Inter-observer and intra-observer variability in reporting vaginal dose points for cervical cancer in high-dose-rate brachytherapy

Vaginal Toxicity Management in Patients with Locally Advanced Cervical Cancer following Exclusive Chemoradiation-A Nationwide Survey on Knowledge and Attitudes by the Italian Association of Radiotherapy and Clinical Oncology (AIRO) Gynecology Study Group

Background and Objective: Exclusive radiotherapy, including external beam radiotherapy (EBRT) and interventional radiotherapy/brachytherapy (IRT/BT), with concurrent cisplatin-based chemotherapy, represents the standard of care in patients with locally advanced cervical cancer (LACC). The emerging topic of vaginal toxicity has become a key endpoint in LACC management, although different approaches and non-standardized procedures were available. Our aim was to analyze a nationwide study of the attitudes of Italian gynecological radiation oncology teams in the management of LACC patients' vaginal toxicities. Methods: A nationwide survey of radiation oncologists specializing in the treatment of gynecological malignancies was performed, using the free SurveyMonkey platform, consisting of 26 items. The questionnaire was proposed by the Italian Association of Radiation Oncologists (AIRO) gynecological working group to all 183 Italian radiation oncology institutions, as per AIRO's website. Results: Fifty-eight questionnaires (31%) were completed and returned. The assessment of acute and late vaginal toxicities was systematic in 32 (55.2%) and 26 (44.8%) centers, respectively. In the case of EBRT, 70.7% of centers, according to the contouring and treatment plan data, did not contour the vagina as an organ at risk (OAR). Vaginal dose constraints were heterogeneous for both EBRT and IRT/BT. Local treatment to prevent vaginal toxicity was prescribed by 60.3% of radiation oncologists, mostly vaginal hyaluronic acid cream, and one center recommended vaginal estrogen preparations. During follow-up visits, vaginal toxicity was considered an issue to be investigated always (n = 31) or in sexually active women only (n = 11). Conclusions: This survey showed that wide variation exists with regard to recording and treating vaginal toxicity after exclusive chemoradiation for cervical cancer, underscoring the need to develop more comprehensive guidelines for contouring e-dose reporting of the vagina, so as to implement clinical approaches for vaginal toxicity.

Brachytherapy impacts on sexual function: An integrative review of the literature focusing on cervical cancer

There is growing awareness of the importance of sexual health in the quality of life of cancer patients and survivors. Brachytherapy, a vital component for the curative treatment of cervical cancer, leads to both direct and indirect sequelae that result in vaginal and sexual morbidity. The emergence of 3D image-guided adaptive brachytherapy has led to a better understanding of dose-and-effect relationships for critical organs-at-risk and there are new recommendations for vaginal dose reporting in the ongoing EMBRACE II study. An understanding of the vagina as an organ-at-risk and its dose-and-effect relationships can help brachytherapists limit dose to the vagina and improve sexual morbidity. Brachytherapists play a critical role in the primary and secondary prevention of vaginal and sexual sequelae resulting from treatment. Through close surveillance and recognition of common symptoms, brachytherapists can intervene with effective strategies to prevent and treat vaginal and sexual symptoms. This review summarizes the current literature on dosimetric factors that may predict for vaginal morbidity. It will focus on quantitative and qualitative reports of brachytherapy-related vaginal toxicity and sexual dysfunction. Lastly, it will review the available evidence supporting clinical interventions to mitigate the development and progression of vaginal and sexual sequelae to improve functional quality post-treatment.

Vaginal 11-point and volumetric dose related to late vaginal complications in patients with cervical cancer treated with external beam radiotherapy and image-guided adaptive brachytherapy

OBJECTIVE

To investigate the vaginal 11-point and volumetric dose-toxicity relationships in definitive cervical cancer radiotherapy.

METHODS

A retrospective cohort study of patients with cervical cancer with a complete response of at least 12 months was performed. Additional per vaginal examinations and patient-scoring questionnaires on the date of patient enrolment were assessed for vaginal strictures. Retrospective dosimetric analysis of vaginal 11-point and volumetric doses was performed with descriptive and probit analyses to investigate dose-toxicity relationships.

RESULTS

Ninety-seven patients were included in the study, with a 20-month median follow-up. The incidence rate of grade 3 vaginal strictures was 22.7%. A comparison between patients with grade 1-3 vaginal strictures revealed significant differences in age, stage, initial tumour size, and vaginal involvement. PIBS + 2, PIBS, PIBS-2, D + 5, and D2cc were all significantly different among grade 1-3 vaginal strictures and showed significant probit coefficients. The lateral dose points were significantly higher in grade 2 strictures, but negative probit coefficients failed to establish causal inferences. Post-estimation analyses yielded effective doses (ED) for 15% and 20% probability of grade 3 vaginal strictures (ED15 and ED20) for PIBS + 2 at 57.4 and 111 Gy₃, respectively. PIBS-2 yielded an ED20 of 7 Gy₃. D + 5 yielded positive ED10, ED15, and ED20 values of 52.2, 66.6, and 78 Gy₃, respectively.

CONCLUSIONS

This study showed a significant relationship between age, tumour size, and lower-third vaginal involvement with the incidence of vaginal toxicity. The goal of a cumulative radiotherapy dose of ≤ 55 Gy₃ to PIBS + 2, ≤5 Gy₃ to PIBS-2, and ≤ 65 Gy₃ to D + 5 points may reduce the risk of grade 3 vaginal stenosis to less than 15-20%.

The Fusion of MRI and CT in the Planning of Brachytherapy for Cancer of the Uterine Cervix

Introduction: tumors of the uterine cervix are among the most common carcinomas in women. Intracervical brachytherapy is an indispensable part of curative treatment. Although the tumor is significantly more recognizable in MRI than in CT, the practical application of MRI in brachytherapy planning is still difficult. The present study examines the technical possibilities of merging CT and MRI. Materials and Methods: the treatment files and imaging of all 53 patients who had been irradiated by image-guided adaptive brachytherapy (IGABT) between January 2019 and August 2021 at the Department of Radiotherapy of the Hannover Medical School were evaluated, retrospectively. Patients were treated first with an external beam radiotherapy (EBRT) combined with simultaneous chemotherapy. After an average of 4.2 weeks, the preparation for IGABT began. The clinical target volume (CTV) for brachytherapy was contoured first in an MRI acquired before starting EBRT (MRI 1) and once more in a second MRI just before starting IGABT (MRI 2). Then, after inserting the intravaginal applicator, a CT-scan was acquired, and the CTV was contoured in the CT. Finally, the recordings of MRI 1, MRI 2, and the CT were merged, and the congruence of CTVs was quantitatively evaluated. Results: the CTV delineated in MRI 2 was, on average, 28% smaller than that in MRI 1 after an average applied radiation dose of 42 Gy. The CTV delineated in the CT covered an average of no more than 80.8% of the CTV delineated in MRI 2. The congruence of CTVs was not superior in patients with a smit sleeve in the cervical channel, with a 3D-volumetric MRI or with a contrast-enhanced sequence for MRI. Conclusion: the anatomical shape and position of the uterus is significantly changed by introducing a vaginal applicator. Despite the superior delimitability of the tumor in MRI, brachytherapy cannot be reliably planned by the image fusion of an MRI without a vaginal applicator.