Morphologic, morphometrical and histochemical proprieties of the costal cartilage in children with pectus excavatum.

Pectus excavatum (PE) is the most frequent anterior chest deformity occurring in approximately one of 1000 live births. Despite the excellent achievements in the treatment of the disease, the etiology of PE is yet to be clarified. It is believed that the cause for PE is an intrinsic costal cartilage abnormality leading to an overgrowth of the cartilage, which pushes the sternum backward. Several histological studies revealed contradictory results and failed to identify a clear structural abnormality of the costal cartilage responsible for the apparition of PE. In this article, we focused on identifying the microscopic disturbances of the costal cartilage in patients with PE. We obtained cartilage samples from 29 children with PE and 18 control cartilage samples. The samples were subjected to morphologic, morphometrical and histochemical assess. The results indicate a young, immature pattern of the cartilage matrix with a normal cell/matrix ratio. These results sustain the theory that the cause of PE is to be found inside the costal cartilage and the most plausible cause is a global overgrowth of the costal cartilage.

Simultaneous demonstration of mast cells and blood vessels by the combined method CD34--alcian blue-safranin in lip tumors.

The aim of the study was to evaluate the mast cell-blood vessel relationship using double staining CD34/AAS. Sections from 14 cases with lip tumors have been stained with Hematoxylin-Eosin. On additional sections from each case, we highlighted blood vessels by immunohistochemistry for CD34 antigen using the method LSAB2-HRP/DAB, followed by alcian blue-safranin stain for mast cells. We quantified the density, distribution and the mast cell types as well as the correlation with the number of blood vessels. All cases have been positive for both staining. We observed a significant correlation between the number of vessels and the mast cells (p = 0.003). In one case, we observed the mast cells stained with safranin (red), the vascular density being less than the mast cells density. Our results confirmed the data from the literature with respect to the large number of mast cells observed in the malignant tumors. The increased vascular density together with the mast cell density suggests a correlation between these two elements in the tumor angiogenesis, possibly though the VEGF secretion. The CD34/AAS stain is a quick and simple method and it allows an optimal correlation between the number of mast cells and blood vessels on the same section. The type of mast cells correlated with microvessel density is a powerful argument towards the involvement of the mast cells in the tumor angiogenesis of the malignances of the lips.

Lymphatic vessels identified with podoplanin. Comparison of immunostaining with three different detection systems.

The aim of the study was to find the optimal immunostaining protocol for monoclonal mouse anti human podoplanin antibody clone 18H5, which is less studied. We tested three detection systems for different antibody dilutions and antigen retrieval methods applied on normal and tumor breast tissues, lip squamous cell carcinoma, kidney tumors and testis carcinoma. The interpretation was linked to the background staining, specificity for the lymphatic endothelium and cross-reactivity. The ABC method gave a high background even the antibody dilution was increased. No immunostaining was obtained with Envision detection system for any dilution or type of antigen retrieval. We obtained the best results using LSAB+ working system for an antibody dilution of 1:500 with no background and podoplanin expression was restricted to the lymphatic endothelium. We consider that the standardization of immunostaining protocol is the first step for an optimal interpretation of the podoplanin expression using less studied antibody clones.