Hypofractionated Pelvic Radiation Therapy Followed by Complex Brachytherapy Results in Adequate Disease Control and Limited Toxicity in Women with Uterine and Cervical Carcinoma

Purpose: Radiation therapy is an integral treatment modality in the management of patients with gynecological cancers, and recent advances with IMRT and brachytherapy have paved the way for highly conformal plans thus reducing recurrence rates and patient morbidity and mortality secondary to adverse events. Conventional pelvic irradiation may often be inappropriate in patients with locally advanced disease or even in patient with curable stage if deemed to be high risk given their medical comorbidities, or in elderly patients with physical or mental impairment. Thus, a shorter and hypofractionated course of pelvic radiation followed by brachytherapy might be more suitable in this patient population. We aim to evaluate the efficacy and tolerability of a short course hypofractionated pelvic radiotherapy followed by complex brachytherapy in women with uterine and cervical carcinoma.

Methodology: A total of twelve patients treated with hypofractionated pelvic radiotherapy and complex brachytherapy between September 2019 and March 2023 received a variable dose of 30 to 42 Gy in 10 to 15 fractions of external beam radiotherapy (EBRT) followed by 21 to 36 Gy in 3 to 6 fractions of brachytherapy. All patients received EBRT through IMRT technique, and brachytherapy was delivered by means of a tandem-based applicator (n = 7), Syed (n = 1), Y-applicator (n = 1), or multichannel vaginal cylinder (n = 3).

Results: The mean EQD2 to the GTV was 88.90 Gy, and that to the organs at risk was limited to 58.76 Gy to the bladder, 52.81 Gy to the rectum, 55.18 Gy to the sigmoid, 56.43 Gy to the small bowel, and D50% of 17.91 Gy to the pelvic bones. Radiotherapy was well tolerated and there were no reported grade 4 or 5 toxicities. At 2 years, a total of 5 patients recurred, two locally, two distally, and one locally and distally, for a 2-year LRR rate of 33% and DM rate of 35%. At the time of analysis, four patients had died, two of whom from disease recurrence, making the 2-year PFS and OS rates 40% and 76%, respectively.

Conclusions: The results of this retrospective single institution analysis conducted at UPMC suggests that hypofractionated IMRT followed by complex brachytherapy for the management of primary uterine or cervical cancers is well tolerated at short-term follow-up and resulted in satisfactory disease control and survival, therefore warranting the initiation of a prospective phase 1/2 nonrandomized controlled trial to adequately evaluate this treatment paradigm.

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