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Biomedical subjects

B Rajan

Publications and source records attributed to B Rajan.

36 records · Page 2Linked to original sources
PubMed1996

Detection of HIV infection in pulmonary tuberculosis patients.

Well documented 112 pulmonary tuberculosis patients were studied for the prevalence of human immunodeficiency virus (HIV) seropositivity by using two antibody screening tests along with western blot test. Nineteen of the pulmonary tuberculosis patients were HIV seropositive, 12 were acid-fast bacillus smear positive; 12 patients were tuberculin skin test positive and 15 patients were culture positive. As the incidence of HIV infection is increasing in India, it is observed that patients co-infected with HIV and TB are also on the rise. Recognition of the dual infection and taking adequate steps to deal with this epidemic are needed.

AIDS-Related Opportunistic Infections↗
PubMed1995

Case report: brain metastases from papillary carcinoma thyroid.

Papillary carcinoma, the commonest thyroid malignancy, has a good prognosis and low incidence of distant metastases. Brain metastasis is extremely rare with a frequency of 0.1-5% in reported series. The clinical details of two cases of histologically proven brain metastases from papillary thyroid cancer treated in our centre are presented. In one patient, the lesion was in the cerebellar hemisphere, and in the other, the frontal lobe. Also presented is a review of the literature of this unusual clinical presentation.

Brain Neoplasms↗
PubMed1995

Case report: spinal metastasis from carcinoma of the penis.

Carcinoma of the penis has a well documented metastatic pattern, regional lymph nodes being the predominant site of involvement. Distant metastasis is extremely rare, with a reported incidence of 1-10%. Osseous metastasis is even rarer and no case of metastasis to the spine has been reported previously. We present a case of carcinoma of the penis metastasizing to the spine.

Humans↗
PubMed1994

The management of histologically unverified presumed cerebral gliomas with radiotherapy.

PURPOSE: To define the natural history, and prognostic factors of patients with histologically unverified presumed gliomas diagnosed on CT or MR imaging, and treated with external beam radiotherapy. METHODS AND MATERIALS: Retrospective review of 111 adults with histologically unverified presumed cerebral glioma treated with radiotherapy between 1974 and 1990. Using CT or MRI criteria alone 41 were presumed low grade, 63 high grade gliomas and 7 were unclassified. Survival results were compared to a cohort of 82 adults with histologically verified low grade gliomas treated over the same period with surgery and radiotherapy. RESULTS: The 5 year survival probability of the whole cohort was 31%. Age, performance status, and the degree of contrast enhancement were independent prognostic factors for survival. Patients with presumed low grade glioma had a 5 year survival of 41% compared to 52% for patients with verified low grade glioma. After correction for prognostic factors no significant difference was found in the survival between patients with verified and unverified low grade tumors. One of 15 cases with subsequent histology, obtained at autopsy or salvage surgery, had nonglial pathology. CONCLUSION: Patients diagnosed on the basis of clinical features and imaging as having presumed glioma have similar natural history and clinical behavior after treatment with radiotherapy to those with histologically confirmed gliomas. However, the results should not be taken as justification for avoiding biopsy. A proportion of patients may have nonglial pathology and new more effective treatment strategies for patients with glial tumors can only evolve on the basis of full diagnostic information including pathology.

Adolescent↗
PubMed1994

Survival in patients with recurrent glioma as a measure of treatment efficacy: prognostic factors following nitrosourea chemotherapy.

The assessment of efficacy of treatment in patients with recurrent glioma is notoriously difficult, and survival is the most objective endpoint. Between 1970 and 1992, a cohort of 211 patients with recurrent glioma received nitrosourea-based chemotherapy at the time of disease progression. The median survival from the start of chemotherapy was 7 months, with 30% 1-year and 10% 2-year survival probabilities. One-year survival was 22% in 147 patients with recurrent high-grade astrocytoma, 41% in 37 patients with low-grade astrocytoma and 45% in 24 patients with oligodendroglioma. Age, histological grade and Karnofsky performance status (KPS) at recurrence were independent prognostic factors for survival on multivariate analysis. Based on patients' age, tumour grade and KPS, it was possible to define three distinct prognostic groups with 1-year survival probabilities of 60, 21 and 17% (P < 0.005). Response to chemotherapy was difficult to assess but correlated with prognostic subgroup, with highest response rate (46%) in the most favourable group and lowest (13%) in the poor prognostic group. In patients with recurrent glioma, patient and tumour parameters are the major determinants of outcome which are identical to prognostic factors at the time of primary diagnosis. They can be used to provide prognostic information for the individual patient, and to stratify patients particularly in trials assessing the efficacy of novel treatments.

Adolescent↗
PubMed1993

Craniopharyngioma--a long-term results following limited surgery and radiotherapy.

Between 1950 and 1986 173 patients with craniopharyngioma were treated at the Royal Marsden Hospital with external beam radiotherapy either alone or following surgery. Four patients had complete tumour excision, 21 subtotal and 78 partial resection, 14 had biopsy alone, 34 aspiration alone and 22 had no surgery directed at tumour eradication. Seventy-seven (45%) were children (aged < 16 years). The 10 and 20 year progression-free survival (PFS) rates were 83% and 79%. There were no independent prognostic factors for PFS. The 10 and 20 year survival rates were 77% and 66% at a median follow-up of 12 years. After adjustment for mortality in the normal population, age and technique of radiotherapy (which corresponded with era of treatment) were significant independent prognostic factors for survival. The risk of death (corrected for mortality from natural causes and controlling for radiotherapy technique) for age groups 16-39 and > or = 40 was 0.58 and 0.40 respectively, relative to a risk of 1.0 for the age group < 16 years. Survival and PFS were not influenced by the extent of surgical excision. Visual field defect improved after radiotherapy in 36% of patients (38/106) and visual acuity in 30% (27/91). No patient developed radiation optic neuropathy. We conclude that limited surgery and radiotherapy achieve excellent long-term tumour control and survival with low morbidity.

Adolescent↗
PubMed1993

The long-term efficacy of conservative surgery and radiotherapy in the control of pituitary adenomas.

OBJECTIVES: We assessed the long-term efficacy and toxicity of conservative surgery and radiotherapy in the control of pituitary adenomas. DESIGN: Retrospective study of patients treated at the Royal Marsden Hospital. PATIENTS: Four hundred and eleven patients with pituitary adenomas treated with conventional external beam radiotherapy at the Royal Marsden Hospital between 1962 and 1986. Two hundred and fifty-two patients had clinically non-functioning pituitary adenomas, 131 had hormone secreting tumours and in 28 patients the secretory status was not known. Three hundred and thirty-eight patients had surgical intervention of whom only 11 had complete tumour excision. All patients received conventional fractionated external beam radiotherapy to a dose of 45-50Gy in 25-30 fractions. MEASUREMENTS: Actuarial progression free survival and overall survival and assessment of toxicity, particularly in terms of vision, requirement for hormone replacement therapy and incidence of second tumours. RESULTS: The actuarial progression free survival was 94% at 10 years and 88% at 20 years for all patients and 97% at 10 years and 92% at 20 years for patients with clinically non-functioning adenomas. Only secretory status was an independent prognostic factor for disease control. The 10 and 20-year survivals for all patients were 77 and 58% respectively. When compared with the normal population the relative risk of death was 1.76 (P < 0.001) and no prognostic factors for survival were identified. The morbidity of radiotherapy was low. Visual deterioration, assumed to be radiation induced, occurred in 1.5% of patients and the risk of second brain tumour was 1.9% at 20 years. Fifty per cent of patients received hormone replacement therapy by 19 years. CONCLUSION: Conventional external beam radiotherapy as described here combined with conservative surgery is safe and effective in the control of pituitary adenomas. These results should form a baseline for comparison with new treatment strategies.

Adenoma↗
PubMed1992

Risk of second brain tumour after conservative surgery and radiotherapy for pituitary adenoma.

OBJECTIVE: To assess the risk of second brain tumour in patients with pituitary adenoma treated with conservative surgery and external beam radiotherapy. DESIGN: Long term follow up of a cohort of patients with pituitary adenoma and comparison of tumour occurrence with population incidence rates. SETTING: The Royal Marsden Hospital. SUBJECTS: 334 patients with pituitary adenoma treated with conservative surgery and radiotherapy (median dose 45 Gy) and followed up for 3760 person years. MAIN OUTCOME MEASURES: Second intracranial tumour and systemic malignancy. RESULTS: Five patients developed a second brain tumour: two had astrocytoma, two meningioma, and one meningeal sarcoma. The cumulative risk of developing a second brain tumour over the first 10 years after treatment was 1.3% (95% confidence interval 0.4% to 3.9%) and over 20 years 1.9% (0.7% to 5.0%). The relative risk of a second brain tumour compared with the incidence in the normal population was 9.38 (3.05 to 21.89). There was no excess risk of any other type of second primary malignancy. CONCLUSIONS: There is an increased risk of second intracranial tumour in patients with pituitary adenoma treated with surgery and radiotherapy. Although radiation is likely to be the most important factor contributing to the excess risk, further study is required in a cohort of similar patients not receiving radiation.

Adenoma↗
PubMed1992

Selective avoidance of lymphatic radiotherapy in the conservative management of early breast cancer.

In view of the morbidity and potential mortality associated with routine post-operative lymph node radiotherapy in women with early stage breast cancer, an attempt has been made to select patients in whom radiotherapy can be withheld. Three hundred and forty-seven consecutive patients treated wide local excision plus or minus axillary surgery have been evaluated. Only 20% were subsequently given radiotherapy to regional nodes. Relapse in the axilla, the supraclavicular fossa or at both these sites have occurred in 16 patients so far, 12 of whom were successfully treated. Systemic relapse was seen in eight of these patients occurring with one exception before or within 3 months of node relapse. Only four have persisting symptoms as a result of nodal relapse. So far, a policy involving selective lymphatic radiotherapy in women treated for early breast cancer appears justified.

Axilla↗
PubMed1992

Radiotherapy for the treatment of recurrent craniopharyngioma.

Twenty-five patients with craniopharyngioma received radiotherapy at the time of recurrence. The 10-year progression free survival and survival from the time of recurrence were 72% and 77% respectively. Nineteen patients underwent surgery prior to radiotherapy (6 partial excision, 4 decompression and 9 cyst aspiration). The extent of resection at the time of recurrence did not influence the outcome. Apart from pituitary failure there was no serious morbidity associated with this approach. The results of radiotherapy at recurrence are similar to those of conservative surgery and radiotherapy at the time of presentation. It suggests that radiotherapy remains an effective treatment modality at the time of recurrence of craniopharyngioma and it may therefore be delayed in situations where immediate radiation is not advisable. However, the high recurrence rate in incompletely excised craniopharyngioma, together with the potential risk of additional morbidity and mortality from undiagnosed progressive tumour and salvage surgery, would argue for a policy of radiotherapy as part of the initial treatment of incompletely excised craniopharyngioma.

Adolescent↗
PubMedDate not supplied

Malignant phyllodes tumor.

The study aims to evaluate the survival and prognosis of patients with malignant phyllodes tumor. Between 1982 and 1998, 37 women with malignant phyllodes tumor were treated at the Regional Cancer Center, Trivandrum. Twelve patients were recurrent. Survival was estimated using the Kaplan-Meier method. Patient, disease, and treatment factors were compared using log-rank test. The Cox-proportional hazard model was employed to identify the prognostic factors. Thirty-six patients had surgery. Twenty-five patients received postoperative radiotherapy, and 2 received chemotherapy in addition. The median follow-up was 43 months (range 1-170 months). Eight patients failed locally, and 7 of these were successfully salvaged by surgery. The 5-year overall survival was 74.2% (95% CI, 0.44 to 0.89), whereas 5-year disease-free survival was 59.6% (95% CI, 0.39 to 0.7). The margin of surgical excision was found to be the only independent prognostic factor (p=0.003). However, patients with tumor size more than 5 cm (hazard ratio 2.9) were found to have increased hazard, whereas those receiving adjuvant radiotherapy (hazard ratio 0.6), married women (hazard ratio 0.4), and those women over the age of 35 years (hazard ratio 0.7) showed a decreased hazards. Cystosarcoma phyllodes is a rare malignancy of the female breast. Surgery with adequate margins is the primary treatment. Adjuvant radiotherapy appears to improve the disease-free survival.

Adult↗
PubMedDate not supplied

Testicular germ cell tumors in prepubertal children.

Pediatric testicular germ cell tumors are rare. Fifteen children, all less than 5 years of age, were evaluated and treated during February 1987 to July 1996. The median age was 18 months (range, 4-60 months). All were staged according to the Pediatric Oncology Group/Children's Cancer Study Group staging system. Seven patients had stage III disease. Histologically, 9 patients had pure endodermal sinus tumor, 1 had endodermal sinus tumor with embryonal carcinoma, 1 had embryonal carcinoma alone, 2 had immature teratoma, and 2 had mature teratoma. Six children were kept on surveillance. All others received chemotherapy with cisplatin, bleomycin, and vinblastine. The 10-year actuarial overall survival rate was 86.7%.

Antineoplastic Combined Chemotherapy Protocols↗
PubMedDate not supplied

Air movement visualization in the workplace: current methods and new approaches.

Airflow visualization in the workplace to assess containment, ventilation, or general air movements is often carried out using smoke tracers. The most prevalent method uses a disposable smoke tube that generates a plume of concentrated sulfuric acid fume. However, use of the smoke tube exposes occupational hygienists to the risk of sulfuric acid exposure through inhalation or dermal contact, as well as injury from sharps. Following concern over the potential health hazard associated with smoke tube usage, alternative flow visualization methods and technologies have been reviewed. Methods of generating smoke or bubbles other than using smoke tubes suitable for visualizing air movements include heated element smoke generators, combustion generators, generation of metallic chlorides and ammonium chloride, generation of neutral density bubbles, and water fog generation. Some of these methods are applicable in specific workplace situations. However, there is no commercially available smoke or bubble generator currently available that matches the smoke tube for cost effectiveness, ease of use, and wide applicability, while also reducing the potential health risks associated with smoke tube usage. Despite this, certain technologies, in particular water/glycerol smoke generation using heated element generators, have the potential to be developed into viable alternatives to the smoke tube. Thus, with further development, an air movement visualization method that poses a significantly lower health hazard than the smoke tube is feasible.

Aerosols↗