Bcor Immunohistochemistry, And Not SATB2, Is A Sensitive And Specific Diagnostic Biomarker For Cns Tumors With BCOR Internal Tandem Duplication

Central nervous system (CNS) tumors with the BCOR (BCL6 Corepressor) internal tandem duplication (ITD) were recently isolated by a DNA-methylation profile from a series of primitive neuroectodermal tumors [1]. They are mainly characterized by a recurrent BCOR ITD and express BCOR by immunohistochemistry (IHC) [2]. In rare cases, they present an EP300-BCOR fusion inducing the absence of expression of BCOR by IHC [3]. In soft tissue and kidney tumors with different types of BCOR alterations, SATB2 has been considered a diagnostic hallmark and BCOR IHC is not highly specific in some other contexts (soft tissue and uterine tumors) [4]. In a recent paper, SATB2 immunoexpression has been evidenced in one CNS-tumor with proven BCOR ITD [5]. The aim of our study was to evaluate the sensitivity and specificity of the BCOR and SATB2 immunostainings in a large cohort of pediatric CNS tumors.

Increased frequency of detection of human papillomavirus deoxyribonucleic acid in exfoliated cervical cells during pregnancy

Exfoliated cells of the uterine cervix obtained from women during pregnancy and at the time of their first postpartum examination were used to monitor the prevalence of human papillomavirus infections in this population and to study the natural fluctuations in viral expression. When deoxyribonucleic acid hybridization analysis alone was used to monitor the presence of human papillomavirus infection, 20.9% of our study population had results that were positive for human papillomavirus deoxyribonucleic acid during their first-trimester examinations. A dramatic increase in the percentage of women with positive results for human papillomavirus deoxyribonucleic acid was observed at the time of the patients' third-trimester examinations (46%). The overall increase in human papillomavirus-positive patients was a combination of a small number of patients who had positive results on their first examination and negative results on their second examination, and a larger number of patients who had negative results on their first-trimester examination and positive results for human papillomavirus deoxyribonucleic acid in the exfoliated cervical cells at the time of their third-trimester examination. The total percentage of patients with positive results for human papillomavirus deoxyribonucleic acid in their cervical cells at one or both assay points during pregnancy was 52.5%. Samples obtained at the postpartum examination demonstrated a dramatic decrease in the number of samples positive for human papillomavirus deoxyribonucleic acid (17.5%). This result was a combination of a large decrease in human papillomavirus-positive patients coupled with a small increase in detectable levels of human papillomavirus deoxyribonucleic acid in cervical samples from patients who had negative results on their previous examination. This study demonstrates a very high level of detectable human papillomavirus deoxyribonucleic acid in exfoliated cervical cells obtained during pregnancy and shows that the detectable levels of human papillomavirus deoxyribonucleic acid fluctuate during pregnancy.

Mechanism for human papillomavirus transmission at birth

We attempted to investigate mechanisms, in addition to sexual contact, by which human papillomaviruses associated with anogenital tract lesions could be transmitted. Samples of exfoliated cervical cells were obtained from 45 pregnant women and were assayed by Southern blot hybridization analysis for the presence of human papillomavirus nucleic acids. Twenty-five of the 45 women had cells positive for human papillomavirus deoxyribonucleic acid. A neonatal nasopharyngeal aspirate was obtained at term and analyzed for the presence of human papillomavirus deoxyribonucleic acid. We documented the presence of human papillomavirus deoxyribonucleic acid in the oral pharyngeal cavity of the neonates in 15 of 45 nasopharyngeal samples analyzed. Amniotic fluid was obtained from 13 patients when their membranes were artificially ruptured. These samples were assayed for the presence of human papillomavirus deoxyribonucleic acid; two of the 13 amniotic fluid samples contained human papillomavirus deoxyribonucleic acid. The detection of human papillomavirus deoxyribonucleic acid in the oral cavity of neonates is indicative of a perinatal mechanism of viral transmission. The detection of human papillomavirus deoxyribonucleic acid in the amniotic fluid may suggest an in utero mechanism of transmission. However, problems encountered in collecting the amniotic fluid samples preclude us from definitive interpretation of these data.