Free propagation phase-contrast breast CT provides higher image quality than cone-beam breast-CT at low radiation doses: a feasibility study on human mastectomies

In this study we demonstrate the first direct comparison between synchrotron x-ray propagation-based CT (PB-CT) and cone-beam breast-CT (CB-CT) on human mastectomy specimens (N = 12) including different benign and malignant lesions. The image quality and diagnostic power of the obtained data sets were compared and judged by two independent expert radiologists. Two cases are presented in detail in this paper including a comparison with the corresponding histological evaluation. Results indicate that with PB-CT it is possible to increase the level of contrast-to-noise ratio (CNR) keeping the same level of dose used for the CB-CT or achieve the same level of CNR reached by CB-CT at a lower level of dose. In other words, PB-CT can achieve a higher diagnostic potential compared to the commercial breast-CT system while also delivering a considerably lower mean glandular dose. Therefore, we believe that PB-CT technique, if translated to a clinical setting, could have a significant impact in improving breast cancer diagnosis.

The lymphangiogenesis inhibitor esVEGFR-2 in human embryos: expression in sympatho-adrenal tissues and differentiation-induced up-regulation in neuroblastoma

Tumour-induced hem- and lymph-angiogenesis are frequently associated with tumour progression. Vascular endothelial growth factor-C (VEGF-C) is a potent inducer of lymphangiogenesis, while the endogenous soluble splice-variant of VEGF receptor-2, esVEGFR-2, acts as a natural inhibitor. Previously we have shown down-regulation of esVEGFR-2 mRNA in progressed stages of neuro-blastoma (NB), a tumour derived from sympatho-adrenal precursor cells. Here we studied the immunolocalization of esVEGFR-2 in human embryos, infantile adrenal gland and primary NB. We also quantified esVEGFR-2 mRNA in NB cell lines after differentiation-induction by all-trans retinoic acid (ATRA). By immunoperoxidase staining we observed expression of esVEGFR-2 in both the sympathetic trunk and the adrenal medulla. Additionally, esVEGFR-2 was found in spinal ganglia, floor plate of the neural tube, choroid plexus, notochord, arterial endothelium, skeletal muscle, epidermis and gut epithelium. Developing and circulating leukocytes showed the strongest signal. In NB, esVEGFR-2 was considerably stronger in differentiating low grade tumours with neuronal phenotype than in undifferentiated lesions. Differentiation-induction of the NB cell line SMS-Kan with 5-10 µM ATRA resulted in a significant increase of esVEGFR-2 mRNA after 6, 9 and 12 days. We show that esVEGFR-2 is widely expressed in embryonic tissues. Especially, the adrenal medulla and circulating leukocytes seem to be potent inhibitors of lymphangiogenesis. We provide additional evidence for a role of esVEGFR-2 in NB. Thereby, high levels of esVEGFR-2 correlate with a more differentiated phenotype, and may inhibit tumour progression by inhibition of lymphangiogenesis.

Histomorphological tumor regression grading of esophageal carcinoma after neoadjuvant radiochemotherapy: which score to use?

Histopathological tumor regression grade (TRG) has been shown to be a prognostic factor in patients with esophageal cancer after neoadjuvant radiochemotherapy (RCT). The system introduced by Mandard to group TRG (Cancer 1994;73:2680-2686) has been used to analyse and discuss its prognostic significance on survival in a single institution retrospective analysis: TRG 1 (complete regression) - TRG 5 (absence of regressive changes). Sixty patients with locally advanced (T3/4 or N1) adenocarcinoma or squamous cell carcinoma received cisplatin-based RCT. Three to four weeks later operation for curative intent was performed. Median follow-up was 17.7 months. Histopathological tumor stages were stage 0 in 17%, stage I in 10%, stage II in 60%, stage III in 12% and stage IVA in 1%. The 5-year overall survival (OS) rate was 35%. In univariate analysis, ypN-status and TRG correlated significantly with OS (P = 0.004, P = 0.0008, respectively). While OS of TRG 1 differed significantly from all other groups, no differences in OS between the other TRG groups were seen. Patients with complete tumor regression after neoadjuvant RCT showed a much better survival than patients with tumors that responded less to induction therapy. Further qualitative subdivision of tumor regression could not identify patient groups with significant differences in prognosis. After comparing our data with the literature, it is reasonable to consider classifying all patients into 'Complete tumor regression' and 'Incomplete tumor regression'.