Microsatellite instability (MSI) due to mismatch repair deficiency (dMMR) is common in colorectal cancer (CRC). These cancers are associated with somatic coding events, but the noncoding pathophysiological impact of this genomic instability is yet poorly understood. Here, we perform an analysis of coding and noncoding MSI events at the different steps of colorectal tumorigenesis using whole exome sequencing and search for associated splicing events via RNA sequencing at the bulk-tumor and single-cell levels. Our results demonstrate that MSI leads to hundreds of noncoding DNA mutations, notably at polypyrimidine U2AF RNA-binding sites which are endowed with cis-activity in splicing, while higher frequency of exon skipping events are observed in the mRNAs of MSI compared to non-MSI CRC. At the DNA level, these noncoding MSI mutations occur very early prior to cell transformation in the dMMR colonic crypt, accounting for only a fraction of the exon skipping in MSI CRC. At the RNA level, the aberrant exon skipping signature is likely to impair colonic cell differentiation in MSI CRC affecting the expression of alternative exons encoding protein isoforms governing cell fate, while also targeting constitutive exons, making dMMR cells immunogenic in early stage before the onset of coding mutations. This signature is characterized by its similarity to the oncogenic U2AF1-S34F splicing mutation observed in several other non-MSI cancer. Overall, these findings provide evidence that a very early RNA splicing signature partly driven by MSI impairs cell differentiation and promotes MSI CRC initiation, far before coding mutations which accumulate later during MSI tumorigenesis.

In France, about 2000 new cases of anal cancer are diagnosed annually. Squamous cell carcinoma is the most common histological type, mostly occurring secondary to persistent HPV16 infection. Invasive cancer is preceded by precancerous lesions. In addition to patients with a personal history of precancerous lesions and anal cancer, three groups are at very high risk of anal cancer: (i) men who have sex with men and are living with HIV, (ii) women with a history of high-grade squamous intraepithelial lesions (HSILs) or vulvar HPV cancer, and (iii) women who received a solid organ transplant more than 10 years ago. The purpose of screening is to detect HSILs so that they can be treated, thereby reducing the risk of progression to cancer. All patients with symptoms should undergo a proctological examination including standard anoscopy. For asymptomatic patients at risk, an initial HPV16 test makes it possible to target patients at risk of HSILs likely to progress to cancer. Anal cytology is a sensitive test for HSIL detection. Its sensitivity is greater than 80% and exceeds that of proctological examination with standard anoscopy. It is indicated in the event of a positive HPV16 test. In the presence of cytological abnormalities and/or lesions and a suspicion of dysplasia on clinical examination, high-resolution anoscopy is indicated. Performance is superior to that of proctological examination with standard anoscopy. However, this technique is not widely available, which limits its use. If high-resolution anoscopy is not possible, screening by a standard proctological examination is an alternative. There is a need to develop high-resolution anoscopy and triage tests and to evaluate screening strategies.

PDF file - 83K, Baseline characteristics of 52 patients with RCC lung metastasis. * determined by Heng et al.

PDF file - 56K, P values corresponding to different cutoff (minimum P value, first, second and third quartile) in CRC and RCC lung metastases. {section sign}P values were corrected by the formula proposed by Altman et al.

Background: Mismatch repair-deficient (dMMR) tumors displaying microsatellite instability (MSI) represent a paradigm for the success of immune checkpoint inhibitor (ICI)-based immunotherapy, particularly in patients with metastatic colorectal cancer (mCRC). However, a proportion of patients with dMMR/MSI mCRC exhibit resistance to ICI. Identification of tools predicting MSI mCRC patient response to ICI is required for the design of future strategies further improving this therapy.Patients and methods: We combined high-throughput DNA and RNA sequencing of tumors from 116 patients with MSI mCRC treated with anti-programmed cell death protein 1 & PLUSMN; anti-cytotoxic T-lymphocyte-associated protein 4 of the NIPICOL phase II trial (C1, NCT03350126, discovery set) and the ImmunoMSI prospective cohort (C2, validation set). The DNA/RNA predictors whose status was significantly associated with ICI status of response in C1 were subsequently validated in C2. Primary endpoint was progression-free survival by immune RECIST (iRECIST) (iPFS).Results: Analyses showed no impact of previously suggested DNA/RNA indicators of resistance to ICI, e.g. MSIsensor score, tumor mutational burden, or specific cellular and molecular tumoral contingents. By contrast, iPFS under ICI was shown in C1 and C2 to depend both on a multiplex MSI signature involving the mutations of 19 microsatellites hazard ratio cohort C2 (HRC2) = 3.63; 95% confidence interval (CI) 1.65-7.99; P = 1.4 x 10e3] and the expression of a set of 182 RNA markers with a non-epithelial transforming growth factor beta (TGFB)-related desmoplastic orientation (HRC2 = 1.75; 95% CI 1.03-2.98; P = 0.035). Both DNA and RNA signatures were independently predictive of iPFS.Conclusions: iPFS in patients with MSI mCRC can be predicted by simply analyzing the mutational status of DNA microsatellite-containing genes in epithelial tumor cells together with non-epithelial TGFB-related desmoplastic RNA markers.

Supplementary Figures S1-S2; Supplementary Table S1.

PDF file - 101K, Influence of pre-operative patient treatments on the distribution of CD8+, DC-LAMP+ and NKp46+ immune cells in CRC (a, b and c) and RCC lung metastases (d, e and f). 63/140 patients with CRC lung metastases have been treated with neo-adjuvant chemotherapy and 9/52 patients with RCC lung metastases have been treated with IL2/IFN. Whiskers length represents 10-90 percentile. ns, not significant (Mann-Whitney test).

La survenue d’un adénocarcinome et d’un lymphome coliques synchrones est un évènement extrêmement rare. Nous rapportons ici, la sixième observation dans la littérature d’un lymphome à cellules B de la zone marginale, diagnostiqué fortuitement chez un patient de 77 ans opéré pour adénocarcinome de l’angle colique droit. Cette observation illustre l’importance de ne pas méconnaitre cette association, qui bien que rare, mais pose cependant aux thérapeutes un dilemme pour sa prise en charge.Synchronous presentation of a colonic adenocarcinoma and lymphoma is extremely rare. We describe here, the sixth observation of a marginal zone B-cell lymphoma, which was incidentally diagnosed in a 77-year-old patient, who was operated for adenocarcinoma of hepatic flexure. This case shows the importance to be aware of this rare association and highlights the dilemma of its management.

PDF file - 107K, Kaplan-Meier curves for the duration of OS according to the presence of CD8+ T cells in the center of the tumor (CT) (a), in the invasive margin (IM) (b) and in combined regions (CT+IM) (c) of CRC lung metastases. Statistical comparison was performed by the log-rank test.

PDF file - 148K, Kaplan-Meier curves for the duration of OS according to the presence of CD8+ T cells in the center of the tumor (CT) (a), in the invasive margin (IM) (b) and in combined regions (CT+IM) (c) of RCC lung metastases. Representation of the Kaplan-Meier curves for the duration of OS according to the presence of NKp46+ cells in the CT (d), in the IM (e) and in combined region (CT+IM) (f) of RCC lung metastases. Statistical comparison was performed by the log-rank test.

PDF file - 90K, Baseline characteristics of 140 patients with CRC lung metastasis. The stage was determined by pathological examination at the time of diagnosis.

Abstract Purpose: If immune cells are involved in tumor surveillance and have a prognostic impact in most primary tumors, little is known about their significance in metastases. Because patients' survival is heterogeneous, even at metastatic stages, we hypothesized that immune cells may be involved in the control of metastases. We therefore characterized the tumor immune microenvironment and its prognostic value in colorectal and renal cell carcinoma (RCC) metastases, and compared it to primary tumors. Experimental Design: We analyzed by immunohistochemistry (n = 192) and qPCR (n = 32) the immune environments of colorectal carcinoma and RCC lung metastases. Results: Metastases from colorectal carcinoma and RCC have different immune infiltrates. Higher densities of DC-LAMP+ mature dendritic cells (P < 0.0001) and lower densities of NKp46+ NK cells (P < 0.0001) were observed in colorectal carcinoma as compared to RCC metastases, whereas densities of T cells were similar. High densities of CD8+ and DC-LAMP+ cells correlated with longer overall survival (OS) in colorectal carcinoma (P = 0.008) and shorter OS in RCC (P < 0.0001). High NK-cell densities were associated with improved survival in RCC (P = 0.002) but not in colorectal carcinoma. Densities of immune cells correlated significantly from primary to relapsing metastases for the same patient. A TH1 orientation was found in colorectal carcinoma metastases, whereas a heterogeneous immune gene expression was found in RCC metastases. Conclusions: Our results show a major prognostic value of the immune pattern (CD8+/DC-LAMP+ cell densities) in colorectal carcinoma and RCC, reproducible from primary to metastatic tumors, although with opposite clinical impacts, and highlight the role of the tumor cell in shaping its immune environment. Clin Cancer Res; 19(15); 4079–91. ©2013 AACR.

OBJECTIVE:The aim of this study to describe a new international dataset for pathology reporting of colorectal cancer surgical specimens, produced under the auspices of the International Collaboration on Cancer Reporting (ICCR).BACKGROUND:Quality of pathology reporting and mutual understanding between colorectal surgeon, pathologist and oncologist are vital to patient management. Some pathology parameters are prone to variable interpretation, resulting in differing positions adopted by existing national datasets.METHODS:The ICCR, a global alliance of major pathology institutions with links to international cancer organizations, has developed and ratified a rigorous and efficient process for the development of evidence-based, structured datasets for pathology reporting of common cancers. Here we describe the production of a dataset for colorectal cancer resection specimens by a multidisciplinary panel of internationally recognized experts.RESULTS:The agreed dataset comprises eighteen core (essential) and seven non-core (recommended) elements identified from a review of current evidence. Areas of contention are addressed, some highly relevant to surgical practice, with the aim of standardizing multidisciplinary discussion. The summation of all core elements is considered to be the minimum reporting standard for individual cases. Commentary is provided, explaining each element's clinical relevance, definitions to be applied where appropriate for the agreed list of value options and the rationale for considering the element as core or non-core.CONCLUSIONS:This first internationally agreed dataset for colorectal cancer pathology reporting promotes standardization of pathology reporting and enhanced clinicopathological communication. Widespread adoption will facilitate international comparisons, multinational clinical trials and help to improve the management of colorectal cancer globally.

The dysplasia grading of Barrett’s esophagus (BE), based on the histomorphological assessment of formalin-fixed, paraffin-embedded (FFPE) tissue, suffers from high interobserver variability leading to an unsatisfactory prediction of cancer risk. Thus, pre-analytic preservation of biological molecules, which could improve risk prediction in BE enabling molecular and genetic analysis, is needed. We aimed to evaluate such a molecular pre-analytic fixation tool, PAXgene-fixed paraffin-embedded (PFPE) biopsies, and their suitability for histomorphological BE diagnostics in comparison to FFPE. In a ring trial, 9 GI pathologists evaluated 116 digital BE slides of non-dysplastic BE (NDBE), low-grade dysplasia (LGD), high-grade dysplasia (HGD), and esophageal adenocarcinomas (EAC) using virtual microscopy. Overall quality, cytological and histomorphological parameters, dysplasia criteria, and diagnosis were analyzed. PFPE showed better preservation of nuclear details as chromatin and nucleoli, whereas overall quality and histomorphologic parameters as visibility of basal lamina, goblet cells, and presence of artifacts were scored as equal to FFPE. The interobserver reproducibility with regard to the diagnosis was best for NDBE and EAC ( κ F = 0.72–0.75) and poor for LGD and HGD ( κ F = 0.13–0.3) in both. In conclusion, our data suggest that PFPE allows equally confident histomorphological diagnosis of BE and EAC, introducing a novel tool for molecular analysis and parallel histomorphological evaluation.

Glomus tumors (GTs) are perivascular tumors mostly occurring in the distal extremities. Rare cases arise in the digestive tract and may be misdiagnosed with neuroendocrine or gastrointestinal stromal tumors. We aimed to specify the features of GT of the upper digestive tract. Clinical, histological, phenotypic, and molecular features of 16 digestive GTs were analyzed, of whom two underwent whole exome and RNA sequencing to search for gene alterations. RNA-sequencing disclosed a t(1:5)(p13;q32) translocation, which resulted in the fusion of CARMN and NOTCH2 in two GTs. The fusion gene encoded a protein sequence corresponding to the NOTCH2 intracellular domain that functions as transcription factor. These finding was supported by high expression of genes targeted by NOTCH. The CARMN-NOTCH2 translocation was detected in 14 out of 16 (88%) GTs of the upper digestive tract; but in only in two out of six cutaneous GTs (33%). Most digestive GT arose from the stomach (n = 13), and the others from duodenal (2) or oesophagous (1). Nuclear expression of NOTCH2 was detected in the 14 cases containing the fusion transcripts. The CARMN-NOTCH2 fusion transcript may contribute to activation of the NOTCH2 pathway in GT and drive tumor development. The high frequency of this translocation in GT of the upper digestive track suggest that detection of nuclear NOTCH2 expression may be useful diagnostic biomarker of these tumors.

Background Human papillomavirus (HPV) infection is more frequent in men having sex with men (MSM) who are living with human immunodeficiency virus (HIV) than in MSM without HIV. There are currently no data regarding HPV infections in preexposure prophylaxis (PrEP)-using MSM. Methods MSM living without HIV who were enrolled in the Agence Nationale de Recherches sur le SIDA et les Hépatites Virales "Intervention Préventive de l'Exposition aux Risques avec et pour les hommes Gays" PrEP study were prospectively enrolled. Anal, penile, and oral samples were collected at baseline and every 6 months for HPV detection and genotyping. Anal swabs for cytology were obtained at baseline and at 24 months. Results We enrolled 162 participants. The prevalences of any HPV genotypes at baseline were 92%, 32%, and 12% at the anal, penile, and oral sites, respectively. High-risk (HR) HPV genotypes were observed in 84%, 25%, and 10% of anal, penile, and oral baseline samples, respectively. Nonavalent HPV vaccine genotypes were observed in 77%, 22%, and 6% of anal, penile, and oral baseline samples, respectively. Multiple infections were observed in 76%, 17%, and 3% of cases at the anal, penile, and oral sites, respectively. The most frequent HR genotypes were HPV 53, 51, and 16 in anal samples; HPV 33, 39, and 73 in penile samples; and HPV 66 in oral samples. The incidence of any HPV genotype at the anal site was 86.2/1000 person-months and the incidence of HR-HPV genotypes was 72.3/1000 person-months. The baseline cytology was normal in 32% of cases and was classified as atypical squamous cells of undetermined significance, low-grade squamous intra-epithelial lesion, high-grade squamous intra-epithelial lesion (HSIL), and atypical squamous cells that cannot exclude HSIL in 23%, 40%, 5%, and 1% of cases, respectively. Conclusions PrEP users have a similar risk of HPV infection as MSM living with HIV and the risk is much higher than that previously reported in MSM living without HIV.