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C Sarkar

Publications and source records attributed to C Sarkar.

At least 19 recordsLinked to original sources
PubMed2006

Anaplastic ependymoma with cartilaginous and osseous metaplasia: report of a rare case and review of literature.

Gliomas with cartilaginous metaplasia are extremely uncommon and thought to be due to metaplasia of the mesenchymal supportive elements. The tumors are located in the midline, mostly fourth ventricle and rarely in the pons. The present paper describes an unusual case of anaplastic ependymoma with cartilaginous and osseous metaplasia in a young boy which was located in the suprasellar, interpeduncular prepontine and left cerebello-pontine cistern. To the best of our knowledge, this cartilaginous metaplasia in ependymomas has been reported only thrice.

Bone Neoplasms↗
PubMed2006

Clear cell meningioma, an uncommon variant of meningioma: a clinicopathologic study of nine cases.

AIMS: Clear cell meningioma (CCM) is an uncommon variant of meningioma, which affect younger patients, occur more often in spinal or cerebello pontine locations and shows a higher recurrence rate. Only few case reports have been described in the literature. The study has been undertaken to document the clinicopathological features of nine cases of CCM, operated at All India Institute of Medical Sciences during 1998 to December 2005. METHODS: Clinical information was retrieved from the records of our Neurosurgery Department. The cases were stained with H&E, periodic Acid Schiff (PAS) with and without diastase. Immunohistochemistry for pancytokeratin, epithelial membrane antigen, vimentin, glial fibrillary acidic protein, and MIB-1 was done in all cases. RESULTS: During a period of 8 years, nine cases of CCM were diagnosed. Age ranged from 10 to 65 years (median age 26.0 years) with female predominance. Most common location was posterior fossa (CP angle). Clinically most of the patients presented with history of headache and features of cranial nerve palsies. The duration of symptoms varied from 3 to 60 months (mean 16.7 and median of 4 months). Radiologically lesions showed homogenous enhancement and were isointense to brain parenchyma. Histopathologic examination revealed tumor cells to be arranged in sheets with clear cytoplasm and monomorphic nuclei. MIB-1 labeling index (LI) ranged from 2 to 12% with a mean of 9%. Follow up varied from 3 to 84 months (median 36 months) and recurrence was noted in two patients after 2 and 3 years of surgery, respectively, despite their low MIB-1 labeling indices. CONCLUSIONS: CCM is a rare variant of meningioma with poor outcome. Less than 50 cases have been described in the literature. Low rate of recurrence and recurrence despite their low MIB-1 LI are some of the features, which needs to be documented. Hence, larger number of cases with adequate follow-up data need to be studied further to establish the clinical significance of this variant.

Adolescent↗
PubMed2006

Chordoid meningioma, an uncommon variant of meningioma: a clinicopathologic study of 12 cases.

AIMS: The study has been undertaken to document the clinicopathological features of 12 cases of chordoid meningioma, operated at All India Institute of Medical Sciences during 1996 to June 2005. METHODS: Clinical information was retrieved from the records of our Neurosurgery Department. The cases were stained with H&E, Periodic Acid Schiff (PAS) with and without diastase, mucicarmine, giemsa, toluidine blue, alcian blue, reticulin and Masson trichrome. Immunohistochemistry for pancytokeratin, epithelial membrane antigen, vimentin, glial fibrillary acidic protein, MIB-1, Leucocyte common antigen (LCA), CD-3 and CD-20 was done in all cases. RESULTS: The age ranged from 12-67 years (mean 34.2 years) and three of them occurred in < 18 years. Male to female ratio was 1:1.4. The duration of symptoms varied from 3.5 months to 5 years (mean 14.1 months). No systemic symptoms were noted. The location of tumor in eight cases was in the supratentorial and rest four in the infratentorial compartments. Interestingly, two cases were in intraventricular location, one in the lateral ventricle and other in the fourth ventricle. Microscopic examination showed lobulation with chordoid elements constituting > 95% of the entire tumor area in 11 of the total 12 cases. In one case, chordoid pattern constituted about 30% of the total tumor area; the rest was predominant meningothelial (60%). Mild to severe lymphoplasmacytic cell infiltrate was present in all cases. The histochemical stains showed the pattern of acidic mucin and interestingly revealed the presence of mast cells both in connective tissue stroma and epithelial cell islands. The inflammatory infiltrate was B-cell predominant. MIB-1 labeling index was low (< 2%) in all cases except two, which showed LI of 6% and 8%. Strong diffuse immunoreactivity for vimentin and focal positivity for epithelial membrane antigen was noted in all cases. CONCLUSIONS: Chordoid meningiomas are predominantly tumors of young adults with predilection for supratentorial location. Intraventricular location, absence of systemic manifestations despite the presence of abundant B-lymphocytes, presence of mast cells and low MIB-1 LI are some of the interesting findings in the present series, which need documentation. Hence, larger number of cases with adequate follow-up data need to be studied further to establish the clinical significance of this variant.

Adolescent↗
PubMed2006

Expression of CD34 as a novel marker for glioneuronal lesions associated with chronic intractable epilepsy.

The spectrum of glioneuronal lesions underlying intractable epilepsies includes malformative pathologies like focal cortical dysplasia (FCD); and neoplastic lesions like gangliogliomas (GG) and dysembryoplastic neuroepithelial tumours (DNT). These may occur either singly or as dual lesions, having simultaneous presence of both elements. Currently, the relationship between the malformative and neoplastic glioneuronal lesions is poorly understood. Recently, CD34, a stem cell marker transiently expressed during early neurulation, has been identified in these tumours. This study was undertaken to (i) evaluate the role of CD34 as a diagnostic marker for glioneuronal lesions of epilepsy, namely, GG, DNT and FCD, and (ii) attempt to define the relationship among these lesions, using CD34 as a marker. Tissues resected from 47 patients with intractable epilepsy due to glioneuronal lesions (GG, FCD, DNT) were studied. These were evaluated for CD34 expression, using immunohistochemistry. Dysplastic or atypically differentiated neural precursors which could not be identified on routine haematoxylin and eosin (H&E) staining were highlighted by CD34 immunostaining. The pattern of immunostaining was diffuse in GGs, unlike FCDs, wherein cells were present singly or in small clusters. However, cases of DNT and control tissue were largely CD34-immunonegative. Based on these findings, we propose a possible common origin of GG and FCD, from a bipotent precursor that undergoes abnormal glioneuronal development, while DNTs possibly have a different origin. The CD34-immunoreactive cells represent dysplastic or undifferentiated neural precursors, which may signify a valuable marker for the diagnostic evaluation of neoplastic and/or malformative pathologies in patients with intractable epilepsy.

Adolescent↗
PubMed2005

Endoscopic assisted excision of a retroclival arachnoid cyst presenting as hysterical breathlessness.

BACKGROUND: Arachnoid cysts are benign developmental cysts occurring most commonly in the middle fossa. Posterior fossa arachnoid cysts are less common, with retroclival arachnoid cysts especially in the pediatric age group being rare. PATIENTS AND METHODS: We present a case of a retroclival interpeduncular farachnoid cyst in a 10-year-old boy who presented with left-sided ptosis and episodes of hysterical breathlessness. RESULTS: The surgical treatment involved endoscopic assisted microsurgical excision of the cyst and the child made an uneventful and complete recovery with complete cessation of breathlessness. The clinical presentation, etiopathogenesis, imaging characteristics and treatment modalities are discussed and the relevant literature reviewed.

Arachnoid Cysts↗
PubMed2005

Morphology of angiogenesis in human cancer: a conceptual overview, histoprognostic perspective and significance of neoangiogenesis.

This paper reviews the histomorphological aspects of angiogenesis and neoangiogenesis, quantitative and qualitative, and their applications in prognostic evaluation of neoplastic diseases. The merits and weak points of intratumoral microvessel density (MVD), a widely regarded bona fide predictor of tumour growth, metastases and patient survival, are discussed. Total microvascular area (TVA) has been found useful in recent prognostic studies utilizing newer immunohistochemical vascular markers. Of particular significance is the fact that MVD and TVA are most predictive of patient outcome in those tumours that induce significant neoangiogenesis, namely carcinomas of breast and prostate, and haematological malignancies. In contrast, carcinomas of lung and urinary bladder do not show significant associations of MVD and TVA with poor prognosis, reflecting differences in angiogenic mechanisms. In gliomas, MVD appears to correlate with outcome in high-grade, but not low-grade tumours, and does not correlate with tumour cellularity in the infiltrating portions of the tumour, reflecting a paucity of neoangiogenesis and directional vascular growth. Recent studies have found CD105, Tie-2/Tek and vascular endothelial growth factor receptors to be the best markers of neoangiogenesis. The vascular parameters so measured correlate better with overall and disease-free survival in breast, colon and lung carcinoma than panendothelial markers such as CD31. A correlation of vascular patterns with prognosis has been established in ocular melanomas, glioblastomas and squamous carcinomas of head and neck region. Vascular networks with closed loops are closely associated with mortality due to metastases in uveal melanomas. Fewer bizarre glomeruloid vessels and prominent classical capillary pattern was an independent predictor of longer survival in glioblastoma. Therefore a judicious combination of quantitative and qualitative microscopic angiogenic parameters, with emphasis on neoangiogenesis and vascular patterns wherever applicable, should be an integral component of a more consistent tumour staging system for accurate prognostic evaluation of tumours, selection of optimal anti-angiogenic therapy and pertinent research.

Humans↗
PubMed2005

Desmin-related myopathy: report of a rare case.

The Protein Surplus Myopathies (PSM) are characterized by accumulation of protein aggregates, identifiable ultrastructurally, resulting due to mutations of the encoding genes. Desmin-related myopathies (DRM) are a form of PSM characterized by mutations of the desmin gene resulting in the formation of protein aggregates comprising mutant protein desmin and disturbance of the regular desmin intermediate network in the muscle fibers. We describe a rare case of DRM in a 23-year-old man who presented with complaints of difficulty in climbing stairs and running since the age of 5 years. EMG studies revealed a myopathic pattern. Muscle biopsy showed the features of muscular dystrophy with bluish rimmed vacuoles and sarcoplasmic inclusions, which were immunoreactive to desmin. Ultrastructural examination showed sarcoplasmic bodies and granulofilamentous inclusions. Although rare, the possibility of DRM/desminopathy should be considered in the presence of bluish rimmed vacuoles on light microscopy and characteristic ultrastructural inclusions. To the best of our knowledge this is the first case of DRM/desminopathy reported from India.

Adult↗
PubMed2005

Recurrent lymphocytic hypophysitis in a woman 27 years after subtotal adrenalectomy for hypercortisolism possibly of autoimmune origin.

Lymphocytic hypophysitis commonly occurs in females in peripartum period but several unusual presentations have been reported. Here we report a rare case of recurrent lymphocytic hypophysitis in a woman who had subtotal adrenalectomy for hypercortisolism 27 years back. Polyglandular autoimmune endocrinopathy with an uncommon combination of Cushing's syndrome and recurrent hypophysitis is a strong possibility in this case. Treatment with steroids has been found to have beneficial effect.

Adrenalectomy↗
PubMed2004

Primary lumbosacral Wilms tumor associated with diastematomyelia and occult spinal dysraphism. A report of a rare case and a short review of literature.

BACKGROUND: The occurrence of an extrarenal Wilms tumor in the lumbosacral region is an extremely uncommon condition. CASE REPORT: We report a case of Wilms tumor in the lumbosacral region that was associated with diastematomyelia and occult spina bifida. An 18-month-old girl presented with a swelling over the lower back with a tuft of hair on it, which she had had since birth. Imaging of the spine revealed spina bifida, bony diastematomyelia, and tethered cord. Excision of the bony spur and detethering of the cord was done. After a year, she had recurrence of swelling at the same site, weakness of both lower limbs, and incontinence of bladder and bowel. Excision of the mass and bony spur and detethering of the spinal cord were done. Histopathological examination showed features of a Wilms tumor.

Female↗
PubMed2004

Leigh's syndrome.

A 15-month-old female child presented with sudden onset cough and hyperventilation along with evidence of metabolic acidosis. She had past history of recurrent vomiting, episodes of abnormal posturing, difficulty in deglutition and regression of milestones since 12 months of age. CT scan of the brain revealed hypodense lesions in bilateral basal ganglia and on MRI there were T2 hyperintensities in bilateral lentiform nuclei, caudate nuclei, thalamus, red nuclei and dentate nuclei. Biochemical examination revealed persistently elevated serum lactate levels with high lactate/pyruvate ratio. Resuscitative measures were of no avail and the child succumbed to the illness on the second day of admission. Neuropathological examination at autopsy demonstrated marked spongiosis, focal necrosis, endothelial proliferation, reactive astrogliosis and extensive demyelination involving bilateral basal ganglia, midbrain and spinal cord which were typical of Leigh's sub acute necrotizing encephalomyelopathy.

Autopsy↗
PubMed2004

Giant mucoceles of the frontal sinus: a series and review.

Giant mucoceles of the frontal sinus are a rare pathology but their recognition is important in the differential diagnosis of paediatric proptosis and fronto-orbital lesions. Four patients with giant mucoceles of the frontal sinus were retrospectively analyzed. All the patients were females in the paediatric age group presenting with massive cosmetically unacceptable bony swelling in the frontal region along with unilateral extra-axial proptosis. Radiological imaging revealed giant mucoceles of the frontal sinus with extracranial, orbital and anterior cranial fossa extension. One patient had co-existent craniofacial fibrous dysplasia. Single stage surgery was performed in three patients and two-stage surgery in one. Fronto-orbital craniotomy, removal of the posterior wall of the sinus, obliteration of the sinus and its ostium, dural repair and remodeling cranioplasty were performed. Histopathological examination revealed mucoceles in all, and co-existant fibrous dysplasia in one patient. All the patients made excellent cosmetic recoveries with complete resolution of their visual symptoms. Their clinical presentation, radiological manifestations and treatment modalities are analyzed and an extensive review of the literature is presented. Our case of giant frontal mucocele associated with fibrous dysplasia is furthermore the first such report in the existing medical literature.

Adolescent↗
PubMed2004

No evidence of hSNF5/INI1 point mutations in choroid plexus papilloma.

Choroid plexus carcinomas (CPC) have been shown to carry mutations in the hSNF5/INI1 gene on chromosomal arm 22q11.2. A recent study on choroid plexus papillomas (CPP) and CPC revealed frequent losses of chromosomal portions on the long arm of chromosome 22 (-22q). The region harbouring hSNF5/INI1 was affected in 47% of the CPP and 73% of the CPC, respectively. -22q occurred more frequently in adult than in infantile CPP suggesting different pathogenetic pathways for these tumours. These findings may indicate a potential tumour suppressor gene function of hSNF5/INI1 in a subset of choroid plexus tumours. In order to examine its potential role in the pathogenesis of choroid plexus tumours, we analysed exons 1-9 of hSNF5/INI1 by SSCP analysis in a series of 21 formalin-fixed and paraffin-embedded CPP. No alterations in migratory patterns were detected. These data indicate that somatic point mutations of hSNF5/INI1 do not play a role in the pathogenesis of CPP and that CPP and CPC may arise by two different molecular pathways.

Choroid Plexus Neoplasms↗
PubMed2004

Congenital fiber type disproportion: a rare type of congenital myopathy: a report of four cases.

Congenital fiber type disproportion is a rare type of congenital myopathy which presents as hypotonia, delayed motor milestones and dysmorphic facies. During the past 2 years we received 449 muscle biopsies, of which 4 cases were diagnosed as congenital fiber type disproportion (CFTD). In addition to CFTD, one case also had centronuclear features. Three of them were females and one was a male child. Although rare, it should be considered in the differential diagnosis of childhood muscle diseases. Histochemical staining is necessary for the diagnosis of this entity.

Adolescent↗
PubMed2003

Clear cell odontogenic carcinoma: a diagnostic dilemma.

A 26-year-old man presented with a swelling in the right side of face and CT scan revealed a destructive tumor in the right maxilla. Tumor recurred within 5 years of its excision and histopathological examination revealed a clear cell odontogenic carcinoma. The rarity of this tumor, occurrence in maxilla and young age of the patient are some of the rare features which need documentation. The importance of its diagnosis and various differential diagnoses are discussed.

Adenocarcinoma, Clear Cell↗
PubMed2003

Large cystic fibrous dysplasia of the temporal bone: case report and review of literature.

Fibrous dysplasia is an uncommon benign disorder of unknown aetiology. It most likely represents a disorder of normal bone development. As it may occasionally involve the temporal bone, and encroach on the middle cranial fossa, it is of interest to the neurosurgeon. Fibrous dysplasia of the cystic variety is very uncommon. We report a case of a large cystic fibrous dysplasia involving predominantly the squamous temporal bone. The radiology and histology are discussed, and its differentiation from other lesions.

Craniotomy↗
PubMed2003

Selective mitochondrial KATP channel activation by nicorandil and 3-pyridyl pinacidil results in antiarrhythmic effect in an anesthetized rabbit model of myocardial ischemia/reperfusion.

The roles of cardiomyocyte sarcolemmal ATP-sensitive K+ (KATP) and mitochondrial KATP channels in cardioprotection and antiarrhythmic activity induced by KATP channel openers remain obscure. However, it has been suggested that the mitochondrial KATP channels are involved as a subcellular mediator in cardioprotection afforded by ischemic preconditioning. In the present study, we investigated the effects of the administration of non-hypotensive doses of ATP-sensitive K+ channel (KATP) openers (nicorandil and 3-pyridyl pinacidil), a specific mitochondrial KATP channel blocker (5-hydroxydecanoate) and a specific sarcolemmal KATP channel blocker (HMR 1883; 1-[5-[2-(5-chloro-o-anisamido)ethyl]-2-methoxyphenyl]sulfonyl-3- methylthiourea) prior to and during coronary occlusion, as well as prior to and during post-ischemic reperfusion, on survival rate, ischemia-induced and reperfusion-induced arrhythmias and myocardial infarct size in anesthetized albino rabbits. The thorax was opened in the left 4th intercostal space and after pericardiotomy the heart was exposed. In Group I (n = 80), occlusion of the left main coronary artery and hence, myocardial ischemia-induced arrhythmias were achieved by tightening a previously placed loose silk ligature for 30 min. In Group II (n = 186), arrhythmias were induced by reperfusion following a 20 min ligation of the left main coronary artery. In both Group I and Group II, early intravenous infusion of nicorandil (100 micrograms/kg bolus + 10 micrograms/kg/min), 3-pyridyl pinacidil (3.0 micrograms/kg bolus + 1.0 microgram/kg/min), HMR 1883 (3 mg/kg)/nicorandil and HMR 1883 (3 mg/kg)/3-pyridyl pinacidil, just prior to and during ischemia, increased survival rate (75%, 67%, 86% and 75% vs. 60% in the control subgroup in Group I; 67%, 75%, 75% and 67% vs. 43% in the control subgroup in Group II), significantly decreased the incidence and severity of life-threatening arrhythmias and significantly decreased myocardial infarct size. However, late intravenous administration of nicorandil or 3-pyridyl pinacidil at the onset of and during reperfusion did not increase survival rate nor confer any antiarrhythmic or cardioprotective effects. The antiarrhythmic and cardioprotective effects of both nicorandil and 3-pyridyl pinacidil were abolished by pretreating the rabbits with 5-hydroxydecanoate (5 mg/kg, i.v. bolus), a selective mitochondrial KATP channel blocker, but not by pretreatment with HMR 1883 (3 mg/kg). In the present study, higher levels of malondialdehyde (MDA) and lower levels of reduced glutathione (GSH) and superoxide dismutase (SOD) in the necrotic zone of myocardium in all sixteen subgroups in Group II suggest little anti-free radical property of nicorandil and 3-pyridyl pinacidil. Therefore, we may conclude that intervention by intravenous administration of nicorandil and 3-pyridyl pinacidil (through the selective activation of mitochondrial KATP channels), increases survival rate and exhibits antiarrhythmic and cardioprotective effects during coronary occlusion and reperfusion in anesthetized rabbits, when administered prior to and during coronary occlusion. The mitochondrial KATP channel may be considered to be a potentially important site of cardioprotection and antiarrhythmic activity.

Animals↗
PubMed2003

August 2002: 21-year-old male with cystic intracerebral tumor.

The August 2002 COM. A 21-year-old male presented with a single episode of generalized tonic clonic seizures. Radiology revealed a cystic tumor with mural nodule suggestive of a pilocytic astrocytoma. However, histopathological examination and electron microscopy revealed features of an intracerebral schwannoma. Therefore, although rare, in an intracerebral cystic lesion with mural nodule, the possibility of an intracerebral schwannoma should be entertained. This is important because this is a benign tumor with favourable response to resection.

Adult↗