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Purpose To investigate the feasibility of a treatment planning workflow for three-dimensional image-guided cervix cancer brachytherapy, combining volumetric transrectal ultrasound (TRUS) for target definition with CT for dose optimization to organs at risk (OARs), for settings with no access to MRI. Methods and Materials A workflow for TRUS/CT-based volumetric treatment planning was developed, based on a customized system including ultrasound probe, stepper unit, and software for image volume acquisition. A full TRUS/CT-based workflow was simulated in a clinical case and compared with MR- or CT-only delineation. High-risk clinical target volume was delineated on TRUS, and OARs were delineated on CT. Manually defined tandem/ring applicator positions on TRUS and CT were used as a reference for rigid registration of the image volumes. Treatment plan optimization for TRUS target and CT organ volumes was performed and compared to MRI and CT target contours. Results TRUS/CT-based contouring, applicator reconstruction, image fusion, and treatment planning were feasible, and the full workflow could be successfully demonstrated. The TRUS/CT plan fulfilled all clinical planning aims. Dose-volume histogram evaluation of the TRUS/CT-optimized plan (high-risk clinical target volume D 90 , OARs D 2cm³ for) on different image modalities showed good agreement between dose values reported for TRUS/CT and MRI-only reference contours and large deviations for CT-only target parameters. Conclusions A TRUS/CT-based workflow for full three-dimensional image-guided cervix brachytherapy treatment planning seems feasible and may be clinically comparable to MRI-based treatment planning. Further development to solve challenges with applicator definition in the TRUS volume is required before systematic applicability of this workflow. [ABSTRACT FROM AUTHOR]

Purpose To compare the maximum high risk clinical target volume (CTV HR ) dimensions and image quality between magnetic resonance imaging (MRI), transrectal ultrasound (TRUS) and computed tomography (CT) in image guided adaptive brachytherapy (IGABT) of locally advanced cervical cancer. Material and methods All patients with locally advanced cervical cancer treated with radiochemotherapy and IGABT between 09/2012-05/2013 were included in this study. T2-weighted MRI (1.5 tesla), TRUS and CT were performed before (MRI preBT , TRUS preBT ) and/or after (MRI BT , TRUS BT and CT BT ) insertion of the applicator. 3D TRUS image acquisition was done with a customized US stepper device and software. The HR CTV was defined on 3D image sequences acquired with different imaging modalities by one blinded observer, in accordance to the GEC-ESTRO recommendations for MRI-based target volume delineation, as the complete cervical mass including the tumour, any suspicious areas of parametrial involvement and the normal cervical stroma. Maximum HR CTV width and thickness were measured on transversal planes. Image quality was classified using the following scoring system: Grade 0: not depicted, Grade 1: inability to discriminate, margin not recognizable, Grade 2: fair discrimination, margin indistinct, Grade 3: excellent discrimination, margin distinct. Descriptive statistics, mean differences between the groups, with MRI BT as reference, and a paired t -test were calculated. Results Images from 19 patients (FIGO IB: 3, IIB: 9, IIIB: 5, IVB: 2) were available for analysis. The mean difference in maximum HR CTV width of TRUS BT, TRUS preBT, MRI preBT, CT BT to MRI BT was 0.0 mm ± 4.7 (n.s.), −1.1 mm ± 5.6 (n.s.), 0.7 mm ± 6.4 (n.s.) and 13.8 mm ± 6.7 ( p < 0.001). The mean difference in maximum HR CTV thickness of TRUS BT, TRUS preBT, MRI preBT, CT BT to MRI BT was -3.4 mm ± 5.9 ( p = 0.037), −3.4 mm ± 4.2 ( p < 0.001), 2.0 mm ± 6.1 (n.s.) and 13.9 mm ± 6.3 ( p < 0.001). Mean scores of image quality of the target volume was 2.9 for TRUS preBT , 2.3 for TRUS BT , 2.9 for MRI preBT , 2.7 for MRI BT and 2.1 for CT BT . Conclusion For the assessment of the HR CTV in IGABT of cervical cancer, TRUS is within the intraobserver variability of MRI. TRUS is superior to CT as it yields systematically smaller deviations from MRI, with good to excellent image quality. Small differences of TRUS HR CTV thickness are likely related to differences in image slice orientation and compression of the cervix by the TRUS probe before insertion of the brachytherapy applicator. [ABSTRACT FROM AUTHOR]

• Local and pelvic control in FIGO 1994 stage IB were ≥95% with acceptable morbidity. • We found no isolated local relapse. Pelvic failure occurred in 3%. Most relapses were systemic. • Results of modern brachytherapy in early cervical cancer parallel those of modern surgery. Multiple treatment options are used in early local-stage cervical cancer, including combinations of surgery with neoadjuvant/adjuvant radiotherapy and chemotherapy. Our aim was to determine the outcome for definitive chemoradiation with image guided brachytherapy (IGBT). FIGO 1994 staging system was used in our study. We included 123 patients with stage IB cervical cancer, treated at 12 centers with external beam radiotherapy (EBRT) ± Chemotherapy and IGBT. Three- and 5-year actuarial local control (LC), pelvic control (PC), overall survival (OS), cancer-specific survival (CSS) and late morbidity (CTCAE v 3.0) were computed. Median age was 48 (23–82) years. FIGO 1994 stage distribution was: IB1 68% and IB2 32%; 41% of the entire cohort had nodal metastases and 73% squamous-cell carcinoma. MRI-based tumor size was >40 mm in 63%. Median EBRT dose was 45 (40–50) Gy; 84% received chemotherapy. At IGBT, mean CTV-HR D90 was 93 ± 17 Gy (EQD2 10). D2cc for bladder was 76 ± 14 Gy, rectum 66 ± 11 Gy, sigmoid 66 ± 10 Gy, bowel 67 ± 7 Gy (EQD2 3). At 43-months median follow-up, 9% of patients had systemic, 6% paraaortic, 3% pelvic-nodal and 2% local failure. Five-year LC was 98%, PC 96%, CSS 90%, OS 83%. Intestinal G3-–4 morbidity was 8%, urinary 7% and vaginal 0%. Chemoradiation with IGBT for FIGO 1994 stage IB cervical cancer leads to excellent loco-regional control with limited morbidity. In IB node-negative disease, it can be regarded equivalent to surgery in terms of oncologic outcome. In tumors with unfavorable pre-treatment characteristics, chemoradiation is the first choice to avoid combining surgery with adjuvant therapy. [ABSTRACT FROM AUTHOR]

Highlights • Nodal failure rate after chemo-radiation and MRI guided BT is 11%. • Nodal failure rates for the N− and N+ group were 7 and 16% • Complete remission after treatment was seen in 95% of N+ patients. • Nodes at diagnosis were mainly located in the pelvis, nodal failures more often in PAO. • Forty-one percent of nodal failure patients had failure outside the treated volume. Abstract Purpose/Objective(s) To investigate the patterns of nodal failure in patients enrolled in the international multicentre EMBRACE study. Materials/Methods Nodal disease at diagnosis (N−, N+) and nodal failure were analysed per region (NF) (pelvic (parametrial, common iliac, internal/external iliac), inguinal and para-aortic (PAO)) in 1338 patients. Treatment consisted of chemo-radiation and MRI guided brachytherapy. PAO radiotherapy and/or nodal boost was left to the treating centre. At time of diagnosis 52% of patients had pathologic nodes. Frequency analyses were performed in relation to patient, primary tumour and nodal disease characteristics, and treatment related factors. Results Median follow up was 34 months and 83% of NF occurred within 24 months. At diagnosis 99% of the N+ patients had pathologic nodes in the pelvis and 14% in the PAO. NF pelvic and NF PAO were reported in 55% and 68% of patients with NF, respectively. Overall NF was reported in 152 patients (11%); 7 and 16% for N- and N+ patients. Of the patients with NF, 41% were located outside the elective target (39% PAO), 40% inside and 35% inside the nodal boost target. Twelve percent of N+ patients that received a nodal boost had a NF inside the nodal boost target. Conclusion Within the EMBRACE study cohort the overall number of patients developing nodal failure is low, significantly lower for N− compared to N+ patients. Pathological nodes at diagnosis are mainly located in the pelvis, whereas nodal failures are more often reported in the PAO region. About 40% of all nodal failures were reported outside the treatment targets. [ABSTRACT FROM AUTHOR]