Comparison of clinical efficacy and complications of 125I seed brachytherapy and stereotactic body radiation therapy for recurrent pulmonary metastases from colorectal carcinoma

Abstract

PurposeTo evaluate the efficacies of 125I seed implantation and stereotactic body radiation therapy (SBRT) in treatment of recurrent lung metastases from colorectal cancer, to compare the tolerance of lung tissue to both forms of radiotherapy, and to analyze the factors that affect the prognosis.Material and methodsAccording to treatment received, thirty colorectal cancer patients with post-operative lung metastases were separated into two groups: 125I seed implantation group (group A; n = 16) and SBRT group (group B; n = 14). Patients were followed up, and local control rate, survival, and post-operative complications were analyzed retrospectively. Kaplan-Meier method was used for survival analysis. Cox proportional hazards model was used to identify the independent predictors of poor prognosis.ResultsSurvival was significantly different between group A and group B (median survival, 15 months and 11.5 months, respectively; p = 0.015). Local control rates at the first, third, sixth, and twelfth months after treatment were all > 80%, with no significant difference between the two groups (p = 0.829). Significant differences were seen between the two groups in the number of treatments received (p = 0.009) and the incidence of radiation pneumonitis (p < 0.001) as well as radiation-induced pulmonary fibrosis (p = 0.005). On multivariate regression analysis radiation pneumonitis was an independent predictor of poor prognosis (HR = 3.356, 95% CI: 1.518-7.421; p = 0.003).Conclusions125I seeds brachytherapy and SBRT are both effective for control of lung metastases but the former causes milder lung tissue damage. It can be repeated after short intervals, and appears to be a safe and efficient treatment for lung metastases.

Iodine-125 seed implantation treatment of lung metastases &lt;2.5 cm using a 5-ml syringe as a guide

“…[23,24] Percutaneous ablation, either using radiofrequency or ICI, may reduce the patient treatment load and have good outcomes. [12,13,[25][26][27] Based on previous studies by our team, pulmonary metastases of 1-2 cm in size can be diagnosed and located in the lungs, and patients are able to tolerate treatment. [12,13] Nevertheless, access to small lesions (< 2.5 cm) is prone to failure, but methods for the accurate positioning of the access needle are scarce.…”

“…[12,13,[25][26][27] Based on previous studies by our team, pulmonary metastases of 1-2 cm in size can be diagnosed and located in the lungs, and patients are able to tolerate treatment. [12,13] Nevertheless, access to small lesions (< 2.5 cm) is prone to failure, but methods for the accurate positioning of the access needle are scarce. Penetrating directly through the rib into the lesion for seed implantation is contrary to the intention of minimally invasive therapy, and we do not recommend this approach.…”

“…The prescribed dose was 135 Gy, which was chosen based on our previous studies. [12,13] Local anesthesia was administered with a 5-ml syringe (2% lidocaine; Yimin, Yichang, China) at the body surface location marker (Figure 1 Figure 3E). As in our previous study, the seeds were placed 0.5-0.8 cm apart in line with the TPS to the best extent possible.…”

“…[12] Especially in the case where lung metastasis is very small, and detection and treatment occur in a timely manner, it is easy to achieve a complete response (CR). [13] Because early-detected metastases are small, the amount of seeds used is small, and radiation-induced lung injury is minimal. [13] Direct needle puncture can be challenging due to the relatively small size of the lesions and their nonstationary positioning due to lung movement during respiration.…”

“…[13] Because early-detected metastases are small, the amount of seeds used is small, and radiation-induced lung injury is minimal. [13] Direct needle puncture can be challenging due to the relatively small size of the lesions and their nonstationary positioning due to lung movement during respiration. Computed tomography (CT)-guided transthoracic needle biopsy is recommended for tissue biopsy of pulmonary lesions < 2 cm.…”