Venezia applicator with oblique needles improves clinical target volume coverage in distal parametrial tumor residue compared to parallel needles only.

PURPOSE: Residual distal parametrial involvement after radiochemotherapy is a true challenge for brachytherapists since the width and asymmetry of high-risk clinical target volume (HR-CTV) are difficult to cover properly with a standard implant. MATERIAL AND METHODS: Dosimetric plans of five patients treated with Venezia advanced gynecological applicator at our institution were reviewed. For each patient, we compared the original plan with a new plan where oblique needles were removed and re-optimized manually. Optimization process was halted when EQD210 D90 HR-CTV reached 90 Gy, when one hard constraint to organs at risk (OARs) was reached according to the EMBRACE II protocol, or when dose-rate of one of OARs exceeded 0.6 Gy/h. RESULTS: Tumors were large; median HR-CTV volume was 64 cc and median distance between tandem and outer contour of HR-CTV was 40 mm. For the five patients, HR-CTV EQD210 D90 was superior in the plan using oblique needles, with a median difference of 6.5 Gy (range, 1.7-8.5 Gy). Median D90 HR-CTV and intermediate-risk CTV (IR-CTV) were significantly increased with oblique needles: 85.9 Gy (range, 83.2-90.3 Gy) vs. 81.5 Gy (range, 77.4-84 Gy), and 68.7 Gy (range, 66.3-72.3 Gy) vs. 67 Gy (range, 64.3-69.1 Gy), p = 0.006 for both. There were no significant differences in the dose to OARs. Plans with only parallel needles had less favorable dose distribution, with cold spots on the outer parametria and higher vaginal activation to compensate parametrial coverage in its inferior part. CONCLUSIONS: VeneziaTM applicator permits reproducible application to increase CTV coverage in patients with distal parametrial tumor residue during brachytherapy, while maintaining acceptable dose to OARs.

Incorporating Magnetic Resonance Imaging (MRI) Based Radiation Therapy Response Prediction into Clinical Practice for Locally Advanced Cervical Cancer Patients.

In recent years, magnetic resonance imaging (MRI) has become one of the standard imaging tools to define the macroscopic gross tumor volume in locally advanced cervical cancer patients based on T2-weighted sequence. Recent data suggest that functional MRI could be used to potentially improve the delineation of target volumes based on physiologic features, defining radioresistant subvolumes that may require higher doses to achieve local cure. Functional imaging can be used to predict tumor biology and outcome, as well as for assessment of tumor response during radiotherapy. The concept of adaptive radiotherapy relies on the possibility of monitoring variations in target volumes structures to guide treatment-plan modification during radiotherapy, taking into account not only internal movements but also tumor response. With integrated MRI in radiotherapy linear accelerators, motion monitoring during treatment delivery has become available. MRI can be also used to accurately evaluate cervical tumor residual volume after chemoradiotherapy, and therefore allowing a personalized treatment planning for brachytherapy boost, based on tumor radiosensitivity. In this review, we discuss how MRI tumor response assessment could be included into clinical practice during radiation therapy in locally advanced cervical cancer patients.

Hypnosedation for endocavitary uterovaginal applications: A pilot study.

PURPOSE: Implantations for uterovaginal brachytherapy are usually performed under general or spinal anesthesia, which are not without risk. As it is a rather short procedure and since postoperative pain is minimal, hypnosedation was proposed to selected patients requiring endocavitary applications as part of their routine treatment. METHODS AND MATERIALS: Consecutive patients requiring intracavitary uterovaginal brachytherapy from January to October 2019 were included if they accepted the procedure. A premedication was systematically administered. Hypnosedation was based on an Ericksonian technique. The procedure was immediately interrupted if the patient requested it, in cases of extreme anxiety or pain. Procedure was in that case rescheduled with a "classical" anesthesia technique. RESULTS: A total of 20 patients were included. Four patients had to be converted toward a general anesthesia: one because of a fibroma on the probe's way and three young patients with a very anteverted/retroverted uterus that was painful at every mobilization. Mean and maximum pain scores during implant were 2.9/10 and 5.1/10, respectively. The most painful maneuver was cervical dilation for 45% of the patients, followed by mold insertion in 40% of cases. About 85% of the patients declared that hypnosis helped them relax; 90% of the patients would recommend the technique. No procedure-related complication occurred. CONCLUSION: With a 70% success rate (correct implant with mean pain and anxiety scores < 5), one can conclude that uterovaginal brachytherapy implantation under hypnosedation is feasible and received a high satisfaction rate from the patients. This technique may reduce overall treatment time in a context of difficult access to the OR and to anesthesiologists, while reducing anesthetic drugs resort and postoperative nausea.