À propos de 2 cas de glandes sébacées ectopiques œsophagiennes : corrélations endoscopiques, et anatomopathologiques sur biopsies et pièces opératoires

International audienc

Ganglioneuromatosis: an unusual cause of ileal stricture mimicking Crohn's disease.

International audienceIleal idiopathic forms of ganglioneuromatosis in adults are extremely rare and represent a challenging pathologic condition for the clinician. We present two cases of ileal ganglioneuromatosis consisting of stricturing lesions that mimicked clinical and radiologic features commonly observed in Crohn's disease patients with ileal involvement

Characterization of an adaptive immune response in microsatellite-instable colorectal cancer

International audienceSporadic or hereditary colorectal cancer (CRC) with microsatellite instability (MSI) is frequently characterized by inflammatory lymphocytic infiltration and tends to be associated with a better outcome than microsatellite stable (MSS) CRC, probably reflecting a more effective immune response. We investigated inflammatory mechanisms in 48 MSI CRCs and 62 MSS CRCs by analyzing: (1) the expression of 48 cytokines using Bio-Plex multiplex cytokine assays, and (2) the in situ immune response by immunohistochemical analysis with antibodies against CD3 (T lymphocytes), CD8 (cytotoxic T lymphocytes), CD45RO (memory T lymphocytes), T-bet (Th1 CD4 cells), and FoxP3 (regulatory T cells). MSI CRC exhibited significantly higher expression of CCL5 (RANTES), CXCL8 (IL-8), CXCL9 (MIG), IL-1β, CXCL10 (IP-10), IL-16, CXCL1 (GROα), and IL-1ra, and lower expression of MIF, compared with MSS CRC. Immunohistochemistry combined with image analysis indicated that the density of CD3+, CD8+, CD45RO+, and T-bet+ T lymphocytes was higher in MSI CRC than in MSS CRC, whereas the number of regulatory T cells (FoxP3+) was not statistically different between the groups. These results indicate that MSI CRC is associated with a specific cytokine expression profile that includes CCL5, CXCL10, and CXCL9, which are involved in the T helper type 1 (Th1) response and in the recruitment of memory CD45RO+ T cells. Our findings highlight the major role of adaptive immunity in MSI CRC and provide a possible explanation for the more favorable prognosis of this CRC subtype

Regulatory T lymphocytes are associated with less aggressive histologic features in microsatellite-unstable colorectal cancers.

BACKGROUND: Colorectal cancers (CRCs) with microsatellite instability (MSI) are associated with a good prognosis and a high density of tumor-infiltrating lymphocytes (TILs). We have undertaken to determine the link between TIL densities and MSI CRC histologic features. PATIENTS AND METHODS: Using tissue microarrays, T-cell sub-population infiltration, including T cells (CD3), cytotoxic T cells (CD8) and regulatory T cells (FoxP3) were studied in 86 MSI CRCs. We separately analyzed TILs of the stromal and epithelial compartments in the tumor center, the tumoral invasion margin and associated normal tissue. RESULTS: For FoxP3+ TIL density in the tumor center stromal compartment, we found a strong negative correlation with T4 stage (p = 0.01), node invasion (p<0.001) and VELIPI (vascular emboli, lymphatic invasion and perinervous invasion) criteria (p = 0.002). CONCLUSION: The strong correlation between regulatory T cell density and the absence of VELIPI criteria suggests that this sub-group of T cells is preferentially associated with less invasive tumors

Genetic variations of the A13/A14 repeat located within the EGFR 3[prime] untranslated region have no oncogenic effect in patients with colorectal cancer.

International audienceBACKGROUND: The EGFR 3[prime] untranslated region (UTR) harbors a polyadenine repeat which is polymorphic (A13/A14) and undergoes somatic deletions in microsatellite instability (MSI) colorectal cancer (CRC). These mutations could be oncogenic in colorectal tissue since they were shown to result into increased EGFR mRNA stability in CRC cell lines. METHODS: First, we determined in a case control study including 429 CRC patients corresponding to different groups selected or not on age of tumor onset and/or familial history and/or MSI, whether or not, the germline EGFR A13/A14 polymorphism constitutes a genetic risk factor for CRC; second, we investigated the frequency of somatic mutations of this repeat in 179 CRC and their impact on EGFR expression. RESULTS: No statistically significant difference in allelic frequencies of the EGFR polyA repeat polymorphism was observed between CRC patients and controls. Somatic mutations affecting the EGFR 3[prime]UTR polyA tract were detected in 47/80 (58.8%) MSI CRC versus 0/99 microsatellite stable (MSS) tumors. Comparative analysis in 21 CRC samples of EGFR expression, between tumor and non malignant tissues, using two independent methods showed that somatic mutations of the EGFR polyA repeat did not result into an EGFR mRNA increase. CONCLUSION: Germline and somatic genetic variations occurring within the EGFR 3[prime]UTR polyA tract have no impact on CRC genetic risk and EGFR expression, respectively. Genotyping of the EGFR polyA tract has no clinical utility to identify patients with a high risk for CRC or patients who could benefit from anti-EGFR antibodies

Determination of tumor-infiltrating lymphocyte density.

<p>Examples of tumor center chips with CD3 (A), CD8 (B) and FoxP3 (C) staining. Left panels are examples of high TIL densities and right panels are examples of low TIL densities. The stroma is circled in red, the epithelium in blue, and black areas are excluded. The marked areas that are taken into account to calculate the lymphocyte infiltrate density are circled in yellow. All data were acquired with Chip’s N Cheap TMA analysis program.</p