The use of lung dose-volume histograms in predicting post-radiation pneumonitis after non-conventionally fractionated radiotherapy for thoracic carcinoma.

AIMS: To assess the use of lung dose-volume histogram (DVH) parameters (specifically V20Gy) in the prediction of radiation pneumonitis for non-conventional fraction sizes used in the treatment of lung cancer. MATERIALS AND METHODS: Patients requiring computed tomography planning for thoracic radiotherapy between January 1999 and January 2002 were identified. The patients receiving radical or high-dose palliative radiotherapy had DVH produced routinely during planning. These were retrospectively reviewed and the case notes accessed for additional pre-treatment parameters, demographics and evidence of radiation pneumonitis. The severity of the pneumonitis was then scored using Radiation Therapy Oncology Group criteria. Data were analysed using the SPSS computer program. RESULTS: One hundred and sixty consecutive patients were reviewed. Ninety patients received hypofractionated treatment (fraction size > 2.5 Gy) and 57 continuous hyperfractionated accelerated radiation therapy (CHART) (fraction size 1.5 Gy). Lung V20Gy values ranged from 3% to 53%, with a median value of 24%. Only six patients reported grade 2, and 16 patients grade 3 pneumonitis. Two patients developed fatal, grade 5 pneumonitis. No correlation between pneumonitis score and V20Gy or other possible predictive factors was found. CONCLUSION: The 15% grade 2-5 pneumonitis rate we document is at the lower end of the spectrum reported in other studies. This suggests that using published data on limiting V20Gy values to reduce the risk of radiation pneumonitis can be extrapolated to planning treatment with non-conventionally fractionated radiotherapy.

Retrospective audit of the value of the pancreolauryl test in a district general hospital.

OBJECTIVES: To audit the specificity and value of the pancreolauryl test (PLT) for the diagnosis of pancreatic insufficiency. DESIGN: A retrospective case note review of 47 patients who had a PLT during three consecutive years. SETTING: A 650 bedded district general hospital. MAIN OUTCOME MEASURES: Patient demographics, symptoms, baseline blood, endoscopic and radiological investigations, and alcohol consumption were related to the results of the PLT to determine if the test could be better targeted. Response to therapy and final diagnoses were noted to determine the specificity of the test. RESULTS: Forty seven patients had a PLT during the three years studied. All successfully performed the test as outpatients. Seven inconclusive tests were repeated. Thirty eight patients (81%) had diarrhoea, of whom 10 (21%) described steatorrhoea; 23 (49%) had an abnormal PLT. All with an abnormal test had diarrhoea, more frequently describing watery stools than steatorrhoea. Those treated with pancreatic enzyme supplements had an excellent response, although two of these had a final diagnosis of coeliac disease. Nineteen patients with an abnormal PLT were thought to be suffering from pancreatic insufficiency. All patients with a normal PLT were clinically thought not to have pancreatic insufficiency. Age, sex, and alcohol intake correlated poorly with final diagnosis. CONCLUSIONS: The PLT can be used in a district general hospital setting as an outpatient test for pancreatic insufficiency and has a specificity of 83%-91%. Its use should be restricted to those presenting with diarrhoea, not necessarily steatorrhoea, and not restricted to those with a history of high alcohol consumption.