Xiang Zhang

A novel multi‐channel applicator with a U‐shaped channel for vaginal intracavity brachytherapy

AbstractBackgroundEndometrial cancer is one of the most common gynecological malignancies in the world. Vaginal brachytherapy is an important postoperative adjuvant treatment for endometrial cancer. However, a common problem with existing applicators is insufficient dose at the vaginal apex.PurposeThis study describes the Hangzhou (HZ) cylinder, a novel 3D printed vaginal intracavity brachytherapy applicator, detailing its characteristics, dose distribution, and clinical applications.Methods and MaterialsThe HZ cylinder is distinguished by its unique structure: a U‐shaped channel with a 2 mm diameter, a straight central axis channel of the same diameter, and 10 parallel straight channels. For comparison, standard plans were employed, designed to ensure that a minimum of 95% of the prescribed dose reached 5 mm beneath the mucosal surface. We conducted comparative analyses of mucosal surface doses and doses at a 5 mm depth below the mucosa between the HZ cylinder and a conventional single‐channel cylinder across various treatment schemes. Additionally, the study examined dose differences in target volume and organs at risk (OARs) between actual HZ cylinder plans and hypothetical single‐channel plans.ResultsIn the standard plans, mucosal surface doses at the apex of the vagina were 209.32% and 200.61% of the prescribed dose with the HZ and single‐channel cylinders, respectively. The doses on the left and right wall mucosal surfaces varied from 149.26% to 178.13% and 142.98% to 180.75% of the prescribed dose, and on the anterior and posterior wall mucosal surfaces varied from 128.87% to 138.50% and 142.98% to 180.75% of the prescribed dose. Analysis of 24 actual treatment plans revealed that when the vaginal tissue volume dose covering 98% (vaginal D98%) was comparable between the HZ cylinder and virtual single‐channel plans (6.74 ± 0.07 Gy vs. 6.69 ± 0.10 Gy, p = 0.24), rectum doses of HZ cylinder plans were significantly lower than those of single‐channel plans (D1cc, 5.96 ± 0.56 Gy vs. 6.26 ± 0.71 Gy, p = 0.02 and D2cc, 5.26 ± 0.52 Gy vs. 5.56 ± 0.62 Gy, p = 0.02).ConclusionsThe HZ cylinder demonstrates a reduction in dose to the rectum and bladder while maintaining adequate target volume coverage. Its mucosal surface dose is comparable to that of the traditional single‐channel cylinder. These findings suggest that the HZ cylinder is a viable and potentially safer alternative for vaginal brachytherapy, warranting further investigation with larger sample sizes.

Intratumoral injection of oncolytic virus (H101) in combination with concurrent chemoradiotherapy for locally advanced cervical cancer

To evaluate the efficacy of primary tumor bulk reduction and the safety of concurrent chemoradiotherapy in combination with H101, a type of oncolytic virus, for the treatment of locally advanced cervical cancer. Patients diagnosed with stage IIB or III cervical cancer according to the International Federation of Gynecology and Obstetrics (FIGO 2009), with tumor length ≥6 cm, were enrolled at Zhejiang Cancer Hospital from July 2015 to April 2017. All patients received concurrent chemoradiotherapy in combination with intratumoral H101 injection before and during external beam radiotherapy. Outcomes included progression free survival, overall survival, tumor regression after external beam radiotherapy, and side effects. A total of 23 patients were included in the safety analysis and, of these, 20 were included in the efficacy analysis. Median follow-up time was 38 (range 10-58) months. The 3 year local, regional, and overall progression free survival rates for the 20 patients were 95%, 95%, and 65%, respectively, and the 3 year overall survival rate was 74.3%. Median tumor length was reduced from 6.6 cm (range 6-7.3) before treatment to 4.1 cm (range 2.2-5.5) after external beam radiotherapy. Median tumor volume was reduced from 88.4 cm H101 injection may enhance primary tumor regression for locally advanced cervical cancer, with an acceptable safety profile. This treatment regimen should undergo further prospective randomized controlled studies.ChiCTR-OPC-15006142.

HPV Vaccine, Imiquimod, and Metformin Combination Trial

The goal of this clinical trial is to explore whether additional treatments can help strengthen the participant's immune system to fight cancer caused by the Human Papillomavirus (HPV), a virus spread through intimate skin-to-skin contact. The trial will also monitor the safety of these treatments. The main questions it aims to answer are: Does the combination of treatments help the participant's body fight the cancer more effectively when used alongside standard therapy? What side effects or medical issues arise when using these experimental treatments? Researchers will use three experimental therapies along with the participant's standard treatment to find out if these therapies work better together than standard treatment alone. Participants will: Receive HPV vaccinations during the 2nd and 4th week of radiation, and again at weeks 8, 10, 12, and 16 after completing radiation. Have blood samples taken, tumor cells brushed from the surface, and imiquimod cream applied during each visit. Take a daily metformin pill and apply an imiquimod suppository three times a week for two weeks after each visit.