Molecular and clinical diversity in primary central nervous system lymphoma

BACKGROUND

Primary central nervous system lymphoma (PCNSL) is a rare and distinct entity within diffuse large B-cell lymphoma presenting with variable response rates probably to underlying molecular heterogeneity.

PATIENTS AND METHODS

To identify and characterize PCNSL heterogeneity and facilitate clinical translation, we carried out a comprehensive multi-omic analysis [whole-exome sequencing, RNA sequencing (RNA-seq), methylation sequencing, and clinical features] in a discovery cohort of 147 fresh-frozen (FF) immunocompetent PCNSLs and a validation cohort of formalin-fixed, paraffin-embedded (FFPE) 93 PCNSLs with RNA-seq and clinico-radiological data.

RESULTS

Consensus clustering of multi-omic data uncovered concordant classification of four robust, non-overlapping, prognostically significant clusters (CS). The CS1 and CS2 groups presented an immune-cold hypermethylated profile but a distinct clinical behavior. The 'immune-hot' CS4 group, enriched with mutations increasing the Janus kinase (JAK)-signal transducer and activator of transcription (STAT) and nuclear factor-κB activity, had the most favorable clinical outcome, while the heterogeneous-immune CS3 group had the worse prognosis probably due to its association with meningeal infiltration and enriched HIST1H1E mutations. CS1 was characterized by high Polycomb repressive complex 2 activity and CDKN2A/B loss leading to higher proliferation activity. Integrated analysis on proposed targets suggests potential use of immune checkpoint inhibitors/JAK1 inhibitors for CS4, cyclin D-Cdk4,6 plus phosphoinositide 3-kinase (PI3K) inhibitors for CS1, lenalidomide/demethylating drugs for CS2, and enhancer of zeste 2 polycomb repressive complex 2 subunit (EZH2) inhibitors for CS3. We developed an algorithm to identify the PCNSL subtypes using RNA-seq data from either FFPE or FF tissue.

CONCLUSIONS

The integration of genome-wide data from multi-omic data revealed four molecular patterns in PCNSL with a distinctive prognostic impact that provides a basis for future clinical stratification and subtype-based targeted interventions.

P11.09.B Chemotherapy is an efficient treatment in primary CNS MALT lymphoma

Background

Mucosae-associated lymphoid tissue (MALT) lymphomas are a rare and still poorly understood form of primary central nervous system lymphoma (PCNSL). The aim of this study was to better describe these tumors and their management, and to better appreciate their long-term prognosis after treatment.

Material and Methods

Adult immunocompetent patients with primary CNS MALT lymphoma (PCNSML) were retrospectively selected from the database on PCNSL of the Pitié-Salpêtrière Hospital. All cases had double-read for pathology.

Results

Eleven PCNSML representing 1.7% of the 662 PCNSL included in the database were selected, There were 9 women and two men, all immunocompetent. Their median age was 56 years (min 29; max 78). The median time from first symptoms to diagnosis was 13 months and the median KPS at diagnosis was 90. Location was dural in 8 cases, suggestive of meningioma in 7 cases and of subdural hematoma in 1 case, and parenchymal in 3 cases. The disease was unifocal/localized in 4 cases and multifocal/diffuse in 7 cases. In 3 cases, it was the second reading that allowed making the diagnosis. In first-line treatment, all patients received chemotherapy (CT): “systemic” CT, i.e usually used in systemic MALT lymphomas, in 7 cases (n=7) and “CNS” CT, i.e usually used in CNS lesions in 4 cases. CT was preceded by surgery in 4 cases. No patient received radiotherapy in first line. According to the IPCG (International PCNSL Collaborative Group) criteria, the overall response rate was 7/11 (64%). At latest news, 5 patients had a persistent contrast enhancement, stable without any treatment since a median of 57 months, raising the question of complete response despite persisting contrast enhancement. No patient developed neurotoxicity except for one of the 2 patients who subsequently received radiotherapy. The median follow-up was 109 months. The median progression-free survival was 78.0 months (95% CI [43.4;NA[) and the 10-year overall survival rate was 90% (95% CI [0.7;1[).

Conclusion

This series confirms the classical clinical and radiological presentation of PCNSML. Compared to the literature where the treatment was based on radiotherapy in almost two thirds of cases, the therapeutic approach presented here appears unconventional. This is the first series demonstrating that chemotherapy is an efficient treatment in PCNSML, with an excellent long-term outcome and the absence of neurotoxicity, and calling into question the relevance of the IPCG criteria for the evaluation of their therapeutic response.

Comparison of HIV-Infected and Noninfected Patients Undergoing Bariatric Surgery: The ObeVIH Study

OBJECTIVE

The aim of this study was to compare clinical characteristics and adipose/liver tissue histology analysis in HIV-infected and HIV-uninfected subjects undergoing bariatric surgery.

DESIGN

This was a cross-sectional study of HIV-infected subjects undergoing single-port sleeve gastrectomy with prospective enrolment and frequency age (±5 years), sex, and body mass index (BMI, ± 5 kg/m2) matched on HIV-uninfected subjects.

METHODS

This study was conducted at a single clinical site at Pitié-Salpêtrière hospital-Paris-France comprising 19 HIV-uninfected and 21 HIV-infected subjects with plasma VL < 20 copies/mL, all with a BMI > 40 kg/m2 or >35 kg/m2 with comorbidities. Histology of subcutaneous and visceral abdominal adipose tissue (SCAT/VAT) and liver biopsies was collected during single-port sleeve gastrectomy. Outcomes included anthropometric characteristics, comorbidities, cardiovascular parameters, adipose tissue, and liver histology.

RESULTS

The age of HIV-infected participants was (median, interquartile range IQR) 48 y (42-51), with 76.2% females, a BMI of 41.4 kg/m2 (37.3-44.4), an antiretroviral duration of 16 y (8-21), current integrase strand transfer inhibitor (INSTI)-based regimen in 15 participants and non-INSTI regimen in 6 participants, and a CD4 count of 864/mm3 (560-1066). The age of controls was 43 y (37-51), with 78.9% females and a BMI of 39.2 kg/m2 (36.3-42.6). Anthropometric characteristics, comorbidities, and cardiovascular parameters did not differ according to HIV status and INSTI treatment. The number of macrophage crown-like structures in SCAT was lower in INSTI-treated participants than in HIV-uninfected participants (P = 0.02) and non-INSTI-treated HIV-infected subjects (P = 0.07). Hepatic steatosis and liver disease severity global score were lower in INSTI-treated participants than in non-INSTI-treated HIV-infected participants (P = 0.05 and P = 0.04, respectively).

CONCLUSIONS

HIV-infected and HIV-uninfected subjects undergoing bariatric surgery presented a similar profile regarding anthropometric measures, cardiovascular parameters, and comorbidities. However, INSTI-treated participants presented milder SCAT and liver alterations than non-INSTI-treated participants.

HCV cure: an appropriate moment to reduce cannabis use in people living with HIV? (ANRS CO13 HEPAVIH data)

BACKGROUND

Thanks to direct-acting antivirals, hepatitis C virus (HCV) infection can be cured, with similar rates in HCV-infected and HIV-HCV co-infected patients. HCV cure is likely to foster behavioral changes in psychoactive substance use, which is highly prevalent in people living with HIV (PLWH). Cannabis is one substance that is very commonly used by PLWH, sometimes for therapeutic purposes. We aimed to identify correlates of cannabis use reduction following HCV cure in HIV-HCV co-infected cannabis users and to characterize persons who reduced their use.

METHODS

We used data collected on HCV-cured cannabis users in a cross-sectional survey nested in the ANRS CO13 HEPAVIH cohort of HIV-HCV co-infected patients, to perform logistic regression, with post-HCV cure cannabis reduction as the outcome, and socio-behavioral characteristics as potential correlates. We also characterized the study sample by comparing post-cure substance use behaviors between those who reduced their cannabis use and those who did not.

RESULTS

Among 140 HIV-infected cannabis users, 50 and 5 had reduced and increased their use, respectively, while 85 had not changed their use since HCV cure. Cannabis use reduction was significantly associated with tobacco use reduction, a decrease in fatigue level, paying more attention to one's dietary habits since HCV cure, and pre-HCV cure alcohol abstinence (p = 0.063 for alcohol use reduction).

CONCLUSIONS

Among PLWH using cannabis, post-HCV cure cannabis reduction was associated with tobacco use reduction, improved well-being, and adoption of healthy behaviors. The management of addictive behaviors should therefore be encouraged during HCV treatment.

[Enteroviral infections in adults treated with rituximab: A new case of chronic meningitis and myofasciitis and literature review]

INTRODUCTION

Chronic enterovirus infections can occur in primary immunodeficiency with hypogammaglobulinemia. They usually associate meningitis and myofasciitis. Such infections have also been described in adults with rituximab-induced hypogammaglobulinemia.

CASE REPORT

We report the case of a 33-year-old woman who was given rituximab for immune thrombocytopenia and developed rituximab-induced hypogammaglobulinemia (IgG 4.4g/L). One year after the last rituximab infusion, she developed lower limbs myofasciitis, followed two months later by a chronic lymphocytic meningitis. PCR in the serum and the cerebrospinal fluid at the time of the meningitis and the myofasciitis were positive to the same enterovirus (echovirus 11) while it was negative in the fascia biopsy. Under treatment with intravenous immunoglobulins, all symptoms and laboratory abnormalities improved and enterovirus PCR became negative.

CONCLUSION

We report a case of chronic enterovirus infection associating meningitis and myofasciitis in an adult with rituximab-induced hypogammaglobulinemia. Outcome was favorable under treatment with intravenous immunoglobulins.

[Rosai-Dorfman disease: Diagnosis and therapeutic challenges]

Rosai-Dorfman disease (RDD) was first described by the French pathologist Paul Destombes in 1965. It frequently affects children or young adults and is characterized by the presence of large histiocytes with emperipolesis. More than 50 years after this first description, the pathogenesis of this rare disease is still poorly understood. The revised classification of histiocytoses published in 2016 identified various forms of RDD, from familial RDD to IgG4-associated RDD. Almost 90% of the patients with RDD have cervical lymph nodes involvement although all the organs may virtually be involved. Outcomes are typically favorable. Treatments may be necessary in case of compression or obstruction, and are not well codified. The main therapeutic strategies rely on surgery, radiotherapy, steroids, immunosuppressive drugs or interferon-alpha and cladribine.

Primary hepatic angiosarcoma and liver transplantation: Radiological, surgical, histological findings and clinical outcome

Angiosarcoma is a rare type of soft tissue sarcoma that accounts for less than 1% of all sarcomas and only 2% of all primary hepatic tumours. Thorotrast, arsenic, and vinyl chloride monomer are frequently listed as occupational exposure risks. The estimated latency is long (10-40 years) in occupational cases and very long (60 years or more) in non-occupational cases. The symptoms and CT-scan appearance of hepatic angiosarcoma (HAS) are non-specific. We present a case of a 65-year-old Caucasian male with history of cryptogenic cirrhosis, low alpha-foetoprotein levels and a single, 4-cm nodule of potential atypical hepatocellular carcinoma (no washout at MRI and CT-scan) in segment VIII. Laparoscopic radiofrequency ablation (a biopsy of the neoplastic lesion was technically impossible) was performed, followed by liver transplantation (LT) 6 months later. High-grade multifocal HAS was found in the explanted liver, with extensive involvement of the venous portal structures. No complications were observed during the postoperative course, and initial immunosuppression included tacrolimus, mycophenolate mofetil and corticosteroids. Because of the histological findings, tacrolimus was switched to everolimus as the main immunosuppressive drug one month after LT. Despite this conversion, the patient developed bone metastases 3 months after LT and peritoneal carcinosis one month later. This case report suggests that everolimus conversion does not inhibit the development of tumour metastases. Consequently, HAS remains an absolute contraindication to LT because of the poor outcome. If LT has been performed for incidental HAS, new molecular therapies (e.g. vascular endothelial growth factor antagonists) should be considered immediately after LT to improve the outcome.

Unique case report of a chromomycosis and Listeria in soft tissue and cerebellar abscesses after kidney transplantation

Background

Chromomycosis is a rare mycotic infection encountered in tropical and subtropical regions. The disease presents as a slowly-evolving nodule that can become infected with bacteria. Here, we describe a unique association of abscesses caused by a chromomycosis and Listeria monocytogenes in a kidney transplant recipient, and didactically expose how the appropriate diagnosis was reached.

Case presentation

A 49-year old male originating from the Caribbean presented a scalp lesion which was surgically removed in his hometown where it was misdiagnosed as a sporotrichosis on histology, 3 years after he received a kidney transplant. He received no additional treatment and the scalp lesion healed. One year later, an abscess of each thigh due to both F. pedrosoi and L. monocytogenes was diagnosed in our institution. A contemporary asymptomatic cerebellar abscess was also found by systematic MRI. An association of amoxicillin and posaconazole allowed a complete cure of the patient without recurring to surgery. Histological slides from the scalp lesion were re-examined in our institution and we retrospectively concluded to a first localisation of the chromomycosis. We discuss the possible pathophysiology of this very unusual association.

Conclusion

In this case of disseminated listeriosis and chromomycosis, complete cure of the patients could be reached with oral anti-infectious treatment only.

[Sarcoidosis flare after autologous stem cell transplantation: An immune paradox?]

INTRODUCTION

Sarcoidosis is a systemic granulomatous disorder of unknown cause. Apparition or flare of previously diagnosed sarcoidosis following hematopoietic stem cell transplantation (HSCT) has rarely been reported.

OBSERVATION

We report a 62-year-old woman who presented a radiological flare of sarcoidosis post-autologous stem cell transplantation for a POEMS syndrome. Imaging findings and lymph node histology, which revealed non-caseating granuloma, were consistent with the sarcoidosis diagnosis. The patient was asymptomatic and was kept free of treatment.

CONCLUSION

Sarcoidosis must be considered ahead of compatible clinicoradiological presentation occurring after HSCT. Sarcoidosis can mimic metastatic cancer or lymphatic relapse. Tissue biopsies and exclusion of differential diagnosis of granuloma diseases are warranted to confirm sarcoidosis diagnosis.

[Neurosarcoidosis: Diagnosis and therapeutic issues]

Neurological localizations of sarcoidosis are heterogeneous and may affect virtually every part of the central or peripheral nervous system. They are often the inaugural manifestation of sarcoidosis. The diagnosis may be difficult due to the lack of extra-neurological localization. Diagnosis may be discussed in the presence of an inflammatory neurological disease, in particular in case of suggestive radiological or biological pattern. Cerebrospinal fluid analysis shows lymphocytic pleiocytosis, often with low glucose level. The diagnosis relies on a clinical, biological and radiological presentation consistent with neurosarcoidosis, the presence of non-caseating granuloma and exclusion of differential diagnoses. Screening for other localizations of sarcoidosis, in particular cardiac disease may be obtained during neurosarcoidosis. The treatment of neurosarcoidosis relies on corticosteroids although immunosuppressive drugs are usually added because of the chronic course of this condition and to limit the side effects of steroids. Treatments and follow-up may be prolonged because of the high rate of relapses.

Diagnostic performance of FibroTest, SteatoTest and ActiTest in patients with NAFLD using the SAF score as histological reference

BACKGROUND

Blood tests of liver injury are less well validated in non-alcoholic fatty liver disease (NAFLD) than in patients with chronic viral hepatitis.

AIMS

To improve the validation of three blood tests used in NAFLD patients, FibroTest for fibrosis staging, SteatoTest for steatosis grading and ActiTest for inflammation activity grading.

METHODS

We pre-included new NAFLD patients with biopsy and blood tests from a single-centre cohort (FibroFrance) and from the multicentre FLIP consortium. Contemporaneous biopsies were blindly assessed using the new steatosis, activity and fibrosis (SAF) score, which provides a reliable and reproducible diagnosis and grading/staging of the three elementary features of NAFLD (steatosis, inflammatory activity) and fibrosis with reduced interobserver variability. We used nonbinary-ROC (NonBinAUROC) as the main endpoint to prevent spectrum effect and multiple testing.

RESULTS

A total of 600 patients with reliable tests and biopsies were included. The mean NonBinAUROCs (95% CI) of tests were all significant (P < 0.0001): 0.878 (0.864-0.892) for FibroTest and fibrosis stages, 0.846 (0.830-0.862) for ActiTest and activity grades, and 0.822 (0.804-0.840) for SteatoTest and steatosis grades. FibroTest had a higher NonBinAUROC than BARD (0.836; 0.820-0.852; P = 0.0001), FIB4 (0.845; 0.829-0.861; P = 0.007) but not significantly different than the NAFLD score (0.866; 0.850-0.882; P = 0.26). FibroTest had a significant difference in median values between adjacent stage F2 and stage F1 contrarily to BARD, FIB4 and NAFLD scores (Bonferroni test P < 0.05).

CONCLUSIONS

In patients with NAFLD, SteatoTest, ActiTest and FibroTest are non-invasive tests that offer an alternative to biopsy, and they correlate with the simple grading/staging of the SAF scoring system across the three elementary features of NAFLD: steatosis, inflammatory activity and fibrosis.

2016 Comprehensive Update of the Banff Working Group on Liver Allograft Pathology: Introduction of Antibody-Mediated Rejection

The Banff Working Group on Liver Allograft Pathology reviewed and discussed literature evidence regarding antibody-mediated liver allograft rejection at the 11th (Paris, France, June 5-10, 2011), 12th (Comandatuba, Brazil, August 19-23, 2013), and 13th (Vancouver, British Columbia, Canada, October 5-10, 2015) meetings of the Banff Conference on Allograft Pathology. Discussion continued online. The primary goal was to introduce guidelines and consensus criteria for the diagnosis of liver allograft antibody-mediated rejection and provide a comprehensive update of all Banff Schema recommendations. Included are new recommendations for complement component 4d tissue staining and interpretation, staging liver allograft fibrosis, and findings related to immunosuppression minimization. In an effort to create a single reference document, previous unchanged criteria are also included.

Endocrine Manifestations in a Monocentric Cohort of 64 Patients With Erdheim-Chester Disease

CONTEXT

Erdheim-Chester disease (ECD) is a rare non-Langerhans cell histiocytosis, characterized by infiltration of foamy histiocytes in multiple organs. Endocrine involvement has mostly been described in case reports.

OBJECTIVE

We performed systematic endocrine evaluation in a large cohort of patients with ECD.

DESIGN

This was a single-center observational study conducted between October 2007 and May 2013.

SETTING

The evaluation was conducted in Pitié-Salpêtrière Hospital (Paris, France), a tertiary care hospital.

PATIENTS

Sixty-four consecutive patients with ECD (sex ratio, 3.6; mean age, 57.6 years [range, 20-80 years]). Thirty-six patients had follow-up assessments.

INTERVENTIONS

There were no interventions.

MAIN OUTCOME MEASURES

Clinical, biological, and morphological evaluations of pituitary, gonadal, adrenal, and thyroid functions, as well as metabolic evaluation, were performed.

RESULTS

Diabetes insipidus was found in 33.3% of patients, frequently as the first manifestation of ECD. Anterior pituitary dysfunction was found in 91.3% of patients with full anterior pituitary evaluation, including somatotropic deficiency (78.6%), hyperprolactinemia (44.1%), gonadotropic deficiency (22.2%), thyrotropic deficiency (9.5%), and corticotropic deficiency (3.1%). Thirty-five patients (54.7%) had ≥2 anterior pituitary dysfunctional axes, rising to 69.6% (16 of 23) when only patients with complete evaluations were considered. Two patients had panhypopituitarism. Infiltration of the pituitary and stalk was found with magnetic resonance imaging in 24.4% of patients. Testicular insufficiency was found in 53.1% of patients, with sonographic testicular infiltration in 29% of men, mostly bilateral. Computed tomography adrenal infiltration was found in 39.1% of patients, and 1 case of adrenal insufficiency was observed. No patient was free of endocrine hormonal or morphological involvement. Endocrine dysfunctions were most often permanent, and new deficits appeared during follow-up.

CONCLUSION

Endocrine involvement is very frequent in ECD and should be evaluated carefully at diagnosis and during follow-up.

Performance and limitations of steatosis biomarkers in patients with nonalcoholic fatty liver disease

BACKGROUND

Several steatosis biomarkers are available with limited independent validation.

AIM

To determine diagnostic value and limitations of several steatosis biomarkers using liver biopsy as reference standard in a large cohort of patients with suspected NAFLD.

METHODS

Three hundred and twenty-four consecutive liver biopsies were included. Histological steatosis was categorised as none (<5%), mild (5-33%), moderate (33-66%) and severe (>66%). Five steatosis biomarkers were measured: fatty liver index (FLI), NAFLD liver fat score (NAFLD-LFS), hepatic steatosis index (HSI), visceral adiposity index (VAI) and triglyceride × glucose (TyG) index.

RESULTS

Steatosis grades prevalence was: none 5%, mild 39%, moderate 30% and severe 27%. Except for VAI, the steatosis biomarkers showed a linear trend across the steatosis grades. However, their correlation with the histological amount of steatosis was only weak-moderate. All steatosis biomarkers had an adequate diagnostic accuracy for the presence of steatosis: AUROCs for FLI, LFS, HSI, VAI and TyG were 0.83, 0.80, 0.81, 0.92 and 0.90. However, their ability to quantify steatosis was poor: none of them distinguished between moderate and severe steatosis and the AUROCs for predicting steatosis >33% were 0.65, 0.72, 0.65, 0.59 and 0.59 for FLI, LFS, HSI, VAI and TyG. Both fibrosis and inflammation significantly confounded the association between steatosis biomarkers and steatosis. The steatosis biomarkers were all correlated with HOMA-IR, independent from histological steatosis.

CONCLUSIONS

All five steatosis biomarkers can diagnose steatosis and are correlated with insulin resistance. They are confounded by fibrosis and inflammation, and do not accurately quantify steatosis; this may limit their clinical utility. More research is needed to identify truly independent and quantitative markers of steatosis.

Liver preservation with SCOT 15 solution decreases posttransplantation cholestasis compared with University of Wisconsin solution: a retrospective study

BACKGROUND

SCOT 15 is a new solution to preserve abdominal organs for transplantation. Its principal characteristic is the use of polyethylene glycol. Herein We report our experience using SCOT 15 compared with the reference University of Wisconsin (UW) solution for hepatic transplantation.

METHODS

We compared 2 groups: SCOT 15 (n = 33; 2009-2010) versus UW (n = 34; 2008-2010), which were paired for cold and warm ischemic times, donor ages, and graft weights. Endpoints were biologic tests in the first 2 months after the operation. A linear mixed model was used to evaluate longitudinal changes and influences of each solution.

RESULTS

No primary failure was observed. At postoperative day 0, transaminase values were higher in the SCOT 15 than in the UW group: aspartate transaminase: 2,435 ± 399 vs 589 ± 83 IU/L (P < .01); alanine transaminase: ALT: 1,207 ± 191 vs 484 ± 64 IU/L (P < .05), then returned to low levels in both groups. From day 0 to 8, coagulation factors reached normal values; there was no difference between the 2 groups. Total bilirubin decreased similarly in the 2 groups. However, from the second postoperative week (W1) to W8, the SCOT 15 group showed a slow decrease in the mean values of gamma-glutamyltranspeptidase (gGT) from 233 ± 125 to 130 ± 161 IU/L, which were significantly lower than those in the UW group, where the gGT remained around 300 IU/L (P < .01). The End-Stage Liver Disease, Child-Pugh, or United Network for Organ Sharing scores, primary liver diseases, hepatitic C virus status, arterial or biliary complications, and male/female ratio, which was different in the 2 groups, did not statistically influence these results.

CONCLUSIONS

The main effect of cold storage of human liver using SCOT 15 compared with UW solution was to decrease cholestasis following transplantation.

Progression from isolated steatosis to steatohepatitis and fibrosis in nonalcoholic fatty liver disease

In patients with nonalcoholic fatty liver disease (NAFLD) isolated steatosis is considered a benign condition with no or minimal rate of progression, in contrast to nonalcoholic steatohepatitis (NASH) which can progress to cirrhosis. We report on a series of six patients with isolated steatosis on an initial liver biopsy, and NASH on a follow-up biopsy performed five years after. All but one of the initial biopsies were longer than 15 mm. At follow-up, inflammation and ballooning were present in all patients and mild fibrosis in three. All patients had one or more features of metabolic syndrome at baseline. Progression to steatohepatitis occurred independent of aminotransferase changes. Five patients experienced an increase in one or several metabolic risk factors during follow-up: body mass index, triglyceride levels, arterial hypertension and/or the HOMA index. One patient did not exhibit progression but was still exposed to metabolic risks factors at the end of follow-up. This report demonstrates that isolated steatosis is not necessarily a benign, non-progressive condition. Current recommendations for the absence of hepatic monitoring in patients with isolated steatosis are not adequate. If metabolic risk factors persist or deteriorate during follow-up and/or non-invasive markers suggest disease progression, a control liver biopsy should be considered.

Identification of CD8+CD25+Foxp3+ suppressive T cells in colorectal cancer tissue

BACKGROUND

The antitumoral immune response is one determinant of colorectal cancer (CRC) outcome. Recent work suggests that Foxp3(+)CD25(+)CD4(+) regulatory T cells (T4reg) might hamper effective immunosurveillance of emerging cancer cells and impede effective immune responses to established tumours. In this descriptive study, we analysed blood and tissue regulatory T cell populations in patients with CRC.

METHODS

Blood and tissue regulatory Foxp3(+) T cells from 40 patients with CRC were compared to regulatory Foxp3(+) T cells from normal colonic tissue and from blood of 26 healthy volunteers. Flow cytometry was used to quantify and phenotype all Foxp3(+) T cell populations. Correlations were sought with the tumour stage and with micro-invasive status. The suppressive capacity of regulatory Foxp3(+) T cells was assessed by their effect on CD4(+)CD25(-) T cell proliferation in vitro and by their capacity to inhibit cytokine production by conventional T cells.

RESULTS

We found a significant increase of CD8(+)CD25(+)Foxp3(+) cells (T8reg) in blood and CRC tissue; their phenotype was close to that of T4reg. T8reg cells infiltrating CRC were activated, as suggested by increased cytoxic T lymphocyte-associated antigen-4, glucocorticoid-induced tumour necrosis factor-related protein, and transforming growth factor (TGF)beta1 expression compared to T8reg from normal autologous colonic tissue. Moreover, T8reg were able to suppress CD4(+)CD25(-) T cell proliferation and Th1 cytokine production ex vivo, demonstrating that tumour-infiltrating T8reg have strong suppressive capacities. T8reg numbers correlated with the tumour stage and with micro-invasive status. Finally, interleukin 6 and TGF beta 1 synergistically induced the generation of CD8(+)CD25(+)Foxp3(+) T cells ex vivo.

CONCLUSIONS

We have identified a new regulatory T cell population (CD8(+)Foxp3(+)) in colorectal tumours. After isolation from cancer tissue these CD8(+)Foxp3(+) cells demonstrated strong immunosuppressive properties in vitro. These data suggest that these cells may contribute to tumoral immune escape and disease progression.

Histological progression of non-alcoholic fatty liver disease: a critical reassessment based on liver sampling variability

BACKGROUND

In non-alcoholic fatty liver disease, histological lesions display a significant sampling variability that is ignored when interpreting histological progression during natural history or therapeutic interventions.

AIM

To provide a method taking into account sampling variability when interpreting crude histological data, and to investigate how this alters the conclusions of available studies.

METHODS

Natural history studies detailing histological progression and therapeutic trials were compared with the results of a previously published sampling variability study.

RESULTS

Natural history studies showed an improvement in steatosis, which was significantly higher than expected from sampling variability (47% vs. 8%, P < 0.0001). In contrast, no study showed a change in activity grade or ballooning higher than that of sampling variability. There was only a marginal effect on fibrosis with no convincing demonstration of a worsening of fibrosis, a conclusion contrary to what individual studies have claimed. Some insulin sensitizing drugs and anti-obesity surgery significantly improved steatosis, while most did not significantly impact on fibrosis or activity.

CONCLUSIONS

Sampling variability of liver biopsy is an overlooked confounding factor that should be considered systematically when interpreting histological progression in patients with non-alcoholic fatty liver disease.

Diagnostic value of serum protein profiling by SELDI-TOF ProteinChip compared with a biochemical marker, FibroTest, for the diagnosis of advanced fibrosis in patients with chronic hepatitis C

BACKGROUND

FibroTest has been validated for the diagnosis of liver fibrosis in patients with chronic hepatitis C.

AIM

To compare FibroTest with a new proteome-based model for the prediction of advanced liver fibrosis.

METHODS

Sera from 191 consecutive patients with simultaneous liver biopsy and FibroTest on fresh sera were used for retrospective mass spectrometry analysis. A new fibrosis index was constructed combining proteomic peaks, selected on differential expression according to fibrosis stages in logistic regression analyses. The main end point was the diagnosis of advanced fibrosis on liver biopsy.

RESULTS

Eight out of 1000 peaks were selected for the construction of the proteomic index. The area under the receiver operating curve (AUROC) of the proteomic index was 0.88 (95% CI: 0.82-0.92), significantly greater than the FibroTest AUROC of 0.81 (95% CI: 0.74-0.86; P = 0.04); the AUROC of the proteomic and FibroTest combination was 0.88 (95% CI: 0.83-0.92). Seven of the eight selected peaks were highly associated with the FibroTest score, with different patterns of association with the five components of FibroTest.

CONCLUSIONS

A proteomic index combining eight peaks had an excellent accuracy value for the diagnosis of advanced fibrosis in patients with chronic hepatitis C. However, despite a statistical significance, the small improvement delivered by proteomics impairs clinical applications because of its cost and its variability compared with the well validated FibroTest.

Variability of the area under the receiver operating characteristic curves in the diagnostic evaluation of liver fibrosis markers: impact of biopsy length and fragmentation

BACKGROUND

The area under the receiver operating characteristic (ROC) curve is widely used as an estimate of the diagnostic value for fibrosis markers. Biopsy length and fragmentation are known as risk factors of false positive or false negative of biopsy but their quantitative impact on area under the receiver operating characteristic curve variability has not been assessed.

AIM

To assess these relationships to better compare the fibrosis markers.

METHODS

The area under the ROC curves of FibroTest for the diagnosis of fibrosis was estimated in patients with chronic hepatitis C using an integrated database including 1312 patients with FibroTest and biopsy. To take into account the biopsy length, we used two adjustment factors: one in which an observed area under the ROC curve could be adjusted according to the relative area under the receiver operating characteristic curve of a biopsy of a given length vs. the entire liver and one taking into account the prevalence of each fibrosis stage defining advanced and non-advanced fibrosis.

RESULTS

The mean biopsy length was smaller for cirrhosis (F4, 16 mm) vs. F3, (18 mm, P=0.01) and F0 (19 mm, P=0.01). The mean number of fragments was higher for cirrhosis (F4=4.1 fragments) vs. all the other stages (F0=1.9, F1=1.9, F2=1.9, F3=2.3; P<0.001 vs. F4). The FibroTest area under the ROC curves for the diagnosis of advanced fibrosis, adjusted for stages' prevalence, ranged from 0.80 to 0.98 depending on biopsy length and fragmentation, respectively.

CONCLUSION

The comparison of the area under the ROC curves of fibrosis markers should take into account the biopsy length and fragmentation.