Disease Control after Radiotherapy for Adult Craniopharyngioma: Clinical Outcomes from a Large Single-Institution Series

Journal of Neuro-Oncology - To report disease control and treatment-related side effects among adult patients with craniopharyngioma treated with radiotherapy. We performed a single-institution...     

Faculty opinions about a revised pre-clinical curriculum

INTRODUCTION: Medical schools having innovative curricula have been encouraged to ascertain the levels of satisfaction of faculty members with the curriculum. Faculty at schools that employ problem-based learning (PBL) have been shown to have positive perceptions, but not all schools are in a position to adopt PBL on a large scale. This study sought to determine faculty members' opinions about a new curriculum that is less ambitious than one utilizing true PBL. CONTEXT AND SETTING: Since 1997, the University of Otago Medical School (Dunedin, New Zealand) has had an integrated, modular pre-clinical curriculum that emphasizes clinical relevance. It has proved popular with students. This study focused on faculty members' impressions. METHODS: We surveyed faculty members' opinions with a questionnaire identical to one used in studies at PBL schools. Faculty compared the students and their own levels of satisfaction in the old and new curricula on 7 to 10 items. The overall response rate was 85.4% (152 of 178). RESULTS: Perceptions of the new curriculum were positive among teachers who taught during the pre-clinical years and those who taught the students only after they reached the clinical years. Results for individual questions were in the same direction and generally similar in magnitude to those reported on identical items for PBL. CONCLUSION: We conclude that a hybrid curriculum that is more acceptable to many traditional teachers and students than is PBL has almost as great a positive effect on faculty members' perceptions of students' abilities and of the curriculum as does PBL.     

Proton therapy for skull-base chondrosarcoma,a single-institution outcomes study

Background

We sought to evaluate the effectiveness of definitive or adjuvant external-beam proton therapy on local control and survival in patients with skull-base chondrosarcoma.

Methods

We reviewed the medical records of 43 patients with a median age of 49 years (range, 23–80 years) treated with double-scattered 3D conformal proton therapy for skull-base chondrosarcomas between January 2007 and February 2016. Proton therapy-related toxicities were scored using CTCAE v4.0.

Results

The median radiotherapy dose was 73.8 Gy(RBE) (range, 64.5–74.4 Gy[RBE]). Thirty-six (84%) and 7 (16%) patients underwent surgical resection or biopsy alone. Tumor grade distribution included: grade 1, 19 (44%) patients; grade 2, 22 (51%); and grade 3, 2 (5%). Forty patients had gross disease at the time of radiotherapy and 7 patients were treated for locally recurrent disease following surgery. The median follow-up was 3.7 years (range, 0.7–10.1 years). There were no acute grade 3 toxicities related to RT. At 4 years following RT, actuarial rates of overall survival, cause-specific survival, local control, and RT-related grade 3 toxicity-free survival were 95%, 100%, 89%, and 95%.

Conclusion

High-dose, double-scattered 3D conformal proton therapy alone or following surgical resection for skull-base chondrosarcoma is an effective treatment with a high rate of local control with no acute grade 3 radiation-related toxicity. Further follow-up of this cohort is necessary to better characterize long-term disease control and late toxicities.

     

Chemistry of low-valent molybdenum phosphite complexes: Models of seven-coordinate reaction intermediates

A simple synthesis of the zerovalent complex Mo[P(OCH₃)₃]₆ has been devised from a potassium reduction of MoCl₄(tetrahydrofuran)₂ followed by reaction with trimethyl phosphite at 70°. Protonation of this octahedral complex gave only low yields of the expected seven-coordinate hydride, HMo[P(OCH₃)₃]₆⁺. The major product was an octahedral nonhydridic cation, Mo[P(OCH₃)₃]₅P(OCH₃)₂⁺, derived from proton cleavage of the P—O phosphite ester bond. This octahedral cation was stereochemically nonrigid, apparently through facile methoxy group migration. Close packing by methoxy groups in this fluxional cation was established through an x-ray crystallographic study of Mo[P(OCH₃)₃]₅P(OCH₃)₂⁺-PF₆^-. Extended reaction of trifluoroactic acid with Mo[P(OCH₃)₃]₆ yielded the seven-coordinate hydride, HMo[P(OCH₃)₃]₄(O₂CCF₃), which was near pentagonal bipyramidal and was stereochemically nonrigid.