The accuracy of Multi-detector row CT for the assessment of tumor invasion of the mesorectal fascia in primary rectal cancer

PURPOSE: To evaluate the accuracy of Multi-detector row CT (MDCT) for the prediction of tumor invasion of the mesorectal fascia (MRF). MATERIALS AND METHODS: A total of 35 patients with primary rectal cancer underwent preoperative staging magnetic resonance imaging (MRI) and MDCT. The tumor relationship to the MRF, expressed in 3 categories (1--tumor free MRF = tumor distance > or = 1 mm; 2--threatened = distance < 1 mm; 3--invasion = distance 0 mm) was determined on CT by two observers at patient level and at different anatomical locations. A third expert reader evaluated the MRF tumor relationship on MRI, which served as reference standard. Receiver operating characteristic curves (ROC-curves) and areas under these curves (AUC) were calculated. The inter-observer agreement of CT was determined by using linear weighted kappa statistics. RESULTS: The AUC of CT for MRF invasion was 0.71 for observer 1 and 0.62 for observer 2. The inter-observer agreement was kappa = 0.34. The performance of CT at mid-high rectal levels was statistically significant better compared to low anterior (obs.1: AUC = 0.88 vs. 0.50; obs 2: AUC = 0.84 vs. 0.31; P < or = 0.040). CONCLUSION: Multi-detector row CT has a poor accuracy for predicting MRF invasion in low-anterior located tumors.The accuracy of CT significantly improves for tumors in the mid-high rectum. There is a high inconsistency among readers

Humane fettgewebsständige Stammzellen zeigen interindividuell unterschiedliche adipogene Differenzierung in vitro

Einleitung: Adipose derived cells (ASC) stehen seit längerem im Fokus der Forschung. Die Nutzung ihres regenerativen Potentials rückt näher an die Grenze der klinischen Nutzung. Es fällt jedoch auf, dass die Mehrzahl der durchgeführten Studien an der etablierten 3T3-L1 Zellreihe durchgeführt wurden. Soft Tissue Augmentation unter Benutzung von Fettgewebe als organischen Filler erscheint dabei auch in der HNO attraktiv; es bleibt jedoch das Problem unvorhersehbarer Resorptionsraten des augmentierten Materials. Wir spekulieren, dass inter-individuelle Unterschiede auf ASC-Niveau einen möglichen Grund für die variierenden Resorptionsraten darstellen.Methoden: Wir untersuchten adipogenen Differenzierungsfähigkeiten verschiedener Stammzellproben, welche aus Lipoaspiraten von Patienten isoliert und einem standardisierten Differenzierungsprotokoll unterzogen wurden. Während der Differerenzierung wurden der Medienüberstand abgenommen und mittels ELISA der Adiponectingspiegel, der wichtigste Marker adipogener Differenzierung, bestimmt. Ergebnisse: Inter-individuell zeigten sich große Unterschiede sowohl im Adiponectinspiegelverlauf, als auch im Höchstwert. Auch morphologisch unterschieden sich Zellkulturen im Bezug auf Vakuolen Anzahl und Größe nach Ölrotfärbung. Schlussfolgerung: Wir schließen aus diesen Ergebnissen, dass auf Niveau der fettgewebsständigen Stammzellen, welche für den physiologischen Turnover weißen Fettgewebes und damit möglicherweise auch das Engraftment transplantierten Fettgewebes verantwortlich sind, Unterschiede existieren. Ein besseres Verständnis des Verhaltens von Nicht-Zelllinien Stammzellen könnte dazu beitragen, Weichgewebeaugmentationen bei Defekten im HNO Bereich mittels engineerten Fettgewebes in den Bereich des Denkbaren zu bringen.Der Erstautor gibt keinen Interessenkonflikt an

Fibrin gel suspended autologous chondrocytes as cell-based material for long-term injection laryngoplasty.

Objectives/Hypothesis: Injection laryngoplasty of materials for unilateral vocal-fold paralysis has shown various results regarding the long-term stability of the injected material. We evaluated a fibrin-gel based cell suspension with autologous chondrocytes in-vitro and in-vivo as long-term-stable vocal-fold augmentation material in an animal model. Study Design: This study compises an in vitro cell-culture part as well as an in vivo animal study with New Zealand White Rabbits. Methods: In in-vitro experiments, auricular chondrocytes harvested from 24 New Zealand White Rabbits cadavers were cultivated in pellet cultures to evaluate cartilage formation for 4 weeks using long-term-stable fibrin gel as carrier. Injectability and injection volume for the laryngoplasty was determined in-vitro using harvested cadaveric larynxes. In-vivo 24 Rabbits were biopsied for elastic cartilage of the ear and autologous P1 cells were injected lateral of one vocal cord into the paraglottic space suspended in a long-term-stable fibrin gel. Histologic evaluation was performed after 2, 4, 12, and 24 weeks. Results: During 12-week pellet culture, we found extracellular matrix formation and weight-stable cartilage of mature appearance. In-vivo, mature cartilage was found in two larynxes (n = 6) at 4 weeks, in four (n = 6) at 12 weeks, and in five (n = 6) at 24 weeks mostly located in the paraglottic space and sometimes with spurs into the vocalis muscle. Surrounding tissue was often infiltrated with inflammatory cells. Material tended to dislocate through the cricothyroid space into the extraglottic surrounding tissue. Conclusions: A cell-based approach with chondrocytes for permanent vocal-fold augmentation has not previously been reported. We have achieved the formation of structurally mature cartilage in the paraglottic space, but this is accompanied by difficulties with dislocated material, deformation of the augmentation, and inflammation. Level of Evidence: N/A Laryngoscope, 2020