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Vedang Murthy

Publications and source records attributed to Vedang Murthy.

6 recordsLinked to original sources

Recovery of serum testosterone after neoadjuvant androgen deprivation therapy and radical radiotherapy in localized prostate cancer.

OBJECTIVE: To prospectively evaluate the time-course of recovery of serum testosterone levels after a short course of luteinizing hormone-releasing hormone analogue (LHRHa) and radical radiotherapy to the prostate. PATIENTS AND METHODS: Testosterone, luteinizing hormone (LH) and follicle-stimulating hormone (FSH) were sequentially measured prospectively in 59 men who received short-course LHRHa treatment and radiotherapy for localized prostate cancer. Measurements were made before treatment (baseline), during LHRHa treatment, and at 6, 12, 18, 24 and >40 weeks after the last LHRHa injection. RESULTS: The median (range) time from the first to last LHRHa injection was 116 (54-194) days. The mean (95% confidence interval) testosterone levels (in nmol/L) at baseline, during treatment and at 6, 12, 18, 24 and >40 weeks afterward were 12.0 (10.8-13.1), 0.6 (0.5-0.7), 1.4 (0.6-2.2), 11.4 (9.7-13), 12.2 (10.5-14), 10.4 (8.9-12) and 11.7 (10.5-13). Four men had low baseline testosterone levels (<6.1 nmol/L). At 6 weeks after the last LHRHa injection, no men had testosterone levels in the 'normal' range; 35% were in the normal range at 12 weeks, 85% at 18 weeks, 89% at 24 weeks, and 96% at 1 year. CONCLUSION: After LHRHa treatment and radiotherapy, the testosterone levels of most men had recovered to normal by 18-24 weeks after the last LHRHa injection.

Aged↗

Stereotactic conformal radiotherapy for posterior fossa tumours: a modelling study for potential improvement in therapeutic ratio.

PURPOSE: To investigate the optimal technique of stereotactic conformal radiotherapy (SCRT) for posterior fossa tumours. MATERIAL AND METHODS: SCRT planning image data sets of four patients with posterior fossa tumours constituted the study material. Based on the operative notes and preoperative imaging, a clinical target volume (CTV) was drawn for each patient. An additional CTV representative of a typical posterior fossa tumour was also drawn on each patient's localisation scans. Therefore a total of eight CTVs differing in their size and location were used for further work. A margin of 5 mm was grown in three dimensions to result in a final planning target volume (PTV). Beam arrangements studied were conformal bilateral parallel pair, a three-field coplanar arrangement with two bilateral and a vertex beam, two three-field non-coplanar techniques and a six-field non-coplanar technique with conformation achieved by micromultileaf collimator (mMLC). Normal structures contoured included normal posterior fossa brain (excluding PTV), brain stem, cochleae, optic apparatus, pituitary-hypothalamic axis (PHA), supratentorial brain and the temporal lobes. Comparative evaluation of plans was done with dose volume histograms (DVH), conformity index (CI) and dose heterogeneity (DH). RESULTS: In all plans, the 95% isodose line covered at least 99% of the PTV with acceptable dose heterogeneity. As compared to the baseline bilateral conformal parallel pair plan, all other plans achieved significantly more sparing of the normal posterior fossa brain at the 95 and 80% dose prescription levels with superior CI (at 95% isodose). The six-field technique resulted in maximum sparing as compared to the bilateral plan with a mean additional sparing of 74% (46.2 cm3) and 55% (33.83) at 95 and 80% dose prescription level, respectively (P<0.0001). Among the three field plans, the technique of bilateral and vertex fields resulted in least doses to cochlea and also irradiated the least volume of brain stem and PHA. Comparison of this technique to the six-field technique did not show any significant difference in sparing of normal structures in the posteriorly placed tumours. In anteriorly placed tumours, the six-field technique was the most optimal irrespective of the size of the target volumes. CONCLUSIONS: A six-field plan SCRT achieves the most significant sparing of the normal tissues for localised irradiation in posterior fossa tumours, particularly for anteriorly located tumours. A relatively simpler three-field plan with bilateral and a vertex beam is equally good for tumours that are placed posteriorly and away from the brain stem.

Child↗

Medical decompressive therapy for primary and metastatic intracranial tumours.

Medical decompressive therapy (MDT) with corticosteroids and mannitol is often used in patients with primary or metastatic brain tumours. This review highlights the lack of sound evidence regarding the indications and dosage schedule of steroids, prolonged use of which may cause debilitating complications. The available evidence supports the short-term use of MDT for raised intracranial pressure or progressive neurological deficits, but in the absence of these symptoms, MDT is not recommended for stable focal deficits, abnormal higher mental functions, seizures, or as prophylaxis during cranial irradiation. A practical stepladder guideline (based on symptom severity) is proposed with a starting daily dexamethasone dose of 6 mg for non-severe headache and or vomiting; 12 mg for progressive focal neurological deficit with or without non-severe headache or vomiting; and 24 mg dexamethasone with mannitol for severe headache, vomiting, or altered consciousness. Depending on the clinical response, dose can be increased to the next step(s) or tapered every 48 h (more slowly in patients who are dependent on steroids). A scheme for the assessment of efficacy and toxicity prevention is also proposed. The proposed guidelines may be used as a template for further clinical research.

Adrenal Cortex Hormones↗

Solitary extramedullary plasmacytoma of the premaxilla.

Solitary extramedullary plasmacytoma is a rare tumour with radiotherapy playing an important role in its management. This report describes the case history of a man with a solitary extramedullary plasmacytoma at an extremely rare site, the premaxilla, that posed certain diagnostic and therapeutic dilemmas. The patient underwent surgery followed by postoperative radiotherapy. The use of two modalities of treatment for this localized tumour has been justified by briefly reviewing the literature and defining the various prognostic factors. These prognostic factors in turn should guide the treatment of these uncommon tumours.

Combined Modality Therapy↗