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C Sarkar

Publications and source records attributed to C Sarkar.

At least 37 records · Page 2Linked to original sources
PubMed2003

A comparative study of classical vs. desmoplastic medulloblastomas.

Classical and desmoplastic medulloblastomas (MBs) have been suspected to be biologically different, though comparative studies on markers of biological aggressiveness in these two variants are sparse in the literature. 87 classical and 43 desmoplastic variants of MB were studied with respect to clinical and histological characteristics, MIB-1 labeling index (MIB-1 LI), apoptotic index (AI), ratio of AI to MIB-1 LI, expression of p53 and Bcl-2 protein and 3-year progression-free survival. The only differences documented between the variants were with regard to age distribution and location. Thus, classical histology cases occurred predominantly in children and 80% were midline in location. In contrast, lateral location was seen more frequently with tumors of desmoplastic histology, which occurred in an almost equal distribution between children (56%) and adults (44%). No difference was noted between the variants with regard to proliferation index, apoptotic index, their ratio on or their molecular controls (p53 and Bcl-2). This was reflected in the clinical outcome wherein no significant difference was observed in the 3-year progression-free survival between the variants. It is concluded that the two histological variants of medulloblastoma are not different with regard to biological parameters of aggressiveness. The growth rate and clinical outcome in medulloblastomas have no correlation with the histological variant.

Adolescent↗
PubMed2003

Primary osteosarcoma of the skull. A report of 3 cases.

Osteosarcomas are malignant bone tumors, which commonly affect the long bones of young adults. Primary osteosarcomas of the skull are exceedingly rare. We herein report 3 cases of primary osteosarcoma of the skull involving the calvaria, diagnosed over a period of 8 years at the Department of Pathology of our Institute.

Adolescent↗
PubMed2003

Clinicopathological study of spinal teratomas. A series of 10 case.

AIM: Sacrococcygeal teratomas are common in children, but intramedullary spinal teratomas are rare. We report a series of 10 cases of spinal teratomas, which, to the best of our knowledge, is the largest series of intramedullary teratomas. METHODS: During a period of 15 years (1987-2001) 10 cases of spinal teratomas were diagnosed in our department. The clinical profile, radiological data and histopathological slides were reviewed. RESULTS: Age ranged from 10 months to 51 years (mean 23.5 years) with male predominence. Duration of symptoms varied from 5 months to 20 years (mean 4.1 years). The most common symptoms were weakness of lower limbs, backache and urinary bladder involvement. Radiologically, these were heterogenous lesions with fat signal and areas of calcification. Surgery is the treatment of choice. Only 1 case recurred after 9 years of operation. CONCLUSION: Although there are no specific features on imaging of intramedullary teratomas, solid and cystic morphology, fat signal and areas of calcification are some of the helpful features. Most of these lesions are diagnosed on histopathological examination after surgery. Surgery is the treatment of the choice.

Adult↗
PubMed2003

Cerebrotendinous xanthomatosis: neuroimaging findings in two siblings from an Indian family.

Cerebrotendinous xanthomatosis (CTX) is exceptionally rare in the Indian population. We present and discuss the clinical, radiological and histopathologic findings in 2 siblings with CTX. Both the patients had juvenile cataract, mental retardation and marked cerebellar ataxia. The Achilles tendon swelling was present in only 1 patient (Case 2). MR imaging showed typical bilateral and symmetrical involvement of the dentate nuclei, inferior olives, brainstem and cerebellar hemispheric white matter. Although the diagnosis of CTX was made in the 3rd decade in both our cases, early diagnosis is possible if neuroimaging is done in the early course of the disease.

Adult↗
PubMed2003

Merosin negative congenital muscular dystrophy: a short report.

We report a rare case of an infant with congenital muscular dystrophy who presented at birth with marked generalized hypotonia and normal mental development. Creatinine phosphokinase (CPK) level was markedly raised; however no white matter abnormalities were detected by brain imaging techniques. Immunohistochemical staining for merosin (laminin alpha 2) was negative, thereby confirming merosin-deficient congenital muscular dystrophy.

Female↗
PubMed2002

A melanotic desmoplastic medulloblastoma: report of a rare case and review of the literature.

A 28-year-old man had a desmoplastic medulloblastoma in the vermis and left cerebellum. This tumor was composed of nodular, reticulin-free zones (pale islands) surrounded by densely packed, highly proliferative cells that produced a dense intercellular reticulin network. Some of the cells were heavily pigmented, and this pigment proved to be melanin. Adult age, desmoplastic nature, and melanin pigmentation are some of the rare features of this tumor that need documentation. Further, this pigment was in the primitive cells, unlike in the published cases, in which it was present in the tubular or tubulopapillary component. To the best of our knowledge, this is the first published case of desmoplastic pigmented medulloblastoma, and the patient is the oldest reported to have this tumor.

Adult↗
PubMed2002

Chronic subdural haematoma and the enigmatic eosinophil.

The membranes from 50 cases of chronic subdural haematomas were examined histologically and correlated with the duration of the lesion. Cases were divided into three groups based on duration from time of trauma and/or onset of clinical symptoms to date of surgery - Group I: 1 to 30 days, Group II: 31 to 90 days and Group III: >90 days. Infiltration with eosinophils was observed in the vascularised and hyalinised granulation tissue of the subdural membrane in 30 of the 50 cases (60%). There was a trend to correlation both of the frequency and the extent of eosinophilic infiltration with duration of haematoma. Thus, eosinophils were encountered in about half the cases with duration up to 3 months which increased to 80% in cases with duration more than 3 months. The extent of eosinophilic infiltration (mild, moderate or severe) also appeared to correlate with duration of haematoma in that mild infiltration was more common in Group I cases while moderate to severe infiltration were more frequently observed in Group II and III cases. No correlation was observed of the eosinophilic infiltrate with age and sex of the patients or with presence of other cellular inflammatory components of the membrane. Interestingly, a finding hitherto unreported in English literature was the demonstration of mast cells in 7 of 16 membranes (44%) which had been stained using toluidine blue. It is possible that the eosinophils appear at this unusual site due to chemotactic stimulus abetted by these mast cells as well as lymphocytes and haemosiderin pigment. The eosinophils may have an important role in the repair and healing process of these membranes.

Adolescent↗
PubMed2002

Intramedullary tuberculoma of the spinal cord: a series of 10 cases.

OBJECTIVE: Involvement of vertebral column is common in tuberculosis but intramedullary tuberculomas are rare. We report a series of ten cases of intramedullary tuberculomas, which, to the best of our knowledge, is the largest series of biopsy proven intramedullary tuberculomas in English literature. METHODS: During a period of 16 years (1985-2000), ten cases of intramedullary tuberculomas were diagnosed in our department. Of these, eight cases were histologically proven intramedullary tuberculomas. The clinical profile, radiological data and histological slides were reviewed. RESULTS: Age ranged from 18 to 45 years (mean 29.7 years) and there was slight male preponderance (six men, four women). Duration of symptom varied from 3 to 20 months (mean 11.5 months). All of them presented with motor weakness and sensory impairment. Most common site of involvement was dorsal cord followed by cervical, cervicodorsal and dorsolumbar regions. Three patients had associated involvement of lungs, cervical lymphnodes, and brain, and one patient had past history of tuberculous meningitis. Two patients were treated conservatively but surgical excision was done in eight cases followed by medical treatment. CONCLUSION: Radiologically, intramedullary tuberculomas should be differentiated from other space occupying lesions (SOL) to avoid unnecessary surgery especially in those patients with tuberculosis of the other organs. The incidence of intramedullary tuberculomas is likely to increase with a rise in the incidence of AIDS.

Adolescent↗
PubMed2002

Brain biopsy in Creutzfeldt-Jakob disease: evolution of pathological changes by prion protein immunohistochemistry.

The formation of protease-resistant prion protein (PrPsc) is considered to be an early event in the pathogenesis of Creutzfeldt-Jakob disease (CJD) and hence its demonstration in brain biopsies by immunohistochemistry is considered diagnostic. We analysed eight brain biopsies from the frontal cortex collected from different parts of India from cases diagnosed as CJD on clinical and pathological grounds for the expression of prion protein (PrP). The duration of illness in these cases varied from 2 months to 1 year. Immunohistochemistry was carried out on paraffin sections using two different clones (KG9 and 3F4) of monoclonal antibodies to PrP. Although all eight cases showed classical features of spongiform encephalopathy of varying severity, only five of the eight cases revealed PrP(sc) in the brain tissue. The immunolabelling was focal and all areas with spongiform change were not labelled. A temporal evolution in the staining pattern was evident - particulate diffuse labelling (synaptic type) in early stages (2 months), perivacuolar deposits in intermediate stages (5-6 months), and dense plaques in late stages (12 months).

Adult↗
PubMed2002

Lipomedulloblastoma in a child: a controversial entity.

Lipomedulloblastoma is regarded as a distinct entity that occurs exclusively in adults and has a low proliferative potential and a favorable outcome. We describe a rare case of lipomedulloblastoma in a 6-year-old female child showing a high labeling index that needs documentation. The various hypotheses of adiposal change are discussed.

Adipose Tissue↗
PubMed2002

Recurrent astrocytic tumours--a study of p53 immunoreactivity and malignant progression.

Recurrence and progression to higher grade lesions are characteristic of the clinical course of astrocytic tumours. Though p53 gene mutation is an important initiating event in astrocytic tumourigenesis, its role in malignant progression remains controversial. We have therefore analysed p53 protein expression in paired histological samples from 48 cases of astrocytic tumours and their recurrences--29 diffuse astrocytoma, 10 anaplastic astrocytoma and 14 glioblastoma multiforme (GBM). Malignant progression at recurrence was noted in 93% of diffuse and 64% of anaplastic astrocytomas. An association was observed of p53 protein immunopositivity and malignant progression at recurrence. Thus, 27 of 48 (56%) primary tumours were initially p53 positive, while in recurrent tumours associated with malignant progression this frequency increased to 71% (34/48 cases). This was because seven of the 13 cases (4/8 diffuse and 3/5 anaplastic astrocytoma) that were initially p53 negative acquired immunopositivity on malignant progression at recurrence. In contrast, none of the 19 tumours that recurred to the same grade showed any change of p53 status at recurrence. Furthermore recurrence was associated with increase in the percentage of p53 immunopositive cells (p53 labelling index), which was also higher in tumours with progression. This new acquisition of p53 immunopositivity on progression at recurrence has not been documented in earlier studies in English language literature, though increase in p53 LI has been documented. Thus, this study conclusively indicates the role of p53 in malignant progression of astrocytic tumours. Also, it suggests a potential role of p53 LI in predicting malignant progression at recurrence because the highest initial LI was noted in those tumours which progressed to GBM as compared with those which recurred to the same grade or progressed to anaplastic astrocytoma. No correlation could, however, be demonstrated between p53 immunoreactivity and interval to recurrence.

Adolescent↗
PubMed2002

Microneural anastomosis with fibrin glue: an experimental study.

An experimental study was designed to compare the histological analysis of nerve anastomosis with 10-0 microsurgical sutures and fibrin adhesive. Wistar albino rats' sciatic nerves were transected and repaired either with fibrin adhesive-Beriplast P (M/s Centeon-Cadila Health Care) or with 10-0 monofilament microsutures. Histological assessment was performed at 10, 20, 30, 60 and 90 days after surgery. Functional recovery of the sciatic nerves started at two months and was near normal by three months. Separation of the stumps did not occur in any of the glued nerves. Histological evaluation showed no appreciable difference in the outcome of nerve regeneration after microsurgical repair using sutures or fibrin tissue adhesive. However, inflammation and granuloma formation were appreciated at the suture site, which presented a focal hindrance to myelin and axonal regeneration. Fibrin glueing is attractive for clinical purposes, since it is simpler and less time consuming than suturing.

Anastomosis, Surgical↗
PubMed2002

Antimicrobial drug use in dermatology in a teaching hospital in western Nepal.

Medical audit is supposed to oversee, monitor and analyse standards of medical treatment at all levels of the healthcare delivery system. This study was undertaken to monitor the prescribing of antimicrobial drugs for patients seeking treatment in the dermatology outpatient department of the Manipal Teaching Hospital in Nepal. A total of 292 dermatology prescriptions of patients attending the dermatology OPD were collected between July 2000 and June 2001. Prescriptions for antimicrobial agents were separated from the total prescriptions collected, and evaluated. There were more female patients (58.2%) than male (41.8%) in our study; most were in the 21-40 year age group. The commonest cutaneous infections were acne (15.8%) followed by fungal infections (14.8%). Of the 292 prescriptions audited, 149 contained antimicrobial agents, constituting 36% of the total number of drugs prescribed. Of 256 antimicrobials prescribed, 63% were topical and 37% systemic; 5% were generic, 29% were from the essential drug list of Nepal, and 15% were fixed-dose combinations. Most of the patients received one or two antimicrobials, 50% of which were antibacterials and 40% antifungals. Though the selection of antimicrobial drugs used in dermatology was largely rational, anomalies were observed, and these issues were discussed with clinicians in relation to various aspects of drug use. The results indicate there is scope for improving prescribing habits. A periodic audit of drug prescribing is desirable in rationalising prescribing practice.

Adult↗
PubMed2002

Osteochondroma of the spine: an enigmatic tumor of the spinal cord. A series of 10 cases.

BACKGROUND: The aim of this study was to evaluate clinical, radiological and pathological features of vertebral osteochondromas with compressive myelopathy and to review the relevant English literature. Osteochondro-mas are common benign bony lesions of long bones but involvement of spine by solitary osteochondroma and its presentation as compressive myelopathy is rare. Most of the literature is in the form of case reports. METHODS: During a period of 20 years (1980-1999), 10 cases of osteochondromas of the spine were encountered. Clinical, radiological and pathological features were reviewed. RESULTS: The age ranged from 13 to 45 years (mean 25.3 years) and all except 1 were males. In 8 cases the pathology involved the cervical spine and in two cases dorsal spine was involved. All patients presented with progressive motor sensory deficit of 6 months to 30 years duration (mean 3.9 years). Decompressive laminectomy was carried out in all the patients. Fortunately, gradual and complete recovery was observed in all of them. CONCLUSIONS: Osteochondromas of the spine are not as rare as reported in the literature. In a young patient of compressive myelopathy this possibility should be considered. Magnetic resonance imaging, computed tomography and CT myelogram are useful in evaluating the size and extent of the lesion for subsequent surgical planning.

Adolescent↗
PubMed2001

Alteration of a sequence with homology to human endogenous retrovirus (HERV-K) in primary human glioma: implications for viral repeat mediated rearrangement.

We had earlier demonstrated that a comparison of DNA fingerprinting profiles of tumor and corresponding normal DNA from the same patient by random amplified polymorphic DNA (RAPD) analysis can readily demonstrate alterations in tumor DNA [Gene 206 (1998) 45 and J. Neuro Oncol. 48 (2000) 1]. These alterations could be used to identify changes in tumor DNA where the prior identity of the locus was not known. In this study, we report the identification, cloning and characterization of a RAPD amplified fragment which was lost in a glioma, a grade IV glioblastoma multiforme (GBM). Comparison of the RAPD profile of tumor and corresponding leucocyte DNA revealed several differences between the two. These included a band of 443 bases, which was demonstrated in the normal, but not in tumor DNA. On sequencing, this band was found to be homologous with a group of SINE sequences, which are probably derived from the human endogenous retrovirus-K (HERV-K). Homology search also reveals that HERV-K-derived sequences are interspersed, amongst others, in the tumor suppressor gene BRCA2 and the DNA repair gene XRCC1. Of particular interest is the inverted repeat pattern of HERV-derived sequences in the genes. While not demonstrating a cause effect relationship, this highlights the possible role of such virus-derived sequences in gene inactivation by recombination during tumorigenesis.

Base Sequence↗
PubMed2001

Diastematomyelia associated with ectopic dysplastic renal tissue--report of a rare case.

BACKGROUND: Presence of heterotopic dysplastic renal tissue in the lumbosacral region is an extremely uncommon condition. CASE REPORT: We report the first case of diastematomyelia associated with ectopic renal tissue. A 10-month-old male child presented with lipomeningomyelocele associated with spina bifida in the lumbosacral region, and the lipoma was excised. Imaging of the spine at 5 years of age showed spina bifida, bony diastematomyelia, lipomeningomyelocele and a small intraspinal cystic lesion. The boy was then operated upon at the age of 5 years, and histopathological examination of the cystic lesion revealed ectopic dysplastic renal tissue.

Choristoma↗
PubMed2001

Clinicopathological features, MIB-1 labeling index and apoptotic index in recurrent astrocytic tumors.

This is a study of 64 cases of recurrent astrocytic tumors of all four WHO grades wherein a comparative evaluation of initial vs. recurrent tumor was done with respect to histological grading, MIB-1 labeling index (LI) and apoptotic index (AI). The aim was to identify factor/s that could influence interval to recurrence and/or malignant progression. Recurrence was noted in all grades and upon recurrence, 93.3% of grade II (low grade diffuse) astrocytomas and 63.6% of grade III anaplastic astrocytomas underwent malignant progression. However, none of the Grade I tumors showed evidence of malignant progression. Though interval to recurrence varied considerably, there was a correlation with histological grade of the initial tumor in that grade I and II tumors had a significantly longer mean interval to recurrence (43 months and 54.8 months respectively) as compared to grade III and IV (glioblastoma multiforme) tumors (17.6 and 12.8 months respectively). The interval to recurrence was also longer for grade II and III tumors which showed progression on recurrence (55.3 months for Grade II->Grade III; 54 months for Grade II->Grade IV and 20.6 months for Grade III->IV) as compared to tumors which recurred to the same grade (12.5 months for Grade III->Grade III and 12.8 months for Grade IV->Grade IV). A statistically significant inverse correlation of MIB-1 LI with interval to recurrence was noted. Higher the MIB-1 LI, shorter was the interval to recurrence. Further a cut off MIB-1 LI value of 2.8% could be proposed in predicting recurrence free survival. Interestingly, MIB-1 LI of grade II tumors, which had progressed to grade IV was significantly higher than MIB-1 LI of grade II tumors which had progressed to grade III. Thus, this study establishes the potential role of MIB-1 LI of the initial tumor in determining interval to recurrence. However, apoptotic index has no role in predicting either interval to recurrence or malignant progression.

Adolescent↗