Performance and survival outcomes of defect-driven versus specimen-driven method of frozen section intraoperative margin assessment in oral cancers.

Margin status is one of the most important prognostic factors in oral cancers. Intraoperative frozen section (FS) can be performed to ensure a margin-negative resection, however the method of FS assessment is debatable. The aim of this study was to compare the defect-driven (DDA) versus specimen-driven (SDA) approach for intraoperative assessment of tumour margins in oral cancer resections and their impact on loco-regional recurrence and survival. The primary study endpoint was margin status determined from the final histopathological examination report. Secondary endpoints were disease recurrence and survival. This retrospective cohort study compared the two methods of FS in terms of their performance and survival outcomes. All oral squamous cell carcinoma patients who underwent surgery as the primary treatment from January 2018 to February 2019 were included. The involved margin rate was slightly lower with SDA than DDA (7.5% vs 11.8%), however the difference was not statistically significant. The recurrence rate was higher with DDA (19/51, 37.2%) than SDA (14/53, 26.4%), although this was not statistically significant. Local recurrence-free survival (DDA 62% vs SDA 75%; P = 0.653) and overall survival (DDA 76% vs SDA 78%; P = 0.300) at 18 months of follow-up were comparable. There was no significant difference in sensitivity or specificity of intraoperative FS for margin assessment between SDA and DDA. The type of intraoperative FS technique used did not affect loco-regional recurrence or overall survival.

Octupolar versus Néel Order in Cubic 5d

We report time-of-flight neutron spectroscopy and neutron and x-ray diffraction studies of the 5d^{2} double perovskite magnets, Ba_{2}MOsO_{6} (M=Zn,Mg,Ca). These materials host antiferromagnetically coupled 5d^{2} Os^{6+} ions decorating a face-centered cubic (fcc) lattice and are found to remain cubic down to the lowest temperatures. They all exhibit thermodynamic anomalies consistent with a single phase transition at a temperature T^{*}, and a gapped magnetic excitation spectrum with spectral weight concentrated at wave vectors typical of type-I antiferromagnetic orders. However, while muon spin resonance experiments show clear evidence for time-reversal symmetry breaking below T^{*}, we observe no corresponding magnetic Bragg scattering signal. These results are shown to be consistent with ferro-octupolar symmetry breaking below T^{*}, and are discussed in the context of other 5d double perovskite magnets and theories of exotic orders driven by multipolar interactions.

Comparison of basal lamella relaxing incision and combined conventional medialisation and controlled synechiae in functional endoscopic sinus surgery: a randomised prospective study.

OBJECTIVES: To compare combined conventional Freer medialisation and controlled synechiae, performed for middle meatal access (during the initial steps of functional endoscopic sinus surgery) and post-operative middle turbinate medialisation, with basal lamella relaxing incision, the latter of which is a single step for achieving both middle meatal access and post-operative medialisation. The study also compared the effects of controlled synechiae and basal lamella relaxing incision on post-operative olfaction. METHOD: A randomised prospective study was performed on 52 nasal cavity sides (32 patients). Only basal lamella relaxing incision was performed in one group, and both conventional medialisation and controlled synechiae were performed in the other. Intra-operative and post-operative photography was used to measure the middle meatal area. A pocket smell test was used to assess olfaction. RESULTS: There were no significant differences in operative middle meatal access and post-operative medialisation of the middle turbinate. Post-operative olfaction was affected more in the combined conventional medialisation and controlled synechiae group, compared to the basal lamella relaxing incision group, but this finding was not statistically significant. CONCLUSION: Basal lamella relaxing incision is an effective single-step technique for achieving adequate middle meatal access and post-operative medialisation, with no significant effect on olfaction.