Pre-treatment prediction of early response to chemoradiotherapy by quantitative analysis of baseline staging FDG-PET/CT and MRI in locally advanced cervical cancer

Primary staging with 2[18F]-FDG-PET/CT and -PET/MRI and radiotherapy response evaluation with MRI in uterine cervical cancer: an interim analysis of a prospective clinical trial

BACKGROUND

In uterine cervical cancer (UCC), tumour staging is performed according to the 2018 International Federation of Gynecology and Obstetrics (FIGO) system, where imaging is incorporated, or the more generic Tumour Node Metastasis (TNM) classification. With the technical development in diagnostic imaging, continuous prospective evaluation of the different imaging methods contributing to stage determination is warranted. The aims of this interim study were to (1) evaluate the performance of radiological FIGO (rFIGO) and T staging (rT) with 2-fluorine-18-fluoro-deoxy-glucose (2[18F]-FDG)-positron emission tomography with computed tomography (PET/CT) and with magnetic resonance imaging (PET/MRI), compared to clinical FIGO (cFIGO) and T (cT) staging based on clinical examination and conventional imaging, in treatment-naïve UCC, and to (2) identify possible MRI biomarkers for early treatment response after radiotherapy.

METHODS

Ten consecutive patients with newly diagnosed UCC from the prospective PRODIGYN (Prognostic and Diagnostic Added Value of Medical Imaging in Staging and Treatment Planning of Gynecological Cancer) study (ethical approval number 2022-04207-01; NCT05855941) were included. Study participants underwent 2[18F]FDG-PET/CT and -PET/MRI, and an additional MRI one week after radiotherapy. Agreement between rFIGO and cFIGO was analysed using Cohen's kappa. Differences in rFIGO between 2[18F]FDG-PET/CT and -PET/MRI were evaluated with Wilcoxon signed ranks test, and added value of rFIGO for metastasis assessment was demonstrated with descriptive statistics.

RESULTS

In 2/10 patients, a higher stage was obtained with rFIGO compared to cFIGO, where presence of metastases led to upstaging. In 3/10, rFIGO was lower than cFIGO, and in 5/10 rFIGO and cFIGO were similar. Degree of agreement between rFIGO and cFIGO was poor, (κ = 0.091, p < 0.005) with 2[18F]FDG-PET/CT and (κ = - 0.010, p > 0.05) with FDG/PET/MRI). There was no significant difference between 2[18F]FDG-PET/CT and -PET/MRI for rFIGO (p = 0.18), or rT stage assessment (p = 0.32). MRI-derived tumour volume and apparent diffusion coefficient (ADC) were most affected on MRI one week after radiotherapy.

CONCLUSIONS

Our results indicate that there is an added value of rFIGO staging with 2[18F]FDG-PET/CT and -PET/MRI compared to clinical examination and conventional radiology, for metastasis assessment in treatment-naïve UCC. In early treatment response evaluation with MRI, ADC and tumour volume may be predictive parameters of interest in future prognostic analyses.

TRIAL REGISTRATION

Clinical Trials, NCT05855941. Registered 02 May 2023, https://clinicaltrials.gov/study/NCT05855941?term=NCT05855941&rank=1 .

Utility of interim apparent diffusion coefficient value in predicting treatment response among patients with locally advanced cervical cancer treated with radiotherapy

Background

For locally advanced cervical cancer (LACC), treatment response to radiotherapy (RT) can vary significantly even among those with the same stage classification of International Federation of Gynecology and Obstetrics (FIGO). This study investigated the value of ADC metric for forecasting end-of-treatment outcomes in LACC patients referred for RT.

Methods

Eighty patients with pathologically confirmed cervical squamous cell carcinoma with (SCC) were included in the research. Abdominal or pelvic MRI scans were conducted at least three times for all participants: before RT, three weeks after beginning of RT and approximately two months after RT was finalized. Calculated apparent diffusion coefficient (ADC) values of the LACC include: pre-ADC, interim-ADC, ΔADC and Δ%ADC. Based on Response Evaluation Criteria in Solid Tumors (RECIST) 1.1, subjects were calculated and subsequently categorized into good responders group (complete response) and poor responders group (progressive disease, stable disease or partial response).

Results

Compared to good-responders, subjects of poor-responder group showed significantly lower values of interim-ADC, ΔADC, and Δ%ADC (all P < 0.05). To distinguish between good and poor responders, the optimal cutoff values of interim-ADC, ΔADC, and Δ%ADC were determined to be 1.067 × 10-3 mm2/sec, 0.209 × 10-3 mm2/sec, and 30.74 % using the ROC curve, with corresponding sensitivities of 83.78 %, 86.49 %, 75.68 %, and specificities of 88.37 %, 86.49 %, 75.68 %, respectively. Multivariate logistic regression revealed that the baseline tumor diameter and interim-ADC were significant prognostic factors for treatment response with an odds ratio (OR) of 0.105 (95 % confidence interval [95 % CI] 0.018-0.616) for baseline tumor diameter and 42.896 (95 % CI 8.205-224.262) for interim-ADC.

Conclusion

The interim-ADC value and baseline tumor diameter surfaced as possible indicative factors for predicting the response to RT in patients with LACC.

Application value of artificial intelligence algorithm-based magnetic resonance multi-sequence imaging in staging diagnosis of cervical cancer

The aim of this research is to explore the application value of Deep residual network model (DRN) for deep learning-based multi-sequence magnetic resonance imaging (MRI) in the staging diagnosis of cervical cancer (CC). This research included 90 patients diagnosed with CC between August 2019 and May 2021 at the hospital. After undergoing MRI examination, the clinical staging and surgical pathological staging of patients were conducted. The research then evaluated the results of clinical staging and MRI staging to assess their diagnostic accuracy and correlation. In the staging diagnosis of CC, the feature enhancement layer was added to the DRN model, and the MRI imaging features of CC were used to enhance the image information. The precision, specificity, and sensitivity of the constructed model were analyzed, and then the accuracy of clinical diagnosis staging and MRI staging were compared. As the model constructed DRN in this research was compared with convolutional neural network (CNN) and the classic deep neural network visual geometry group (VGG), the precision was 67.7, 84.9, and 93.6%, respectively. The sensitivity was 70.4, 82.5, and 91.2%, while the specificity was 68.5, 83.8, and 92.2%, respectively. The precision, sensitivity, and specificity of the model were remarkably higher than those of CNN and VGG models (P < 0.05). As the clinical staging and MRI staging of CC were compared, the diagnostic accuracy of MRI was 100%, while that of clinical diagnosis was 83.7%, showing a significant difference between them (P < 0.05). Multi-sequence MRI under intelligent algorithm had a high diagnostic rate for CC staging, deserving a good clinical application value.

Baseline and early response 2-[18F]FDG-PET/MRI for prediction of radiotherapy outcome in uterine cervical squamous cell carcinoma: a prospective single-center observational cohort study

BACKGROUND

Should early response imaging predict tumor response to therapy, personalized treatment adaptations could be feasible to improve outcome or reduce the risk of adverse events. This prospective single-center observational study on 2-fluorine-18-fluoro-deoxy-glucose (2-[18F]FDG) positron-emission tomography/magnetic resonance imaging (PET/MRI) features aims to investigate the association between semantic 2-[18F]FDG-PET/MRI imaging parameters and outcome prediction in uterine cervical squamous cell carcinoma (CSCC) treated with radiotherapy.

RESULTS

Eleven study participants with previously untreated CSCC were examined with 2-[18F]FDG-PET/MRI at baseline and approximately one week after start of curative radiotherapy. All study participants had at least 24 months clinical follow-up. Two patients relapsed during the follow-up period. Reduced tumor size according to visual assessment was present in 9/11 participants (median change in sum of largest diameters (SLD) - 10.4%; range - 2.5 to - 24.6%). The size reduction was less pronounced in the relapse group compared to the no relapse group, with median change in SLD - 4.9%, versus - 10.4%. None of the reductions qualified as significantly reduced or increased in size according to RECIST 1.1., hence all participants were at this stage classified as non-responders/stable disease. Median baseline functional tumor volume (FTV) for the relapse group was 126 cm3, while for the no relapse group 9.3 cm3. Median delta FTV in the relapse group was 50.7 cm3, representing an actual increase in metabolically active volume, while median delta FTV in the no relapse group was - 2.0 cm3. Median delta apparent diffusion coefficient (ADC) was lower in the relapse group versus the no relapse group (- 3.5 mm2/s vs. 71 mm2/s).

CONCLUSIONS

Early response assessment with 2-[18F]FDG-PET/MRI identified potentially predictive functional imaging biomarkers for prediction of radiotherapy outcome in CSCC, that could not be recognized with tumor measurements according to RECIST 1.1. These biomarkers (delta FTV and delta ADC) should be further evaluated. Trial registration Clinical Trials, NCT02379039. Registered 4 March 2015-Retrospectively registered, https://classic.

CLINICALTRIALS

gov/ct2/show/study/NCT02379039 .

Application of three-dimensional multi-imaging combination in brachytherapy of cervical cancer

BACKGROUND

Three-dimensional (3D) imaging has an important role in brachytherapy and the treatment of cervical cancer. The main imaging methods used in the cervical cancer brachytherapy include magnetic resonance imaging (MRI), computer tomography (CT), ultrasound (US), and positron emission tomography (PET). However, single-imaging methods have certain limitations compared to multi-imaging. The application of multi-imaging can make up for the shortcomings and provide a more suitable imaging selection for brachytherapy.

PURPOSE

This review details the situation and scope of existing multi-imaging combination methods in cervical cancer brachytherapy and provides a reference for medical institutions.

MATERIALS AND METHODS

Searched the literature related to application of three-dimensional multi-imaging combination in brachytherapy of cervical cancer in PubMed/Medline and Web of Science electronic databases. Summarized the existing combined imaging methods and the application of each method in cervical cancer brachytherapy.

CONCLUSION

The current imaging combination methods mainly include MRI/CT, US/CT, MRI/US, and MRI/PET. The combination of two imaging tools can be used for applicator implantation guidance, applicator reconstruction, target and organs at risk (OAR) contouring, dose optimization, prognosis evaluation, etc., which provides a more suitable imaging choice for brachytherapy.

Diagnostic Accuracy of 18F-FDG-PET/CT and MRI in Predicting the Tumor Response in Locally Advanced Cervical Carcinoma Treated by Chemoradiotherapy: A Meta-Analysis

Objective

The aim of this meta-analysis was to compare the diagnostic accuracy of 18F-FDG-PET/CT and MRI in predicting the tumor response in locally advanced cervical carcinoma (LACC) treated by chemoradiotherapy (CRT).

Method

This meta-analysis has been performed according to PRISMA guidelines. Systematic searches were conducted using PubMed and Embase databases for articles published from January 1, 2010, to January 1, 2020. By using the Quality Assessment of Diagnostic Accuracy Studies 2 (QUADAS-2) tool, the reviewers assessed the methodological quality scores of the selected studies. We analyzed the sensitivity, specificity, and accuracy of two diagnostic methods using Meta-DiSc 1.4 and Stata 15.

Results

An overall of 15 studies including 1132 patients were included. Sensitivities of PET/CT and MRI were 83.5% and 82.7%, while the corresponding rates for specificities were 77.8% and 68.4%, respectively. The DOR, PLR, and NLR for MRI were 15.140, 2.92, and 22.6. PET/CT had a DOR of 25.21. The PLR and NLR for PET/CT were 4.13 and 0.215, respectively. The diagnostic sensitivity and specificity of PET/CT for the detection of residual tumor were 86% and 95%, respectively. The corresponding rates for MRI were 73% and 96%, respectively. The diagnostic sensitivity and specificity of PET/CT for the detection of tumor metastases were 97% and 99%, while the corresponding rates for MRI were 31% and 98%, respectively.

Conclusion

18F-FDG PET/CT seemed to have a better overall diagnostic accuracy in the evaluation of treatment response to chemoradiotherapy in LACC patients. MRI showed a really poor sensitivity in the detection of metastases, and PET/CT performed significantly better. However, the difference between these two methods in the detection of residual disease was not significant. More studies are needed to be conducted in order to approve that 18F-FDG PET/CT can be a standard option to assess the treatment response.