Technical report on the first clinical use of a bioabsorbable PGA spacer in HDR brachytherapy for recurrent cervical cancer

In recurrent gynecologic malignancies following prior pelvic irradiation, definitive radiation therapy is often precluded by cumulative dose constraints to adjacent organs at risk (OARs), and patients may be left with only highly invasive surgical options such as total pelvic exenteration. While some institutions have explored displacement techniques such as artificial ascites or hyaluronic acid gel injection, these approaches are not widely adopted and frequently fail to ensure consistent and stable separation of OARs. We report the first clinical use of Neskeep®, a bioabsorbable polyglycolic acid (PGA) spacer, in high-dose-rate (HDR) brachytherapy for recurrent cervical cancer after prior pelvic radiation. A woman in her 40s with prior hysterectomy and HDR brachytherapy for cervical intraepithelial neoplasia grade III developed vaginal stump recurrence 4 years later. Laparoscopic placement of the PGA spacer was performed to achieve durable displacement of the small bowel, followed by eight fractions of HDR brachytherapy. Hyaluronic acid gel was also injected during each fraction to displace the bladder and rectum. The spacer maintained position and volume throughout treatment without complications. Dose-volume analysis showed a marked reduction in small bowel D₂cc (mean equivalent dose in 2 Gy fractions (EQD₂): 121.6 cGy) compared to the initial treatment (606.0 cGy), while the spacer itself received a mean D₂cc of 690.3 cGy. MRI confirmed complete response at 2 months, with no adverse events observed at that time point. The PGA spacer enabled safe, curative reirradiation in a case that would otherwise be unsuitable for further radiation therapy.