Updated Trends in Cervical Cancer Brachytherapy Utilization and Disparities in the United States From 2004 to 2020

Anticoagulation management in gynecologic brachytherapy patients with perioperative or chronic thromboembolic disease: A retrospective analysis

PURPOSE

Women on chronic anticoagulation (AC) who require operative brachytherapy for gynecologic malignancies represent a clinical challenge, but no guidelines exist regarding patient selection for brachytherapy or their perioperative management. We aimed to understand the incidence of hemorrhagic and embolic events in our patients on chronic AC and suggest management strategies for this patient population.

MATERIALS AND METHODS

A retrospective, single institutional study of patients treated with operative, gynecologic brachytherapy from 2013 to 2023 was performed to identify patients on chronic AC. We determined indications for AC use, oncologic therapy characteristics, duration of AC interruption, and therapy outcomes. The primary aim was to determine perioperative embolic or hemorrhagic complications as measured by the Common Terminology Criteria for Adverse Events.

RESULTS

Of 304 patients treated with operative implants, 32 (10%) were on chronic AC for venous thromboembolism (n = 25), or atrial fibrillation/flutter (n = 13). The most common malignancies were cervical (n = 15) and inoperable uterine (n = 11). Implants were intracavitary (n = 14), interstitial (n = 6), or hybrid (n = 12) with a median (range) of 2 (1-3) implants, 4 (2-5) fractions, and 2 (1-3) days of bedrest per implant. 63% (n = 20) had an epidural for analgesia. AC was held for a median 3 days in 94% (n = 30) prior to the operative implant, and pharmacologic DVT prophylaxis was used in 78% (n = 25). There were two grade ≥ 2 hemorrhagic events and no new embolic events.

CONCLUSIONS

The rate of bleeding and embolic events was acceptable, and women on chronic AC should not be excluded from potentially lifesaving operative brachytherapy, including complex cases that require spinal analgesia and interstitial applicators.

Trends in brachytherapy in utilization for vaginal cancer in the United States from 2004 to 2021

PURPOSE

Brachytherapy (BT) is recommended for vaginal cancer treatment, particularly cases of bulky and/or recurrent disease. However, previous studies noted a decline in utilization rates. This study examines recent trends in BT utilization to assess for reversal in trends.

MATERIAL AND METHODS

This study analyzed the National Cancer Database (NCDB) of patients with FIGO stage I to IVA vaginal cancer treated between 2004 and 2021. A log binomial regression with robust variance was used to estimate incidence rate ratios (IRRs) of BT utilization over time and identify potential factors associated with receipt.

RESULTS

Brachytherapy use increased from 48.0 % in 2004 to 63.3 % in 2021. Factors associated with increased brachytherapy use included, receiving care at an academic/research program (IRR: 1.35 95 % CI: 1.18-1.55), integrated cancer program (1.22 [1.06-1.41]), and diagnosis after 2018 (1.31 [1.21-1.42]). Factors associated with decreased use included American Indian or Alaskan Native race (0.55 [0.31-0.97]) when compared to white race, age over 70 (≥ 70-79 years: 0.91 [0.83-0.99]; ≥ 80 years: 0.68 [0.61-0.76]) when compared to age less than 50, and stage II (0.91 [0.86-0.96]), III (0.71 [0.67-0.75]), or IVA (0.43 [0.37-0.50]) disease when compared to stage I. Finally, geographic differences were also observed in BT use.

CONCLUSIONS

In patients with stage I - IVA vaginal cancer from 2004 to 2021, brachytherapy utilization has significantly increased. These results indicate a recent start of the reversal of previously identified declining use of brachytherapy. However, more work is needed to ensure equitable use across demographic strata.

National Cancer Database analysis of radiation therapy consolidation modality and dose for inoperable endometrial cancer

OBJECTIVE

We utilized the National Cancer Database (NCDB) to evaluate trends and assess outcomes in radiation therapy (RT) boost modality and total dose among medically inoperable endometrial cancer (EC) patients with locoregional disease.

METHODS

Patients with International Federation of Gynecology and Obstetrics (FIGO) stage I - IIIC2 inoperable EC treated with RT ± chemotherapy were analyzed. Practice patterns compared external beam RT (EBRT) versus high-dose-rate brachytherapy (BT) boost and total RT dose (palliative: ≤3000 cGy, definitive low dose [DLD]: 4500 - 6249 cGy, definitive high dose [DHD]: ≥6250 cGy) over time. Kaplan-Meier method evaluated overall survival (OS) and Cox proportional hazard modeling assessed variables associated with OS.

RESULTS

NCDB included 1755 total cases, of which 1209 received a radiotherapy boost. From 2004 to 2019, boost modality rates differed with increasing utilization of BT consolidation and a decreasing rate of palliation. Predictors of a palliative dose were stage III disease, Black race, N2 disease, and poorly or undifferentiated grade. Multivariable analysis found BT boost was associated with lower mortality compared to EBRT (HR: 0.81, CI: 0.68-0.97; p = 0.019). Mortality rates were higher for palliation versus DHD. Additional factors associated with inferior survival were increasing age, worse Charlson-Deyo score, higher T stage, higher N stage, and moderately, poorly, or undifferentiated grade.

CONCLUSIONS

Utilization of BT boost for locoregionally confined, medically inoperable EC has increased since 2004. Brachytherapy consolidation remains an effective RT modality for medically inoperable EC, associated with lower mortality compared to EBRT consolidation.

Generalizability of deep learning in organ-at-risk segmentation: A transfer learning study in cervical brachytherapy

PURPOSE

Deep learning can automate delineation in radiation therapy, reducing time and variability. Yet, its efficacy varies across different institutions, scanners, or settings, emphasizing the need for adaptable and robust models in clinical environments. Our study demonstrates the effectiveness of the transfer learning (TL) approach in enhancing the generalizability of deep learning models for auto-segmentation of organs-at-risk (OARs) in cervical brachytherapy.

METHODS

A pre-trained model was developed using 120 scans with ring and tandem applicator on a 3T magnetic resonance (MR) scanner (RT3). Four OARs were segmented and evaluated. Segmentation performance was evaluated by Volumetric Dice Similarity Coefficient (vDSC), 95 % Hausdorff Distance (HD95), surface DSC, and Added Path Length (APL). The model was fine-tuned on three out-of-distribution target groups. Pre- and post-TL outcomes, and influence of number of fine-tuning scans, were compared. A model trained with one group (Single) and a model trained with all four groups (Mixed) were evaluated on both seen and unseen data distributions.

RESULTS

TL enhanced segmentation accuracy across target groups, matching the pre-trained model's performance. The first five fine-tuning scans led to the most noticeable improvements, with performance plateauing with more data. TL outperformed training-from-scratch given the same training data. The Mixed model performed similarly to the Single model on RT3 scans but demonstrated superior performance on unseen data.

CONCLUSIONS

TL can improve a model's generalizability for OAR segmentation in MR-guided cervical brachytherapy, requiring less fine-tuning data and reduced training time. These results provide a foundation for developing adaptable models to accommodate clinical settings.

A survey on brachytherapy training of gynecological cancer focusing on the competence of residents in China

BACKGROUND

The brachytherapy is an indispensable treatment for gynecological tumors, but the quality and efficiency of brachytherapy training for residents is still unclear.

METHODS

An anonymous questionnaire was designed to collect information on gynecological brachytherapy (GBT) training for radiation oncology residents from 28 training bases in China. The questionnaire content was designed based on the principle of competency based medical education (CBME). The Likert scale was employed to evaluate self-reported competence and comprehension regarding GBT. A total of 132 senior residents were included in the final analysis.

RESULTS

53.79% (71/132) of senior residents had experience in performing image-guided GBT, whereas 76.52% (101/132) had observed the procedure during their standardized residency training. The proportion of senior residents who reported having the self-reported competence to independently complete the GBT was 78.03% for intracavity GBT, 75.00% for vaginal stump GBT, and 50.03% for interstitial GBT, respectively. The number of successful completion of Interstitial, intracavity and vaginal GBT was correlated with the self- confidence of trainees after standardized training. In particular, the independent completion of interstitial GBT for more than 20 cases was an independent factor for the self-reported competence of senior residents. During the training period, 50.76% and 56.82% of the residents had not participated in the specialized examinations and professional GBT courses.

CONCLUSIONS

The study revealed that the self-confidence of residents to independently complete brachytherapy was relatively high, and the specialized curriculum setting and training process assessment for brachytherapy training still need to be strengthened in the future.

Updated Trends in the Utilization of Brachytherapy in Cervical Cancer in the United States: A Surveillance, Epidemiology, and End-Results Study

PURPOSE

Our previous Surveillance, Epidemiology, and End Results (SEER) study revealed a concerning decline in brachytherapy utilization in the United States between 1988 and 2009. This study evaluates recent trends in brachytherapy utilization in cervical cancer and identifies factors and survival benefit associated with the use of brachytherapy treatment.

METHODS AND MATERIALS

Using SEER data, 8500 patients with International Federation of Gynecologists and Obstetricians 2009 stage IB2-IVA cervical cancer treated with external beam radiation therapy (EBRT) between 2000 and 2020 were identified. Logistic regression analysis was performed on potential factors associated with brachytherapy use: age, marital status, race, ethnicity, income, metropolitan status, year of diagnosis, SEER region, histology, grade, and stage. To adjust for differences between patients who received brachytherapy and those who did not, propensity-score matching was used. Multivariable Cox regression analysis assessed the association of brachytherapy use with cervical cancer-specific mortality (CSM) and all-cause mortality (ACM) in the matched cohort.

RESULTS

Sixty-four percent of the 8500 women received brachytherapy in combination with EBRT; 36% received EBRT alone. The brachytherapy utilization rate declined sharply in 2003/2004 (lowest rate 44% in 2003) and then gradually improved especially in 2018 to 2020 (76%). Factors associated with higher odds of brachytherapy use included younger age, married (vs single), later years of diagnosis, certain SEER regions, and earlier stage. In the propensity-score matched cohort, brachytherapy treatment was associated with lower 4-year cumulative incidence of cancer death (32.1% vs 43.4%; P < .001) and better overall survival (64.0% vs 51.4%; P < .001). Brachytherapy treatment was independently associated with lower CSM (hazard ratio, 0.70; 95% CI, 0.64-0.76; P < .001) and ACM (hazard ratio, 0.72; 95% CI, 0.67-0.78; P < .001).

CONCLUSIONS

Brachytherapy utilization among SEER regions has improved since 2004 in patients with stage IB2-IVA cervical cancer. Brachytherapy use remains independently associated with significantly lower CSM and ACM and is an essential component of treatment for patients with locally advanced cervical cancer.

Review of brachytherapy clinical trials: a cross-sectional analysis of ClinicalTrials.gov

INTRODUCTION

Characterizing the landscape of clinical trials including brachytherapy can provide an overview of the current status and research trends which may guide further areas of investigation.

METHOD

We queried 449,849 clinical trials from the ClinicalTrials.gov registry using brachytherapy-related keywords from 1980 to 2023, yielding 245 multi-arm and 201 single-arm, brachytherapy trials. Multi-arm and single-arm brachytherapy trials were compared using 12 trial protocol elements.

RESULTS

The number of trials including brachytherapy has increased over time, with over 60% of trials registered in 2010 onwards. The majority of clinical trials were Phase 2 or 3, evaluated both safety and efficacy, and were funded by academic sponsors. The most common tumor sites evaluated in brachytherapy clinical trials include prostate, cervix, liver, endometrium, and breast.

CONCLUSION

There remains continued interest in clinical trials including brachytherapy focused on evaluation of novel delivery systems, treatment planning, and new indications. More brachytherapy clinical trials are needed to define the optimal clinical utilization and advance prospective research in this field.