Jean-François Fléjou

ENDOSONOGRAPHY: PROMISING METHOD FOR DIAGNOSIS OF EXTRAHEPATIC CHOLESTASIS

Endosonography, ultrasonography, and computed tomography (CT) were carried out prospectively in 52 patients with extrahepatic cholestasis. 35 patients had extrahepatic biliary obstructions (21 tumorous, 14 non-tumorous) and 17, with recent gallstone migration within the bile duct, had no extrahepatic obstruction at the time of investigation. The definitive diagnosis was established by surgery (in 39 patients), by transendoscopic sphincterotomy (11 patients), or by retrograde biliary opacification (2 patients). Endosonography was significantly more sensitive than ultrasonography or CT (100% vs 80% and 83%, respectively) in making a positive diagnosis of obstruction. Endosonography was also significantly more accurate than ultrasonography or CT (97% vs 49% and 66%) in diagnosing the cause of the obstruction and more effective in the assessment of the locoregional spread of tumorous obstructions (75% vs 38% and 62%). Thus, endosonography was superior to ultrasonography and CT in the diagnosis and staging of biliary obstructions.

The ciliated hepatic foregut cyst, an unusual bronchiolar foregut malformation: A histological, histochemical, and immunohistochemical study of 7 cases

The ciliated hepatic foregut cyst is an unusual solitary cystic lesion of the liver. In a series of 7 cases of hepatic ciliated cysts, we performed a histological, histochemical, and immunohistochemical study to better define the histogenesis of this rare entity. The patients were 4 women and 3 men, aged 39 to 75 years. Four patients presented with abdominal pain. In 3 cases the cyst was discovered incidentally on ultrasonography. The cysts measured from 1 to 4 cm in diameter. Microscopically, the lining of the columnar epithelium was composed of ciliated cells and mucin secreting goblet cells. The wall was composed of bands of smooth-muscle fibers surrounded by an outer fibrous capsule. The goblet cells stained with PAS, alcian blue, and high-iron diamine. The immunohistochemical study showed that endocrine cells were present within the cyst epithelium, positive for chromogranin, synaptophysin, bombesin, and calcitonin, and negative for serotonin, somatostatin, glucagon, insulin, gastrin, and pancreatic polypeptide. In all the cases, immunoreactivity of some cells for CC10 strongly suggested the presence of Clara cells. Our study shows that the epithelium lining ciliated hepatic foregut cysts has histological, histochemical, and immunohistochemical features similar to those observed in the bronchiolar epithelium. This lesion is a developmental ventral foregut abnormality that could arise from a bronchiolar bud of the tracheobronchial diverticulum.

Knockout of Insulin-Like Growth Factor-1 Receptor Impairs Distal Lung Morphogenesis

Background Insulin-like growth factors (IGF-I and -II) are pleiotropic regulators of somatic growth and development in vertebrate species. Endocrine and paracrine effects of both hormones are mediated by a common IGF type 1 receptor (IGF-1R). Lethal respiratory failure in neonatal IGF-1R knockout mice suggested a particular role for this receptor in pulmonary development, and we therefore investigated the consequences of IGF-1R inactivation in lung tissue. Methods and Findings We first generated compound heterozygous mutant mice harboring a hypomorphic (Igf1rneo) and a null (Igf1r−) allele. These IGF-1Rneo/− mice express only 22% of normal IGF-1R levels and are viable. In adult IGF-1Rneo/− mice, we assessed lung morphology and respiratory physiology and found normal histomorphometric characteristics and normal breathing response to hypercapnia. We then generated homozygous IGF-1R knockout mutants (IGF-1R−/−) and analyzed their lung development during late gestation using histomorphometric and immunohistochemical methods. IGF-1R−/− embryos displayed severe lung hypoplasia and markedly underdeveloped diaphragms, leading to lethal neonatal respiratory distress. Importantly, IGF-1R−/− lungs from late gestation embryos were four times smaller than control lungs and showed markedly thickened intersaccular mesenchyme, indicating strongly delayed lung maturation. Cell proliferation and apoptosis were significantly increased in IGF-1R−/− lung tissue as compared with IGF-1R+/+ controls. Immunohistochemistry using pro-SP-C, NKX2-1, CD31 and vWF as markers revealed a delay in cell differentiation and arrest in the canalicular stage of prenatal respiratory organ development in IGF-1R−/− mutant mice. Conclusions/Significance We found that low levels of IGF-1R were sufficient to ensure normal lung development in mice. In contrast, complete absence of IGF-1R significantly delayed end-gestational lung maturation. Results indicate that IGF-1R plays essential roles in cell proliferation and timing of cell differentiation during fetal lung development.

Associated primary esophageal and lung carcinoma: A study of 39 patients

From 1979 to 1992, of 1,294 patients with esophageal squamous cell carcinoma, 39 patients (3.2%) (38 male patients, 1 female patient; mean age, 58 years) had associated primary lung carcinoma. Criteria for the diagnosis of primary lung carcinoma were: (1) non-squamous cell carcinoma tumors, (2) tumors existing before the esophageal squamous cell carcinoma, and (3) solitary squamous cell carcinoma presenting with endobronchial involvement. The two tumors were observed synchronously in 22 patients (56%) and metachronously in 17, with a mean tumor-free interval of 46 months (range, 18 to 77 months). In patients with synchronous disease, 10 underwent nonoperative treatment or a palliative surgical procedure, and 12 (55%) underwent a curative operation. In patients with metachronous disease, a curative operation was performed in all for the first tumor and in 9 (53%) for the second tumor. The overall postoperative mortality rate was 15%. Two patients (10%) died after the curative operation. None of the patients died who underwent curative esophagectomy combined with lobectomy. For the patients with synchronous disease, the 5-year survival rate was 11% in those who underwent a curative operation, and the longest survival in those who received palliative treatment was 18 months. For the patients with metachronous disease, the 5-year survival rates from the date of the diagnosis of the second tumor were 17% for those who had a curative operation and 11% for those who received palliative treatment.(ABSTRACT TRUNCATED AT 250 WORDS)

Pseudotumor developing in heterotopic pancreas

Abstract. Cystic dystrophy in heterotopic pancreas (CDHP) is characterized by the presence of cystic formations surrounded by inflammation and scarring. It usually involves the duodenal wall and can be responsible for strictures and pain. The diagnosis of this disorder was previously based on pancreatoduodenectomy specimens removed for a suspected pancreatic tumor. Six cases were observed in young men (mean age 40 years) between 1989 and 1993. Computed tomography (CT) and endoscopic ultrasonography (EUS) features allowed definitive preoperative diagnosis of CDHP. After surgical resection of the tissue-bearing segments that included five pancreatoduodenectomies and one antrectomy, symptoms disappeared in all patients. Patients were followed 2 to 45 months; one patient experienced recurrence of pain and hyperamylasemia 17 months after surgery. The preoperative diagnosis of CDHP is presently possible because of modern imaging procedures and improved knowledge of specific signs. Resection is the most appropriate treatment.

Deficiency in type 1 insulin-like growth factor receptor in mice protects against oxygen-induced lung injury

BackgroundCellular responses to aging and oxidative stress are regulated by type 1 insulin-like growth factor receptor (IGF-1R). Oxidant injury, which is implicated in the pathophysiology of a number of respiratory diseases, acutely upregulates IGF-1R expression in the lung. This led us to suspect that reduction of IGF-1R levels in lung tissue could prevent deleterious effects of oxygen exposure.MethodsSince IGF-1R null mutant mice die at birth from respiratory failure, we generated compound heterozygous mice harboring a hypomorphic (Igf-1rneo) and a knockout (Igf-1r-) receptor allele. These IGF-1Rneo/- mice, strongly deficient in IGF-1R, were subjected to hyperoxia and analyzed for survival time, ventilatory control, pulmonary histopathology, morphometry, lung edema and vascular permeability.ResultsStrikingly, after 72 h of exposure to 90% O2, IGF-1Rneo/- mice had a significantly better survival rate during recovery than IGF-1R+/+ mice (77% versus 53%, P < 0.05). The pulmonary injury was consistently, and significantly, milder in IGF-1Rneo/- mice which developed conspicuously less edema and vascular extravasation than controls. Also, hyperoxia-induced abnormal pattern of breathing which precipitated respiratory failure was elicited less frequently in the IGF-1Rneo/- mice.ConclusionTogether, these data demonstrate that a decrease in IGF-1R signaling in mice protects against oxidant-induced lung injury.

Activation of ras oncogene in livers with cirrhosis

Activation of cellular oncogenes and inactivation of anti-oncogenes have been postulated as important mechanisms during hepatocarcinogenesis. This study was conducted to detect abnormal levels of several proto-oncogenes (c-jun, c-fos, c-H-ras) and of the p53 and the alpha-fetoprotein gene in the liver during cirrhosis, a pathological process which predisposes to the development of hepatocarcinoma. Liver tissue from 11 patients with cirrhosis of different etiologies, and seven histologically normal liver fragments taken at the periphery of benign liver tumors of metastases were studied. Transcripts of the various oncogenes and of the alpha-fetoprotein gene were detected by in situ hybridization, and the p53 protein was revealed by immunocytochemistry. No overexpression of any of the mRNA tested or of the p53 protein was found in histologically normal liver in contact with benign or metastatic tumors. In contrast, 10 of the 11 specimens with cirrhosis (90.9%) displayed abnormally high levels of c-H-ras transcripts. Five samples with cirrhosis revealed a moderate increase in the level of c-fos mRNA. Only one case and two cases, respectively, exhibited increased levels of c-jun and alpha-fetoprotein mRNA. No cases were positive for the p53 antigen. Liver-cell proliferation, as assessed by immunocytochemistry with the Ki 67 monoclonal antibody, was low in both the group with cirrhosis and the control groups (0.49% and 0.55% positive cells, respectively). These data demonstrate that activation of c-H-ras mRNA is an almost constant finding in hepatocytes of livers with cirrhosis. This gene overexpression is not linked to hepatocellular proliferation.(ABSTRACT TRUNCATED AT 250 WORDS)

SMAD4 protein expression and cell proliferation in colorectal adenocarcinomas.

The TGFβ signalling pathway is a growth inhibitor system that operates in both normal and tumour cells. Alterations to components of this pathway, including SMAD4, result in resistance to growth inhibition and uncontrolled proliferation. The aim of this study was to analyse the relationships between SMAD4, a key protein in the growth-inhibiting TGFβ pathway; cell proliferation proteins Ki67, p27 and S-phase kinase-associated protein 2 (SKP2); and mismatch repair (MMR) proteins as well as prognostic indicators in colorectal adenocarcinomas. A series of 230 sporadic colorectal adenocarcinomas were studied using tissue microarrays by immunohistochemistry for SMAD4, Ki67, p27, SKP2 and MMR protein (hMLH1, hMSH2 and hMSH6) expression. Protein expression was analysed with respect to pathological prognostic criteria. Loss of SMAD4 nuclear expression (27/230, 12%) correlated with the presence of lymph node metastases, MMR protein expression and the absence of p27 in tumour cells (p = 0.04, p = 0.08 and p = 0.03, respectively). A high Ki67 index did not correlate with SMAD4 expression; however, it did correlate with moderate or poor histological differentiation, SKP2 expression and aberrant or absent MMR protein expression (p = 0.02, p < 0.01 and p < 0.01, respectively). In conclusion, the results of our study suggest that the loss of SMAD4, occurring in 12% of colorectal adenocarcinomas, correlated with the presence of lymph node metastases and absence of p27 expression but not with high cellular proliferation. However, high proliferation correlated with SKP2 and aberrant MMR protein expression. Although the advantage of immunohistochemistry is high throughput, our results allow only an initial evaluation, and subsequent studies, including genetic analyses, are required.

The Balance Between Cytotoxic T-cell Lymphocytes and Immune Checkpoint Expression in the Prognosis of Colon Tumors

Background Immune checkpoint (ICK) expression might represent a surrogate measure of tumor-infiltrating T cell (CTL) exhaustion and therefore be a more accurate prognostic biomarker for colorectal cancer (CRC) patients than CTL enumeration as measured by the Immunoscore. Methods The expression of ICKs, Th1, CTLs, cytotoxicity-related genes, and metagenes, including Immunoscore-like metagenes, were evaluated in three independent cohorts of CRC samples (260 microsatellite instable [MSI], 971 non-MSI). Their associations with patient survival were analyzed by Cox models, taking into account the microsatellite instability (MSI) status and affiliation with various Consensus Molecular Subgroups (CMS). PD-L1 and CD8 expression were examined on a subset of tumors with immunohistochemistry. All statistical tests were two-sided. Results The expression of Immunoscore-like metagenes was statistically significantly associated with improved outcome in non-MSI tumors displaying low levels of both CTLs and immune checkpoints (ICKs; CMS2 and CMS3; hazard ratio [HR] = 0.63, 95% confidence interval [CI] = 0.43 to 0.92, P = .02; and HR = 0.55, 95% CI = 0.34 to 0.90, P = .02, respectively), but clearly had no prognostic relevance in CRCs displaying higher levels of CTLs and ICKs (CMS1 and CMS4; HR = 0.46, 95% CI = 0.10 to 2.10, P = .32; and HR = 1.13, 95% CI = 0.79 to 1.63, P = .50, respectively), including MSI tumors. ICK metagene expression was statistically significantly associated with worse prognosis independent of tumor staging in MSI tumors (HR = 3.46, 95% CI = 1.41 to 8.49, P = .007). ICK expression had a negative impact on the proliferation of infiltrating CD8 T cells in MSI neoplasms (median = 0.56 in ICK low vs median = 0.34 in ICK high, P = .004). Conclusions ICK expression cancels the prognostic relevance of CTLs in highly immunogenic colon tumors and predicts a poor outcome in MSI CRC patients.

Prevalence and Risk Factors for Anal Human Papillomavirus Infection in Human Immunodeficiency Virus–Positive Men Who Have Sex with Men

Background We assessed prevalence and risk factors for anal human papillomavirus (HPV) in human immunodeficiency virus (HIV)-positive men who have sex with men (MSM), who are at high-risk of HPV-related anal cancer. Methods APACHES is a multicentric, prospective study of anal HPV infection and lesions in HIV-positive MSM aged ≥35 years. At baseline, participants underwent anal swabs for HPV and cytology, plus high-resolution anoscopy. High-risk HPV (HR-HPV) was tested by Cobas4800, with genotyping of HR-HPV positives by PapilloCheck. Results Among 490 participants, prevalence of HPV16 and HR-HPV was 29% and 70%, respectively, and did not differ significantly by age, sexual behavior, or markers of HIV or immune deficiency. Smoking was the only, albeit weak (odds ratio, 1.8; 95% confidence interval, 1.2-2.7), predictor of HR-HPV. High-risk HPV and HPV16 prevalence increased strongly with anal diagnosis severity, both by worse cytological/histological (composite) diagnosis at APACHES baseline and worse historical diagnosis. HPV16 rose from 19% among participants who were negative for lesions to 63% among participants with high-grade lesions. In contrast, non-HPV16 HR-HPVs were less prevalent in high-grade (37%) than negative (64%) composite diagnosis, and their causal attribution was further challenged by multiple HPV infections. Conclusions Human papillomavirus 16 is ubiquitously frequent among human immunodeficiency virus -positive men having sex with men, and more strongly associated with high-grade anal lesions than other high-risk types, confirming it as a target for anal cancer prevention.