PubMed Health⌕ Search

Biomedical subjects

Chitra Sarkar

Publications and source records attributed to Chitra Sarkar.

At least 19 recordsLinked to original sources
PubMed2007

Uterus-like mass of müllerian origin in the lumbosacral region causing cord tethering. Report of two cases.

The presence of müllerian-origin tissue in the lumbosacral region is extremely uncommon. The authors report two cases of müllerian-origin tissue in that region. In the first case a 33-year-old woman harbored a conus medullaris mass lesion. Spinal dysraphism, tethered cord syndrome (TCS), and diastematomyelia were also present. In the second case a 24-year-old woman presented with low-back pain and a conus medullaris lesion, which was a cause of the TCS. Pathological examination in both cases revealed a uterus-like structure with evidence of fresh and old hemorrhage. The rarity of this lesion and its association with diastematomyelia requires documentation.

Adult↗
PubMed2006

Papillary glioneuronal tumour: a report of a rare case and review of literature.

INTRODUCTION: Amongst the mixed glioneuronal tumours, 'papillary glioneuronal tumour', a new variant, has been described recently. CASE REPORT: We report a case of papillary glioneuronal tumour in a 4-year-old boy who presented with fever, weakness of left upper and lower limbs and headache for the last 2.5 month. Radiologic examination showed a cystic space-occupying lesion with mural nodule in the right frontal lobe with extension into white matter. Surgical excision of a large cystic mass with small solid nodule was done. Pathological examination revealed a well-circumscribed tumour showing predominantly papillary architecture with focal aggregates of cells in sheets. The papillae were composed of hyalinised blood vessels lined by single to multi-layered cells. The tumour cells showed mild pleomorphism without any necrosis. The individual tumour cells had scant eosinophilic cytoplasm, round to oval hyperchromatic nucleus with occasional mitoses. The tumour cells were immunopositive for glial fibrillary acidic protein, synaptophysin, vimentin, and S-100 protein, but negative for neurofilament, epithelial membrane antigen, cytokeratin and CD34. MIB-1 labelling index was approximately 12% in the highest proliferating areas. In view of subtotal excision of the tumour and high MIB-1 labelling index (LI), the patient was given chemotherapy and he is doing well at 1-year follow-up. DISCUSSION: This report supports the existence of this rare tumour. Some of its rare clinicopathological features like young age, cyst with mural nodule, presence of mitoses and raised MIB-1 LI need to be documented.

Age Distribution↗
PubMed2006

Frequent loss of heterozygosity encompassing the hMLH1 locus in low grade astrocytic tumors.

The mismatch repair genes, hMLH1 (3p22) and hMSH2 (2p21), are commonly associated with accumulation of mutations and microsatellite instability. However, the status of their gene loci itself is often not addressed. In astrocytic tumors, the heterozygosity status of these genes with reference to tumor grade has not yet been determined. We have analyzed the heterozygosity status and locus specific instability in 43 glial tumors comprising 22 low grades diffuses astrocytoma (WHO Grade II, DA) and 21 glioblastoma multiforme (Grade IV GBM) using 10 microsatellite markers at 2p and 3p to elucidate the involvement of these loci in astrocytic tumorigenesis. We observed a significantly higher loss of heterozygosity (LOH) in 3p markers encompassing the hMLH1 gene locus in DA when compared to GBM (P = 0.008). In DA, while the frequency of LOH was observed to be higher in markers close to the hMLH1 gene ( approximately 40%), locus specific microsatellite instability (LSI) was higher ( approximately 30%) in markers localizing further to the gene. The frequency of LOH at markers on 2p, near the hMSH2 gene was, however, similar in DA and GBM (P = 0.451). Our results suggest that in the astrocytic tumorigenesis, LOH at the hMLH1 gene locus is an early event in tumorigenesis. However, the mismatch repair protein expression may be regulated by other cellular factors.

Adaptor Proteins, Signal Transducing↗
PubMed2006

Neuropathological spectrum of pilocytic astrocytoma: an Indian series of 120 cases.

Pilocytic astrocytomas (PAs) are generally well circumscribed, slowly growing, cystic tumors, occurring in the pediatric age group. Our aims were to retrospectively analyze the neuropathological spectrum of PA, and correlate it with various clinicopathological features. A total of 120 PAs, diagnosed and managed at this center during a 5-year period, were included. The study population had a mean age of 18.9 years, with male predominance (68.3%), and demonstrated predilection for posterior fossa (61.7%). On histopathology, biphasic pattern (89.2%) along with Rosenthal fibers (66.7%) and eosinophilic granular bodies (60%) were present in the majority of cases. Vascular features were characterized by perivascular hyalinization (51.7%), angiomatous proliferation (21.7%) and glomeruloid changes (21.7%). Hemosiderin-laden macrophages were noted in 37.1% of cases. Further, 60.8% showed lymphoplasmacytic infiltration, while atypia and necrosis were present in 25.8% and 1.7% of cases, respectively. Statistical evaluation revealed significant correlation of angiomatous proliferation with age (< or =12 and >12-year age groups) (p=0.011); and of hemosiderin deposition with angiomatous proliferation (p=0.006), perivascular hyalinization (p=0.035), and age (< or =12 and >12-year age groups) (p=0.028). This study emphasizes that though PAs generally display classical histomorphology, diagnosis may be challenging in patients with unusual clinicopathological features, e.g. in older patients, uncommon location, absence of biphasic pattern, or presence of nuclear atypia, mitotic figures and necrosis, and also in cases of small biopsies. In the absence of diagnostic histology enumerated above, vascular features like angiomatous proliferation, glomeruloid changes and perivascular hyalinization, along with hemosiderinladen macrophages and perivascular lymphocytic infiltration should be considered as surrogate histological markers of PA.

Adolescent↗
PubMed2006

Neurocytoma: a comprehensive review.

Central neurocytomas (CN) are uncommon tumors of the central nervous system, most descriptions of which available in the literature are in the form of isolated case reports and small series. Owing to this rare incidence, diagnosis and management of this neoplasm remain controversial. Usually, these tumors affect lateral ventricles of young adults and display characteristic neuroimaging and histomorphologic findings. Neurocytomas often mimic oligodendrogliomas when confirmation of diagnosis rests on immunohistochemistry, ultrastructure, and genetic studies. Extraventricular neurocytomas, situated entirely within the brain parenchyma and spinal cord, have also been reported. Typically, CN are associated with a favorable outcome although cases with more aggressive clinical course with recurrences are not unknown. MIB-1 labeling index (LI) of >2% often heralds poor prognosis and tumour recurrence. Safe maximal resection is presently considered the ideal therapeutic option, with best long-term prognosis in terms of local control and survival. The role of adjuvant radiotherapy apparently seems to benefit patients with incomplete resection and in atypical neurocytoma. Utility of other therapeutic regimen, however, remains shrouded in controversy. Epidemiology, histogenesis, clinical profile, histology, neuroimaging and therapeutic modalities of neurocytomas have been comprehensively reviewed, with special emphasis on CN and extraventricular neurocytomas and their atypical counterparts.

Age Factors↗
PubMed2006

Atypical neurocytoma of the spinal cord in a young child.

BACKGROUND: Extraventricular neurocytoma is a well-established entity, and non-classical sites like the cerebellum and spinal cord have occasionally been reported. CASE: We report a rare case of intramedullary neurocytoma in an 8-year-old boy who presented with paraparesis and urinary incontinence. This tumour was isointense on T1-weighted image and hyperintense on T2-weighted image, and showed heterogenous contrast enhancement. FINDINGS: Pathological examination showed atypical histology in the form of vascular endothelial proliferation, increased proliferation index, mitosis and necrosis. CONCLUSIONS: Atypical location, younger age and histopathological features are some of the interesting findings in this case, which need to be documented. To the best of our knowledge, this is the youngest patient of spinal cord neurocytoma.

Adult↗
PubMed2006

Angiogenic patterns and their quantitation in high grade astrocytic tumors.

BACKGROUND: The objectives of this study on high grade astrocytic tumors were (i) to establish differences, if any, between grades III & IV tumors among angiogenic parameters, both qualitative and quantitative, and (ii) to correlate angiogenic parameters with proliferation indices, namely T2a and MIB1 labeling indices. DESIGN: Twenty nine consecutive cases of WHO grades III (11) and IV (18) astrocytic tumors diagnosed in the year-2004 were studied, using H&E and CD34, MIB1 and T2a immunostaining by streptavidin biotin technique. Angiogenic patterns were studied and parameters quantitated using Image Pro Plus software (four hotspots) on CD34 immunostained sections to determine intratumoral microvessel density (iMVD), microvascular area (MVA), aspect, mean diameter (MD) and fractal dimension (FD). RESULTS: Main angiogenic patterns of capillary (18) and glomeruloid (9) types were best developed in glioblastomas. Statistically significant differences (P<0.05) were seen between grades III and IV in iMVD, aspect, MD and FD, but not in angiogenic patterns or MVA (P = 0.27). Statistically significant differences (P<0.05) were seen between glioblastomas with glomeruloid vs. capillary types in iMVD and FD, but not in MVA, aspect and mean vessel diameter. T2a values correlated with MIB1 labeling indices (R = 0.965, P<0.001). Intratumoral endothelial MIB1 LI was significantly higher in grade IV as compared to grade III, but did not correlate with angiogenic parameters. No correlation of angiogenic patterns and proliferation indices was noted (R = -0.221, P = 0.26). Limited follow up data showed all recurrent grade IV tumors to be of glomeruloid type. CONCLUSION: Increased angiogenesis in grade IV, as compared to grade III, astrocytic tumors is characterized by an increased number/density of vessels: an increase in vessels characterized by disproportionate lengthening and likely associated with the infiltrative properties of the tumors; and an increase in pliable, irregularly shaped or structured vessels. In addition, there is a greater frequency of glomeruloid structures indicating inadequate directional migration of the newly formed vessels. The lack of correlation of these angiogenesis parameters with the MIB1 and T2a proliferation indices reflects the complexity of angiogenesis parameters in high grade gliomas. Further studies are needed to determine the usefulness of the angiogenic parameters in the improved diagnosis (grading) and prognosis of astrocytic tumors.

Adolescent↗
PubMed2006

Gemistocytic astrocytomas: histomorphology, proliferative potential and genetic alterations--a study of 32 cases.

Gemistocytic astrocytomas (GAs) are a distinct variant of astrocytomas, generally classified as WHO grade II, and are associated with an aggressive biological behavior. This study was undertaken to determine the histomorphological spectrum, and correlate these with their proliferative potential and genetic alterations, in order to establish a biological basis for their unfavorable prognosis.A total of 32 GAs diagnosed during an 11-year period (1993-2003) were included in the study. Immunoreactivity for CD3 (T-cells), CD20 (B-cells) and CD68 (macrophages) were evaluated to characterize the perivascular inflammatory infiltrates, while p53, epidermal growth factor receptor (EGFR), cyclin D1 and p27-immunolabeling were studied to analyze the tumor biology.Overall, the mean gemistocytic index in the study was 39.6% (range, 12.2-80.8%), with multinucleation in gemistocytes and mitosis being present in 56.2% and 15.6% respectively. Perivascular mononuclear cell cuffing was seen in 56.2% cases, which was immunopositive for CD3 and CD68 in 14 cases each, with 13 cases being immunopositive for both. Similar type of inflammatory infiltrates was also present within the tumor parenchyma. Proliferation index depicted by MIB-1 LI was low (mean: 3.7%; range: 0.5-10.5%), with 70% cases having LI of <5%. MIB-1 labeling was restricted to the small astrocytic cells, similar to p27 and cyclin D1 immunoreactivity, both of which were present in 71.5% cases. In contrast, p53 protein expression was present in 75% cases, and was strongly positive in both gemistocytes and small cells, denoting neoplastic population. However, EGFR protein expression was consistently negative in all cases. Gemistocytes lack proliferative activity possibly indicating terminal differentiation, while small cells are the proliferating cells and their overall percentage may reflect the biological aggressiveness of these tumors and help to identify GAs of higher grade undergoing malignant progression. Therefore it appears that GAs should not be uniformly graded as grade II but should be subdivided into grades II and III neoplasms based on histological features and MIB-1 LI. The poor prognosis in GAs could be attributed both to the high frequency of p53 mutations and low p27 LI.

Adolescent↗
PubMed2006

Intracranial Rosai-Dorfman disease in a child mimicking bilateral giant petroclival meningiomas: a case report and review of literature.

UNLABELLED: OBJECTIVES AND IMPORTANCE: Rosai-Dorfman disease (RDD) is a rare but distinctive entity of unknown etiology; isolated intracranial RDD is uncommon. Of 37 reported intracranial RDD cases, only three were reported in children. CLINICAL PRESENTATION: We report an unusual case of a 15-year-old boy presenting with 4 months history of raised intracranial pressure with visual deterioration. Computed tomography and magnetic resonance imaging revealed bilateral petroclival enhancing lesions with cavernous sinus extension mimicking meningioma. However, histological examination was diagnostic of RDD. INTERVENTION: The patient underwent extended right-sided middle fossa approach and near-total tumor removal from petroclival region and cavernous sinus on both sides in two stages 6 weeks apart. CONCLUSION: Ours is the first case of pediatric isolated intracranial RDD presenting with giant bilateral petroclival masses successfully managed with bilateral extended middle fossa approach in two stages. An optimal treatment for RDD is not established, but complete surgical resection alone seems effective.

Adolescent↗
PubMed2006

Intracranial gliofibroma mimicking a meningioma: a case report and review of literature.

Gliofibromas are rare glio-mesenchymal tumors composed of astrocytic and benign mesenchymal components, which commonly occur in the first two decades of life. They are not listed as a distinct entity in the current WHO classification of CNS tumors. Their biological behaviour is unknown, and histogenesis is debatable. We describe a case of histopathologically proven gliofibroma in the region of the left quadrigeminal plate in a 15-year-old child that mimicked a tentorial meningioma both at imaging and surgery. Post-operatively, the residual tumor regrew to a size similar to the initial mass (4 cm x 3.6 cm x 3.5 cm), within one and a half years after the first surgery. The histopathology of the tumor was similar on both occasions. Although a poor prognosis has been characteristically noted in gliofibromas with high-grade glial component, but the present case had recurrence despite being of low-grade, thus highlighting the uncertain behaviour of this rare tumor.

Adolescent↗
PubMed2006

Recurrence in craniopharyngiomas: analysis of clinical and histological features.

The aim of this study was to investigate the recurrence patterns and significance of various clinical and histological features as predictors of recurrence in craniopharyngiomas. A series of 234 craniopharyngiomas (156 males, 78 females; age range 1.6-65 years) was reviewed. The mean follow-up period was 18.53 months (range 1-120 months). Peri-operative mortality was 7.4% and tumor recurrence was observed in 26 patients (20.3%). Of the patients with recurrence, one had total tumor excision (recurrence-free survival (RFS) 14 months), four had near-total excision (mean RFS 18.2 months) and 21 had subtotal tumor excision (RFS for symptomatic recurrence 7.1 months). Histologically, an adamantinous pattern was seen in 81.4% of cases and a papillary pattern was seen in 18.6%. Brain tissue was included in 67 cases and brain invasion was noted in 44 (all were of adamantinous histology). No correlation was noted between histopathological subtyping or brain invasion and recurrence. The significant clinical factors predictive of recurrence included the extent of resection, tumor size greater than 4 cm and cystic tumors.

Adolescent↗
PubMed2006

Medulloblastomas: new directions in risk stratification.

Medulloblastomas (MBs) are the most common malignant brain tumors in children. Current therapeutic approaches combine surgery, radiotherapy, and chemotherapy. Although, there has been significant improvement in long-term survival rates, the tumor remains incurable in about a third of patients while cognitive deficits and other sequelae of therapy are common among long-term survivors. Hence a major challenge remains to differentiate high-from low-risk patients and to tailor therapy based on the degree of biological aggressiveness. A clinical risk-stratification system has been widely used in MBs based on age, extent of resection and the Chang staging system. However, recent reports indicate that these clinical variables are inadequate methods of defining disease risk. This has prompted search for new markers for MB stratification. Recent studies indicate that the classification of MBs according to profiles of histopathology and molecular abnormalities possibly help better risk-stratification of patients, thereby rationalizing approaches to therapy, increasing cure rate, reducing long-term side effects and developing novel therapeutic strategies. The most accurate outcome prediction till date has been obtained through microarray gene expression profiling. In this article, the current histopathological classification and the recent advances in molecular genetics of MBs are reviewed. Global efforts to translate this knowledge of disease biology into clinical practice especially as outcome predictors are highlighted.

Brain Stem Neoplasms↗
PubMed2006

Comparative analysis of diagnostic accuracy of different brain biopsy procedures.

BACKGROUND: Image-guided procedures such as computed tomography (CT) guided, neuronavigator-guided and ultrasound-guided methods can assist neurosurgeons in localizing the intraparenchymal lesion of the brain. However, despite improvements in the imaging techniques, an accurate diagnosis of intrinsic lesion requires tissue sampling and histological verification. AIMS: The present study was carried out to examine the reliability of the diagnoses made on tumor sample obtained via different stereotactic and ultrasound-guided brain biopsy procedures. MATERIALS AND METHODS: A retrospective analysis was conducted of all brain biopsies (frame-based and frameless stereotactic and ultrasound-guided) performed in a single tertiary care neurosciences center between 1995 and 2005. The overall diagnostic accuracy achieved on histopathology and correlation with type of biopsy technique was evaluated. RESULTS: A total of 130 cases were included, which consisted of 82 males and 48 females. Age ranged from 4 to 75 years (mean age 39.5 years). Twenty per cent (27 patients) were in the pediatric age group, while 12% (16 patients) were >or= 60-years of age. A definitive histological diagnosis was established in 109 cases (diagnostic yield 80.2%), which encompassed 101 neoplastic and eight nonneoplastic lesions. Frame-based, frameless stereotactic and ultrasound-guided biopsies were done in 95, 15 and 20 patients respectively. Although the numbers of cases were small there was trend for better yield with frameless image-guided stereotactic biopsy and maximum diagnostic yield was obtained i.e, 87% (13/15) in comparison to conventional frame-based CT-guided stereotactic biopsy and ultrasound-guided biopsy. CONCLUSIONS: Overall, a trend of higher diagnostic yield was seen in cases with frameless image-guided stereotactic biopsy. Thus, this small series confirms that frameless neuronavigator-guided stereotactic procedures represent the lesion sufficiently in order to make histopathologic diagnosis.

Adolescent↗
PubMed2006

Neuropathological spectrum of lesions associated with intractable epilepsies: a 10-year experience with a series of 153 resections.

BACKGROUND: Surgical management of intractable epilepsies is currently an established mode of therapy in various clinical settings. AIMS: To retrospectively evaluate the neuropathological findings in both temporal and extratemporal lobe resections in such patients. MATERIALS AND METHODS: The study included resected specimens from patients with intractable epilepsy managed at a tertiary care hospital of India, during a 10-year period (1995-2004). RESULTS: A total of 153 patients, with mean age of 19.4 years and male predominance (73.2%) were included in the study. Overall, there was a predilection for the temporal lobe (73.2%), while 41cases were extratemporal in location. On histopathology, mesial temporal sclerosis (MTS) (24.8%) was the commonest lesion, followed by tumors (19.6%) and isolated focal cortical dysplasia (FCD - 15.11%). Other less common findings included Rasmussen encephalitis, non-specific gliosis and vascular malformations. In addition, 20.9% (32 cases) had dual lesions, majority of which included FCD with ganglioglioma (15 cases) or with dysembryoplastic neuroepithelial tumor (12 cases). In the temporal lobe, neoplasms and dual lesions formed the majority (apart from MTS), unlike dual lesions followed by neoplasms and FCD, in the extratemporal location. CONCLUSION: This series demonstrates that most patients with chronic intractable epilepsy have significant histopathological findings and highlights the neuropathological spectrum of such lesions, in the Indian context. This was similar to that reported from the West, but different from the single Indian series available in the literature. Further, the overall profile of temporal lobe lesions was not different from the extratemporal ones.

Adolescent↗
PubMed2005

Giant cell glioblastoma multiforme: report of a case with prolonged survival and transformation to gliosarcoma.

INTRODUCTION: Giant cell glioblastomas (GCGs) and gliosarcomas are rare histological variants of glioblastoma multiforme (GBMs). The mean age of occurrence in GCG is 42 years, but occasional cases have been documented in children under 10 years of age. Clinically, they are associated with a better prognosis than conventional GBMs, with few reports documenting prolonged survival up to 17 years after diagnosis. In contrast, gliosarcomas have age distribution and survival characteristics similar to conventional GBMs. They either arise de novo (primary) or secondary to irradiation to GBM. CASE REPORT: We report a rare case of childhood GCG in an 8-year-old boy surviving for more than 10 years since initial diagnosis. He has had two recurrences at the ages of 16 and 17 years, respectively, with histopathology at second recurrence showing evidence of gliosarcoma. DISCUSSION: No such case of gliosarcoma following treatment for GCG has been reported in the literature. Hence, the origin of the gliosarcoma whether radiation induced or only a phenotypic change in the GBM remains conjectural.

Adolescent↗
PubMed2005

Expression and structure of interleukin 4 receptors in primary meningeal tumors.

BACKGROUND: It was reported previously that malignant human tumors, like glioma and medulloblastoma, express high-density interleukin (IL-4) receptor mRNA and protein. Because IL-4 receptors (R) are sensitive targets for targeted therapeutics, knowledge of the expression of these receptors in other central nervous system tumors is of great interest. In this study, the authors examined the expression and subunit composition of IL-4R complex in primary human meningiomas. METHODS: Reverse transcription-polymerase chain reaction (RT-PCR) analysis for IL-13Ralpha1, IL-4Ralpha and IL-2Rgammac was performed on total RNA extracted from 35 meningiomas and a normal human brain tissue sample. Results were confirmed in nine randomly selected tumors by quantitative real-time PCR and in situ immunofluorescence assay. RESULTS: Transcripts for the IL-4Ralpha and IL-13Ralpha1 chains were overexpressed in meningiomas compared with normal brain tissue. The levels of IL-4Ralpha mRNA appeared to be higher compared with the levels of IL-13Ralpha1 mRNA. The results also showed that tumors with higher disease grade tended to have increased mRNA expression for the IL-4Ralpha chain. This IL-4Ralpha mRNA overexpression appeared to be more frequent in younger patients (age < 37 years). The transcripts for IL-2Rgammac chain were not detected in any of the tumor samples or in normal brain tissue. Quantitative real-time PCR confirmed the results of the RT-PCR analysis. Meningiomas also demonstrated a bright immunofluorescent staining for the IL-4Ralpha and IL-13Ralpha1 chains but no staining for IL-2Rgammac. CONCLUSIONS: Expression of the IL-4Ralpha and IL-13Ralpha1 chains and absence of IL-2gammac expression established that meningiomas expressed type II IL-4Rs. These receptors may serve as a target for cytotoxin/immunotoxin therapy in patients with meningioma who are not amenable to surgical resection or for recurrent tumors.

Adult↗
PubMed2005

Recurrence in pediatric craniopharyngiomas: analysis of clinical and histological features.

OBJECTIVE: The purpose of this study was to investigate the recurrence pattern and significance of various clinical and histological features as predictors of recurrence in pediatric craniopharyngiomas. METHODS: A series of 116 pediatric craniopharyngiomas (68 boys and 48 girls; age range, 1.6-18 years) was reviewed. Mean follow-up period was 18.53 months. Tumors recurred in 15 patients within 96 months [mean recurrence-free survival (RFS), 12.67 months]. Of the recurrence cases, 2 had complete (mean RFS, 16 months) and 13 had subtotal tumor excision (mean RFS, 9.03 months). Histologically, an adamantinous pattern was seen in 95% of cases, whereas a papillary pattern was noted in 5%. Brain tissue was included in 41 cases. In 32 of 41 cases, brain invasion was noted, and all were of adamantinous histology. No correlation was noted of histopathological subtyping or brain invasion with recurrence. CONCLUSIONS: The significant clinical factors associated with recurrence included extent of resection, tumor size >4 cm, and cystic tumors.

Adolescent↗