Colorectal mucosa is targeted by toxic agents, which can initiate or promote colon cancer. The mechanism of damage might be a focal irritation with loss of normal epithelial cell barrier function. Genetic alterations in tumors may also affect host inflammatory response. The aim of this study was to define the extent of inflammation in colorectal mucosa, along colorectal carcinogenesis, and in microsatellite stable and unstable colorectal carcinomas. We collected 103 samples of normal colorectal mucosa from 65 patients (35 with colorectal cancer or adenoma, 8 with inflammatory bowel diseases, and 22 controls with normal colonoscopy). We also examined 24 aberrant crypt foci, 14 hyperplastic polyps, 16 adenomas, and 67 samples of colorectal carcinoma. Immunohistochemistry was used to count myeloperoxidase (MPO)-positive cells (neutrophils and monocytes) in Â100

In recent years, preoperative therapy has become standard procedure for locally advanced rectal cancer. Tumor shrinkage due to preoperative chemotherapy-radiation therapy (CRT) is now a reality, and pathologically complete responses are not uncommon. Some researchers are now addressing organ preservation, thus increasing the demand for both functional and morphologic radiologic evaluation of response to CRT to distinguish responding from nonresponding tumors. On magnetic resonance (MR) images, post-CRT tumor morphologic features and volume changes have a high positive predictive value but a low negative predictive value for assessing response. Preliminary results indicate that diffusion-weighted MR imaging, especially at high b values, would be effective for prediction of treatment outcome and for early detection of tumor response. Some authors have reported that the use of apparent diffusion coefficient values in combination with other MR imaging criteria significantly improves discrimination between malignant and benign lymph nodes. Sequential determination of fluorodeoxyglucose uptake at positron emission tomography/computed tomography has proved useful in differentiating responding from nonresponding tumors during and at the end of CRT. However, radionuclide techniques have limitations, such as low spatial resolution and high cost. Large studies will be needed to verify the most effective morphologic and functional imaging modalities for post-CRT restaging of rectal cancer. Supplemental material available at http://radiographics.rsna.org/lookup/suppl/doi:10.1148/rg.303095085/-/DC1.

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Background Neuroblastoma (NB) is a paediatric tumour of the sympathetic nervous system. Half of all cases are defined high-risk with an overall survival less than 40% at 5 years from diagnosis. The lack of in vitro models able to recapitulate the intrinsic heterogeneity of primary NB tumours has hindered progress in understanding disease pathogenesis and therapy response. Methods Here we describe the establishment of 6 patient-derived organoids (PDOs) from cells of NB tumour biopsies capable of self-organising in a structure resembling the tissue of origin. Results PDOs recapitulate the histological architecture typical of the NB tumour. Moreover, PDOs expressed NB specific markers such as neural cell adhesion molecules, NB84 antigen, synaptophysin (SYP), chromogranin A (CHGA) and neural cell adhesion molecule NCAM (CD56). Analyses of whole genome genotyping array revealed that PDOs maintained patient-specific chromosomal aberrations such as MYCN amplification, deletion of 1p and gain of chromosome 17q. Furthermore, the PDOs showed stemness features and retained cellular heterogeneity reflecting the high heterogeneity of NB tumours. Conclusions We were able to create a novel preclinical model for NB exhibiting self-renewal property and allowing to obtain a reservoir of NB patients’ biological material useful for the study of NB molecular pathogenesis and to test drugs for personalised treatments.

Hereditary spherocytosis (HS) and sickle cell disease (SCD) are associated with splenomegaly and spleen dysfunction in pediatric patients. Scant data exist on possible correlations between spleen morphology and function in HS and SCD. This study aimed to assess the histologic and morphometric features of HS and SCD spleens, to get possible correlations with disease pathophysiology. In a large series of spleens from SCD, HS, and control patients, the following parameters were considered: (i) macroscopic features, (ii) lymphoid follicle (LF) density, (iii) presence of perifollicular marginal zones, (iv) presence of Gamna-Gandy bodies, (v) density of CD8-positive sinusoids, (vi) density of CD34-positive microvessels, (vii) presence/distribution of fibrosis and smooth muscle actin (SMA)-positive myoid cells, and (viii) density of CD68-positive macrophages. SCD and HS spleens had similar macroscopic features. SCD spleens had lower LF density and fewer marginal zones than did HS spleens and controls. SCD also showed lower CD8-positive sinusoid density, increased CD34-positive microvessel density and SMA-positive myoid cells, and higher prevalence of fibrosis and Gamna-Gandy bodies. HS had lower LF and CD8-positive sinusoid density than did controls. No significant differences were noted in red pulp macrophages. By multivariate analysis, most HS spleens clustered with controls, whereas SCD grouped separately. A multiparametric score could predict the degree of spleen changes irrespective of the underlying disease. In conclusion, SCD spleens display greater histologic effacement than HS, and SCD-related changes suggest impaired function due to vascular damage. These observations may contribute to guide the clinical management of patients.