Immune-mediated Gastritis in a Patient with metastatic Lung Cancer due to Therapy with the immune Checkpoint Inhibitor Pembrolizumab - Differences and Similarities in Comparison to "endogenous" autoimmune Type A Gastritis and a review of literature

Immune checkpoint inhibitors are increasingly used in advanced malignant diseases and are well-known for their good results. With the blockade of immune checkpoints, the probability of immune-related adverse events is also increased.We present a 54-year-old female patient with advanced NSCLC. She was treated with pembrolizumab and developed a stable disease under therapy. After six cycles, she presented with massive epigastric pain to our emergency department. Gastroscopy showed severe erosive-fibrinous pangastritis without the involvement of the esophagus, duodenum, or other immune-related adverse effects. Histology showed the complete destruction of the gastric mucosa. We concluded an immune-mediated gastritis by pembrolizumab, after the exclusion of other differential diagnoses.Despite treatment with prednisolone and marked improvement of her symptoms, the mucosa was never fully reconstituted into a healthy mucosa.Furthermore, we collected published reports of similar cases and conducted a comparison with features of a typical, endogenous type A gastritis to highlight similarities and differences.

Candesartan-Induced Enteropathy That Mimics Celiac Disease in a 90-Year-Old Patient

Sprue-like enteropathy (SLE) is a clinical syndrome similar to celiac disease and has been associated with the use of various angiotensin receptor blockers (ARBs), a class of medications frequently used in the management of hypertension. Currently, there has only been one documented case report which has observed this occurrence with the use of the ARB candesartan. A 90-year-old female patient presented with chronic diarrhea and weight loss of unclear etiology. Diagnostic esophagogastroduodenoscopy and ileocolonoscopy were macroscopically unremarkable, but histological samples revealed complete villous atrophy, chronic mucosal inflammation, and intraepithelial T-lymphocytic infiltration. However, serological studies could not confirm celiac disease as a cause for the patient’s symptoms of malabsorption. After exclusion of other intestinal inflammation etiologies with noted ongoing candesartan use, the diagnosis of SLE was made, and candesartan therapy was discontinued. Additionally, we decided to initiate a lactose-free diet. Clinical remission was achieved without any recurrences. Candesartan is a commonly prescribed therapeutic agent in the treatment of hypertension. Our case underlines the importance of considering it as a potential cause for unexplained symptoms of malabsorption.

The diagnostic challenge of abdominal tuberculosis in nonendemic countries: A case series from a tertiary hospital in Germany

Abdominal tuberculosis is a rare clinical condition in nonendemic countries and should be included as differential diagnosis by unspecific abdominal complaints, especially in patients with immigration background from high-prevalence regions.

Expression pattern of cell cycle-related gene products in synovial stroma and synovial lining in active and quiescent stages of rheumatoid arthritis

OBJECTIVE

To investigate the expression pattern of cell cycle related gene products in active and quiescent Rheumatoid arthritis (RA).

METHODS

Synovial tissue from 20 patients with active proliferative RA and 28 patients with RA in remission was immunohistochemically examined for expression of p53, p63, p21, p27, p16, cyclin D1, CDK4, RB, E2F, Ki-67 on tissue microarrays and by DNA flow cytometry for cell cycle phases.

RESULTS

Elevated expression of p53 and p27 was found in synovial lining and in stromal cells in proliferative active RA. In the remission stage this finding was confined to the synovial lining. Most of the cells were in the G0-phase. Ki-67 proliferation index was maximum 10% in synovial cells.

CONCLUSION

The p53 pathway is activated in synovial cells in active RA as well as in quiescent stage of disease. Differences in the spatial expression pattern of proteins involved in the p53 pathway in RA in remission compared to actively proliferating RA reflect the phasic nature of the disease and support in our opinion the concept of adaptive role of p53 pathway in RA.

Strong expression of Bcl-2 in pigmented villonodular synovitis of the knee with aggressive clinical behaviour

OBJECTIVE

To determine the expression of bcl-2, p53, and caspase 3, and measure the Ki-67 proliferation index as well as DNA content and DNA fragmentation in a case of diffuse pigmented villonodular synovitis (PVNS) of the knee with aggressive clinical behaviour.

METHODS

Expression of p53, Bcl-2 and Ki-67 was investigated using immunohistochemistry. In addition, multiparametric flow cytometry was performed for expression of p53, bcl-2, and caspase 3, as well as analysis of DNA content and distribution of cell cycle phases. DNA fragmentation was detected by the terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick end labelling (TUNEL).

RESULTS

A strong cytoplasmic positivity for Bcl-2 protein, a key factor in regulation of apoptosis, was found in the majority of proliferating synovial cells. No apoptotic cell fraction was found by analysis of DNA content. DNA fragmentation was observed in 6.8% of cells. No elevated expression of p53 and caspase 3 was detected.

CONCLUSION

Our results indicate a possible role of dysregulation of apoptosis in this case of PVNS. This aspect in the pathogenesis of PVNS should be clarified in further studies.

Rheumatoid arthritis and pigmented villonodular synovitis: comparative analysis of cell polyploidy, cell cycle phases and expression of macrophage and fibroblast markers in proliferating synovial cells

AIMS

Rheumatoid arthritis (RA) and pigmented villonodular synovitis (PVNS) are aggressive diseases with progressive joint destruction. The present study aims to define cell cycle phases, polyploidy and the immunophenotype of proliferating synovial cells in both diseases.

METHODS AND RESULTS

Synovial tissues from patients with proliferative-active RA, localized and diffuse PVNS were analysed by DNA flow cytometry, immunohistochemistry and double immunofluorescence with confocal laser scan microscopy. Expression of macrophage markers (CD68/CD163), fibroblast markers (h4Ph/CD55) and Ki67 antigen was examined. Synovial cells positive for either macrophage or fibroblast markers as well as double-labelled cells were found in both RA and PVNS. In RA, CD68/CD163+ synoviocytes were preferentially located in the vicinity of the synovial lining layer, while they were more randomly distributed in PVNS. Of cases with diffuse PVNS, 20% showed an aneuploid cell pattern. All samples of localized PVNS and RA were diploid. Proliferative activity was significantly higher in aneuploid PVNS.

CONCLUSIONS

In spite of their histologically homogeneous appearance, proliferating synovial cells display a heterogeneous immunophenotype in both RA and PVNS, indicating functional properties of both macrophages and fibroblasts. Aneuploidy seems to be a special feature of diffuse PVNS.

Analysis of chromosomal imbalances by comparative genomic hybridisation of pigmented villonodular synovitis

Using comparative genomic hybridisation, DNA copy number changes were investigated in 15 cases of pigmented villonodular synovitis of the knee joint. Additionally DNA content was analysed by flow cytometry. Screening revealed numerical chromosomal imbalances in five of the examined cases. A total number of 18 gains were detected. The most frequent gains involved subregions of chromosomal arms 22q and 16p and 16q. No losses were found. One of the cases showed an aneuploid DNA-pattern, which actually proved to be the case with the most numerical chromosomal changes.

Apoptosis resistance in pigmented villonodular synovitis

OBJECTIVE

Pigmented villonodular synovitis (PVNS) is a proliferative lesion originating from synovial tissue with a locally aggressive behaviour. We analysed the pathogenetic role of apoptosis resistance for sustained cell proliferation in PVNS.

METHODS

The expression of bcl-2, p53 and Ki-67 was examined in 80 cases of PVNS using immunohistochemistry. In 43 of these cases, DNA content and distribution of cell-cycle phases were investigated by flow cytometry. Additionally, 10 cases of PVNS were analysed by multi-parametric flow cytometry for expression of p53, caspase3, and bcl-2 and by TUNEL to detect DNA fragmentation.

RESULTS

No apoptotic cell fractions were detected in any investigated cases. Expression of bcl-2 was found in 84% of cases (up to 6.5% of cells) and was significantly associated with DNA-fragmentation observed by TUNEL (p=0.037). Orthologous p53 expression was observed in 37% of cases. The level of p53 expression correlated with the proliferative activity and the expression of both caspase3 (p=0.017) and bcl-2 (p=0.0013). (No statistically significant correlations between expression of bcl-2, p53, caspase3, DNA fragmentation or proliferative index and age, sex of patients, disease recurrence, growth pattern or size of lesion were found).

CONCLUSION

Apoptosis resistance is a critical event in the progression of PVNS and may contribute to the survival of the proliferating synovial cells in PVNS and to the permanent slow progression of these lesions.

Expression of cell cycle-related gene products in different forms of primary versus recurrent PVNS

Expression patterns of cell cycle regulating gene products and Ki-67 in proliferating synovial cells of primary and recurrent pigmented villonodular synovitis (PVNS) in localized and diffuse lesions were examined by immunohistochemistry. Alterations of cell cycle-related proteins were seen in 98.7% of analyzed lesions. Both RB- and p53 pathways play a role in cell cycle dysregulation in PVNS. The RB pathway was more frequently altered in primary disease, while alterations of the p53 pathway seemed to be more important in recurrent lesions, regardless of the histomorphological type of disease. Ki-67 proliferation rate was elevated in recurrent tumors.

Comparative analysis of cell populations involved in the proliferative and inflammatory processes in diffuse and localised pigmented villonodular synovitis

The aim of the present study was a comparative quantitative evaluation of cell populations involved in the proliferative and inflammatory compartment in both localised and diffuse pigmented synovitis villonodularis (PVNS). 15 cases of each localised and diffuse PVNS were examined by flow cytometry, immunohistochemistry, double immuno-fluorescence and confocal microscopy with quantitative evaluation of CD3-, CD4-, CD8-, CD20-, CD57-, CD55-, CD68-, CD163- and h4Ph positive (+) cells. The proliferative compartment of localised and diffuse PVNS was mainly composed of double-positive CD68+/h4Ph+ (CD163+/CD55+) synoviocytes. The number of double-positive synoviocytes for macrophage and fibroblast markers was significantly higher in diffuse compared to localised PVNS. The accompanying inflammatory infiltrate showed a predominance of cytotoxic cells (CD8+, CD57+), whereby the number of CD3+ and CD20+ cells was significantly higher in localised PVNS. The number of CD57+ NK cells was significantly higher in diffuse PVNS. The proliferating macrophage- like synovial cells and the cytotoxic lymphocytes could contribute to the aggressive behaviour of localised and diffuse PVNS. Moreover, with regard to the quantitative differences in cell composition between diffuse and localised PVNS and their different clinical behaviour, further studies should continue to analyse localised and diffuse PVNS separately.

Detection of hematogenic and lymphogenic tumor cell dissemination in patients with medullary thyroid carcinoma by cytokeratin 20 and preprogastrin-releasing peptide RT-PCR

Despite an extensive surgical approach only 50% of the patients with medullary thyroid carcinoma (MTC) are biochemically cured. The failure to cure a larger number of patients is a result of the early dissemination of MTC. The present study evaluates two RT-PCR based assays for the detection of disseminated tumor cells in blood, bone marrow and lymph node samples of patients with MTC. Frozen tissue and blood samples of 19 patients with MTC and 61 cervical lymph nodes of these patients were obtained intraoperatively during thyroidectomy and lymphadenectomy. Preoperative bone marrow samples were obtained from 8 patients with MTC. An expression of CK20 and preproGRP was found in all MTC tissue samples. Using CK20-PCR, disseminated MTC cells were detected in 67% of the cervical lymph nodes of patients with MTC, compared to 72% involved lymph nodes, detected by preproGRP-PCR. In 16 of 61 nodes (26%) each PCR-system detected disseminated tumor cells in histologically tumor-free lymph nodes. Disseminated tumor cells were detected with CK20-PCR and preproGRP in 5 of 18 (28%) preoperative blood samples, each. The detection of a hematogenic tumor cell dissemination by preproGRP correlated significantly with the tumor stages (p = 0.019). Circulating MTC cells were found in 3 of 8 bone marrow samples with CK20-PCR, compared to 1 of 8 samples with preproGRP-PCR. Both PCR assays are highly sensitive to detect disseminated MTC cells in blood, bone marrow and lymph node samples. Our results of disseminated MTC cells in 26% of histologically tumor-free cervical lymph nodes and in 28% of the blood samples of patients with MTC might therefore explain the low biochemical cure rates.

Cytokine/chemokine messenger-RNA expression profiles in ulcerative colitis and Crohn's disease

To define mediator profiles in inflamed and noninflamed areas in inflammatory bowel disease (IBD) we analyzed the expression of 35 messenger-RNAs (mRNAs) encoding cytokines, chemokines, and some related molecules in transmural gut tissues (n=138) from patients with ulcerative colitis (UC), Crohn's disease (CD), and inflammatory and normal controls by real-time quantitative reverse transcription polymerase chain reaction. Using sample collectives with a comparable degree of inflammation, most parameters investigated showed similarly increased mRNA expression levels in both active UC and CD. This included proinflammatory cytokines, but also interferon (IFN) gamma and several IFN-gamma inducible chemokines. Only macrophage inflammatory protein (MIP)-2alpha mRNA was expressed at higher levels in inflamed UC vs. CD. IH revealed that MIP-2alpha protein was produced mainly by intestinal epithelial cells. Importantly, in histologically noninflamed/inactive IBD samples mRNAs for several mediators were significantly enhanced, accompanied by elevated levels of migration-inhibition factor related protein (MRP) 14 transcripts. CD14 positive macrophages were found especially in noninflamed/inactive UC, many of which coexpressed the RFD-7 antigen. Our results indicate a substantial overlap in cytokine/chemokine mRNA expression in UC and CD. Elevated mediator expression is evident in noninflamed/inactive areas in both diseases. Local recruitment of MRP-14 positive leukocytes might contribute to this phenomenon. In inactive UC a phenotypically altered population of macrophages expressing CD14 might play an additional role.

Detection of disseminated medullary thyroid carcinoma cells in cervical lymph nodes by cytokeratin 20 reverse transcription-polymerase chain reaction

Local recurrence in differentiated and medullary thyroid carcinoma develops frequently from metastatic infiltration of cervical lymph nodes. Despite an aggressive surgical approach, postoperative calcitonin levels as biochemical evidence for residual cancer cells remain often elevated in patients with medullary thyroid carcinoma. In the present study, we compared the detection rates of disseminated medullary thyroid carcinoma cells in cervical lymph nodes by histopathology with reverse transcription-polymerase chain reaction (RT-PCR) amplification of cytokeratin 20 (CK20) transcripts as a more sensitive but still specific molecular parameter for residual thyroid cancer cells. Forty-two cervical lymph nodes obtained from 7 patients with CK20positive medullary thyroid carcinomas were cut into two halves, one used for conventional histology, the other subjected to RNA extraction and subsequent amplification of cytokeratin 20 transcripts. Matching results for CK20 RT-PCR and histopathology were found in 74% (31/42)of the examined lymph nodes (52% positive results, 48% negative results). Positive CK20 RT-PCR pointed to residual thyroid carcinoma cells in another 19% (8/42), in which no thyroid carcinoma cells were identified by histopathology. Histology and immunohistochemistry,however, identified tumor cells in 7% (3/42) of the analyzed lymph nodes, from which no CK20 transcript could be amplified (false-negative results). These data suggest that CK20 RT-PCR might be more sensitive to detect nodal involvement of CK20 positive medullary thyroid carcinomas than conventional histopathology. In combination with histology, it might help to identify patients with residual disease after surgery.