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BackgroundMRI sequences with short scanning times may improve accessibility of image guided adaptive brachytherapy (IGABT) of cervix cancer. We assessed the value of 3D MRI for contouring by comparing it to 2D multi-planar MRI.Patients and methodsIn 14 patients, 2D and 3D pelvic MRI were obtained at IGABT. High risk clinical target volume (HR CTV) was delineated by 2 experienced radiation oncologists, using the conventional (2D MRI-based) and test (3D MRI-based) approach. The value of 3D MRI for contouring was evaluated by using the inter-approach and inter-observer analysis of volumetric and topographic contouring uncertainties. To assess the magnitude of deviation from the conventional approach when using the test approach, the inter-approach analysis of contouring uncertainties was carried out for both observers. In addition, to assess reliability of 3D MRI for contouring, the impact of contouring approach on the magnitude of inter-observer delineation uncertainties was analysed.ResultsNo approach- or observer - specific differences in HR CTV sizes, volume overlap, or distances between contours were identified. When averaged over all delineated slices, the distances between contours in the inter-approach analysis were 2.6 (Standard deviation (SD) 0.4) mm and 2.8 (0.7) mm for observers 1 and 2, respectively. The magnitude of topographic and volumetric inter-observer contouring uncertainties, as obtained on the conventional approach, was maintained on the test approach. This variation was comparable to the inter-approach uncertainties with distances between contours of 3.1 (SD 0.8) and 3.0 (SD 0.7) mm on conventional and test approach, respectively. Variation was most pronounced at caudal HR CTV levels in both approaches and observers.Conclusions3D MRI could potentially replace multiplanar 2D MRI in cervix cancer IGABT, shortening the overall MRI scanning time and facilitating the contouring process, thus making this treatment method more widely employed.

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Since focal HER2 expression is an issue in GC, TMA construction from the paraffin-embedded surgically-obtained tissue may not reflect its real status. The aim of this study was to assess the HER2 status in tissue microarrays (TMAs) and the corresponding whole sections using HercepTest immunohistochemistry (IHC), and to correlate it and to assess the concordance of HER2 IHC and fluorescence in situ hybridization (FISH) in TMAs. Concordance of the HER2 expression status for 302 cases of gastric cancer using 9 paired TMAs was evaluated using a 2-mm core size and 305 corresponding whole sections. Concordance of the IHC and FISH HER2 status was compared. In addition,, the HER2 status was compared to clinicopathological characteristics and patients' survival. Using the whole-section approach, HER2 over-expression was found in 25.2 % (HER2 3+ 6.6 %, HER2 2+ 18.7 %) of tumours. The overall concordance of IHC between the cores and the whole section was 84.9 %; 15.1 % of the tumours showed HER2 amplification. The overall concordance of IHC and FISH on cores was 75.7 %. The level of amplification correlated with the IHC score. Relationship between the intestinal and papillary types and tumour grade was observed for tumours with over-expression and amplification, whereas tumour location was related only to over-expression. There was a statistically significant difference in the overall survival of the patients, which was related to HER2 amplification. In conclusion, good concordance of the IHC HER2 results between tissue cores in TMA and whole sections, and excellent concordance of the IHC and FISH results on tissue cores was found. At least a part of the observed IHC HER2 heterogeneity could very likely be explained by fixation artifacts. With adequate fixation, a higher concordance of IHC HER2 between the cores and the whole sections can be expected. The TMA approach could enable an easier analysis of more than one representative tumour block.