RESUMEN
Purpose: To compare the pre-plan and post-plan dosimetric parameter differences of 3D-printed non-coplanar templates (3D-PNCT)-assisted computed tomography (CT)-guided iodine-125 (125I) radioactive seed implantation brachytherapy (RISI) in patients with inguinal lymph node metastasis (ILNM). Material and methods: This was a retrospective study of 15 patients with ILNM carcinomas treated with 3D-PNCT-assisted CT-guided RISI between May, 2015 and April, 2018. All patients underwent prior external beam radiotherapy (EBRT) or surgery. Dosimetric parameters included D90, D100 (dose delivered to 90% and 100% of the volume, respectively), V100, V150, V200 (percentage of target volume receiving 100%, 150%, and 200% of the prescribed dose, respectively). Quality parameters included conformal index (CI), external index (EI), and homogeneity index (HI). Paired t-test and Bland-Altman analysis were applied to compared pre-plan and post-plan parameters. Results: The median gross tumor volume (GTV) in the pre-plan was 8.7 ml (range, 0.8-185.1 ml). There were statistically significant differences in V100, V150, CI, and EI (p < 0.05). Bland-Altman analysis indicated that accidental error of RISI was small. In 1 of the 15 cases, D90 and D100 exceeded the prescribed therapeutic accuracy. In 1 of the 15 cases, V150, EI, and GTV were outside the specified accuracy range (95% confidence interval). Conclusions: 3D-PNCT-assisted CT-guided RISI is a safe, accurate, and feasible choice in ILNM treatment. The procedure of RISI has significantly improved. The pre-plan can be accurately executed by 3D-PNCT-assisted CT-guided RISI.
RESUMEN
The recurrence rate of cervical cancer after primary treatment can reach 60%, and a poor prognosis is reported in most cases. Treatment options for the recurrence of cervical cancer mainly depend on the prior treatment regimen and the location of recurrent lesions. Re-irradiation is still considered as a clinical challenge, owing to a high incidence of toxicity, especially in in-field recurrence within a short period of time. Recent advances in radiotherapy have preliminarily revealed encouraging outcomes of re-irradiation. Several centers have concentrasted on stereotactic body radiation therapy (SBRT) for the treatment of well-selected cases. Meanwhile, as the image-guiding techniques become more precise, a better dose profile can also be achieved in brachytherapy, including high-dose-rate interstitial brachytherapy (HDR-ISBT) and permanent radioactive seed implantation (PRSI). These treatment modalities have shown promising efficacy with a tolerable toxicity, providing further treatment options for recurrent cervical cancer. However, it is highly unlikely to draw a definite conclusion from all of those studies due to the large heterogeneity among them and the lack of large-scale prospective studies. This study mainly reviews and summarizes the progress of re-irradiation for recurrent cervical cancer in recent years, in order to provide potential treatment regimens for the management of re-irradiation.
