A retrospective, deformable registration analysis of the impact of PET-CT planning on patterns of failure in stereotactic body radiation therapy for recurrent head and neck cancer

Background: Stereotactic body radiation therapy (SBRT) has seen increasing use as a salvage strategy for selected patients with recurrent, previously-irradiated squamous cell carcinoma of the head and neck (rSCCHN). PET-CT may be advantageous for tumor delineation and evaluation of treatment failures in SBRT. We analyzed the patterns of failure following SBRT for rSCCHN and assessed the impact of PET-CT treatment planning on these patterns of failure. Methods: We retrospectively reviewed 96 patients with rSCCHN treated with SBRT. Seven patients (7%) were treated after surgical resection of rSCCHN and 89 patients (93%) were treated definitively. PET-CT treatment planning was used for 45 patients whereas non-PET-CT planning was used for 51 patients. Categories of failure were assigned by comparing recurrences on post-treatment scans to the planning target volume (PTV) from planning scans using the deformable registration function of VelocityAI™. Failures were defined: In-field (>75% inside PTV), Overlap (20-75% inside PTV), Marginal (<20% inside PTV but closest edge within 1cm of PTV), or Regional/Distant (more than 1cm from PTV). Results: Median follow-up was 7.4 months (range, 2.652 months). Of 96 patients, 47 (49%) developed post-SBRT failure. Failure distribution was: In-field12.3%, Overlap24.6%, Marginal36.8%, Regional/Distant26.3%. There was a significant improvement in overall failure-free survival (log rank p = 0.037) and combined Overlap/Marginal failure-free survival (log rank p = 0.037) for those receiving PET-CT planning vs. non-PET-CT planning in the overall cohort (n = 96). Analysis of the definitive SBRT subgroup (n = 89) increased the significance of these findings (overall failure: p = 0.008, Overlap/Marginal failure: p = 0.009). There were no significant differences in age, gender, time from prior radiation, dose, use of cetuximab with SBRT, tumor differentiation, and tumor volume between the PET-CT and non-PET-CT groups. Conclusions: Most failures after SBRT treatment for rSCCHN were near misses, i.e. Overlap/Marginal failures (61.4%), suggesting an opportunity to improve outcomes with more sensitive imaging. PET-CT treatment planning showed the lowest rate of overall and near miss failures and is beneficial for SBRT treatment planning. © 2012 Wang et al.; licensee BioMed Central Ltd

Educational Priorities for Children with Cri-Du-Chat Syndrome

There are few data on the educational needs of children with cri-du-chat syndrome: a neurodevelopmental disorder that affects learning and development. We therefore designed an Internet survey to identify parents’ educational priorities in relation to children’s level of need/ability. The survey listed 54 skills/behaviors (e.g., toileting, expresses wants and needs, and tantrums) representing 10 adaptive behavior domains (e.g., self-care, communication, and problem behavior). Parents rated their child’s current level of ability/performance with respect to each skill/behavior and indicated the extent to which training/treatment was a priority. Fifty-four surveys were completed during the 3-month data collection period. Parents identified nine high priority skills/behaviors. Results supported the view that parent priorities are often based on the child’s deficits and emergent skills, rather than on child strengths. Implications for educational practice include the need for competence to develop high priority skills/behaviors and the value of assessing children’s deficits and emergent skills to inform the content of individualized education plans