A clinicopathological study of primary central nervous system lymphomas & their association with Epstein-Barr virus.

Background & objectives: Primary central nervous system lymphomas (PCNSLs) are relatively uncommon, accounting for 2-3 per cent of primary brain tumours. Majority of these are diffuse large B cell lymphomas (DLBCL) occurring both in immunocompromised and immunocompetent patients. We undertook this study to classify PCNSL into germinal centre (GC) and non-germinal centre (NGC) type based on Hans classification and to find the role of Epstein-Barr virus (EBV) in pathogenesis both by conventional immunohistochemistry (IHC) and chromogenic in situ hybridization (CISH). Methods: The consecutive cases of PCNSL during a 10 years period were analysed by IHC for CD45, CD20, CD3, B-cell lymphoma 2 and 6 (Bcl-2 and Bcl-6), B-cell specific octamer binding protein-1 (BOB-1), multiple myeloma oncogene-1 (MUM-1), EBV latent-membrane protein 1 (LMP-1), cyclin-D1, CD10, CD5 and CD23, as well as by CISH for EBV. Results: During a period of 10 years, 65 PCNSL were diagnosed which comprised 0.69 per cent (65/9476) of all intracranial tumours. The mean age of presentation was 49 yr with sex ratio (M:F) of 1.4:1. Most common location was supratentorial region with predominant involvement of frontal lobe. Single lesions were seen in 38 (58.4%) and multifocal lesions in 27 (41.5%) patients. None of the patients were immunocompromised. All cases were B cell immunophenotype and were DLBCL except one case of follicular lymphoma. According to Hans classification, majority of them were NGC (n=51, 79.6%) and 13 (20.3%) were GC type. Bcl-2 expression was noted in 34 (52.3%) tumours. EBV was positive in three (4.6%) cases; two were detected both by IHC and CISH and one case by CISH only. Interpretation & conclusions: In Indian population, PCNSL occurs mainly in immunocompetent patients, and a decade earlier than in western population. Immunophenotyping revealed that all cases were DLBCL with predominance of NGC type. No prognostic difference was seen between GC and NGC DLBCL. Association of EBV was rare and this virus was possibly not involved in the pathogenesis of PCNSL in immunocompetent individuals. CISH was an easy, economical and less cumbersome method for detection of EBV in PCNSL.

1p/14q co-deletion: A determinant of recurrence in histologically benign meningiomas.

Background: Meningiomas are the most common benign central nervous system tumors. However, a sizeable fraction recurs, irrespective of histological grade. No molecular marker is available for prediction of recurrence in these tumors. Materials and Methods: We analyzed recurrent meningiomas with paired parent and recurrent tumors by fluorescence in situ hybridization for 1p36 and 14q32 deletion, AKT and SMO mutations by sequencing, and immunohistochemistry for GAB1, progesterone receptor (PR), p53, and MIB-1. Results: 18 recurrent meningiomas (11 grade I, 3 grade II, 4 grade III) with their parent tumors (14 grade I, 2 grade II and 2 grade III) were identified. Overall, 61% of parent and 78% of recurrent meningiomas showed 1p/14q co-deletion. Notably, grade I parent tumors showed 1p/14q co-deletion in 64% cases while 82% of grade I recurrent tumors were co-deleted. AKT mutation was seen in two cases, in both parent and recurrent tumors. SMO mutations were absent. GAB1 was immunopositive in 80% parent and 56.3% recurrent tumors. MIB-1 labeling index (LI), PR and p53 expression did not appear to have any significant contribution in possible prediction of recurrence. Conclusion: Identification of 1p/14q co-deletion in a significant proportion of histologically benign (grade I) meningiomas that recurred suggests its utility as a marker for prediction of recurrence. It appears to be a better predictive marker than MIB1-LI, PR and p53 expression. Recognition of AKT mutation in a subset of meningiomas may help identify patients that may benefit from PI3K/AKT pathway inhibitors, particularly among those at risk for development of recurrence, as determined by presence of 1p/14q co-deletion.

Thoracic neuroblastoma presenting as recurrent empyema.

Neuroblastoma is the most common intra-abdominal and extracranial solid tumour in children, accounting for 7%–8% of all childhood cancers. It is a malignant tumour of the autonomic nervous system derived from the neural crest. Most children with neuroblastoma have distant metastatic disease at the time of diagnosis. Pulmonary metastasis at the time of diagnosis is rare, and rarer is the presence of associated pleural effusion. We present the case of a child with recurrent empyema, who was diagnosed to have a thoracic neuroblastoma.

Mixed schwannoma with meningioma of the trigeminal nerve.

Mixed tumors composed of schwannoma and meningiomas are extremely rare and are usually associated with neurofibromatosis-2 (NF-2). So far, all the cases reported have involved the cerebello-pontine angle. Only two cases did not have a clear association with NF-2. We report a mixed tumor comprising of meningioma admixed with schwannoma in a 33-year-old male with bilateral trigeminal nerve schwannomas. The patient did not fit the existing diagnostic criteria of NF-2. The relevant literature, along with diagnostic criteria for NF-2 is discussed.

Malignant hemangiopericytoma of pituitary fossa.

Intracranial hemangiopericytomas are rare tumors with aggressive behavior. Other than the meninges, this lesion has rarely been reported in periventricular and sellar region. We report a case of malignant hemangiopericytoma in sellar region in a 47-year-old male who presented with history of sudden onset of bilateral visual disturbances. To best of our knowledge, this is the second case report of malignant hemangiopericytoma in this location. As this intracranial lesion shows aggressive behavior, in the form of recurrence or extracranial metastasis in comparison to its extracranial counterparts, diagnosis should be made cautiously.

Gliomatosis cerebri.

A 6-year-old boy who presented with worsening hemiplegia, behaviour problems and seizures after an episode of encephalitis-like illness is reported. MRI revealed diffuse signal change and swelling of the left cerebral hemisphere. The diagnosis of gliomatosis cerebri was confirmed by brain biopsy. Parents refused radiotherapy and the child worsened and died 6 months after diagnosis.

Myoepithelial carcinoma of soft tissue: a case report.

Myoepithelioma of soft tissue is a recently categorized entity and myoepithelial carcinoma is extremely rare. We describe a case of myoepithelial carcinoma of soft tissue in a 30-year-old male patient, who presented with a painless mass located at the back of left leg involving popliteal fossa that was present since childhood. A wide local excision was performed. The distinct histopathological features included infiltrative margins, cytologically moderate to severely atypical epithelioid/spindled cells with prominent nucleoli, 3-4 mitoses/10HPF, tumor necrosis and lymphovascular invasion. No heterologous elements were identified. The myoepithelial origin was confirmed by positive immunohistochemical staining for S100 protein, epithelial membrane antigen and smooth muscle actin. Mib-1 (Ki-67) proliferation index was 20-25%. These carcinomas have variable clinical presentation and can have an indolent course for several years. Recognition of myoepithelial carcinoma is clinically significant because compared to its benign counterpart, this has increased frequency of local recurrences and metastases that warrants a close clinical follow-up.

Application of domestic microwave for urgent histopathology reporting: an evaluation.

Rapid diagnosis of histopathological material is becoming increasingly desirable. In neuropathology, crush smear preparation and frozen section diagnosis of tissues removed during operative procedures, have remained as essential tools for rapid diagnosis. Microwave technology has been introduced into the field of tissue processing and staining in past decade. Now-a-days even automated microwave assisted rapid tissue processors are available. In our study we have analysed the use of a domestic microwave (cost approximately Rs.5000) for urgent histoprocessing (30 minutes). This could be useful in small laboratories or the ones which are in the phase of establishing the department as the procedure is much more economical than obtaining a frozen section (which requires a cryostat worth 3-6 lakhs) and the interpretation of the section obtained does not require any extra experience as these resemble the routinely processed tissue sections. The advantages and limitations of the procedure have been discussed.

Blood collection procedures in hematology: knowledge and practice among laboratory personnel.

Blood collection is an important preanalytical component of haematological testing. This questionnaire based study was conducted on laboratory personnel to elicit their knowledge and practice regarding blood collection procedures for haematological testing. Questionnaire comprised of 37 multiple choice questions, of which 10 questions each were related to essential and desirable knowledge, 10 to practice and 7 to educational and job profile. Ninety four laboratory personnel participated in the study. Analysis was done on SPSS software. Percentages of unsatisfactory scores were 42.6%, 4.3%, 17% and 6% in the essential knowledge, desirable knowledge, practice and total scoring respectively. 91.5%, however, had a satisfactory total score. Importance needs to be given to blood collection procedures both, individually and collectively. The study highlights the deficient areas which need to addressed by all laboratorians. Such studies should also be conducted among nursing and resident staff- the other groups concerned with blood collection.

Histological spectrum of ependymomas and correlation of p53 and Ki-67 expression with ependymoma grade and subtype.

BACKGROUND: Clinical and histological criteria for ependymoma prognosis are well recognized. Recently few studies have been done based on Immunohistochemistry for prognostication of these tumours. In this study we have correlated the histological spectrum with immmunoexpression of p53 and Ki67 in these tumors. AIMS: To know the incidence of ependymomas; study their morphological spectrum and to evaluate expression of P53 and Ki 67 in different morphological subtypes. MATERIAL AND METHOD: A retrospective study was preformed on 70 ependymomas received in a period between 1994 and 2001. Entire tissue received was processed for routine paraffin embedded H&E stained sections. Immunocytochemistry was performed using antibodies to GFAP, EMA, Pancytokeratin and synaptophysin, to differentiate papillary ependymoma from choroid plexus papilloma; clear cell ependymoma from oligodendroglioma and central neurocytoma; ependymoblastoma from other embryonal tumours. p53 and Ki-67 immunohistochemistry was performed to correlate their expression with various tumour grades and subtypes. RESULTS: There were 3 cases (4.2%) of Grade I ependymoma (2 cases of myxopapillary ependymoma and 1 case of subependymoma); 57 cases (81.5%) of ependymoma grade II (43 of these were of classical variety, 11 of clear cell ependymoma, 2 of papillary and 1 case of cellular ependymoma). There were 9 cases (12.8%) of anaplastic ependymoma (one of these was a clear cell ependymoma and 1 case (1.5%) of ependymoblastoma CONCLUSION: p53 and Ki67 indices can be used in routine diagnostic laboratories to supplement the tumor grade on histology and more studies with follow up should be performed to analyse the prognosis of different subtypes. The expression of Ki 67 and p53 was significantly higher in anaplastic ependymomas. 4 out of 11 cases of clear cell ependymomas showed higher Ki 67 indices as compared to classical grade II ependymomas, thus further highlighting the importance of differentiating the various subtypes.

Histological analysis of cystic tumour like lesions of central nervous system.

True cysts of the central nervous system (CNS) are rare lesions. A retrospective study of patients with symptomatic non-neoplastic cystic lesions of CNS operated in the Department of Neurosurgery, G.B. Pant Hospital, New Delhi between Jan 1994 and Feb 2001 was conducted. Parasitic cysts, cystic transformation of hemmorhages, vascular malformations and cystic tumours were excluded from the study. A total of 109 cases were reviewed. There were 34, 27, 17, 16, 8, 3 and 2 cases of epidermoid, arachnoid, dermoid, colloid, neurenteric, Rathke's and ependymal cysts and 1 case each of choroid plexus and glial cysts. The clinical presentations, locations, incidence and pathogenesis of these cysts is discussed.