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1

artículo

Detection of Helicobacter pylori in gastric cancer tissue through histopathology, immunohistochemistry and real-time reverse transcription-PCR

Publicado por
A Castaneda C., Castillo M., Sanchez J., Casavilca S., A Bernabe L., Suarez N., Chavez I., Ruiz E., Tello K., R Villa M., Zevallos R., Montenegro P., Dias-Neto E., Landa-Baella M., Taxa L.

Publicado 2020

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Aim: Helicobacter pylori is usually detected based on hematoxylin-eosin (H-E) features, but, immunohistochemistry (IHC) and real-time PCR (RT-PCR) are more precise in chronic-gastritis. We evaluated the relevance of these tests in Peruvian gastric cancer samples. Materials & methods: We performed and evaluated H-E, IHC staining and RT-PCR in 288 gastric tumors. Slides were independently evaluated by three pathologists. Results: H. pylori was detected in 167/287 through H-E, 140/288 through IHC and 175/288 through RT-PCR, and positive-status were associated (p < 0.001). H. pylori detection by H-E had a good concordance with IHC (kappa index = 0.632) but poor with RT-PCR (kappa index = 0.317). Higher median gene-copies were found in high H. pylori density through H-E or IHC (p < 0.001). Conclusion: H-E evaluation is accurate in gastric cancer, and IHC and RT-PCR can complement its results....

2

artículo

Prevalence of helicobacter pylori infection, its virulent genotypes, and Epstein-Barr virus in peruvian patients with chronic gastritis and gastric cancer

Publicado por
Castaneda C.A., Castillo M., Chavez I., Barreda F., Suarez N., Nieves J., Bernabe L.A., Valdivia D., Ruiz E., Dias-Neto E., Landa-Baella M.P., Bazan Y., Rengifo C.A., Montenegro P.

Publicado 2019

Enlace

PURPOSE Helicobacter pylori (HP) and Epstein Barr virus (EBV) infections induce chronic gastritis (CG) and are accepted carcinogenics of gastric cancer (GC). Our objective for this study was to determine the prevalence of these agents and clinicopathological features of GC and CG associated with the infection. PATIENTS AND METHODS A single-center cohort of 375 Peruvian patients with GC and 165 control subjects with CG were analyzed. Evaluation of HP and EBV genes was performed through quantitative polymerase chain reaction. RESULTS Prevalence of HP was 62.9% in the whole population and 60.8% in the GC subset. The cagA gene was detected in 79.9%; vacAs1 and vacAm1 alleles in 41.6% and 60.7%, respectively; and concurrent expression of vacAs1 and vacAm1 in 30.4% of infected patients in the whole series. The prevalence of EBV was 14.1% in the whole population and was higher in GC (P , .001)....

3

artículo

Level of tumor-infiltrating lymphocytes and density of infiltrating immune cells in different malignancies

Publicado por
Castaneda C.A., Castillo M., Aliaga K., Bernabe L.A., Casavilca S., Sanchez J., Torres-Cabala C.A., Gomez H.L., Mas L., Dunstan J., Cotrina J.M., Abugattas J., Chavez I., Ruiz E., Montenegro P., Rojas V., Orrego E., Galvez-Nino M., Felix B., Landa-Baella M.P., Vidaurre T., Villa M.R., Zevallos R., Taxa L., Guerra H.

Publicado 2019

Enlace

Aim: To correlate levels of tumor-infiltrating lymphocytes (TIL) evaluated using the International Immuno-Oncology Biomarker Working Group methodology, and both density of tumor-infiltrating immune cell and clinicopathological features in different malignancies. Methods: 209 pathological samples from gastric cancer, cervical cancer (CC), non-small-lung cancer, cutaneous melanoma (CM) and glioblastoma were tested for TIL in hematoxylin eosin, and density of CD3+, CD4+, CD8+, CD20+, CD68+ and CD163+ cells by digital analysis. Results: TIL levels were higher in invasive margin compartments (IMC). TIL in IMC, intratumoral and stromal compartments predicted survival. CC and gastric cancer had higher TIL in intratumoral; CC and CM had higher TIL in stromal compartment and IMC. CM had the highest density of lymphocyte and macrophage populations. CD20 density was associated with survival in the ...