scholarly journals Hybrid TRUS/CT with optical tracking for target delineation in image-guided adaptive brachytherapy for cervical cancer

2020 ◽  
Vol 196 (11) ◽  
pp. 983-992
Author(s):  
Stéphanie Smet ◽  
Nicole Nesvacil ◽  
Johannes Knoth ◽  
Alina Sturdza ◽  
Dina Najjari-Jamal ◽  
...  

Abstract Objective To prospectively compare the interobserver variability of combined transrectal ultrasound (TRUS)/computed tomography (CT)- vs. CT only- vs. magnetic resonance imaging (MRI) only-based contouring of the high-risk clinical target volume (CTVHR) in image-guided adaptive brachytherapy (IGABT) for locally advanced cervical cancer (LACC). Methods Five patients with LACC (FIGO stages IIb–IVa) treated with radiochemotherapy and IGABT were included. CT, TRUS, and T2-weighted MRI images were performed after brachytherapy applicator insertion. 3D-TRUS image acquisition was performed with a customized ultrasound stepper device and software. Automatic applicator reconstruction using optical tracking was performed in the TRUS dataset and TRUS and CT images were fused with rigid image registration with the applicator as reference structure. The CTVHR (based on the GEC-ESTRO recommendations) was contoured by five investigators on the three modalities (CTVHR_CT, CTVHR_TRUS-CT, and CTVHR_MRI). A consensus reference CTVHR_MRI (MRIref) was defined for each patient. Descriptive statistics and overlap measures were calculated using RTslicer (SlicerRT Community and Percutaneous Surgery Laboratory, Queen’s University, Canada), comparing contours of every observer with one another and with the MRIref. Results The interobserver coefficient of variation was 0.18 ± 0.05 for CT, 0.10 ± 0.04 for TRUS-CT, and 0.07 ± 0.03 for MRI. Interobserver concordance in relation to the MRIref expressed by the generalized conformity index was 0.75 ± 0.04 for MRI, 0.51 ± 0.10 for TRUS-CT, and 0.48 ± 0.06 for CT. The mean CTVHR_CT volume of all observers was 71% larger than the MRIref volume, whereas the mean CTVHR_TRUS-CT volume was 15% larger. Conclusion Hybrid TRUS-CT as an imaging modality for contouring the CTVHR in IGABT for LACC is feasible and reproducible among multiple observers. TRUS-CT substantially reduces overestimation of the CTVHR volume of CT alone while maintaining similar interobserver variability.

2016 ◽  
Author(s):  
S. Tandon ◽  
S. Mitra ◽  
M. K. Sharma ◽  
U. Saxena ◽  
P. Ahlawat ◽  
...  

Purpose/Objective: Cervical cancer is the third most common cancer in women worldwide. Definitive chemoradiation is the accepted standard of care for patients especially for locally advanced cervical cancers. Intracavitary brachytherapy (ICBT) is an important part of definitive radiotherapy shown to improve overall survival. Interstitial brachytherapy (ISBT) is generally reserved for patients either with extensive pelvic and/or vaginal residual disease after external beam radiotherapy (EBRT) or with anatomy not allowing ICBT with standard applicators in an attempt to improve local control. We have conducted an observational study for patients who underwent image guided HDR-ISBT at our institute. Materials and Methods: Seven patients; diagnosed as a case of carcinoma cervix; were selected from the period of 2012 to 2015 who received EBRT by IMRT and for whom ICBT couldn’t be done for various reasons. These patients were then taken up for Martinez Universal Perineal Interstitial Template (MUPIT) image based ISBT. A descriptive analysis was done for doses received by HRCTV, bladder, rectum and sigmoid colon. At the end of treatment, early response at 3 months along with overall survival (OS) and disease free survival (DFS) was also calculated. Results: All the patients recruited were locally advanced with 3 patients in IIB, 1 patient in IIIA and 3 patients belonging to IIIB. The mean dose received by 95% high risk CTV (HRCTV) by IMRT was 49.75 Gy. Out of 7 patients, 3 were taken up for ISBT due to anatomical restriction whereas remaining 4 patients were included because of lack of dose coverage by ICBT. The mean doses received by 90% of HRCTV, 2 cc bladder, 2 cc rectum and 2 cc sigmoid colon were 20.58 Gy, 2.73 Gy, 3.19 Gy and 2.82 Gy respectively. The early response at 3 months was 57.14%. The DFS at one year and OS at 3 year were 53.6% and 53.3% respectively. Conclusions: Our descriptive analysis of seven patients being treated by image based ISBT have revealed that locally advanced cervical cancer patients for whom ICBT is unsuitable can achieve equitable LRC and OS with a combination of EBRT by IMRT and image based HDR-ISBT.


Brachytherapy ◽  
2017 ◽  
Vol 16 (5) ◽  
pp. 976-980 ◽  
Author(s):  
Jean Philippe Nesseler ◽  
Claire Charra-Brunaud ◽  
Julia Salleron ◽  
Jean François Py ◽  
Andres Huertas ◽  
...  

2016 ◽  
Vol 28 (5) ◽  
pp. 419-428 ◽  
Author(s):  
Pauline Castelnau-Marchand ◽  
Cyrus Chargari ◽  
Christine Haie-Meder ◽  
Renaud Mazeron

2017 ◽  
Vol 17 (1) ◽  
pp. 124-130
Author(s):  
Ekkasit Tharavichitkul ◽  
Panupat Rugpong ◽  
Nisa Chawapun ◽  
Razvan M. Galalae

AbstractPurposeThis study aims to clarify the influence of overall treatment time (OTT) on the efficiency of combined chemo-radiotherapy in cervical cancer.Material and methodsThis retrospective study enrolled 122 cervical cancer patients who had squamous cell carcinoma and had undergone definitive chemo-radiotherapy from 2009 to 2013. All patients received whole pelvic radiotherapy (WPRT) with the dose of 50 Gy in 25 fractions (with central shielding after 44 Gy) plus intracavitary brachytherapy with the dose of 28 Gy in four fractions. During WPRT, all patients received concurrent chemotherapy with weekly platinum-based regimen. The data of patient characteristics, OTT, treatment results and toxicities were collected and evaluated.ResultsThe mean follow-up time was 36 months. The mean age of patients was 52 years old; 68% of patients were stage IIB related to International Federation of Gynaecology and Obstetrics staging. Pelvic control (PC), distant metastasis-free survival (DMFS), disease-free survival (DFS) and overall survival (OS) rates did not differ significantly in the data-derived cut points of 55·8 and 53 days. No statistically significant difference in treatment results between the two groups of OTT<49 and OTT≥62 days was observed.ConclusionsIn our data-derived cut point, OTT did not influence to PC, DMFS, DFS and OS. The influence of OTT on treatment results may be found in longer periods.


2021 ◽  
pp. 20210214
Author(s):  
Hanlin Wang ◽  
Ruoxi Wang ◽  
Jiacheng Liu ◽  
Jian Zhang ◽  
Kaining Yao ◽  
...  

Objectives: To develop and evaluate a practical automatic treatment planning method for Intensity-Modulated Radiation Therapy (IMRT) in cervical cancer cases. Methods: A novel algorithm named as Optimization Objectives Tree Search Algorithm (OOTSA) was proposed to emulate the planning optimization process and achieve a progressively improving IMRT plan, based on the Eclipse Scripting Application Programming Interface (ESAPI). Thirty previously treated cervical cancer cases were selected from the clinical database and comparison was made between the OOTSA-generated plans and clinical treated plans and RapidPlan-based (RP) plans. Results: In clinical evaluation, compared with plan scores of the clinical plans and the RP plans, 22 and 26 of the OOTSA plans were considered as clinically improved in terms of plan quality, respectively. The average conformity index (CI) for the PTV in the OOTSA plans was 0.86 ± 0.01 (mean ± 1 standard deviation), better than those in the RP plans (0.83 ± 0.02) and the clinical plans (0.71 ± 0.11). Compared with the clinical plans, the mean doses of femoral head, rectum, spinal cord and right kidney in the OOTSA plans were reduced by 2.34 ± 2.87 Gy, 1.67 ± 2.10 Gy, 4.12 ± 6.44 Gy and 1.15 ± 2.67 Gy. Compared with the RP plans, the mean doses of femoral head, spinal cord, right kidney and small intestine in the OOTSA plans were reduced by 3.31 ± 1.55 Gy, 4.25 ± 3.69 Gy, 1.54 ± 2.23 Gy and 3.33 ± 1.91 Gy, respectively. In the OOTSA plans, the mean dose of bladder was slightly increased, with 2.33 ± 2.55 Gy (versus clinical plans) and 1.37 ± 1.74 Gy (versus RP plans). The average elapsed time of OOTSA and clinical planning were 59.2 ± 3.47 min and 76.53 ± 5.19 min. Conclusions: The plans created by OOTSA have been shown marginally better than the manual plans, especially in preserving OARs. In addition, the time of automatic treatment planning has shown a reduction compared to a manual planning process, and the variation of plan quality was greatly reduced. Although improvement on the algorithm is warranted, this proof-of-concept study has demonstrated that the proposed approach can be a practical solution for automatic planning. Advances in knowledge: The proposed method is novel in the emulation strategy of the physicists’ iterative operation during the planning process. Based on the existing optimizers, this method can be a simple yet effective solution for automated IMRT treatment planning.


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