Patterns of care for malignant pleural mesothelioma patients compensated by the Dust Diseases Board in New South Wales, Australia.

BACKGROUND: The silent epidemic of mesothelioma in Australia is steadily increasing, and 30% of cases occur in New South Wales (NSW). AIM: To describe the patterns of care and outcomes of patients with malignant pleural mesothelioma (MPM) in NSW. METHODS: MPM patients in NSW applying for compensation at the NSW Dust Diseases Board from 2007 to 2009 were included. Survival from time of diagnosis was determined by the Kaplan-Meier method. The Chi-squared test was used to determine if there was an association between utilisation of treatment and geographical location. RESULTS: A total of 138 patients was included: median age was 72.5; 91.3% male; 60.1% epithelial subtype; and 65.2% lived in major cities. All patients had at least one chest X-ray and computed tomography scan, and 21% had a positron emission tomography scan; 93.5% and 4.3% had histological or cytological confirmation respectively. Thoracoscopy (59.4%) was the most commonly used diagnostic procedure. Treatment utilisation: 53.6% chemotherapy; 35.5% radiotherapy; 9.4% extrapleural pneumonectomy (EPP); and 72.5% had palliative care involvement. There were no major differences in treatment utilisation between patients living in major cities and those in regional NSW (chemotherapy P = 0.42; radiotherapy P = 0.13 and palliative care P = 0.60), except for a higher rate of EPP in regional patients (16.7% vs 5.6%; P = 0.03). Median survival was 9.7 versus 12.3 months for city and regional patients respectively (P = 0.22). CONCLUSION: Survival and treatment utilisation was not significantly different between MPM patients living in major cities and regional NSW, except for a higher rate of EPP in patients in regional NSW.

Phase II trial of carboplatin in the management of malignant mesothelioma.

Thirty-one patients with advanced malignant mesothelioma, previously untreated or having received only one prior cytotoxic regimen, were treated in a prospective, single-arm phase II trial with carboplatin (NSC 241240) at a dose of 150 mg/m2 per day intravenously (IV) for 3 days (450 mg/m2/course). One complete remission and four partial remissions were achieved, yielding an overall objective response rate of 16% (95% confidence interval [CI], 5.4% to 34%). The median duration of remission was 8 months (range, 5 to 17). Nonhematological toxicity was mild (only 12% with World Health Organization [WHO] grade 3 vomiting); 16% suffered WHO grade 3 to 4 hematological toxicity, but there were no life-threatening episodes and no treatment-related deaths. Carboplatin has modest activity against malignant mesothelioma and, because of its low toxicity, has a role in the management of this disease.

Ventilation-perfusion relationships in symptomatic asthma. Response to oxygen and clemastine.

Continuous distributions of ventilation-perfusion (VA/Q) ratios were measured in ten subjects with moderately severe symptomatic asthma. Six of the subjects had only minimal VA/Q inequality (mean log SD of bloodflow 0.5) despite having airways obstruction similar to that in the four subjects with marked VA/Q inequality (mean log SD of bloodflow 1.0). The six patients with minimal VA/Q inequality developed marked widening of their VA/Q distributions while breathing 100 percent oxygen (mean log SD bloodflow 1.1), and four of these patients maintained more modest widening after receiving an intravenous antihistamine, clemastine (mean log SD bloodflow 0.75). The four subjects with a wide control VA/Q distribution showed smaller changes while breathing pure oxygen and no change after receiving clemastine. FEV1 improved with clemastine treatment in the first four patients only. The results suggest that the majority of patients with moderately severe asthma have compensatory pulmonary vasoconstriction, causing better VA/Q matching which is responsive to hypoxia and, possibly, histamine. The data demonstrate a relationship between active compensatory vasoconstriction and airway sensitivity to antihistamine.

Pattern and time course of ventilation-perfusion inequality in exercise-induced asthma.

The relation between exercise-induced airway obstruction and changes in the gas exchange function of the lung was studied in 6 subjects with asthma. Continuous distributions of ventilation perfusion (VA/Q) ratios and spirometry were measured before and at intervals after an exercise challenge that caused a greater than 20% decrease in FEV1 or in peak expiratory flow rate (PEFR). Before exercise, all subjects had unimodal VA/Q distributions that were broader than normal (mean log SD of blood flow, 0.54) and all developed wider distributions 15 to 28 min after the start of the 8-min exercise challenge (mean log SD of blood flow, 1.02). Two subjects developed bimodal VA/Q distributions, but all distributions returned to baseline configuration within 58 min, usually before FEV1 and PEFR had returned to baseline values. There was no relation between the decrease in FEV1 or PEFR and the degree of VA/Q inequality. Aerosolized salbutamol resulted in improved spirometry and further narrowing of the VA/Q distributions in 3 subjects tested.

Arrhythmias in two patients with left ventricular bypass transplants.

Two patients who underwent left ventricular bypass transplants are described. Both patients sustained postoperative rhythm disturbances of their own hearts during sinus rhythm of the donor hearts. Illustrative examples of atrial flutter, ventricular flutter, ventricular fibrillation, blocked atrial extrasystoles, and double ventricular parasystole in the recipient hearts are presented. The patients tolerated all these arrhythmias well during uninterrupted sinus rhythm in the donor heart. The problems in interpretation of arrhythmias in the presence of two hearts are discussed.