Do clinical characteristics and metabolic markers detected on positron emission tomography/computerized tomography associate with persistent disease in patients with in-operable cervical cancer?

Tumor and metastatic lymph nodes metabolic activity on 18F-FDG-PET/CT to predict progression-free survival in locally advanced cervical cancer

OBJECTIVE

The present study investigated the predictive diseases progression value of preoperative fluorodeoxyglucose (FDG) positron emission tomography/computed tomography (PET/CT) in patients with local advanced cervical cancer (LACC).

METHODS

In total, 267 patients [median age 58 (range: 27-85) years old] with LACC underwent 18F-FDG PET/CT prior to any treatment. The maximum standardized uptake values (SUVmax), metabolic tumor volume (MTV), and total lesion glycolysis (TLG) of the primary lesion and metastatic lymph nodes were measured on PET/CT and correlated with clinicopathological features and progression-free survival (PFS).

RESULTS

The median follow-up was 36.52 (range: 3.09-61.29) months. During the observation period, 80 (30.0%) patients exhibited disease progression. Univariate analysis showed that FIGO stage, concurrent chemoradiotherapy (CRT), serum level of carcinoembryonic antigen (CEA) and squamous cell carcinoma antigen (SCC-Ag), primary tumor MTV (pMTV) and TLG (pTLG), lymph nodes SUVmax (nSUVmax) and TLG (nTLG), and total metabolic activity (sMTV, sTLG) were associated with PFS. nSUVmax ≥ 5.29, CEA ≥ 7.11 ng/ml and deficiency of concurrent CRT were independent risk factor for PFS (p = 0.006, p = 0.008, p = 0.014). The 3-year PFS for patients with high nSUVmax were 42.2% compared to 56.3% for low nSUVmax values.

CONCLUSION

Pretreatment cervical and lymph nodes metabolic parameters were associated with PFS 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.

Optimal method for metabolic tumour volume assessment of cervical cancers with inter-observer agreement on [18F]-fluoro-deoxy-glucose positron emission tomography with computed tomography

PURPOSE

Cervical cancer metabolic tumour volume (MTV) derived from [18F]-FDG PET/CT has a role in prognostication and therapy planning. There is no standard method of outlining MTV on [18F]-FDG PET/CT. The aim of this study was to assess the optimal method to outline primary cervical tumours on [18F]-FDG PET/CT using MRI-derived tumour volumes as the reference standard.

METHODS

81 consecutive cervical cancer patients with pre-treatment staging MRI and [18F]-FDG PET/CT imaging were included. MRI volumes were compared with different PET segmentation methods. Method 1 measured MTVs at different SUVmax thresholds ranging from 20 to 60% (MTV20-MTV60) with bladder masking and manual adjustment when required. Method 2 created an isocontour around the tumour prior to different SUVmax thresholds being applied. Method 3 used an automated gradient method. Inter-observer agreement of MTV, following manual adjustment when required, was recorded.

RESULTS

For method 1, the MTV25 and MTV30 were closest to the MRI volumes for both readers (mean percentage change from MRI volume of 2.9% and 13.4% for MTV25 and - 13.1% and - 2.0% for MTV30 for readers 1 and 2). 70% of lesions required manual adjustment at MTV25 compared with 45% at MTV30. There was excellent inter-observer agreement between MTV30 to MTV60 (ICC ranged from 0.898-0.976 with narrow 95% confidence intervals (CIs)) and moderate agreement at lower thresholds (ICC estimates of 0.534 and 0.617, respectively for the MTV20 and MTV25 with wide 95% CIs). Bladder masking was performed in 86% of cases overall. For method 2, excellent correlation was demonstrated at MTV25 and MTV30 (mean % change from MRI volume of -3.9% and - 8.6% for MTV25 and - 16.9% and 19% for MTV30 for readers 1 and 2, respectively). This method also demonstrated excellent ICC across all thresholds with no manual adjustment. Method 3 demonstrated excellent ICC of 0.96 (95% CI 0.94-0.97) but had a mean percentage difference from the MRI volume of - 19.1 and - 18.2% for readers 1 and 2, respectively. 21% required manual adjustment for both readers.

CONCLUSION

MTV30 provides the optimal correlation with MRI volume taking into consideration the excellent inter-reader agreement and less requirement for manual adjustment.

Value of integrated PET-IVIM MRI in predicting lymphovascular space invasion in cervical cancer without lymphatic metastasis

PURPOSE

To evaluate the contributory value of positron emission tomography (PET)-intravoxel incoherent motion (IVIM) magnetic resonance imaging (MRI) in the prediction of lymphovascular space invasion (LVSI) in patients with cervical cancer without lymphatic metastasis.

MATERIALS AND METHODS

A total of 90 patients with cervical cancer without signs of lymph node metastasis on PET/MRI were enrolled in this study. The tumours were classified into LVSI-positive (n = 25) and LVSI-negative (n = 65) groups according to postoperative pathology. The PET-derived parameters (SUV_max, SUV_mean, metabolic tumour volume (MTV) and total lesion glycolysis (TLG)) and IVIM-derived parameters (ADC_mean, ADC_min, D_mean, D_min, f, D* and gross tumour volume (GTV)) between the two groups were evaluated using a Student's t test (Mann-Whitney U test for variables with a nonnormal distribution) and receiver operating characteristic (ROC) curves. The optimal combination of PET/MR parameters for predicting LVSI was investigated using univariate and multivariate logistic regression models and evaluated by ROC curves. The optimal cutoff threshold values corresponded to the maximal values of the Youden index. A control model was established using 1000 bootstrapped samples, for which the performance was validated using calibration curves and ROC curves.

RESULTS

PET-derived parameters (SUV_max, SUV_mean, MTV, TLG) and IVIM MRI-derived parameters (D_min, ADC_min, GTV) were significantly different between patients with and without LVSI (P < 0.05). Logistic analyses showed that a combination of TLG and D_min had the strongest predictive value for LVSI diagnosis (area under the curve (AUC), 0.861; sensitivity, 80.00; specificity, 86.15; P < 0.001). The optimal cutoff threshold values for D_min and TLG were 0.58 × 10^-3 mm²/s and 66.68 g/cm³, respectively. The verification model showed the combination of TLG and D_min had the strongest predictive value, and its ROC curve and calibration curve showed good accuracy (AUC, 0.878) and consistency.

CONCLUSIONS

The combination of TLG and D_min may be the best indicator for predicting LVSI in cervical cancer without lymphatic metastasis.

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.

Tumor total lesion glycolysis and number of positive pelvic lymph nodes on pretreatment positron emission tomography/computed tomography (PET/CT) predict survival in patients with locally advanced cervical cancer

OBJECTIVE

The aim of this study was to investigate the prognostic value of metabolic parameters obtained at pretreatment [18F]fluoro-2-deoxy-D-glucose positron emission tomography/computed tomography ([18F]FDG PET/CT) in patients with locally advanced cervical cancer. We hypothesize that these metabolic parameters could optimize the treatment decision and thus favor the outcome of patients suffering locally advanced cervical cancer.

METHODS

Patients with locally advanced cervical cancer underwent pretreatment PET/CT. Standard uptake values (maximum, mean, peak), metabolic tumor volume, and total lesion glycolysis were measured in the tumor and in the hypermetabolic pelvic lymph nodes. The relationship between clinical, pathological, and PET/CT metabolic parameters with recurrence-free survival and overall survival was assessed by Cox regression analysis.

RESULTS

115 patients with a median age of 52 years (range 23-77) presented with locally advanced cervical cancer. After a mean follow-up of 33.0 months after initiation of therapy, 26 patients (22.6%) recurred of which 17 patients had distant metastasis; 18 (15.7%) patients died. Recurrence-free survival at 2 and 5 years was 79.2% and 72.2%, respectively. The total lesion glycolysis of the tumor and the delay between diagnosis and treatment were significantly associated with recurrence-free survival in the multivariate analysis (HR 1.00, p=0.004, and HR 2.04, p=0.02, respectively). Only the total lesion glycolysis of the tumor ≥373.54 (HR 2.49, 95% CI 1.15 to 5.38; p=0.02) remained significant after log rank testing. Overall survival at 2 and 5 years was 91.7% and 68.8%, respectively. The number of PET-positive pelvic lymph nodes was the only independent prognostic factor for overall survival in the multivariate analysis (HR 1.43, 95% CI 1.13 to 1.81; p=0.003).

CONCLUSION

Tumor total lesion glycolysis and the number of positive pelvic lymph nodes on pretreatment PET/CT appear to be independent prognostic factors for recurrence and survival in patients with locally advanced cervical cancer. This may help to select patients who may benefit from therapeutic optimization and closer surveillance.

Combinative evaluation of primary tumor and lymph nodes to predict pelvic lymphatic metastasis in cervical cancer: an integrated PET-IVIM MRI study

Background

The aim of this study was to evaluate the value of combining pelvic lymph node and tumor characteristics on positron emission tomography-intravoxel incoherent motion magnetic resonance (PET-IVIM MR) imaging for predicting lymph node metastasis in patients with cervical cancer, especially in those with negative lymph nodes on PET.

Methods

The medical records of 95 patients with cervical cancer who underwent surgical resection with pelvic lymph node dissection were evaluated. The patients were divided into negative and positive groups according to postoperative pathologic lymph node diagnosis, and comparisons of the PET and IVIM-derived parameters between the two groups were performed. Univariate and multivariate analyses were performed to construct a predictive model of lymph node metastasis.

Results

For all patients, tumor SUV_max, TLG, D_min, PET and MRI for lymph node diagnosis showed significant differences between patients with and without confirmed lymph node metastasis. Univariate and multivariate logistic analysis showed that the combination of tumor TLG, D_min and PET for lymph node diagnosis had the strongest predictive value (AUC 0.913, p < 0.001). For patients with PET-negative lymph nodes, SUV_max, SUV_mean, MTV, TLG, and D_min showed significant between-group differences, and univariate and multivariate logistic analysis showed that TLG had the strongest predictive value.

Conclusions

The combination of tumorTLG, D_min and PET for lymph node diagnosis is a powerful prognostic factor for all patients. TLG has the best predictive performance in patients with PET negative lymph nodes.

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.

FDG-PET Imaging in Cervical Cancer

FDG-PET/CT has an established role in the initial staging of locally advanced cervical cancers, particularly in evaluation of nodal disease and distant metastases. It is common practice to perform FDG-PET/CT 3 months postcompletion of chemoradiotherapy as it can predict outcome and be used to tailor management, including adjuvant therapy and follow-up. It is also routinely used prior to pelvic exenterative surgery to ensure there is no disease outside the pelvis. There is growing evidence that FDG-PET-derived parameters are prognostic and could potentially be used to tailor therapy. This review outlines the use of FDG-PET/CT imaging in cervical cancer.

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.

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.

Prognostic Value of Pretreatment Metabolic PET Parameters in Cervical Cancer Patients With Metabolic Complete Response After Concurrent Chemoradiotherapy

PURPOSE

Cervical cancer may recur after concurrent chemoradiotherapy (CCRT), even in patients with metabolic complete response (mCR) on post-CCRT F-FDG PET. We retrospectively analyzed the value of metabolic parameters, measured by pretreatment PET, as prognostic factors for predicting recurrence and death in cervical cancer patients with mCR.

METHODS

In 61 patients who reached mCR on post-CCRT, metabolic PET parameters including SUVmax, metabolic tumor volume (MTV), and total lesion glycolysis (TLG) of the primary tumors, as well as those of the metastatic lymph nodes, were measured by pre-CCRT PET. Total MTV and total TLG were also measured from primary tumors and metastatic lymph nodes. Survival analyses for disease-free survival (DFS) and overall survival (OS) were performed.

RESULTS

Eleven patients (18.0%) presented with recurrence of cervical cancer, and 12 (19.7%) died during follow-up. SUVmax, MTV, TLG of metastatic lymph nodes, and total TLG could significantly predict DFS, and nodal SUVmax could predict OS. Para-aortic lymph node metastasis also significantly correlated with both DFS and OS. In multivariate analysis, nodal SUVmax and para-aortic lymph nodes metastasis were prognostic factors for DFS, and the best predictor was nodal SUVmax. For OS, nodal MTV and para-aortic lymph node metastasis were significant prognostic factors in multivariate analysis, and the best predictor was para-aortic lymph node metastasis.

CONCLUSIONS

Metabolic PET parameters, SUVmax or MTV values of metastatic lymph nodes, may be surrogate prognostic markers for recurrence or death in patients with locally advanced cervical cancer who reached mCR after definitive CCRT.

A comparison of two imaging modalities for detecting lymphatic nodal spread in radiochemotherapy of locally advanced cervical cancer

Background and purpose

Material and methods

Results

Conclusions

Prognostic Value of Volume-Based Metabolic Parameters Obtained by 18F-FDG-PET/CT in Patients With Locally Advanced Squamous Cell Cervical Carcinoma

OBJECTIVE

The aim of the study was to assess the prognostic impact of volume-based metabolic F-fluorodeoxyglucose-positron emission tomography/ computed tomography (F-FDG-PET/CT) parameters in patients with stage IB-IVA squamous cell cervical carcinoma (SCCC).

MATERIALS AND METHODS

We reviewed the pretreatment F-FDG-PET/CT records of 67 patients with stage IB-IVA SCCC. The maximum standardized uptake value (SUVmax) of the primary tumor (PSUVmax), highest SUVmax of the whole malignant lesions (WSUVmax), metabolic tumor volume (MTV) of the primary tumor (PMTV), MTV of the whole malignant lesion (WMTV), total lesion glycolysis (TLG) of primary tumor (PTLG), and TLG of the whole malignant lesion (WTLG) were obtained. Univariate and multivariate analyses were performed to assess the predictive values of metabolic parameters.

RESULTS

Twenty-nine patients showed disease progression and 21 patients died during follow-up. In univariate analysis, positive lymph node, WSUVmax of greater than 11, WMTV of greater than 63 cm, and WTLG of greater than 373 adversely affected the progression-free survival (P = 0.004, 0.045, 0.023, and 0.005, respectively). A positive lymph node, WSUVmax of greater than 12, WMTV of greater than 68 cm, and WTLG of greater than 373 significantly adversely affected overall survival (P = 0.002, 0.032, 0.015, and 0.006, respectively). In multivariate analysis, independent prognostic factor for progression-free survival was WTLG (relative risk = 2.384, 95% confidence interval = 1.095-5.187, P = 0.029). Independent prognostic factors for overall survival was WTLG (relative risk = 2.763; 95% confidence interval = 1.107-6.896, P = 0.029).

CONCLUSIONS

Preliminary results indicated that pretreatment WTLG measured by F-FDG-PET/CT could independently predict survival in patients with locally advanced SCCC.

(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.

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 (SUVmax), SUVmean, 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, SUVmax, MTV, SUVmean 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.

Prognostic Impact of Pretreatment Fluorodeoxyglucose Positron Emission Tomography/Computed Tomography SUVmax in Patients With Locally Advanced Cervical Cancer

OBJECTIVE

The aim of this study was to investigate the impact of SUVmax fluorodeoxyglucose positron emission tomography/computed tomography (FDG-PET/CT) measured in the primary tumor, pelvic and para-aortic node with disease-free survival (DFS) and overall survival (OS) in patients with locally advanced cervical cancer.

METHODS AND MATERIALS

A total of 92 patients with histological diagnosis of locally advanced cervical cancer are treated with radiochemotherapy plus brachytherapy boost from January 2008 to April 2014 in our Institution. A pretreatment FDG-PET/CT for staging and radiotherapy planning was performed, and the value of SUVmax measured in primary tumor and positive nodes was related to DFS and OS.

RESULTS

Univariate analysis showed that DFS is related to FDG-PET/CT positive para-aortic nodes (P = 0.01), International Federation of Gynecology and Obstetrics (FIGO) stage of disease (P = 0.01), and primary tumor SUVmax (P = 0.02), and OS is related to positive para-aortic nodes (P = 0.01) and primary tumor SUVmax (P = 0.02).In multivariate analysis, DFS is modified by FDG-PET/CT positive para-aortic lymph nodes, stage and high T SUVmax (P = 0.02; P = 0.003; P = 0.04), but the only worse prognostic factor of OS is the high SUVmax in the primary tumor (P = 0.01).

CONCLUSIONS

We found that T SUVmax, stage, and para-aortic lymph node status assessed by FDG-PET were independent prognostic factors of DFS, whereas only T SUVmax correlated with OS.

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.

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.

(18)F Sodium Fluoride PET/CT in Patients with Prostate Cancer: Quantification of Normal Tissues, Benign Degenerative Lesions, and Malignant Lesions

Understanding the range and variability of normal, benign degenerative, and malignant ¹⁸F sodium fluoride (¹⁸F NaF) positron emission tomography/computed tomography (PET/CT) uptake is important in influencing clinical interpretation. Further, it is essential for the development of realistic semiautomated quantification techniques and simulation models. The purpose of this study is to determine the range of these values in a clinically relevant patient population with prostate cancer. ¹⁸F NaF PET/CT scans were analyzed in patients with prostate cancer (n = 47) referred for evaluation of bone metastases. Mean and maximum standardized uptake values [SUVs (SUV_mean and SUV_max)] were made in normal background regions (n = 470) including soft tissues (liver, aorta, bladder, adipose, brain, and paraspinal muscle) and osseous structures (T12 vertebral body, femoral diaphyseal cortex, femoral head medullary space, and ribs). Degenerative joint disease (DJD; n = 281) and bone metastases (n = 159) were identified and quantified by an experienced reader using all scan information including coregistered CT. For normal bone regions, the highest ¹⁸F NaF PET SUV_mean occurred in T12 (6.8 ± 1.4) and it also showed the lowest coefficient of variation (cv = 21%). For normal soft tissues, paraspinal muscles showed very low SUV_mean (0.70 ± 0.11) and also showed the lowest variability (cv = 16%). Average SUV_mean in metastatic lesions is higher than uptake in benign degenerative lesions but values showed a wide variance and overlapping values (16.3 ± 13 vs 11.1 ± 3.8; P < 0.00001). The normal ¹⁸F NaF PET uptake values for prostate cancer patients in normal background, benign degenerative disease, and osseous metastases are comparable to those reported for a general population with a wide variety of diagnoses. These normal ranges, specifically for prostate cancer patients, will aid in clinical interpretation and also help to establish the basis of normal limits in a semiautomated data analysis algorithm.

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.