Low-activity 125I implantation into VX2 tumor rabbits and quantitative evaluation of the precise therapeutic effect

There is still controversy about quantitatively evaluating the therapeutic effect of radioactive low-activity iodine-125 seeds (¹²⁵I seeds). In the present study, a paired VX₂ tumor model in a rabbit hind leg muscle was established, which is virus-induced anaplastic squamous cell carcinoma characterized by hypervascularity, rapid growth and easy propagation in the skeletal muscle. ¹²⁵I seeds with 0.4 and 0.7 mCi activity were implanted into the left and right legs, respectively, using a radiation treatment planning system under positron emission tomography (PET)/computed tomography (CT) guidance. PET/CT scans and hematoxylin and eosin staining were observed at 72 h and 2 and 4 weeks after implantation to assess the therapeutic effect. The results showed that the average tumor length and standard uptake value (SUV) decreased over time, and both ¹²⁵I seed groups achieved therapeutic effects at 4 weeks post-implantation. Quantitative evaluation of tumor inhibition rate, SUV variation and tumor marker ratio (Bcl-2/Bax) suggested that 0.7 mCi ¹²⁵I seeds were more suitable than 0.4 mCi seeds in a clinical setting.

Therapeutic effects and prognostic factors of 125I brachytherapy for pelvic recurrence after early cervical cancer surgery

To investigate the efficacy of ¹²⁵I seed implantation in the treatment regimen of pelvic recurrence after early cervical cancer surgery and to analyse prognostic factors. To evaluate efficacy and analyse prognostic factors of ¹²⁵I seed implantation for pelvic recurrence after early cervical cancer surgery. A prospective study was conducted on 62 patients who experienced pelvic recurrence after early cervical cancer surgery between August 2005 and September 2015. The 62 patients were treated and assessed in 2 groups (n = 30). All 62 patients were randomized into two groups that received two different treatment regimens: the treatment group (n = 30), which received ¹²⁵I particle implantation therapy, and the control group (n = 32), which received whole-pelvic irradiation using the anteroposterior/posteroanterior field and cisplatin-based concurrent chemoradiation therapy. The efficacy/efficiency of ¹²⁵I seed implantation and prognostic factors were analysed by logistic regression. Overall survival was determined by Kaplan-Meier analysis. Multivariate analysis results were obtained by the Cox proportional hazards regression model. The effective control rates at 1, 3, 6 and 12 months were 76.7%, 80.0%, 83.3%, and 86.7% in the ¹²⁵I particle implantation group. The total effective control rates at 1, 3, 6 and 12 months were 65.6%, 65.5%, 62.5%, and 71.9% in the chemoradiotherapy group. Significant differences were observed between the two groups. The overall survival rates at 1, 2, 3, 4, and 5 years and the median overall were 96.7%, 93.3%, 86.7%, 71.9%, 65.6% and 4.34 years, respectively, in the ¹²⁵I seed implantation group and 81.3%, 71.9%, 62.5%, 56.3%, 53.1% and 3.59 years, respectively, in the control group. There were statistically significant differences in survival rates depending on the diameter of the largest recurrent pelvic tumour (χ² = 6.611, P = 0.010). The multivariate analysis showed that the survival rates were related to the diameter of the largest recurrent pelvic tumour (χ² = 4.538, P = 0.033). ¹²⁵I implantation is an effective, safe, and promising method for the treatment of pelvic recurrence after early cervical cancer surgery. The diameter of the recurrent pelvic tumour was identified as a significant independent prognostic factor in patients who received ¹²⁵I implantation.

Recombined humanized endostatin (Endostar) intravenous infusion in the treatment of refractory nasopharyngeal carcinoma: Three case reports

RATIONALE

Refractory nasopharyngeal carcinoma is challenging to treat and at present there is no standard treatment or any good choice.

PATIENT CONCERNS

Although the three patients in our case reports had already underwent multiple treatments before, they still suffered from disease recurrence of nasopharyngeal carcinoma.

DIAGNOSIS

They were diagnosed as refractory nasopharyngeal carcinoma.

INTERVENTIONS

A continuous infusion of Endostar, an antiangiogenic agent, combined with chemotherapy and radiation therapy was given to treat the patients.

OUTCOMES

Patients showed complete or partial response to the combined therapy as evidenced by regression of tumors and decrease in plasma Epstein-Barr virus (EBV) DNA load.

LESSONS

Continuous infusions of Endostar in combination with chemotherapy and/or radiation therapy showed promising efficacy and safety. The combination therapy indicates a new approach to treat refractory nasopharyngeal carcinoma.

Feasibility and Clinical Value of CT-guided (125)I Brachytherapy for Bilateral Lung Recurrences from Colorectal Carcinoma

PURPOSE

To prospectively evaluate the feasibility and clinical value of computed tomography (CT)-guided iodine 125 ((125)I) brachytherapy to treat bilateral lung recurrences from colorectal carcinoma.

MATERIALS AND METHODS

This study was approved by Sun Yat-sen University Cancer Center Institutional Review Board and all patients provided informed written consent. Seventy-two patients with bilateral lung recurrences from colorectal carcinoma were enrolled and randomly divided into two groups. Thirty-three were percutaneously treated with CT-guided (125)I brachytherapy (group A) and the other 39 were only given symptomatic and supportive treatments (group B). Follow-up contrast agent-enhanced CT scans were reviewed and efficacy of treatment was evaluated. (125)I brachytherapy was considered a success if it achieved the computerized treatment planning system criteria 1 month after procedure. Analyses included Kaplan-Meier, Mantel-Cox log-rank test, and Cox proportional hazards regression.

RESULTS

In group A, 37 (125)I brachytherapy procedures were performed in 33 patients with 126 lung metastatic lesions and the success rate was 87.9% (29 of 33 patients). The local control rate of 3, 6, 12, 24, and 36 months was 75.8%, 51.5%, 33.3%, 24.2%, and 9.1%, respectively. A small amount of pulmonary hematoma occurred in five patients, and six patients presented with pneumothorax with pulmonary compression of 30%-40%. No massive bleeding or radiation pneumonitis occurred. The mean overall survival (OS) of group A was significantly longer than that of group B, and (125)I brachytherapy was an independent factor that affected the OS (group A, 18.8 months; group B, 8.6 months; hazard ratio, 0.391 [95% confidence interval: 0.196, 0.779]; P = .008).

CONCLUSION

CT-guided (125)I brachytherapy is feasible and safe for the treatment of bilateral lung recurrences from colorectal carcinoma.

In vivo molecular imaging and radionuclide (131I) therapy of human nasopharyngeal carcinoma cells transfected with a lentivirus expressing sodium iodide symporter

INTRODUCTION

Despite recent improvements in the survival rates for nasopharyngeal carcinoma (NPC), novel treatment strategies are required to improve distant metastasis-free survival. The sodium iodine symporter (NIS) gene has been applied for in vivo imaging and cancer therapy. In this study, we examined the potential of NIS gene therapy as a therapeutic approach in NPC by performing non-invasive imaging using 125I and 131I therapy in vivo.

METHODS

We constructed a lentiviral vector expressing NIS and enhanced green fluorescent protein (EGFP) under the control of the human elongation factor-1α (EF1α) promoter, and stably transfected the vector into CNE-2Z NPC cells to create CNE-2Z-NIS cells. CNE-2Z and CNE-2Z-NIS tumor xenografts were established in nude mice; 125I uptake, accumulation and efflux were measured using micro-SPECT/CT imaging; the therapeutic effects of treatment with 131I were assessed over 25 days by measuring tumor volume and immunohistochemical staining of the excised tumors.

RESULTS

qPCR, immunofluorescence and Western blotting confirmed that CNE-2Z-NIS cells expressed high levels of NIS mRNA and protein. CNE-2Z-NIS cells and xenografts took up and accumulated significantly more 125I than CNE-2Z cells and xenografts. In vitro, 131I significantly reduced the clonogenic survival of CNE-2Z-NIS cells. In vivo, 131I effectively inhibited the growth of CNE-2Z-NIS xenografts. At the end of 131I therapy, CNE-2Z-NIS xenograft tumor cells expressed higher levels of NIS and caspase-3 and lower levels of Ki-67.

CONCLUSION

Lentiviruses effectively delivered and mediated long-lasting expression of NIS in CNE-2Z cells which enabled uptake and accumulation of radioisotopes and provided a significant therapeutic effect in an in vivo model of NPC. NIS-mediated radioiodine treatment merits further investigation as a potentially effective, low toxicity therapeutic strategy for NPC.