Stereotactic body radiotherapy for medically unfit patients with cancers to the head and neck.

BACKGROUND: A single institutional experience of stereotactic body radiation therapy (SBRT) to medically unfit patients with unresectable head and neck cancers (HNCs). METHODS: A retrospective review of HNC patients undergoing SBRT was undertaken from 2011 to 2016 for fractionation ranges between 35 and 50 Gy in 4 to 6 fractions. RESULTS: One hundred and fourteen patients with 117 SBRT courses were included with mean follow-up of 10.5 months. The cohort consisted of previously untreated primary HNC (n = 48), recurrent never irradiated HNC (n = 19), oligometastatic (n = 17) non-HNC primaries and previously irradiated HNC (n = 33). Local control (LC) at 12 months and median progression free survival was 85.8%, 78.2%, 85%, 78.9% (P = .86) and 23.7, 14.8, 10.5 and 7.8 months (P = .04) respectively. Only one patient had an acute grade 4 toxicity, two patients had grade 4 late toxicities. CONCLUSIONS: HNC SBRT is an effective treatment for frail patients where longer LC is relevant but are unable to tolerate protracted radiation schedules.

Tumor radiation response enhancement by acoustical stimulation of the vasculature.

We have discovered that ultrasound-mediated microbubble vascular disruption can enhance tumor responses to radiation in vivo. We demonstrate this effect using a human PC3 prostate cancer xenograft model. Results indicate a synergistic effect in vivo with combined single treatments of ultrasound-stimulated microbubble vascular perturbation and radiation inducing an over 10-fold greater cell kill with combined treatments. We further demonstrate with experiments in vivo that induction of ceramide-related endothelial cell apoptosis, leading to vascular disruption, is a causative mechanism. In vivo experiments with ultrasound and bubbles permit radiation doses to be decreased significantly for comparable effect. We envisage this unique combined ultrasound-based vascular perturbation and radiation treatment method being used to enhance the effects of radiation in a tumor, leading to greater tumor eradication.

Volumetric changes of the anterolateral thigh free flap following adjuvant radiotherapy in total parotidectomy reconstruction.

OBJECTIVES/HYPOTHESIS: The aim of this study was to prospectively evaluate volume change in anterolateral thigh free flaps pre- and postradiotherapy and to compare computed tomography (CT) volumetric analysis with intraoperative water displacement calculation. STUDY DESIGN: Matched pair cohort study. METHODS: Thirteen patients with advanced carcinoma of the parotid gland underwent anterolateral thigh free flap reconstruction following total parotidectomy resections and neck dissection. Before the initiation of external beam radiation, routine CT planning scans were done on all patients. A minimum of 6 months after surgery, a CT scan of the head and neck was carried out, and a detailed volumetric assessment was performed. RESULTS: The mean preradiotherapy flap volume was 94.3 mL, and the postradiotherapy volume was 84.8 mL. The mean volume reduction in all 13 patients was 8.12%. CONCLUSIONS: In this prospective study we observed an 8% volume loss in anterolateral thigh free flaps 6 months postradiotherapy. This loss of volume should be taken into account when reconstructing large defects of the face and lateral skull base. Intraoperative water displacement measurement is a useful adjunctive tool for shaping free tissue transfers that are to be used for volume replacement and soft-tissue fill-in.