPOSE

To assess whether radiographic and metabolic changes on midchemoradiation therapy (CRT) fluorodeoxyglucose positron emission tomography and computed tomography (FDG-PET/CT) for cervical cancer predict outcome.

METHODS AND MATERIALS

Women with International Federation of Gynecology and Obstetrics stage IB1-IVB cervical cancer treated with concurrent cisplatin-based CRT and brachytherapy were enrolled on a single-institution prospective clinical trial; FDG-PET/CT was obtained before CRT and at 30 to 36 Gy. Max and mean standard uptake values, metabolic tumor volume, and total lesion glycolysis (TLG) for the primary tumor and clinically involved lymph nodes from the pre-CRT and intra-CRT FDG-PET/CT were recorded. Clinical endpoints analyzed include overall survival (OS), disease-free survival (DFS), and rates of cervical recurrence (CR), nodal recurrence (NR), and distant metastasis (DM). FDG-PET/CT variables and other prognostic factors associated with clinical endpoints were identified via univariate Cox proportional hazards modeling and competing risk analysis.

RESULTS

Thirty women were enrolled from 2012 to 2016. After a median follow-up of 24 months, 2-year rates of OS, DFS, DM, NR, and CR were 68% (95% confidence interval [CI], 51%-85%), 44% (95% CI, 26%-63%), 42% (95% CI, 23%-59%), 14% (95% CI, 4%-30%), and 10% (95% CI, 2%-24%), respectively. Intra-PET metrics and TLG across all PET scans were most consistently associated with OS, DFS, DM, and NR on univariate analysis. Intra-CRT TLG was associated with OS (hazard ratio [HR] 1.35; 95% CI, 1.15-1.55; P = .001), DFS (HR 1.19; 95% CI, 1.04-1.34; P = .018), and NR (HR 1.25; 95% CI, 1.10-1.40; P = .002). No absolute or relative changes between parameters of baseline and mid-CRT FDG-PET/CT were associated with disease outcomes on univariate analysis, with the exception of relative change in mean standard uptake values and CR (P = .004).

CONCLUSIONS

In this group of patients with high-risk cervical cancer treated with CRT and brachytherapy, TLG and metabolic tumor volume on intra-CRT FDG-PET/CT was associated with OS. These metrics may provide an early signal for selective treatment intensification with either dose escalation or adjuvant chemotherapy.

Multiparametric PET/MR (PET and MR-IVIM) for the evaluation of early treatment response and prediction of tumor recurrence in patients with locally advanced cervical cancer

OBJECTIVES

To assess the value of ¹⁸F-FDG PET and MR-IVIM parameters before and during concurrent chemoradiotherapy (CCRT) for evaluating early treatment response and predicting tumor recurrence in patients with locally advanced cervical cancer (LACC) using a hybrid PET/MR scanner.

METHODS

Fifty-one patients with LACC underwent pelvic PET/MR scans with an IVIM sequence at two time-points (pretreatment [pre] and midtreatment [mid]). Pre- and mid-PET parameters (SUV_max, MTV, TLG) and IVIM parameters (D, F, D*) and their percentage changes (Δ%SUV_max, Δ%MTV, Δ%TLG, Δ%D, Δ%F, Δ%D*) were calculated. We selected independent imaging parameters and built a combined prediction model incorporating imaging parameters and clinicopathological risk factors. The performance of the combinative evaluation for tumor early shrinkage rates (TESR) and the prediction model for tumor recurrence was assessed.

RESULTS

Thirty-two patients were classified into the good response (GR) group with TESR ≥ 50%, and 19 patients were categorized into the poor response (PR) group with TESR < 50%. Δ%D (p = 0.013) and Δ%F (p = 0.006) are independently related to TESR with superior combined diagnostic ability (AUC = 0.901). Pre-TLG, Δ%D, and suspicious lymph node metastasis (SLNM) were selected for the construction of the combined prediction model. The model for identifying the patients with high risk of tumor recurrence reached a moderate predictive ability and good stability with c-index of 0.764 (95% CI, 0.672-0.855).

CONCLUSION

The combined prediction model based on pretreatment PET metabolic parameter (pre-TLG), IVIM-D percentage changes, and LNs status provides great potential to identify the LACC patients with high risk of recurrence at early stage of CCRT.

KEY POINTS

• PET/MR plus IVIM offers various complementary information for LACC. • IVIM-D and IVIM-F percentage changes are independently related to tumor early shrinkage rates. • The combined prediction model can help identify the LACC patients with high risk of tumor recurrence.

Strain elastography as an early predictor of long-term prognosis in patients with locally advanced cervical cancers treated with concurrent chemoradiotherapy

OBJECTIVE

To explore the value of strain elastography as an early predictor of long-term prognosis in patients with locally advanced cervical cancers treated with concurrent chemoradiotherapy (CCRT).

METHODS

Strain elastography examinations were performed on 45 patients with locally advanced cervical cancers at 3 time points: prior to CCRT, and at 1 and 2 weeks after the start of CCRT. The maximum tumor diameter (D_max), strain ratio (SR), and their percentage changes (ΔD_max and ΔSR) were calculated to predict long-term prognosis. Based on the results of physical examinations, Papanicolaou test, and pelvic magnetic resonance imaging, we classified patients into two groups: responders (complete remission) and non-responders (sustained disease, recurrence, or death).

RESULTS

After a median follow-up of 30 months (range, 12-36 months), 36 of 45 (80%) patients were disease free. The D_max as well as ΔD_max at 2 weeks during CCRT was able to predict the responder outcomes, with an area-under-the-curve (AUC) of 0.733 and 0.731, respectively. Furthermore, significant differences in SR and ΔSR at 1 and 2 weeks during therapy were shown between the responder and non-responder groups (all p < 0.05), and ΔSR at 2 weeks during CCRT presented with the highest AUC (0.91), yielding 88.9% sensitivity and 88.9% specificity with a selected cutoff value.

CONCLUSIONS

Strain elastography may be useful as an early predictor of long-term outcomes after CCRT for patients with cervical cancer.

KEY POINTS

• The D _maxas well as ΔD _maxat 2 weeks during CCRT can predict the responder outcomes. • The elastography parameters (SR and ΔSR) exhibited predictive values of favorable response after therapy initiation. • ΔSR at 2 weeks during CCRT held the best predictive value for the responder outcomes.

Volumetric assessment of apparent diffusion coefficient predicts outcome following chemoradiation for cervical cancer

OBJECTIVE

To determine the utility of volumetric diffusion weighted imaging (DWI) compared to other clinical factors for predicting recurrence and survival in cervical cancer patients treated with definitive chemoradiation.

METHODS AND MATERIALS

We retrospectively studied cervical cancer patients treated with definitive chemoradiation between 2009-2013 at a single institution with a baseline MRI with DWI and 18F-FDG positron emission tomography/computed tomography (FDG-PET) scan. To identify clinical and imaging metrics correlated with survival and recurrence endpoints, variable importance values were calculated from random forest models. To provide clinically relevant threshold values, recursive partitioning analysis dichotomized patients into potential risk groups based on selected metrics. Cox's proportional hazard models assessed the effect of clinical and imaging factors on survival endpoints.

RESULTS

Ninety-three patients were included in the analysis (median age 50 years). At a median follow-up of 35.6 months, 32 patients (34%) had disease recurrence. In the best multivariate model including clinical and imaging parameters, 90th percentile ADC < 1.917 was the only significantly associated factor with worse progression free survival (PFS). Overall survival, PFS, and distant metastasis free survival (DMFS) were significantly different between patient groups divided on 90th percentile ADC with threshold of 1.917 × 10-3 mm2/s and MRI volume with threshold of 18.9 cc (P = 0.037, P = 0.0002, P = 0.001). High MRI volume and low ADC were associated with worse clinical outcomes.

CONCLUSIONS

Volumetric 90th percentile ADC value of the primary tumor on pretreatment MRI was a significant predictor of PFS and DMFS in cervical cancer patients, independent of established clinical factors and SUV on FDG-PET.

Metabolic parameters with different thresholds for evaluating tumor recurrence and their correlations with hematological parameters in locally advanced squamous cell cervical carcinoma: an observational 18F-FDG PET/CT study

Background

Positron emission tomography (PET) parameters for a combination of the primary tumor and suspicious metastatic lymph nodes (SMLNs) appear to be more potential than those for the primary tumor alone for evaluating tumor recurrence in locally advanced cervical carcinoma (LACC), while the optimal threshold has not been determined. This study investigated the optimal PET parameters and percentage of SUV_max (%SUV_max) thresholds for tumor recurrence evaluation, and the relationship with hematological parameters in patients with LACC treated with concurrent chemoradiotherapy (CCRT).

Methods

Eighty-nine patients with advanced squamous cell cervical carcinoma (SCCC) scheduled for CCRT underwent pretreatment whole body PET/CT scans. We analyzed PET parameters including maximum standardized uptake value (SUV_max), metabolic tumor volume (MTV), and total lesion glycolysis (TLG) of the primary tumor (SUV_max-P, MTV-P, TLG-P) and the combination of the primary tumor and SMLNs (SUV_max-C, MTV-C, TLG-C). The association between PET parameters with different %SUV_max threshold and recurrence-free survival (RFS), and the correlations between PET parameters and hematological parameters including squamous cell carcinoma antigen (SCC-ag), neutrophil-lymphocyte ratio (NLR), platelet-lymphocyte ratio (PLR) and hemoglobin (Hb) were evaluated.

Results

The optimal threshold for evaluating tumor recurrence was 50%SUV_max, and the optimal PET parameter was MTV-C with the 50%SUV_max threshold (MTV-C_50%) (c-index =0.752). Multivariate analysis indicated that MTV-C_50% [hazard ratio (HR), 1.065; P<0.001], NLR (HR, 1.195; P=0.045) and SMLNs (HR, 2.225; P=0.003) were independent risk factors for RFS. MTV and TLG with most of %SUV_max thresholds had slight-to-moderate correlations with SCC-ag, NLR and PLR. For SCC-ag, MTV-C55% (r=0.500; P<0.001) had the highest correlation coefficient among all parameters. For NLR and PLR, MTV-C_50% (r=0.637 and r=0.515, respectively; P<0.001 for both correlations) received the highest correlation coefficient.

Conclusions

The MTV-C estimated by using a 50%SUV_max threshold, which is related to systemic inflammatory response biomarker (NLR and PLR), can be used as an optimal PET parameter associated with tumor recurrence of LACC.

The efficacy of pretreatment and after treatment 18F-FDG PET/CT metabolic parameters in patients with locally advanced squamous cell cervical cancer

OBJECTIVES

Cervical cancer is one of the main causes of cancer death worldwide. Fluorine-18-fluorodeoxyglucose (F-FDG) PET/computed tomography (PET/CT) has been playing an increasingly important role in staging and monitoring treatment response in the disease. In the current study, we investigated metabolic F-FDG PET/CT parameters among patients with locally advanced squamous cell cervical cancer treated with concurrent chemoradiotherapy for predicting disease-free survival (DFS).

PATIENTS AND METHODS

Forty-four patients with biopsy-proven locally advanced squamous cell cervical cancer were included in the study. Pretreatment and after treatment F-FDG PET/CT metabolic parameters [metabolic tumor volume, tumor lesion glycolysis, maximum standard uptake value (SUVmax)] for the primary tumor area and/or pelvic/para-aortic lymph nodes and also accompanying distant metastases were analyzed. Treatment response was divided into four groups according to a post-treatment F-FDG PET/CT scan.

RESULTS

For all patients, the 3-year DFS was 79%. Pretreatment primary tumor SUVmax and tumor lesion glycolysis, pelvic lymph node SUVmax, and pretreatment para-aortic lymph node SUVmax were significant prognostic factors for DFS with different cut-off values. In contrast, for metabolic tumor volume-T1, there was no statistical significance for DFS.

CONCLUSION

F-FDG PET/CT cut-off values may help clinicians with their treatment planning and follow-up in locally advanced squamous cell cervical cancer patients.

Chemoradiotherapy for locally advanced cervix cancer without aortic lymph node involvement: can we consider metabolic parameters of pretherapeutic FDG-PET/CT for treatment tailoring?

PURPOSE

Aim of the study was to assess impact of pretherapeutic FDG-PET/CT metabolic parameters on response to chemoradiotherapy (CRT) and survival in locally advanced cervical cancer (LACC) patients without paraaortic lymph node involvement.

METHODS

LACC patients treated with CRT without macrometastatic involvement after paraaortic surgical staging were included. All patients had received at least 45 Gy radiotherapy and five cycles of platinum-based chemotherapy. High-risk histologies were excluded. Two senior nuclear physician experts in gynaecologic oncology reviewed all PET/CT exams, and extracted tumor SUVmax, MTV, and TLG (standardized uptake value, metabolic tumor volume, and total lesion glycolysis respectively). Response to CRT was assessed with a pelvic MRI done after 45 Gy. Medical charts were reviewed for clinical, pathology, and survival data.

RESULTS

Ninety-three patients were included in the study. The overall survival (OS) rates at 2 and 5 years were 83.0% [95%CI: 72.5-89.8] and 71.2% [57.5-81.2] respectively. The RFS rates at 2 and 5 years were 72.5% [61.5-80.9] and 64.4% [52.3-74.2] respectively. Higher cervical SUVmax and TLG were significantly associated with poor response to CRT. In multivariate analysis, cervical SUVmax was the main predictive factor for OS.

CONCLUSION

Cervical tumor SUVmax was demonstrated to be a non-invasive prognostic biomarker for response to treatment and survival in LACC patients without paraaortic involvement. SUVmax and other PET/CT metabolic parameters require further prospective investigation to help tailoring of local treatment.

Evaluation of 18F-FDG PET/CT parameters for reflection of aggressiveness and prediction of prognosis in early-stage cervical cancer

PURPOSE

The aim of this study was to investigate the value of five typical fluorine-18-fluorodeoxyglucose PET/computed tomography (CT) parameters (including SUVmax, SUVmean, SUVpeak, MTV and TLG) in the reflecting aggressiveness and predicting prognosis in patients with early-stage cervical cancer.

PATIENTS AND METHODS

Our study enrolled 85 primary cervical cancer patients who underwent preoperative fluorine-18-fluorodeoxyglucose PET/CT scans. We investigated the association of five parameters derived from PET/CT with clinicopathological characteristics. Immunohistochemistry was utilized to evaluate the expression of glucose transporter protein-1 (GLUT-1), TP53-induced glycolysis and apoptosis regulator (TIGAR), and vascular endothelial growth factor (VEGF), and the correlation between PET/CT parameters and the expression of GLUT-1, TIGAR, and VEGF was analyzed. In addition, we also investigated the correlation between disease-free survival of cervical cancer patients and PET/CT parameters.

RESULTS

The mean peak standardized uptake value (SUV)peak showed significant differences between all three International Federation of Gynecology and Obstetrics stages (P<0.001-0.032). The patients with lymph node metastasis had significantly higher SUVpeak, metabolic tumor volume (MTV), and total lesion glycolysis (TLG) compared with those with the absence of lymph node metastasis (P=0.038, 0.024, and 0.010, respectively). All the five parameters showed an association with tumor size and cervical stromal invasion depth. Immunohistochemistry results indicated that the SUVpeak showed the highest association with the expression of GLUT-1, TIGAR, and VEGF (rs=0.705, P<0.001, rs=-0.466, P<0.001, rs=0.580, P<0.001, respectively) in these five parameters. The survival analysis showed that SUVpeak, MTV, and TLG were correlated with disease-free survival (P=0.042, P<0.001, and P=0.004, respectively).

CONCLUSION

Early-stage cervical cancer with high SUVpeak may reflect more aggressive behavior, and SUVpeak, MTV, and TLG can be used to predict the prognosis of early-stage cervical cancer patients. It may help with the choice of individualized treatment options.

Prognostic values of ADCmean and SUVmax of the primary tumour in cervical cancer patients treated with definitive chemoradiotherapy

We analysed the correlation of ¹⁸F-fluorodeoxyglucose uptake into primary tumours using the maximum standardised uptake value (SUV_max) and the mean apparent diffusion coefficient (ADC_mean) values in magnetic resonance imaging (MRI) with the clinical and pathological factors in patients with cervical cancer who were treated with concurrent chemoradiotherapy. The patients were stratified according to the primary tumour pre-treatment ADC_mean and SUV_max cut-off values. There were significant correlations between the SUV_max of the primary tumour and tumour size, and the treatment response. The correlation between the ADC_mean and FIGO stage, tumour size, and the lymph node metastasis was significant. The SUV_max was significantly and inversely correlated with the ADC_mean for cervical cancer (r = -0.44, p <.001). In the multivariate analysis, the primary tumour ADC_mean, treatment response and the lymph node metastasis emerged as significant independent predictors of both OS and DFS, and of the primary tumour SUV_max for DFS. Tumour size has a borderline significance for OS. High SUV_max and low ADC_mean of the primary tumour are important predictive factors for identifying high-risk patients with cervical cancer who are treated with definitive chemoradiotherapy. These results point to a future role for the diffusion-weighted MRI and for ¹⁸F-fluorodeoxyglucose positron emission tomography, not only in the staging of cervical cancer but as an aid in the selection of an adjuvant treatment regimen after chemoradiotherapy for individual patients. Impact statement What is already known on this subject? A negative correlation between primary tumour SUV_max derived from positron emission tomography (PET/CT) and ADC_min derived from diffusion weighted magnetic resonance imaging (DW-MRI) in various cancer types and cervical cancer has been demonstrated. However, the prognostic value of primary tumour SUV_max and ADC_mean in cervical cancer patients treated with definitive chemoradiotherapy is not well studied yet. What the results of this study add? The patients with high-risk features (larger tumours, extensive stage, lymph node metastasis) had higher primary tumour SUV_max and lower ADC_mean values. Primary tumour ADC_mean and lymph node metastasis emerged as significant independent predictors of both overall and disease-free survival. This study demonstrated that the functional biomarkers delivered from PET-CT and DW-MRI are important in predicting the treatment outcomes in the squamous cell carcinoma of cervix treated with definitive chemoradiotherapy, where clinical and radiological findings are very important, since these patients are not staged surgically. What are the implications of these findings for clinical practice and/or further research? Based on these findings, there may be a future role of DW-MRI and FDG/PET-CT not only in the staging of cervical cancer but as an aid in the selection of an adjuvant treatment regimen after chemoradiotherapy (ChRT) for individual patients.

Prognostic significance of metabolic tumor volume and total lesion glycolysis in patients with advanced cervical carcinoma

AIM

18-Fluoro-2-deoxy-d-glucose positron emission tomography (¹⁸F-FDG PET/CT) is considered to be the most accurate image method of detection of node or distant metastases in cervical cancer. Metabolic tumor volume (MTV) and total lesion glycolysis (TLG) of ¹⁸F-FDG PET/CT are volumetric measurements of tumor cells with increased ¹⁸F-FDG uptake. The prognostic value of MTV and TLG in patients with advanced cervical cancer (ACC) were evaluated.

METHODS

38 patients with ACC from one tertiary university hospital underwent ¹⁸F-FDG PET/CT between June 2009 and December 2015. Clinicopathologic factors and various PET parameters were analyzed to evaluate their relationship with recurrence-free survival (RFS) and overall survival (OS). These parameters were: maximum standardized uptake value (SUVmax), mean standardized uptake value (SUV mean), metabolic tumor volume (MTV), and total lesion glycolysis (TLG) of the primary tumor, of the pelvic nodes, of the paraaortic nodes and the metabolic volume of the metastases if any.

RESULTS

A total of 38 patients with ACC fulfilled the inclusion criteria. All of them underwent a ¹⁸F-FDG PET/CT before definitive chemoradiotherapy. In the univariate analyses higher tumor size, pelvic lymph node metastasis and both MTV and TLG showed a significant association with OS and with RFS (MTV HR=1.55, p=0.011 and TLG HR=1.43, p=0.017 for RFS and MTV HR=1.82, p=0.006 and TLG HR=1.67, p=0.007 for OS).

CONCLUSION

Pretreatment TLG sum and MTV sum seem to be independent prognostic factors for OS and RFS in patients with advanced cervical cancer treated with definitive chemoradiotherapy and they are better than the classic measurement of SUVmax.

(18F)-FDG PET/CT parameters to predict survival and recurrence in patients with locally advanced cervical cancer treated with chemoradiotherapy

PURPOSE

To identify predictive (¹⁸F)-fluorodeoxyglucose (FDG) positron emission tomography (PET)/computed tomography (CT)-based parameters for locoregional control, disease-free survival and overall survival, by testing different thresholds of metabolic tumor volume and total lesion glycolysis in patients with locally-advanced cervical cancer.

PATIENTS AND METHODS

Thirty-seven patients treated with standard chemoirradiation underwent a pretreatment (¹⁸F)-FDG-PET/CT. Using different thresholds of maximum standardized uptake value, the following PET parameters were computed: maximum standardized uptake value, mean standardized uptake value, metabolic tumor volume and total lesion glycolysis for primary tumor and lymph nodes and a new parameter combining the metabolic tumor volume and the distance between lymph nodes and the primary tumor, namely metabolic node distance. Correlation between PET and clinical parameters with clinical outcome (overall survival, disease-free survival, and locoregional control) was assessed using univariate and multivariate analyses (Cox model).

RESULTS

In univariate analyses, PET/CT parameters associated with overall survival and disease-free survival were: metabolic tumor volume and total lesion glycolysis of the primary tumor, total lesion glycolysis of lymph nodes and metabolic node distance. The most predictive threshold segmentation for metabolic tumor volume and total lesion glycolysis was 48% of maximum standardized uptake value for the primary tumor and 30% for the lymph nodes. In multivariate Cox analysis, the total lesion glycolysis of primary tumor 48% and metabolic node distance were the two independent risk factors for overall survival (P<0.01), disease-free survival (P<0.01) and locoregional control (P=0.046).

CONCLUSION

Total lesion glycolysis of primary tumor and distance between the invaded positive lymph node and the primary tumor seem to have the highest predictive value when compared to classical clinical prognostic parameters and may be useful to identify high risk groups at time of diagnosis and to tailor the therapeutic approach in locally-advanced cervical cancer.

Normal Variants and Pitfalls Encountered in PET Assessment of Gynecologic Malignancies

Combined PET/computed tomography is used for oncological indications. PET/computed tomography benefits from the metabolic information of PET and the anatomic localization of computed tomography. The integrated scanner provides data with accurate registration of anatomy and molecular information. Many physiologic conditions, normal variants, and benign lesions within the pelvis and the body can cause confusion and uncertainty. False-negative results owing to low ¹⁸F-fluorodeoxyglucose uptake from the tumor can produce diagnostic challenges and inaccurate conclusions. This article reviews normal variants and potential pitfalls encountered in PET assessment of gynecologic malignancies to provide useful information for the referring and reporting physicians.

Pretreatment metabolic tumour volume and total lesion glycolysis are not independent prognosticators for locally advanced cervical cancer patients treated with chemoradiotherapy

OBJECTIVE

To evaluate the prognostic significance of metabolic parameters derived from fludeoxyglucose (FDG) positron emission tomography (PET)/CT, in cervical cancer patients treated with concurrent chemoradiotherapy.

METHODS

We retrospectively reviewed medical records from 129 biopsy-proven non-metastatic cervical cancer patients treated with external radiotherapy and intracavitary brachytherapy at our department. Correlation between metabolic parameters and tumour characteristics was evaluated. Prognostic factors for survival, local control and distant metastasis were analysed.

RESULTS

The median follow up for all patients and surviving patients was 30.0 months (range, 3.7-94.7 months) and 50.5 months (range, 14.5-94.7 months), respectively. The 2- and 5-year overall survival (OS) and disease-free survival (DFS) rates were 68 42, 54 and 38%, respectively. The maximum standardized uptake value (SUV_max), SUV_mean, metabolic tumour volume (MTV) and total lesion glycolysis were significantly higher in patients with larger tumours (>4 cm) and partial regression or progressive disease after definitive treatment compared to patients with smaller tumour (≤4 cm) and post-treatment complete response. On univariate analysis, stage, lymph node metastasis, tumour size >4 cm, SUV_max, MTV, SUV_mean and total lesion glycolysis were prognostic factors for OS and DFS. On multivariate analysis, only larger tumour and presence of lymph node metastasis were significant prognostic factors for both OS and DFS. Additionally, extensive stage was a significant prognosticator for DFS.

CONCLUSION

Although, metabolic parameters derived from FDG-PET/CT had a prognostic significance in univariate analysis, the significance was lost in multivariate analysis where tumour stage, size and lymph node status were the only independent parameters. Advances in knowledge: The clinical benefit of using FDG-PET/CT metabolic parameters to evaluate the high-risk patients among cervical cancer patients and to eventually change patient management still needs further clarification.

Current Methods to Define Metabolic Tumor Volume in Positron Emission Tomography: Which One is Better?

Numerous methods to segment tumors using ¹⁸F-fluorodeoxyglucose positron emission tomography (FDG PET) have been introduced. Metabolic tumor volume (MTV) refers to the metabolically active volume of the tumor segmented using FDG PET, and has been shown to be useful in predicting patient outcome and in assessing treatment response. Also, tumor segmentation using FDG PET has useful applications in radiotherapy treatment planning. Despite extensive research on MTV showing promising results, MTV is not used in standard clinical practice yet, mainly because there is no consensus on the optimal method to segment tumors in FDG PET images. In this review, we discuss currently available methods to measure MTV using FDG PET, and assess the advantages and disadvantages of the methods.

Comparison of FDG PET metabolic tumour volume versus ADC histogram: prognostic value of tumour treatment response and survival in patients with locally advanced uterine cervical cancer

OBJECTIVE

To evaluate the prognostic utility of volume-based parameters of fluorine-18 fludeoxyglucose positron emission tomography (¹⁸F-FDG PET) and apparent diffusion coefficient (ADC) histogram analysis for tumour response to therapy and event-free survival (EFS) in patients with uterine cervical cancer receiving chemoradiotherapy.

METHODS

The study included 21 patients diagnosed with locally advanced uterine cervical cancer who underwent pre-treatment MRI and ¹⁸F-FDG PET and were treated with concurrent chemoradiotherapy. ¹⁸F-FDG parameters: maximum and mean standardized uptake value; metabolic tumour volume (MTV); total lesion glycolysis (TLG); ADC parameters: maximum, mean and minimum values; percentile ADC values (10-90%); skewness and kurtosis of ADC were measured and compared between the responder and non-responder groups using a Wilcoxon rank-sum test. The Cox regression analysis and Kaplan-Meier survival curves were performed for EFS analysis.

RESULTS

MTV and TLG of the primary tumour were significantly higher in the non-responder group than in the responder group (p = 0.04 and p = 0.01). Applying Cox regression multivariate analysis, MTV [hazard ratio (HR), 4.725; p = 0.036], TLG (HR, 4.725; p = 0.036) and 10-percentile ADC (HR, 5.207; p = 0.048) showed a statistically significant association with EFS. With the optimal cut-off value, the EFS rates above the cut-off value for MTV and TLG were significantly lower than that below the cut-off value (p = 0.002 and p = 0.002).

CONCLUSION

Pre-treatment volume-based quantitative parameters of ¹⁸F-FDG PET may have better potential than ADC histogram for predicting treatment response and EFS in patients with locally advanced cervical cancer. Advances in knowledge: In this study, pre-treatment volume-based quantitative parameters of ¹⁸F-FDG PET had better potential than ADC histogram for predicting treatment response and survival in patients with locally advanced cervical cancer.

Prognostic value of total lesion glycolysis measured by 18F-FDG PET/CT in patients with locally advanced cervical cancer

AIM

The aim of this study was to determine the most relevant parameters of fluorine-18 fluorodeoxyglucose (F-FDG) PET/computed tomography (CT) for predicting recurrence in patients with locally advanced cervical cancer.

MATERIALS AND METHODS

Fifty-six patients diagnosed with International Federation of Gynecology and Obstetrics (FIGO) stage IIB to IVA cervical cancer who underwent F-FDG PET/CT before definitive chemoradiotherapy were retrospectively enrolled. Various PET parameters, namely, maximum standardized uptake value, mean standardized uptake value, metabolic tumor volume, and total lesion glycolysis (TLG) of the primary tumor, were analyzed to evaluate the relationship between these PET parameters and recurrence-free survival (RFS). The cut-off values of PET parameters that showed the best trade-off between sensitivity and specificity for RFS were determined by receiver operating characteristic curve analysis.

RESULTS

The median follow-up was 20 months (range, 6-63 months). Univariate analysis indicated that higher FIGO stage [hazard ratio (HR) 5.606, 95% confidence interval (CI) 1.682-18.68, P=0.005], metabolic tumor volume more than 47.81 cm (HR 6.203, 95% CI 1.351-28.481, P=0.019), and TLG more than 215.02 (HR 11.817, 95% CI 1.518-91.963, P=0.018) were associated with RFS. In multivariate analysis, FIGO stage (HR 4.618, 95% CI 1.295-16.463, P=0.018) and TLG more than 215.02 (HR 10.171, 95% CI 1.246-83.044, P=0.030) were independent predictive factors for RFS. Kaplan-Meier curves for RFS indicated that patients with TLG less than or equal to 215.02 showed better RFS (P=0.003).

CONCLUSION

Pretreatment TLG proved to be an independent prognostic factor for RFS in patients with locally advanced cervical cancer treated by definitive chemoradiotherapy.

PET/CT Response Criteria (European Organization for Research and Treatment of Cancer) Predict Survival Better Than Response Evaluation Criteria in Solid Tumors in Locally Advanced Cervical Cancer Treated With Chemoradiation

PURPOSE

To investigate whether the ratio of SUVs measured with F-FDG PET/CT between pretreatment and posttreatment has prognostic value in patients with locally advanced cervical cancer treated with primary chemoradiation therapy.

METHODS

Cases of locally advanced cervical cancer (International Federation of Gynecology and Obstetrics stages IB1 to IVA) treated with a nonsurgical curative modality (172 cases including chemoradiation or radiation therapy) were reviewed. F-FDG PET/CT parameters, including SUVmax and SUVmean, were evaluated by F-FDG PET/CT performed prior to treatment and 6 weeks after the end of treatment. Metabolic response was evaluated according to the European Organization for Research and Treatment of Cancer guidelines and was compared with radiologic response measured according to the Response Evaluation Criteria In Solid Tumours (RECIST).

RESULTS

In total, 142 patients receiving chemoradiation showed radiologic responses (median 56% decrease in maximal diameter), whereas 160 and 146 patients showed metabolic responses measured with SUVmax and SUVmean, respectively (73% decrease in SUVmax; 48% decrease in SUVmean). Radiologic response and metabolic response were significantly correlated for SUVmax and SUVmean (P = 0.0009; P = 0.0457, respectively). Kaplan-Meier analysis revealed significant differences in overall survival and progression-free survival between the responder and nonresponder groups, based on the European Organization for Research and Treatment of Cancer criteria (both P < 0.001), whereas no significant difference was found when using RECIST criteria (P = 0.058, P = 0.088, respectively).

CONCLUSIONS

F-FDG PET/CT parameters are good prognostic markers for the response of cervical cancer patients to concurrent chemoradiation therapy, as compared with the RECIST criteria.

Diffusion-Weighted Magnetic Resonance Imaging as a Predictor of Outcome in Cervical Cancer After Chemoradiation

PURPOSE

To determine whether apparent diffusion coefficient (ADC) value is predictive of survival after definitive chemoradiation for cervical cancer independent of established imaging and clinical prognostic factors.

METHODS AND MATERIALS

Between 2011 and 2013, the pretreatment MRI scans for 69 patients treated with definitive chemoradiation for newly diagnosed cervical cancer were retrieved. Scans were acquired with a 1.5-T magnetic resonance scanner, including diffusion-weighted imaging sequences. Mean ADC value was measured within a region of interest in the primary cervical cancer on the baseline MRI scan. Baseline tumor maximum standardized uptake value on positron emission tomography/computed tomography was determined by the reading radiologist. Treatment included external beam radiation therapy to the pelvis followed by brachytherapy in 97%, and with concurrent weekly cisplatin in 99% of patients. Univariate and multivariate analyses were done to investigate the association of clinical and imaging variables with disease control and survival endpoints using a Cox proportional hazard test.

RESULTS

Median follow-up was 16.7 months (range, 3.1-44.2 months). The 1-year overall survival, locoregional recurrence-free survival, and disease-free survival rates were 91%, 86%, and 74%, respectively. The median ADC value was 0.941 × 10^-3 mm²/s (range, 0.256-1.508 × 10^-3 mm²/s). The median standardized uptake value in the primary tumor was 15 (range, 6.2-43.4). In multivariate analysis, higher ADC value (hazard ratio [HR] 0.36, 95% confidence interval [CI] 0.15-0.85, P=.02), higher stage (HR 2.4, 95% CI 1.1-5.5, P=.033), and nonsquamous histology (HR 0.23, 95% CI 0.07-0.82, P=.024) were independent predictors of disease-free survival.

CONCLUSIONS

The mean ADC value of the primary tumor on pretreatment MRI was the only imaging feature that was an independent predictor of disease-free survival in cervical cancer patients treated with chemoradiation. Further validation will be needed to determine whether ADC values may prove useful in identifying cervical patients at high risk of recurrence.

Primary tumor SUVmax on preoperative FDG-PET/CT is a prognostic indicator in stage IA2-IIB cervical cancer patients treated with radical hysterectomy

The objective of the present study was to investigate the prognostic value of ¹⁸F-fluoro-2-deoxy-D-glucose (FDG) uptake by primary tumors on positron emission tomography/computed tomography (PET/CT) in surgically resectable cervical cancer. A total of 59 patients with stage IA2-IIB cervical cancer who underwent preoperative FDG-PET/CT, followed by radical hysterectomy and lymphadenectomy, were included in the study. The maximum standardized uptake value (SUV_max) of the primary tumor was measured, and the association between the SUV_max and clinicopathological factors or patient outcomes was analyzed. The SUV_max was significantly higher in patients with an advanced stage, lymph node metastasis, lymph-vascular space involvement and large tumors. The overall survival (OS) and progression-free survival (PFS) of patients with a high SUV_max were significantly lower compared with patients with a low SUV_max, using an optimal cut-off value of 7.36 for OS and 5.59 for PFS obtained from receiver operating characteristic curve analysis. Similarly, OS and PFS in patients with a high SUV_max were significantly lower in 39 patients with stage IB using a cut-off value of 7.90 and 6.69 for OS and PFS, respectively. Finally, multivariate analyses showed that the SUV_max of the primary tumor was an independent prognostic factor for impaired PFS in all patients and those with stage IB alone. These findings demonstrated that a high SUV_max on preoperative PET/CT was correlated with unfavorable clinical outcomes in patients receiving radical hysterectomy, suggesting that the SUV_max of the primary tumor may be a prognostic indicator for surgically-treated, early-stage invasive cervical cancer.

Correlation between histological grade and positron emission tomography parameters in cervical carcinoma

The aim of the present study was to evaluate the changes in cervical cancer glucose metabolism for different levels of cellular differentiation. The metabolic activity was measured by standardized uptake value (SUV), SUV normalized to lean body mass, metabolic tumor volume and total lesion glycolysis using fluorine-18 fluorodeoxyglucose positron emission tomography (PET). A correlation study of these values could be used to facilitate therapeutic choice and to improve clinical practice and outcome. This study considered 32 patients with diagnosed cervical cancers, at different International Federation of Gynecology and Obstetrics stages. Glucose metabolism was assessed by PET examination, and histological specimens were examined to determine their initial grade of differentiation. A correlation study of these values was evaluated. Histological examination showed that all cases were of squamous cell carcinoma. Regarding the differentiation of the tumor, 19 well- to moderately-differentiated tumors and 13 poorly-differentiated tumors were determined. Negative findings for correlations between metabolic parameters and initial grade of histological differentiation were found, and considering that histological grade has been shown to have no consistent prognostic value in cervical cancer treatment, PET imaging could play a significant role in cervical cancer prognosis.

Prognostic Value of Metabolic and Volumetric Parameters of Preoperative FDG-PET/CT in Patients With Resectable Pancreatic Cancer

In this study, we aimed to evaluate prognostic value of metabolic and volumetric parameters measured from F fluorodeoxyglucose-positron emission tomography/computed tomography (FDG-PET/CT) in patients with resectable pancreatic cancer.Fifty-one patients with resectable pancreatic cancer who underwent FDG-PET/CT and curative operation were retrospectively enrolled. The maximum standardized uptake value (SUVmax), metabolic tumor volume (MTV), and total lesion glycolysis (TLG) were measured from FDG-PET/CT. Association between FDG-PET/CT and clinicopathologic parameters was evaluated. The prognostic values of the FDG-PET/CT and clinicopathologic parameters for recurrence-free survival (RFS) and overall survival (OS) were assessed by univariate and multivariate analyses.The 51 enrolled patients were followed up for a median of 21 months (mean ± SD: 23 ± 16 months, range: 1-78 months) with 33 (65%) recurrences and 30 (59%) deaths during the period. SUVmax, MTV, and TLG were associated with Tumor node metastasis (TNM) stage and presence of lymph node metastasis. MTV and TLG were associated with presence of lymphovascular invasion, whereas SUVmax was not. On the univariate analysis, SUVmax, MTV, and TLG were associated with RFS and OS. Also, lymph node metastasis and TNM stage were associated with OS on the univariate analysis. On multivariate analysis, MTV and TLG were independent prognostic factors for RFS and OS. SUVmax was an independent prognostic factor for OS, but not for RFS.Metabolic tumor volume and TLG were independently predictive of RFS and OS in resectable pancreatic cancer. SUVmax was an independent factor for OS, but not for RFS.

Prognostic Value of the Sum of Metabolic Tumor Volume of Primary Tumor and Lymph Nodes Using 18F-FDG PET/CT in Patients With Cervical Cancer

This is an observational study to determine the most relevant parameter of ¹⁸F-fluorodeoxyglucose (FDG) positron emission tomography/computed tomography (PET/CT) for predicting recurrence in cervical cancer. Fifty-six patients with International Federation of Gynecology and Obstetrics (FIGO) stage IIB-IVA cervical cancer who underwent pretreatment ¹⁸F-FDG PET/CT were enrolled. PET parameters including maximum standardized uptake value (SUVmax), metabolic tumor volume (MTV), and total lesion glycolysis (TLG) of both primary tumor and pelvic and/or para-aortic lymph nodes were analyzed. SUVmax-S was defined as the sum of the SUVmax of primary tumor and the higher SUVmax of either pelvic or para-aortic lymph nodes. MTV-S was defined as the sum of the MTV of primary tumor and pelvic and para-aortic lymph nodes. TLG-S was calculated in the same way as MTV-S. We evaluated the relationship between these PET parameters and recurrence-free survival (RFS). Univariate analysis revealed that higher FIGO stage (hazard ratio [HR] = 5.61, 95% confidence interval [CI]: 1.68-18.68, P = 0.005), lymph node metastasis (HR = 3.42, 95% CI: 1.08-10.84, P = 0.037), MTV of primary tumor >47.81 cm³ (HR = 6.20, 95% CI: 1.35-28.48, P = 0.019), TLG of primary tumor >215.02 (HR = 11.82, 95% CI: 1.52-91.96, P = 0.018), MTV-S > 59.01 cm³ (HR = 8.24, 95% CI: 1.80-37.77, P = 0.007), and TLG-S > 224.15 (HR =  13.09, 95% CI: 1.68-101.89, P = 0.014) were associated with RFS. In multivariate analysis, FIGO stage (HR = 4.87, 95% CI: 1.38-17.18, P = 0.014) and MTV-S > 59.01 cm³ (HR = 7.37, 95% CI: 1.54-35.16, P = 0.012) were determined to be independent predictive factors for RFS. Our preliminary results reveal that MTV-S is an independent prognostic factor for RFS in patients with cervical cancer treated by definitive chemoradiotherapy.

Different Prognostic Implications of 18F-FDG PET Between Histological Subtypes in Patients With Cervical Cancer

This study aimed to investigate whether the predictive values of intensity- and volume-based PET parameters are different between histological subtypes in patients with cervical cancer. Ninety patients, 65 with squamous cell carcinoma (SCC) and 25 with non-SCC (NSCC), who underwent pretreatment ¹⁸F-FDG PET/CT and pelvic MRI, were studied retrospectively. In addition to SUVmax and SUVmean, metabolic-tumor-volume (MTV) was determined by thresholding of 40% SUVmax and total-lesion-glycolysis (TLG) was calculated. Clinical factors and PET metabolic indices were compared between SCC and NSCC. Progression-free survival (PFS) and overall survival (OS) were estimated using the Kaplan-Meier method with cut-offs determined by ROC analyses to stratify SCC and NSCC patients separately. Factors associated with survival were assessed with univariate and multivariate analyses using the Cox regression model. No significant differences were observed in clinical factors other than tumor size or ¹⁸F-FDG PET metabolic indices between SCC and NSCC. The Kaplan-Meier estimates of 2-year PFS and OS rates were 60% and 70% for SCC and 40% and 76% for NSCC, respectively. Multivariate analyses showed that MTV and TLG were the independent prognostic factors for PFS and OS in SCC; in contrast, SUVmax was the independent prognostic factor for PFS and OS in NSCC. Metabolic burden (MTV and TLG) could be beneficial for the prognostic prediction of cervical SCC patients; in contrast, metabolic intensity (SUVmax) could be beneficial for the prognostic prediction of NSCC patients. The different prognostic implications might be based on the differences of tissue integrity and histological heterogeneity between SCC and NSCC.

(18)F-FDG PET/CT mean SUV and metabolic tumor volume for mean survival time in non-small cell lung cancer

OBJECTIVE

The study was designed to determine the relationship between survival time of standardized uptake value (SUVmax and SUVmean) and metabolic tumor volume (MTV) in patients with non-small cell lung cancer (NSCLC), and examine the impact of demographic, clinical, and radiological data of these patients on survival.

MATERIALS AND METHODS

We performed a retrospective analysis of the records of 79 patients with NSCLC who presented to our hospital between May 2010 and March 2013, received a final diagnosis, and underwent F-FDG PET/CT for staging. Clinical, radiological, and F-FDG PET/CT parameters with an impact on prognosis such as the SUVmax of the primary tumor as calculated by the volumetric region of interest in the F-FDG PET/CT scans during initial diagnosis, mean SUV of the tumor, and MTV obtained with a threshold of SUVmax greater than 2.5 were recorded and statistically analyzed. A statistical analysis was carried out based on the clinical, radiological, and PET/CT findings of the patients who were divided into 2 groups: survivors and nonsurvivors.

RESULTS

Seventy patients (88.6%) were men, and 9 (11.4%) were women. The mean age was 63.65 ± 11.51 years in the nonsurvivor group (n = 40) versus 62.74 ± 10.60 years in the survivor group (n = 39) (Table 1). The mean survival time from diagnosis was 7.9 ± 6.52 months in the nonsurvivor group versus 14.09 ± 7.41 months in the survivor group. The mean survival time was 12.9 ± 7.9 months for those aged 60 or younger, whereas it was 9.9 ± 7.2 years for those aged 60 or older. According to the Cox regression analysis, higher MTV [relative risk (RR), 1.006; P = 0.03] and mean SUVmax (mSUV) (RR, 1.302; P = 0.03) had a significant impact on shortening of the mean survival time. However, no statistical significance was reached for SUVmax measurements (RR, 0.970; P = 0.39). Furthermore, there was a significant relationship between increased tumor size (<2 cm, 2-4 cm, and ≥4 cm) and shortened mean survival time (P = 0.03).

CONCLUSION

The present study showed that MTV and mSUV of FDG PET/CT scans of the tumor, but not SUVmax, had a significant impact on survival time of patients with NSCLC. Based on this result, we believe that we might have more accurate information about the survival time of our patients if we also evaluate mSUV and MTV in combination with mSUV, which is frequently used for diagnosis and monitoring of patients with NSCLC during our daily practice.

Prognostic significance of volume-based 18F-FDG PET/CT parameter in patients with surgically resected non-small cell lung cancer. Comparison with immunohistochemical biomarkers

AIM

We investigated the prognostic value of volume-based 18F-fluorodeoxyglucose (18F-FDG) positron emission tomography (PET) parameters compared with other factors including several immunohistochemical biomarkers in patients with surgically resected non-small cell lung cancer (NSCLC).

PATIENTS, METHODS

STUDY PARTICIPANTS

290 patients with surgically resected and histopathologically confirmed NSCLC. The maxmum standardized uptake value (SUVmax) and metabolic tumour volume (MTV) of the primary tumour were obtained on 18F-FDG PET/ computed tomography (CT) for initial staging and Ki-67 labeling index (LI), p16, CD31 and cyclin E were evaluated in the primary tumours by immunohistochemical staining. Survival analyses for variables including PET parameters, immunohistochemical biomarker and other clinical factors were performed using the Kaplan-Meier method and Cox proportional hazards regression analysis.

RESULTS

In univariate analyses, tumour stage, tumour size, and MTV were significant prognostic factors for decreased overall survival (OS) and disease-free survival (DFS). Multivariate analyses showed MTV and tumour stage were significant predictors of poor OS (MTV, hazard ratio (HR) = 1.135, p = 0.015; stage, HR = 0.644, p = 0.025) and DFS (MTV, HR = 1.128, p = 0.043; stage, HR = 0.541, p = 0.009).

CONCLUSION

The MTV of primary tumours is a significant prognostic factor for survival along with tumour stage in patients with surgically resected NSCLC. The MTV can predict OS and DFS better than immunohistochemical biomarkers.

Standardized Uptake Value on F-FDG PET/CT as a Prognostic Factor for Survival of Women with Malignant Uterine Tumors: A Meta-Analysis

BACKGROUND

Malignant uterine tumors are crucial in the evaluation of prognosis and the determination of therapeutic strategy.

AIM

This meta-analysis of the available literature aimed to investigate the prognostic value of standardized uptake value (SUV) on fluorine-18-fluorodeoxyglucose positron emission tomography with computed tomography (18F-FDG PET/CT) in uterine malignancies before treatment.

METHODS

The PubMed, MEDLINE and EMBASE databases (1990 to February 2014) were searched to identify studies evaluating SUV on 18F-FDG PET/CT as a prognostic tool for predicting long-term survival in patients with carcinomas of the uterus. The χ2 test and the I2 index were used to estimate heterogeneity among the trials selected in the meta-analysis. The combined hazard ratio was calculated by using a fixed- or random-effects model according to heterogeneity.

RESULTS

Thirteen studies with a total of 1,196 patients were eligible for analysis. High pretreatment SUVmax was significantly associated with poorer event-free survival and overall survival, and the summarized hazard ratio was 3.33 (95% confidence interval 2.34-4.74) and 1.31 (95% confidence interval 1.03-1.67), respectively.

CONCLUSION

The present evidence indicates that SUV on 18F-FDG PET/CT seems to be a valuable prognostic indicator for survival of patients with malignant uterine tumors. Given that 18F-FDG PET/CT can provide both morphologic and functional information, we suggest utilizing PET/CT and its quantitative marker in uterine malignancies before treatment. © 2015 S. Karger AG, Basel.

Volume-based quantitative FDG PET/CT metrics and their association with optimal debulking and progression-free survival in patients with recurrent ovarian cancer undergoing secondary cytoreductive surgery

OBJECTIVE

Our aim was to evaluate the associations between quantitative (18)F-fluorodeoxyglucose positron-emission tomography (FDG-PET) uptake metrics, optimal debulking (OD) and progression-free survival (PFS) in patients with recurrent ovarian cancer undergoing secondary cytoreductive surgery.

METHODS

Fifty-five patients with recurrent ovarian cancer underwent FDG-PET/CT within 90 days prior to surgery. Standardized uptake values (SUVmax), metabolically active tumour volumes (MTV), and total lesion glycolysis (TLG) were measured on PET. Exact logistic regression, Kaplan-Meier curves and the log-rank test were used to assess associations between imaging metrics, OD and PFS.

RESULTS

MTV (p = 0.0025) and TLG (p = 0.0043) were associated with OD; however, there was no significant association between SUVmax and debulking status (p = 0.83). Patients with an MTV above 7.52 mL and/or a TLG above 35.94 g had significantly shorter PFS (p = 0.0191 for MTV and p = 0.0069 for TLG). SUVmax was not significantly related to PFS (p = 0.10). PFS estimates at 3.5 years after surgery were 0.42 for patients with an MTV ≤ 7.52 mL and 0.19 for patients with an MTV > 7.52 mL; 0.46 for patients with a TLG ≤ 35.94 g and 0.15 for patients with a TLG > 35.94 g.

CONCLUSION

FDG-PET metrics that reflect metabolic tumour burden are associated with optimal secondary cytoreductive surgery and progression-free survival in patients with recurrent ovarian cancer.

KEY POINTS

• Both TLG and MTV were associated with optimal tumour debulking. • There was no significant association between SUVmax and tumour debulking status. • Patients with higher MTV and/or TLG had significantly shorter PFS. • SUVmax was not significantly related to PFS.

The role of metabolic tumor volume and total lesion glycolysis on ¹⁸F-FDG PET/CT in the prognosis of epithelial ovarian cancer

PURPOSE

This study assessed the prognostic value of pre-operative 2-[(18)F] fluoro-2-deoxy-D-glucose ((18)F-FDG) positron emission tomography/computed tomography (PET/CT) volumetric parameters, including metabolic tumor volume (MTV) and total lesion glycolysis (TLG), in patients with epithelial ovarian cancer.

METHODS

A total of 175 patients with epithelial ovarian cancer who underwent (18) F-FDG PET/CT and subsequent cytoreductive surgery were retrospectively enrolled. Maximum standardized uptake value (SUVmax) on (18)F-FDG PET/CT was measured for all patients. Because nine patients showed low tumor-to-background uptake ratios, MTV and TLG were measured in 166 patients. Univariate and multivariate analyses were performed to evaluate the prognostic significance of SUVmax, MTV, TLG, and clinicopathological factors for disease progression-free survival.

RESULTS

Disease progressed in 78 (44.6 %) of the 175 patients, and the 2-year disease progression-free survival rate was 57.5 %. Univariate analysis showed that tumor stage, histopathological type, presence of regional lymph node metastasis, residual tumor after cytoreductive surgery, pre-operative serum carbohydrate antigen 125 (CA125) level, SUVmax, MTV, and TLG were significant prognostic factors (p < 0.05). Among these variables, tumor stage (p = 0.0006) and TLG (p = 0.008) independently correlated with disease progression-free survival on multivariate analysis. The disease progression rate was only 2.3 % in stage I-II patients with low TLG (≤100.0), compared to 80.0 % in stage III-IV patients with high TLG (>100.0).

CONCLUSION

Along with tumor stage, TLG is an independent prognostic factor for disease progression after cytoreductive surgery in patients with epithelial ovarian cancer. By combining tumor stage and TLG, one can further stratify the risk of disease progression for patients undergoing cytoreductive surgery.

Pretreatment with the γ-secretase inhibitor DAPT sensitizes drug-resistant ovarian cancer cells to cisplatin by downregulation of Notch signaling

Notch signaling is implicated in ovarian cancer tumorigenesis and inhibition of Notch signaling with γ-secretase inhibitor DAPT resulted in reduction of tumor cell viability and induction of apoptosis in ovarian cancer cells. This study investigated whether DAPT has the same effect on ovarian cancer cells that are resistant to cisplatin and the underlying molecular events. Ovarian cancer cell lines resistant to cisplatin were treated with DAPT, cisplatin or combination for cell viability MTT, flow cytometric cell cycle, ELISA apoptosis and colony formation assays. qRT-PCR and western blotting were used to detect gene expressions. We found that pretreatment of ovarian cancer cisplatin-resistant cell lines with DAPT for 24 h and then with cisplatin for 72 h showed a synergistic antitumor activity in these cell lines, while cisplatin treatment and then addition of DAPT just showed an additive or antagonistic effects on these cisplatin-resistant ovarian cancer cells. Moreover, pretreatment of ovarian cancer cell lines with DAPT and then with cisplatin also inhibited tumor cell colony formation capacity, arrested tumor cells at G2 phase of the cell cycle and induced apoptosis. The cell cycle and apoptosis-related genes, such as cyclin B1, Bcl-2 and caspase-3, were also modulated by the treatment. Pretreatment of ovarian cancer cell lines with DAPT and then with cisplatin downregulated Notch1 and Hes1 expression dose- and time-dependently. The current data demonstrate that DAPT pretreatment was able to sensitize cisplatin-resistant human ovarian cancer cells to cisplatin by downregulation of Notch signaling.