Comparative ultrastructural study of cytotoxic granules in nasal natural killer cell lymphoma, intestinal T-cell lymphoma, and anaplastic large cell lymphoma

Clinical features and treatment outcome of chordoid meningiomas in a single institute

Objective

Meningioma is the second most common primary central nervous system neoplasm. In contrast, chordoid meningioma is rare; due to the paucity of cases, little is known about its clinical features or treatment outcomes. The objectives of this study were to describe the clinical characteristics and outcomes for patients with chordoid meningioma.

Methods

In total, 16 patients, with newly diagnosed chordoid meningioma who underwent surgical excision between 1999 and 2012 were included. We retrospectively evaluated the medical records, radiological findings, and pathological findings. The median follow-up period was 56.5 (range, 3-170) months. The MIB-1 labeling index ranged from 1 to 26.60% (median, 5.04).

Results

Simpson grade I, II, and III resections were performed in four, nine, and three patients, respectively. The overall recurrence rate was 37.5%. Overall progression-free survival (PFS) after resection was 94.7 months (95% CI=62.9-126.6). Of the 4 patients with Simpson grade I resection, recurrence occurred in one patient. Among the Simpson grade II and III resection groups, eight patients underwent adjuvant radiation therapy and they showed significantly longer PFS (121 months, 95% CI=82.1-159.9) than the patients who underwent surgery alone (40.5 months, 95% CI=9.6-71.3) by the log-rank test (p<0.05).

Conclusion

Chordoid meningiomas are difficult to manage and have a high rate of recurrence. Complete resection of the tumor is a key determinant of better outcomes. Adjuvant radiation therapy is recommended, eparticulary when Simpson grade I resection was not achieved.

Expression of granzyme B sensitizes ALK+ ALCL tumour cells to apoptosis-inducing drugs

Background

The serine protease Granzyme B (GzB) is primarily expressed by cytotoxic T lymphocytes and natural killer cells, and functions in allowing these cells to induce apoptosis in virally-infected or transformed cells. Cancers of both lymphoid and non-lymphoid origin also express GzB, and in some cases this expression has been linked to pathogenesis or sensitizing tumour cells to cell death. For example, GzB expression in urothelial carcinoma was implicated in promoting tumour cell invasion, whereas its expression in nasal-type NK/T lymphomas was found to correlate with increased apoptosis. GzB expression is also a hallmark of the non-Hodgkin lymphoma, anaplastic lymphoma kinase-positive, anaplastic large cell lymphoma (ALK+ ALCL). Given the fact that ALK+ ALCL exhibits high levels of apoptosis and is typically responsive to conventional chemotherapy, we examined whether GzB expression might play a role in sensitizing ALK+ ALCL tumour cells to apoptosis.

Methods

ALK+ ALCL cell lines stably expressing GzB or non-targeting (control) shRNA were generated and apoptosis was examined by anti-PARP western blotting and terminal deoxynucleotidyl transferase dUTP nick end labelling. Both spontaneous apoptosis and apoptosis in response to treatment with staurosporine or doxorubicin were investigated. In order to assess whether additional granzymes might be important in promoting cell death in ALK+ ALCL, we examined whether other human granzymes were expressed in ALK+ ALCL cell lines using reverse-transcriptase PCR and western blotting.

Results

Expression of several GzB shRNAs in multiple ALK+ ALCL cell lines resulted in a significant decrease in GzB levels and activity. While spontaneous apoptosis was similar in ALK+ ALCL cell lines expressing either GzB or control shRNA, GzB shRNA-expressing cells were less sensitive to staurosporine or doxorubicin-induced apoptosis as evidenced by reduced PARP cleavage and decreased DNA fragmentation. Furthermore, we found that GzB is the only granzyme that is expressed at significant levels in ALK+ ALCL cell lines.

Conclusions

Our findings are the first to demonstrate that GzB expression sensitizes ALK+ ALCL cell lines to drug-induced apoptosis. This suggests that GzB expression may be a factor contributing to the favourable response of this lymphoma to treatment.

Light scattering and morphology of the lymphocyte as applied to flow cytometry for distinguishing healthy and infected individuals

A simple optical model of single lymphocytes with smooth and nonsmooth surfaces has been developed for healthy and infected individuals. The model can be used for rapid (in the real-time scale) solution of the inverse light-scattering problem on the basis of optical data measured by label-free flow cytometry. Light scattering patterns have been calculated for the model developed. It has been shown that the smooth and nonsmooth cells can be resolved using the intensities of the sideward- and backward-scattered light. We have found by calculations and validated by the flow cytometer experiments that intensity distributions for the cells of lymphocyte populations can be used as a preliminary signatures of some virus infections. Potential biomedical applications of the findings for label-free flow cytometry detection of individuals infected with viruses of hepatitis B or C and some others viruses are presented.

Anaplastic large cell lymphoma: another entity in the differential diagnosis of small round blue cell tumors

We saw in consultation a biopsy specimen from a 6-year old girl with anaplastic lymphoma kinase (ALK)-positive anaplastic large cell lymphoma (ALCL). The tumor arose in soft tissue of the neck, and diagnostic tissue was obtained by core needle biopsy. Histologically, the neoplasm was cellular without pattern. Immunohistochemical workup with a large panel of antibodies at another institution showed immunoreactivity for NB84 and neuron specific enolase (dim). Antibodies specific for CD3, CD20, and CD45/LCA were negative; CD30 or ALK were not assessed. Electron microscopy showed cytoplasmic structures thought to be neurosecretory granules. The neoplasm was interpreted initially as a neuroblastoma. At the time of our review, we considered the possibility of ALCL. Immunohistochemical analysis for CD30 showed bright, uniform expression and ALK was positive in a nuclear and cytoplasmic pattern, confirming the diagnosis of ALK+ ALCL. The purpose of this review is to discuss ALK+ ALCL and many of the other entities included under the rubric of small round blue cell tumor, with a focus on tumors that occur in children.

Validation of an integrated Raman- and angular-scattering microscopy system on heterogeneous bead mixtures and single human immune cells

A microscopy system has been constructed that is capable of simultaneously acquiring both Raman spectra and angle-resolved elastic-scattering patterns in either epi- or transillumination modes with a 7 mum spot size. The benefits and drawbacks of the epi- and transillumination modalities are discussed. Validation studies have been performed on single beads of a few micrometers in size, as well as on ensembles of submicrometer particles. In addition, transilluminated Raman and elastic-scattering spectra were obtained from single granulocytes and peripheral blood monocytes. Both the Raman- and the elastic-scattering channels show clear differences between the two types of immune cells.

Iatrogenic metastasis of a benign meningioma to the periosteum at the site of previous craniotomy: a case report

Metastasis formation after resection of meningiomas is a rare event, predominantly occurring with malignant phenotypes. As far as we know, the presented case is the first report in the literature of iatrogenic seeding of a benign meningioma to the scalp following surgery. A 37-year-old woman was admitted because of a relapsing meningioma in the frontal lobe. In 1997, she had undergone complete excision of an atypical meningioma in same location. At follow-up, three new masses were found: a bifrontal meningioma on the edge of the falx, a smaller one in the falx just under the saggital sinus and a small mass, believed to be ectopic, in the periosteum at the site of the previous craniotomy. Surgical therapy was indicated. Histologically, the ectopic tumor was an atypical meningioma, similar to the one excised 10 years previously, with no relation to the other two intracranial masses. Because of the histological similarity and the location in the old craniotomy, the ectopic tumor was believed to have developed from an implantation metastasis as a consequence of the first surgery. The authors suggest that strict adherence to oncological principles should be applied in the case of benign neoplasms in order to prevent contamination of wounds with tumor cells and potential recurrence.

CD8+, CD56+ (natural killer-like) T-cell lymphoma involving the small intestine with no evidence of enteropathy: clinicopathology and molecular study of five Japanese patients

The present study reports five CD8+, CD56+ (natural killer (NK)-like) T-cell lymphomas involving the small intestine without evidence of enteropathy, from Japan. Three were intestinal T-cell lymphoma. The site of origin of the other two was not definitive. Four of five patients underwent emergency operation because of intestinal perforation. The small intestines of these patients had multiple ulcerative lesions with or without demarcated tumors. Histologically, the lymphoma cells were monomorphic or slightly pleomorphic and displayed epitheliotropism of varying degrees. Lymphoma cells of all patients shared the common phenotype: CD3+, CD4-, CD5-, CD8+, CD56+, CD57-, T-cell intracellular antigen-1+, granzyme B+. In contrast to nasal/nasal type NK-cell lymphomas, they had clonal rearrangement of T-cell receptor(TCR) genes and were negative for EBV-encoded RNA. Immunohistochemistry and genetics suggested that three cases were of alpha beta T-cell origin and two cases were of gamma delta T-cell origin. There was no evidence of enteropathy in any patient. The cases followed a clinically aggressive course with a frequent involvement of lung. According to the classification based on the recent genetic studies of European enteropathy-type intestinal T-cell lymphoma (ETL), the present cases could be classified as type 2 ETL.

A unique case of adolescent CD56-negative extranodal NK/T-cell lymphoma, nasal type

Mature T-cell neoplasms are unusual in the pediatric population. The majority of these neoplasms in the United States are anaplastic large cell lymphomas (ALCL) characterized by CD30 and anaplastic lymphoma kinase-1 expression. Extranodal natural killer/T (NK/T)-cell lymphomas, nasal type, are extremely rare. Extranodal NK/T-cell lymphomas often express CD56, are associated with Epstein-Barr virus, and are negative for CD30. Clinically, extranodal NK/T-cell lymphomas are much more aggressive than ALCL, and require different treatment strategies. The authors present an adolescent male with a CD56 negative extranodal NK/T-cell lymphoma, nasal type. The lymphoma was partially positive for CD30, diffusely positive for EBV by in situ hybridization, and clonal for T-cell receptor gene rearrangement and cytogenetic abnormalities. The patient was aggressively treated with chemotherapy, surgery, and radiation. More than 2 years from completion of the therapy, the patient remains disease free. This case highlights the importance and difficulty of accurate identification of this type of rare tumor. We further present the literature review and discuss the diagnostic criteria for extranodal NK/T lymphoma using morphologic, immunologic, molecular, and cytogenetic information.

Rapid biogenesis and sensitization of secretory lysosomes in NK cells mediated by target-cell recognition

Natural killer (NK) cells play important roles in defense against tumor, viral infection, and cell-mediated xenograft rejection through secretion of secretory lysosomes. In this study, we used high time-resolution membrane capacitance measurement and fluorescence-imaging techniques to study the biogenesis and exocytosis of secretory lysosomes in a human NK cell line. We demonstrated a high-affinity Ca(2+)-dependent exocytosis of secretory lysosomes, which is sensitized further after target-cell stimulation. Our data also suggest an unusual rapid and dramatic de novo formation of secretory lysosomes after target-cell recognition. The rapid biogenesis of secretory lysosomes was blocked by specific protein kinase C inhibitor but not by brefeldin A. We propose that target-cell recognition triggers rapid biogenesis and sensitization of secretory lysosomes in NK cells through activation of PKC.

Hepatosplenic T cell lymphoma with no expression of cytotoxic molecules

Hepatosplenic T cell lymphoma is defined as an extranodal and systemic neoplasm derived from cytotoxic T cells. This report describes a postmortem case of T cell lymphoma that showed histological features of hepatosplenic T cell lymphoma but did not express cytotoxic molecules. The patient was a 57 year old man who presented with severe icterus and hepatosplenomegaly, followed by an aggressive clinical course. The liver and spleen were enlarged, weighing 2000 g and 360 g, respectively. Histologically, the liver, spleen, and bone marrow were entirely affected by lymphoma, comprising pleomorphic small and large cells, which displayed sinusoidal infiltration in the liver, diffuse infiltration in the splenic cord, and interstitial/diffuse infiltration with fibrosis in the bone marrow. Lymphoma cells showed positivity for CD3 epsilon, CD8, and CD45RO and clonal rearrangement of the TCRgamma gene by the polymerase chain reaction on paraffin wax embedded sections. However, they were negative for TIA-1 and granzyme B, in addition to betaF1, CD4, and CD56. Few neoplastic cells were stained for Epstein-Barr virus encoded mRNA 1. These findings indicate that this case might represent a variant of hepatosplenic T cell lymphoma despite the absence of cytotoxic molecules.

Seeding of malignant meningioma along a surgical trajectory on the scalp. Case report and review of the literature

The authors report the case of an 11-year-old boy with a malignant meningioma of the right frontal meninges. The tumor was asymptomatic, despite visible exophytic extracranial growth. Neuroimaging demonstrated an en plaque meningioma bulging into the brain. Six months after the tumor had been totally removed by surgery, an isolated subcutaneous metastasis developed at the right preauricular area of the scalp, originating at the scar left by the first surgery. After removal of this metastasis, radiotherapy was conducted. To date the follow-up examinations have not revealed any additional metastases. To the best of the authors' knowledge, this is the first report of a seeding of a subcutaneous metastasis in a child with a malignant meningioma. The authors review the literature with reference to malignant meningiomas and their formation of metastasis. In cases of malignant meningiomas, piecemeal tumor removal carries the risk of iatrogenic cell dissemination even when precautions are taken.