Biomedical subjects

Chitra Sarkar

Publications and source records attributed to Chitra Sarkar.

At least 37 records · Page 2Linked to original sources

PubMed2005

Recent advances in embryonal tumours of the central nervous system.

INTRODUCTION: Embryonal tumours of the central nervous system (CNS) are the commonest malignant paediatric brain tumours. This group includes medulloblastomas, supratentorial primitive neuroectodermal tumours, atypical teratoid/rhabdoid tumours, ependymoblastomas, and medulloepitheliomas. Earlier, all these tumours were grouped under a broad category of primitive neuroectodermal tumours (PNETs). However, the current WHO classification (2000) separates them into individual types based on significant progress in the understanding of their distinctive clinical, pathological, molecular genetic, histogenetic, and behavioural characteristics. Furthermore, advances in histopathology and molecular genetics have shown great promise for refining risk assessment in these tumours, especially medulloblastomas, thus providing a more accurate basis for tailoring therapies to individual patients. Correlation of histological changes with genetic events has also led to a new model of medulloblastoma tumorigenesis. REVIEW: This review presents an updated comparative profile of these tumours, highlighting the clinical and biological relevance of the recent advances.

Age Distribution↗

PubMed2005

Meningioangiomatosis with meningioma: an uncommon association of a rare entity--report of a case and review of the literature.

INTRODUCTION: Meningioangiomatosis (MA) is a rare lesion, probably of malformative origin, consisting of meningovascular proliferation and leptomeningeal calcification. Patients with MA usually present with seizures or persistent headaches. Neurofibromatosis may be associated in a variable proportion of patients, while in others it may be sporadic. Surgical treatment is usually recommended, and is gratifying in most cases. Rarely, MA has been described coexisting with meningiomas, arteriovenous malformations, encephaloceles, oligodendrogliomas, meningeal haemangiopericytomas and orbital erosion. Among these, meningiomatosis with meningioma is the most frequent combination. CASE REPORT: We report a case of MA with meningioma in an 18-month-old girl, who presented with recurrent seizures. DISCUSSION: In these situations, it is extremely important for the pathologist to be aware of this entity and to distinguish it from other lesions, like cortical invasion by a meningioma, intraparenchymal meningioma and intracerebral schwannoma, which it may mimic.

Angiomatosis↗

PubMed2005

Primary central nervous system lymphoma--a hospital based study of incidence and clinicopathological features from India (1980-2003).

Over the last two decades, an increase in the incidence of PCNSL cases has been reported in the West, both among immunosuppressed and immunocompetent patients. The present study was undertaken to assess the trend of incidence of PCNSL cases in India. To the best of our knowledge, only a single such report is available from India. All biopsy proven PCNSL cases obtained from the Neurosurgical databases of two large referral hospitals, one in Northern India (AIIMS, New Delhi) and another in Southern India (NIMHANS, Bangalore) from the period 1980 to 2003, were reviewed. Immunophenotyping was done and relevant clinical details collected. Appropriate statistical analysis was done to assess any change in trend of incidence or age at presentation. PCNSL cases constituted 0.95% and 0.92% of the total intracranial neoplasms at AIIMS and at NIMHANS, respectively. The mean age for cases diagnosed at AIIMS was 44.35 years, while that for NIMHANS was 39.51 years. Statistical analysis to evaluate any change in trend either of incidence or of age at presentation, over the study period, did not reveal any significant change. All the cases occurred in immunocompetent patients, except one case of HIV positive at NIMHANS, and one case of renal transplant at AIIMS. Frontal lobe was the most common site of involvement. Majority of the cases were diffuse, high grade, large cell lymphoma, B-cell immunophenotype. Thus, this multicentric hospital based study did not reveal any increase in incidence of PCNSL cases in India over the past 24 years. Further, in contrast to the West, majority of the cases in this Indian study were immunocompetent and a decade younger than in the West. The association of PCNSL with HIV/AIDS has been low in India, possibly due to early death in AIDS on account of opportunistic infections.

Adolescent↗

PubMed2005

Apoptosis and proliferation: correlation with p53 in astrocytic tumours.

Apoptosis and cell proliferation occur simultaneously in tumour tissue with tumour suppressor gene, p53 being one of the key players in the complex relationship between these two key phenomena. We, as well as several other groups, have earlier demonstrated the association of p53 immunopositivity with increased degree of cell proliferation in astrocytic tumours. Here we have studied the extent of apoptosis in 62 primary human astrocytic tumours [25 Diffuse Astrocytoma (DA), 9 Anaplastic Astrocytoma (AA) and 28 Glioblastoma multiforme (GBM)] in relation to tumour grade, proliferative status and p53 protein expression. Apoptosis was measured by the TUNEL assay while, cell proliferation (MIB-1 index) and p53 protein immunoreactivity were evaluated by immunohistochemical staining using MIB-1 and DO-1 monoclonal antibodies respectively. The apoptotic index (AI) was greater in GBM than in AA or DA, and more in tumours with p53 immunopositivity than in those without. The most striking observation was the strong correlation between Apoptotic index (AI) and proliferation index (PI) in p53 negative GBM (r=0.766, P < 0.005). However this was not observed in p53 +ve GBM or in low grade DA either p53 positive or negative. Taking p53 negativity in IHC as evidence of a functional gene/protein, this extends the link between proliferation and apoptosis, hitherto observed only in cultured cells with functional p53, to a subset of solid tumours.

Apoptosis↗

PubMed2005

Primary neurocytoma of the spinal cord: a case report and review of literature.

Most central neurocytomas (CN) and spinal neurocytomas (SN) have a bland well-differentiated histologic picture and uneventful clinical course. However, rare examples showing histologic atypia, recurrence and even CSF dissemination have been reported. Herein we report a case of recurrent spinal neurocytoma in a 24-year-old male who presented with a 2-month history of weakness and numbness of the left upper and lower limbs, and was previously operated at the same site 10 months ago. MRI revealed a contrast enhancing intramedullary mass involving C5-T1 region. Radiologic and operative impression at both surgeries was that of a glioma, possibly anaplastic. Histologic and immunohistochemical features in both resections were those of an atypical neurocytoma. The tumor showed rare mitoses, focal mild vascular proliferation in both specimens, and necrosis in the initial specimen. MIB1 labeling indices were 9 and 10%, respectively. Based on the analysis of this case and limited data from the literature, it is hypothesized that SN shows a histopathologic picture, immunoprofile and biologic behavior very similar to CN. However, the presence of histologic atypia and increased MIB1 index in SN appear to more closely correlate with tumor recurrence and a worse overall outcome, in part due to their location in the critical region of cervical spinal cord. Therefore, we hypothesize that SN with atypia requires a close clinical follow up. As in CN, radiation therapy is perhaps best reserved for atypical, progressive and recurrent SN.

Adult↗

PubMed2005

Cerebellopontine angle paraganglioma - report of a case and review of literature.

Majority of the cerebellopontine angle (CPA) tumors are acoustic neuromas, while bulk of the non-acoustic tumors are formed by meningiomas and epidermoid cysts. Primary paraganglioma is a rare tumor in this location, with only two such cases having been reported in the literature, till date. Recently, a case has been described wherein a paraganglioma was apparently arising as a primary lesion in the cerebellar hemisphere. We report another case of an intracranial paraganglioma of the CPA in a 40-year-old female, which did not have any vascular attachment but had focal cerebellar extension.

Adult↗

PubMed2005

Intraventricular glioneuronal hamartoma: histopathological correlation with magnetic resonance spectroscopy.

Intraventricular hamartomas are extremely uncommon lesions outside of a setting of tuberous sclerosis. The second case of its kind in medical literature is presented and its possible aetiopathogenesis, imaging characteristics, pathognomonic magnetic resonance spectroscopy (MRS) and histopathology are discussed. An 11-year-old male presented with a seizure disorder for one year, with headache and vomiting for 15 days. Computerized tomography (CT) revealed a non-enhancing, heterogeneous, left-sided, trigonal lesion with areas of calcification trapping the left frontal horn. Magnetic resonance imaging (MRI) indicated that the lesion was iso to hypointense on T1 weighted images (T1WI) and iso to hyperintense on T2 weighted images (T2WI). A pathognomonic neurochemical signature was elicited on (1)H MRS showing low N-acetylaspartate resonance and normal creatine:choline ratios. Radical decompression of the tumor resulted in an excellent outcome. The diagnosis was established by positive immunohistochemical reactivity for synaptophysin, glial fibrillary acidic protein (GFAP) and myelin basic protein. This is the first case report in existing medical literature in which a histopathological correlation is available for a hamartoma with an unequivocal MRS signal. The authors advocate the use of MRS in patients with tuberous sclerosis or neurofibromatosis with suspected hamartomas to distinguish these benign lesions from gliomas prior to a surgical exploration.

Cerebral Ventricles↗

PubMed2005

Orbital paraganglioma: report of a rare case.

CASE REPORT: Paragangliomas of the orbit are extremely rare tumors. We report a well-documented case of orbital paraganglioma in a 45-year-old man who presented with proptosis and decreased vision. The patient underwent complete excision of the tumor with preservation of orbital structures. There was total regression of symptoms after surgery and vision was well maintained. COMMENTS: Radiological and pathological features are described and differential diagnoses of this entity are discussed.

Biomarkers, Tumor↗

PubMed2005

Orbital ectopic glial tissue in relation to medial rectus: a rare entity.

Heterotopic brain tissue is a rare entity and it is rarer still in the orbit. There have been very few case reports of orbital ectopic glial tissue. The case is described herein of a 3-month-old baby presenting with an orbital glial hamartoma inseparable from the medial rectus muscle. The diagnosis was based on the histopathological features and a positive GFAP stain. The features of this case and the previously reported cases are discussed.

Brain↗

PubMed2005

Neuropathological spectrum of Rasmussen encephalitis.

BACKGROUND: Rasmussen encephalitis (RE) is a chronic epileptic disorder of unknown etiology, and is clinically characterized by progressive neurological deterioration, focal seizures often progressing to intractable epilepsy, cognitive decline and hemispheric atrophy. AIMS: We report the spectrum of neuropathological changes seen in RE, and discuss the evolutionary mechanisms of this disease. MATERIALS AND METHODS: Surgically obtained specimens from RE patients diagnosed during 2002-2004 at this institute were evaluated for the presence and extent of different histopathological features of RE. The H&E and immunohistochemistry stained slides were also evaluated for the type and distribution pattern of inflammatory infiltrates, along with a semiquantitative evaluation for the severity of inflammation. RESULTS: Four cases of RE were admitted during the study period, all of which presented with partial seizures with successive deterioration to intractable epilepsy. The age at onset varied between 5 and 10 years (mean 7.8 years), with three male and one female patients. Subsequently, all four patients underwent hemispherotomy. Histopathological features of perivascular lymphocytic infiltrate, neuronal loss, microglial nodules, and reactive astrocytosis, with or without evidence of neuronophagia confirmed a diagnosis of RE. These cases also had varying degrees of T-cell-rich (CD3-positive) inflammatory infiltrates and CD68-immunopositive microglial proliferation. It was observed that the severity of inflammation had a trend to inversely correlate with the duration of symptoms. CONCLUSION: It is proposed that an accurate evaluation and histopathological grading of these lesions may possibly have a role in patient prognostication.

Brain↗

PubMed2005

Hallervorden spatz disease: MR and pathological findings of a rare case.

We describe a child with pathologically proven Hallervorden Spatz disease. He presented with extrapyramidal symptoms and characteristic "eye-of-the-tiger" sign on magnetic resonance imaging. He was given the possible benefit if any of deep brain stimulation with no much improvement. Pathological examination of the brain showed iron deposition in bilateral globus pallidi, spongiform change and neuron axonal degeneration (spheroids).

Child↗

PubMed2005

Glioblastoma multiforme with long term survival.

Glioblastoma multiforme (GBM) Patients generally have a dismal prognosis, with median survival of 10-12 months. GBM with long-term survival (LTS) of (3) > or = 5 years is rare, and no definite markers indicating better prognosis have been identified till date. The present study was undertaken to evaluate GBMs with LTS in order to identify additional correlates associated with favourable outcome. The cases were evaluated for relevant clinicopathological data, proliferation index and expression of tumortumour suppressor gene (p53 ), cyclin-dependant kinase-inhibitors (p27 and p16 ) and epidermal growth factor receptor (EGFR) proteins. Six cases of GBM with LTS with an average survival of 9 years (range 5-15 years) were identified. All were young patients with mean age of 27 years (range 8-45 years). Histology of three cases was consistent with conventional GBM, while two showed prominent oligodendroglial component admixed with GBM areas. One was a giant cell GBM, which progressed to gliosarcoma on recurrence. The mean MIB-1LI was 12% (range 6-20%). p53 was immunopositive in 4 out of 5 cases. EGFR and p27 were immunonegative in all, whereas p16 was immunonegative in 3 out of 5 cases. Currently, in the absence of specific molecular and genetic markers, GBM in young patients should be meticulously evaluated for foci of oligodendroglial component and/or giant cell elements, in addition to proliferative index and p53 expression, since these probably have prognostic connotations, as evident in this study. The role of p16 and p27 however needs better definition with study of more number of cases.

Adolescent↗

PubMed2004

Subependymal giant cell astrocytoma--a clinicopathological study of 23 cases with special emphasis on histogenesis.

Subependymal giant cell astrocytomas (SEGAs) are relatively rare tumors but occur commonly in the setting of the familial syndrome of tuberous sclerosis complex (TSC). In view of its varied morphology, i.e. resemblance to astrocytic and ganglion cells, its histogenesis remains controversial. We studied 23 cases of SEGA, 19 from our own institute and 4 from NIMHANS, Bangalore. These 19 cases of SEGAs were collected over a period of 23 years (1979 to 2001), and accounted for 0.16% of intracranial tumors and 0.51% of all gliomas reported at our center. The majority of patients presented with visual disturbances (19/23, 82.6%) in the form of decreased vision (60.8%) and blindness (21.7%), generalized tonic clonic seizures (43.4%) and focal motor seizures (4.37%). Age ranged from 4 to 37 years (mean 13.2 years) with male predominance (M:F 2.2:1), and the duration of symptoms varied from 1 month to 96 months (mean 17.2 months). Lateral ventricular involvement was the most common site (91.3%), followed by the third ventricle (8.6%). Nine patients (39.1%) had stigmata of tuberous sclerosis (6 at the time of diagnosis and 3 in the follow-up period). Two patients died due to surgical complications, while the rest were alive and well in the follow-up period ranging from 3 to 264 months (mean 37.1 months). Two patients experienced recurrences, one two years and another 22 years after surgery. Microscopic examination showed varied histology consisting of sweeping bundles of spindle cells, gemistocyte and ganglion-like cells with interspersed inflammatory cell component. The inflammatory cell component on special staining turned out to be an admixture of mast cells and T lymphocytes. Six cases showed areas of necrosis and/or mitosis, but were not indicative of aggressive nature of this tumor. Immunoreactivity for GFAP, NF, S-100, NSE and synaptophysin indicates that this is a hybrid tumor with glial and neuronal differentiation. None of the tumors was immunopositive for HMB-45. The significance of the presence of T lymphocytes and mast cells is not clear. It could be related to tumor immunology and may indicate a favorable prognosis.

Adolescent↗

PubMed2004

Fungal granuloma of the brain caused by Cladosporium bantianum--a case report and review of literature.

Involvement of the brain by neurotropic, dematiaceous fungi namely Cladosporium bantianum is extremely rare. The disease is very resistant to treatment and prone for frequent relapses despite treatment with amphotericin B and flucytosine, the drugs of choice for the infection. Surgery is often required for resection of the fungal granuloma. Isolation of the fungus from the tissue specimens and its culture, showing dark colored fungal colonies clinches the diagnosis. Animal inoculation studies can provide insights to the portal of entry of the organism. We hereby report a case of fungal granuloma of the brain due to C. bantianum, which responded favorably to intensive antifungal treatment alone, with relevant review of literature.

Adult↗

PubMed2004

Supratentorial glioblastoma in adults: identification of subsets and their clinical correlation.

The concept of different genetic pathways leading to glioblastoma multiforme (GBM) has gained considerable acceptance, and two major groups are now described, primary or de novo GBM and secondary GBM. The present study was undertaken to elucidate whether additional pathways exist and to determine whether there is any correlation between these different variants and clinical parameters, such as age, duration of symptoms, and outcome. For this purpose, immunophenotyping was performed to study the simultaneous expression of p53 protein and epidermal growth factor receptor (EGFR) in 58 cases of adult supratentorial GBM. By this method, four variants of GBM could be distinguished: 34% were p53 positive only, 38% were EGFR positive only, 14% were double negative (p53 negative/EGFR negative), and 14% were double positive (p53 positive/EGFR positive). Interestingly, all nine cases of secondary GBM in which there was clinical and histological evidence of progression from a preexisting low-grade lesion were p53 positive. Differences were observed with regard to the age distribution of the four variants, in that the p53 negative/EGFR negative tumors occurred most frequently in the younger age group (21-40 years). In the elderly group (61-80 years), two-thirds of the tumors were p53 negative/EGFR positive primary GBMs, and no case of the double positive or double negative variant was encountered. The differences in duration of symptoms and symptom-free survival according to age group and genetic subset were not statistically significant. There were no differences in outcome within each age category for any GBM variant, although the longest mean symptom-free survival was noted among patients aged 41-60 years with the p53 positive/EGFR negative variant. This study therefore indicates that at least four subsets of GBM exist, but despite different genotypes, the biologic behavior remains similar. Other genetic alterations therefore need to be investigated to identify prognostic makers.

Adult↗

PubMed2004

Central core disease.

Central core disease is a congenital myopathy characterized by generalized hypotonia, muscle weakness and presence of central cores on muscle biopsy. It generally presents during infancy. It is familial with autosomal dominant inheritance [Chromosome 19q13.1; Gene Locus RyR1 (Ryanodine receptor gene)]. We report here two cases of central core disease in a 3-year-old male child and 8 year old female child.

Activities of Daily Living↗

PubMed2004

Muscular dystrophies and related skeletal muscle disorders in an Indian population--a prospective correlative study.

Since most centers in developing countries have limited facilities for investigation of patients with muscular dystrophies and similar disorders, this study was conducted with the aim of assessing the correlation between clinical, electromyographic (EMG) and histopathological findings in this group. We included 100 patients with muscular dystrophy and clinically similar disorders and subjected them to detailed clinical, electrophysiological and histopathological as well as immunohistochemical evaluation. Sensitivity, specificity, positive and negative predictive values and concordance rates for clinical and EMG diagnosis compared to diagnosis after histopathological examination were analyzed. With histopathology as standard, clinical diagnosis and a concordant EMG have very high sensitivity and negative predictive value (100%), but low specificity (33.3%). We conclude that detailed histopathological evaluation with immunohistochemical analysis is essential for the work-up of patients with suspected muscular dystrophies, since occasionally treatable muscle disorders like inflammatory myopathies can be detected when not suspected clinically. Muscle biopsies should only be conducted at major centers where full histochemical facilities are available.

Adolescent↗

PubMed2004

Allergic fungal sinusitis: expanding the clinicopathologic spectrum.

OBJECTIVE: We sought to determine whether histologic tissue invasion occurs in allergic fungal sinusitis (AFS) and, if so, to identify clinical indicators for the same. Study design and setting We conducted a retrospective case record review of all 28 AFS cases identified by histology over a 32-month period at a tertiary care referral center. All histologic specimens were reevaluated for features of invasive pathology, and case records were correlated for clinical, radiologic, or laboratory parameters associated with such invasion. RESULTS: In addition to the universal finding of the characteristic allergic mucin with fungal elements on histopathologic examination of the sinus luminal contents, 6 cases (21%) had additional evidence of mucosal invasion as indicated by granulomatous inflammation and branching septate fungal hyphae in the submucosal tissues. Such coexistent invasion was associated with advanced disease as indicated by a higher incidence of orbital involvement on clinical evaluation (P = 0.024), and extrasinus spread (intraorbital or intracranial spread) on the computed tomography evaluation (P = 0.003). The single death that occurred on follow-up was in a patient with coexistent invasion. CONCLUSION: Advanced AFS may be complicated by histologic evidence of tissue invasion. SIGNIFICANCE: The noninvasive and invasive forms of fungal sinusitis are not necessarily discrete and may coexist in the same patient. Clinical features of orbital involvement or computed tomography manifestations of extrasinus spread should alert the clinician to the possibility of invasion.

Adolescent↗