PP02  Presentation Time: 8:29 AM: Starting Interstitial, Image Guided Adaptive Brachytherapy in Botswana: Initial Experience in a High Volume, Low Resource Centre

Purpose Cervical cancer is the most common cancer treated at Gaborone Private Hospital (GPH), the only facility offering radiotherapy services in Botswana. For curative intent, patients receive concurrent chemoradiation followed by brachytherapy boost. Brachytherapy services commenced in Botswana in 2012, and treatment began by using traditional A points for planning. A successful brachytherapy project was established with mentorship by clinicians from Massachusetts General Hospital and the University of Pennsylvania. In 2021, GPH acquired a new HDR brachytherapy unit with interstitial ability. The Oncologist was sent on a brachytherapy training course (ESTRO, September 2022). We now use adaptive image guided brachytherapy with CT based planning. Initial challenges included: fear of beginning such a project, inadequate skill in whole team, inadequate time to conduct interstitial techniques and planning, lack of pre-brachytherapy imaging, and no access to general anesthesia. We report our experience in initiating adaptive HDR-brachytherapy in a resource-limited setting to assist in spreading knowledge and avert fears on performance of HDR-brachytherapy in similar settings. Materials and Methods We retrospectively reviewed the records of ten patients treated with interstitial brachytherapy in January, 2023. January was selected for analysis as it represents the highest number of interstitial applications (10/29 patients - 35%). Medical records were reviewed to evaluate clinical and demographic information of the patients, treatment methods, and EQD2. Simple proportions and doismetric data are reported. Results (Table 1) Among ten patients treated with interstitial brachytherapy, 60% were stage 3, 70% were women living with HIV. Five (50%) were treated during the last week of EBRT and 50% were treated after completion of EBRT. Only three patients had pre-brachytherapy imaging, which was CT scan. Of the remaining seven patients, brachytherapy applicator choices were made based on clinical examination. Applicators were inserted under conscious sedation, prescribed by the Oncologist. All patients had an IV line inserted and were premeditated with Paracetamol 1g IV, Oxynorm 10 mg orally, Voltaren suppository and Bromazepam 3mg orally. Applicators were inserted under sterile conditions with a free draining urinary catheter. Tandem and ovoids were generally inserted blindly, and individual wires were pushed in under CT guidance. There was no ultrasound guidance. The highest number of wires inserted was 7. Treatment was well tolerated with no significant acute toxicities. All patients attained acceptable doses to HRCTV (D90> 85Gy EQD2). OARs were within tolerance. Note prolonged treatment time to completion was attributed to Linac downtime. Conclusions In a limited resource setting without access to general anesthesia and routine CT imaging, we present a case series of interstitial brachytherapy patients with successful target dose coverage outcomes. We intent to conduct a prospective study to evaluate pain control during the procedures. Further evaluation of long term survival of these patients is warranted; however, this data is encouraging to help increase access to brachytherapy services for clinics and locations with limited access to specialty services. Training and mentorship are essential components of a successful project and it is hoped that brachytherapy training programs could be availed in Africa. Cervical cancer is the most common cancer treated at Gaborone Private Hospital (GPH), the only facility offering radiotherapy services in Botswana. For curative intent, patients receive concurrent chemoradiation followed by brachytherapy boost. Brachytherapy services commenced in Botswana in 2012, and treatment began by using traditional A points for planning. A successful brachytherapy project was established with mentorship by clinicians from Massachusetts General Hospital and the University of Pennsylvania. In 2021, GPH acquired a new HDR brachytherapy unit with interstitial ability. The Oncologist was sent on a brachytherapy training course (ESTRO, September 2022). We now use adaptive image guided brachytherapy with CT based planning. Initial challenges included: fear of beginning such a project, inadequate skill in whole team, inadequate time to conduct interstitial techniques and planning, lack of pre-brachytherapy imaging, and no access to general anesthesia. We report our experience in initiating adaptive HDR-brachytherapy in a resource-limited setting to assist in spreading knowledge and avert fears on performance of HDR-brachytherapy in similar settings. We retrospectively reviewed the records of ten patients treated with interstitial brachytherapy in January, 2023. January was selected for analysis as it represents the highest number of interstitial applications (10/29 patients - 35%). Medical records were reviewed to evaluate clinical and demographic information of the patients, treatment methods, and EQD2. Simple proportions and doismetric data are reported. (Table 1) Among ten patients treated with interstitial brachytherapy, 60% were stage 3, 70% were women living with HIV. Five (50%) were treated during the last week of EBRT and 50% were treated after completion of EBRT. Only three patients had pre-brachytherapy imaging, which was CT scan. Of the remaining seven patients, brachytherapy applicator choices were made based on clinical examination. Applicators were inserted under conscious sedation, prescribed by the Oncologist. All patients had an IV line inserted and were premeditated with Paracetamol 1g IV, Oxynorm 10 mg orally, Voltaren suppository and Bromazepam 3mg orally. Applicators were inserted under sterile conditions with a free draining urinary catheter. Tandem and ovoids were generally inserted blindly, and individual wires were pushed in under CT guidance. There was no ultrasound guidance. The highest number of wires inserted was 7. Treatment was well tolerated with no significant acute toxicities. All patients attained acceptable doses to HRCTV (D90> 85Gy EQD2). OARs were within tolerance. Note prolonged treatment time to completion was attributed to Linac downtime. In a limited resource setting without access to general anesthesia and routine CT imaging, we present a case series of interstitial brachytherapy patients with successful target dose coverage outcomes. We intent to conduct a prospective study to evaluate pain control during the procedures. Further evaluation of long term survival of these patients is warranted; however, this data is encouraging to help increase access to brachytherapy services for clinics and locations with limited access to specialty services. Training and mentorship are essential components of a successful project and it is hoped that brachytherapy training programs could be availed in Africa.