Efficacy observation of interstitial brachytherapy in locally recurrent and metastatic advanced gynecologic cancer / 肿瘤研究与临床

ABSTRACT

Objective:To evaluate the efficacy and safety of interstitial brachytherapy for locally recurrent and metastatic advanced gynecologic tumors.Methods:The data of patients with local recurrence and metastasis of advanced gynecological tumors who underwent brachytherapy in Shanxi Province Cancer Hospital from June 2020 to July 2021 were retrospectively analyzed. Objective remission rate (ORR) was compared among patients grouped according to the size, location of the lesion, and progression-free survival (PFS) before recurrence. Kaplan-Meier method was used to analyze the PFS after recurrence and group comparison was performed by using log-rank (Mantal-Cox) test. Multivariate Cox proportional hazard model was used to analyze the influencing factors of PFS after recurrence. The acute and advanced radiation injuries were also summarized.Results:A total of 20 patients were enrolled and the whole ORR was 80% (16/20). Subgroup analysis showed that 13 patients with focal length < 4 cm had objective remission, and 3 patients with focal length ≥ 4 cm had objective remission; the difference in ORR between the two groups was statistically significant ( P = 0.007). And 3 cases out of 6 cases with PFS time less than 6 months before recurrence and 13 cases out of 14 cases with PFS time equal to or more than 6 months before recurrence all had objective remission, and the difference was statistically significant ( P = 0.061). The median follow-up time was 6 months (1-13 months). By the end of follow-up, 9 patients (45%) had disease progression. Univariate survival analysis showed that patients with focal length < 4 cm (≥ 4 cm vs. < 4 cm HR = 4.192, 95% CI 0.992-17.710, P = 0.029), PFS time before recurrence ≥ 6 months (≥ 6 months vs. < 6 months HR = 0.163, 95% CI 0.038-0.696, P = 0.004), and radiation dose ≥ 15 Gy (≥ 15 Gy vs. < 15 Gy HR = 0.207, 95% CI 0.049-0.881, P = 0.016) had better PFS after recurrence, but multivariate Cox regression analysis showed that the above factors were not independent factors of PFS after recurrence (all P > 0.05). None of 20 patients had radiation injury of rectum and bladder above grade 3. Conclusion:The therapeutic effect of interstitial brachytherapy for local recurrence and metastasis of advanced gynecological tumors is clear and safe.