A Rare Case Of CNS High-Grade Neuroepithelial Tumor With BCOR Alteration (HGNET-BCOR)

Introduction/Objective

HGNET-BCOR is a distinct molecular CNS tumor entity that was first identified by DNA methylation analysis in 2016. It is defined by an in-frame internal tandem duplication in exon 15 of the BCOR gene.

The BCOR mutation is not unique to this tumor entity and can be seen in other CNS tumors, as well as solid organ and hematologic malignancies. In this report, we describe the pathology in a 2-year-old girl with a posterior fossa brain tumor initially diagnosed as high-grade neuropeithelial tumor at an outside facility.

Methods

She underwent resection and adjuvant chemotherapy at the same institution. She presented later to our hospital complaining of fatigue and vomiting, and tumor recurrence on MRI. Microscopic examination of the recurrent tumor showed a relatively circumscribed lesion with atrophic cerebellar folia associated with some of the tumor fragments. Tumor cells were arranged in papillary, pseudopapillary, and rosetted patterns in a myxoid (Alcian-blue positive) background. The tumor showed regional necrosis and frequent mitoses (mitotic index ~14–15 /10 HPFs). An extensive panel of immunostains was performed.

Results

The tumor was diffusely and strongly positive only for vimentin and EGFR, with diffuse moderate staining for BCL-2, and patchy weak staining for S100 protein. There were rare, focal tumor cells with GFAP and neurofilament staining. The Ki67 labeling index was 80–90%. All other tested markers were negative. The primary tumor resection was later found to be positive for BCOR by IHC. Sequencing for exon 15 of the BCOR gene showed an in-frame internal tandem duplication.

Conclusion

These features are consistent with the diagnosis of HGNET-BCOR. The pathologic and clinical features for this rare tumor entity are not widely known. Further studies with additional patients are needed to expand our understanding of these rare tumors to develop new treatment approaches.

First line fertility treatment strategies regarding IUI and IVF require clinical evidence

The advent of intracytoplasmic sperm injection (ICSI) has contributed to a significant growth in the delivery of assisted conception technique, such that IVF/ICSI procedures are now recommended over other interventions. Even the UK National Institute for Health Care Excellence (NICE) guidelines controversially recommends against intrauterine insemination (IUI) procedures in favour of IVF. We reflect on some of the clinical, economic, financial and ethical realities that have been used to selectively promote IVF over IUI, which is less intrusive and more patient friendly, obviates the need for embryo storage and has a global application. The evidence strongly favours IUI over IVF in selected couples and national funding strategies should include IUI treatment options. IUI, practised optimally as a first line treatment in up to six cycles, would also ease the pressures on public funds to allow the provision of up to three IVF cycles for couple who need it. Fertility clinics should also strive towards ISO15189 accreditation standards for basic semen diagnosis for male infertility used to triage ICSI treatment, to reduce the over-diagnosis of severe male factor infertility. Importantly, there is a need to develop global guidelines on inclusion policies for IVF/ICSI procedures. These suggestions are an ethically sound basis for constructing the provision of publicly funded fertility treatments.

Myxopapillary ependymoma: correlation of clinical and imaging features with surgical resectability in a series with long-term follow-up

STUDY DESIGN

Retrospective case series.

OBJECTIVES

The objective of this study is to identify imaging and intraoperative characteristics that may predict surgical resection for myxopapillary ependymoma (MPE). The diffuse involvement in the conus-filum region makes complete resection challenging. The preoperative characteristics that may estimate the extent of resection has not been reported.

SETTING

Toronto, Canada.

METHODS

All MPE cases between 1972 and 2005 at a single institution were identified and reexamined by a neuropathologist. Neurological outcomes (Frankel scale), clinical features, operative findings, pre and postoperative imaging results were reviewed.

RESULTS

A total of 18 operations were performed on 15 MPE patients (8 females/7 males; age range: 18-71 years). Median postoperative follow-up was 56 months. Three patients (17%) developed tumor regrowth requiring reoperations. Preoperative magnetic resonance imaging (MRI; in 14/18 procedures) determined that tumors involved the conus in 70% of cases, which was significantly associated with intraoperative findings (P=0.02). Complete microsurgical resection was accomplished in 4 out of 7 cases where conus was not involved, but in only 1 out of 10 cases with conus involvement (P=0.056). The degree of conus involvement in one case was unclear. None of patients with total surgical resection developed recurrence. All patients survived at long-term follow-up.

CONCLUSION

Our series is the first to correlate MPE involvement to conus medullaris on preoperative MRI with intraoperative findings, and examine its significance on surgical resectability. This information could guide clinicians in preoperative planning and advising patients on treatment options and potential risks/benefits. MRI is very sensitive (100%) and moderately specific (67%) in detecting direct anatomical contact between conus and MPE tumors.

Intracerebral rhabdoid and papillary meningioma with leptomeningeal spread and rapid clinical progression

OBJECTIVE AND IMPORTANCE

Rhabdoid meningioma (RM) is a relatively new, Grade III tumor entity according to the latest WHO classification. We report rhabdoid and partly papillary, highly anaplastic, intracerebral meningioma with diffuse leptomeningeal spread and distant SCF metastasis to the cervical cord.

CLINICAL PRESENTATION

This 27-year-old female was admitted to the hospital with radiological findings suggestive of a primary brain tumor or a metastasis. After subtotal resection and during radiotherapy, follow-up MRI revealed recurrence, metastasis to meninges at the high cervical level, and diffuse basal leptomeningeal enhancement indicating infiltrating tumor. She died approximately 3 months after onset of symptoms.

RESULTS

Histological examination revealed rhabdoid and papillary meningioma with high proliferation rate (80% of MIB1-positive cells), necrosis and extensive brain invasion. It was positive for vimentin and S-100 protein, showed focal epithelial membrane antigen expression and accumulation of intermediate filaments on ultrastructural examination. The recurrent tumor diffusely infiltrated leptomeninges and subarachnoid space.

CONCLUSION

This is a rare example of mixed, rhabdoid and papillary variant of meningioma, located entirely within the brain parenchyma and accompanied by a fulminant clinical course. The combination of the histological anaplasia with the highest reported proliferation rate, and loss of the cohesion of neoplastic cells led to diffused infiltration of the leptomeninges and metastasis to the spinal cord.

A randomized, controlled trial comparing effect of oral misoprostol and intravenous syntocinon on intra-operative blood loss during cesarean section

BACKGROUND

Oxytocics are routinely used in an attempt to prevent excessive blood loss during cesarean section. Misoprostol, a potent uterotonic agent, has been reported to be useful in the prevention and treatment of postpartum hemorrhage by several investigators but its use during cesarean section has not been described. The objective of this study was to randomly compare the effectiveness of oral misoprostol with intravenous syntocinon on blood loss during elective cesarean sections under regional anesthesia.

METHODS

Sixty pregnant women were randomized either to receive misoprostol 400 micrograms orally or syntocinon 10 IU intravenously during cesarean section. The primary outcome measure was intra-operative blood loss as estimated by physicians, and by values of preoperative and postoperative hemoglobin concentration and hematocrit. Demographic characteristics of the subjects and outcomes were compared using chi-square test for categorical and two-sample t-test for continuous data.

RESULTS

Baseline characteristics in terms of age, body weight, parity, gestational age and indications for cesarean section were similar in both groups. The estimated blood loss was 545 ml (CI 476-614) in misoprostol group and 533 ml (CI 427-639) in syntocinon group (p = 0.85). Differences in preoperative and postoperative hemoglobin and hematocrit values were also similar in both groups. Two women in the misoprostol group and three in the syntocinon group (p=0.64) required additional oxytocics. One patient in each group required blood transfusion. No serious side effects were noted in either group.

CONCLUSION

Oral misoprostol appears to be safe and as effective as intravenous syntocinon in reduction of intra-operative blood loss during elective cesarean section under regional anesthesia and merits further investigation.

Natural history of fetal hydronephrosis diagnosed on mid-trimester ultrasound

OBJECTIVES

Renal tract dilatation is a common finding in routine prenatal ultrasound. However, there is no consensus as to the criteria used for differentiating pathological from physiological dilatation. The aim of this study was to evaluate the natural history and postnatal outcome of fetal hydronephrosis in an unselected obstetric population.

DESIGN

This was a prospective study of fetal hydronephrosis, detected at 18-23 weeks' gestation, in a routine obstetric population. Fetal hydronephrosis was diagnosed as 'mild' if the antero-posterior renal pelvic diameter (APRPD) measured >or = 4 mm and as 'moderate/severe' if the APRPD measured > or = 7 mm or if there was associated calyceal dilatation. The postnatal outcome of fetuses with persistent hydronephrosis (> or = 10 mm in the third trimester) was determined from a postal questionnaire.

RESULTS

During the study period, 11 465 women underwent an anomaly scan at 18-23 weeks of gestation. Fetal hydronephrosis was identified in 2.3% (268/11 465) of women. Mild hydronephrosis was present in 80.6% (216/268) and moderate/severe hydronephrosis in 19.4% (52/268). The hydronephrosis resolved in the antenatal or early neonatal period in 88% of fetuses. None of the fetuses with mild hydronephrosis and approximately one in three fetuses with persistent moderate/severe hydronephrosis required postnatal surgery. Overall, only one in every 1000 total births in the study population required postnatal urological surgery.

CONCLUSIONS

The current study highlights the natural history of antenatally detected hydronephrosis. Mild fetal hydronephrosis appears to be associated with an excellent prognosis and probably represents the group with physiological renal pelvic dilatation. Moderate/severe fetal hydronephrosis is associated with poorer outcome and is perhaps the group that will need more intense follow up both antenatally and postnatally.

Inhibition properties of Sepharose-bound trypsin and a protease on the surface of Ehrlich ascites tumour cells

Ehrlich ascites cells have been shown to possess a protease with beta-naphthylamidase activity located on the surface of these cells. This enzyme is protected from the inhibitory action of protein inhibitors of trypsin (EC 3.4.21.4) in free solution, but is inhibited by high concentrations of active site-directed inhibitors of trypsin. We believe the protection against inhibition is provided by the location of this protease on the cell surface. We employed a model system of trypsin coupled to Sepharose to demonstrate the protective action of an inert surface, resulting in a marked reduction in inhibition of trypsin-Sepharose, compared to trypsin in free solution, when exposed to both high and low molecular weight inhibitors. This cell protease has been shown to play a role in activation of the zymogen of collagenase exported by tumour cells. This role may have important implications for tumour cell invasion of the intercellular matrix.

A trypsin-like neutral protease on Ehrlich ascites cell surfaces: its role in the activation of tumour-cell zymogen of collagenase

Ehrlich ascites cells in mice have been shown to have a cell-surface trypsin-like neutral protease (TLNP) with proteolytic and beta-naphthylamidase activity. This activity is inhibited by low-mol.-wt inhibitors of trypsin but not by 11 high-mol.-wt inhibitors of trypsin in free solution. We believe that lack of inhibition is due to protection given to the enzyme by the chemical environment of the cell surface. These cells were demonstrated to export a collagenase zymogen which has been shown to be activated by the cell-surface TLNP. When this protease was completely inhibited by low-mol.-wt inhibitors of trypsin, chymotrypsin was used to activate the collagenase zymogen exported by Ehrlich ascites cells. Examination of the products of collagenolysis at 15 degrees C demonstrated the expected 3/4- and 1/4-length alpha-chain fragments derived from monomeric collagen, confirming that collagenase was one of the enzymes responsible for lysis of the collagen fibrils in the test system.

Biphasic kinetics of metal ion reactivation of trypsin-thiol complexes

This report describes biphasic kinetic data obtained when trypsin was inhibited by a thiol-containing inhibitor present in Ehrlich ascites tumour cells and then subjected to addition of Hg2+, Cu2+ or Ag+. This resulted in an initial re-activation of the trypsin, followed by inhibition of the enzyme with the addition of higher concentrations of these ions. The significance of these observations is 2-fold: (i) help to elucidate the mechanism of metal ion activation of latent enzymes, and (ii) also indicate that, in certain circumstances, the concentration of added metal ion determines whether the metal acts as an activator or an inhibitor of enzyme activity.

Inhibition of trypsin and chymotrypsin by thiols. Biphasic kinetics of reactivation and inhibition induced by sodium periodate addition

Biphasic kinetic data were obtained when trypsin (EC 3.4.21.4) which had previously been complexed with a thiol-containing inhibitor (present in Ehrlich ascites tumour cells) was incubated with incremental additions of periodate. At low concentrations of periodate the trypsin was re-activated whilst at higher concentrations of periodate the trypsin was irreversibly inhibited. This biphasic reactivation followed by inhibition was also demonstrated when trypsin was first inhibited by dithiothreitol and followed by incremental addition of periodate. Similar results were obtained with chymotrypsin (EC 3.4.21.1). Incremental additions of either dithiothreitol or periodate caused inhibition of both these enzymes. The biphasic kinetic data can be explained in terms of reduction and oxidation of a significant disulphide bond in both trypsin and chymotrypsin which can be cleaved by thiols in a disulphide exchange reaction [1]. This bond is thought to maintain the active centres of each of these enzymes in a conformation sterically favourable for enzymic cleavage of specific peptide bonds in the protein substrates (polymeric collagen fibrils and casein) employed in this study.