Sunday, June 19, 20229:00 AM - 10:00 AMGSOR1 Presentation Time: 9:00 AM: Feasibility of Hybrid Intracavitary-Interstitial Brachytherapy for Cervical Cancer with Minimal Sedation

Abstract

<h3>Purpose</h3> Pain control techniques during high-dose rate hybrid intracavitary-interstitial brachytherapy (HBT) for cervical cancer vary widely per institutional preference, with many centers opting for general anesthesia (GA) or conscious sedation (CS) to facilitate each fraction. The incorporation of GA tends to increase treatment duration and intra-fraction patient shifting, which can compromise treatment reproducibility and efficacy. Furthermore, patients undergoing brachytherapy for cervical cancer typically require up to five fractions, with each round of GA capable of causing adverse long-term sequelae. The safety of using intravenous sedatives for CS as alternatives to GA for HBT procedures has been recently demonstrated, but concerns remain over sedative-related side effects. Here we describe the single-institutional results of a series of patients treated with HBT and ASA-defined minimal sedation utilizing oral analgesic and anxiolytic medications instead of GA or CS. <h3>Materials and Methods</h3> The charts of patients who underwent HBT treatments for cervical cancer from June 2018 to May 2020 were retrospectively reviewed. Prior to HBT, all patients underwent EUA and Smit sleeve placement under general anesthesia or deep sedation. The decision to use interstitial needles was made either based on the EUA or if there was a perceived dosimetric advantage during the patient's intracavitary brachytherapy. Oral lorazepam and oxycodone/acetaminophen were taken between 30-90 minutes before the procedure for minimal sedation. HBT placement was performed on the computed tomography (CT) table with needle advancement under CT-guidance. After confirmation of satisfactory apparatus placement via CT imaging, patients were transferred to the treatment bed and relocated to the brachytherapy suite for connection to the afterloader and treatment. <h3>Results</h3> Treatments with minimal sedation were attempted in 63 patients. A total of 244 interstitial implants with 453 needles were placed via CT-guidance. The analgesic doses were: 10 oxycodone and 650 acetaminophen - 77.9% (190/244), 5 mg oxycodone and 325 mg acetaminophen - 7.4% (18/244), 5 mg morphine - 3.7% (9/244), 4 mg morphine - 1.2% (3/244), 2 mg morphine - 1.2% (3/244), 15 mg oxycodone - 2% (5/244), and no analgesic medication - 6.7% (16/244). The anxiolytic doses were 2.0 mg lorazepam - 8.6% (21/244), 1.0 mg lorazepam - 41.8% (102/244), 0.5 mg lorazepam - 44.7% (109/244) and no anxiolytic medication - 4.9% (12/244). See Table 1 for further details. Sixty-one patients (96.8%, 61/63) tolerated the procedure without any additional intervention, while two patients (3.2%, 2/63) required use of epidural anesthesia to complete their treatments. None of the patients in the series required a transition to general anesthesia for the procedure. <h3>Conclusions</h3> In our series, the treatment of HBT for cervical cancer with minimal sedation was feasible at a high percentage (96.8%). The ability to perform HBT without GA or CS could reduce anesthesia-related adverse effects and be more efficient, cost-effective, and better-tolerated. In addition, using minimal sedation may enable more widespread use of HBT, which could lead to improved brachytherapy dosimetry and outcomes. Further investigations using this technique are warranted to assess for effects on patient-reported quality of life, patient treatment satisfaction, treatment duration and completion rates, dosimetric coverage, and tumor control.