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Precise calculations of the total Rayleigh-scattering optical depth have been performed at 88 wavelengths ranging from 0.20 to 4.00 microm for the six well-known standard atmosphere models by integrating the volume Rayleigh-scattering coefficient along the vertical atmospheric path from sea level to a 120-km height. The coefficient was determined by use of an improved algorithm based on the Ciddor algorithm [Appl. Opt. 35, 1566 (1996)], extended by us over the 0.20-0.23-microm wavelength range to evaluate the moist air refractive index as a function of wavelength, air pressure, temperature, water-vapor partial pressure, and CO2 volume concentration. The King depolarization factor was also defined taking into account the moisture conditions of air. The results indicate that the influence of water vapor on Rayleigh scattering cannot be neglected at tropospheric altitudes: for standard atmospheric conditions represented in terms of the U.S. Standard Atmosphere (1976) model, the relative variations produced by water vapor in the Rayleigh scattering parameters at a 0.50-microm wavelength turn out to be equal to -0.10% in the moist air refractivity at sea level (where the water-vapor partial pressure is equal to approximately 7.8 hPa), -0.04% in the sea-level King factor, -0.24% in the sea-level Rayleigh-scattering cross section, and -0.06% in the Rayleigh-scattering optical depth.

Background and Purpose: The European Society for Therapeutic Radiology and Oncology was funded by the EU for a project on recording providing education, and ameliorating the consequences of treatment (REACT). An European audit was carried out as part of which to assess the usefulness of current follow-up practices., Patients and Methods: Over a 4-month period in 15 cancer centres in 10 countries, patients attending for routine follow-up completed a questionnaire covering their expectations of and satisfaction with the visit. This was matched with a questionnaire completed by the physician about the content and usefulness of the consultation. The feasibility of a short toxicity scale developed by Dische and Saunders was also investigated., Results: In total, 2303 matched questionnaires were analysed. Forty percent of the patients had symptoms or medical problems related to their disease. In 18% there was a positive finding on clinical examination. In 28% investigations were undertaken part of departmental routine practice. Ten percent of the investigations showed an abnormal result. Ninety nine percent of physicians and 85% of the patients expressed satisfaction. Using the short toxicity scale rates of recording toxicity could be increased from 28 to 93%., Conclusions: There is wide variation in follow-up practices among European centres. There was a low incidence of positive findings clinically or with routine investigations. A simple scale for recording morbidity has proved easy to use by departments, which have not routinely used one of the standard measures. Further work will attempt to produce an European guideline for effective routine follow-up after radiotherapy.

Purpose: To assess whether the topical use of steroids or 5-aminosalicylic acid (5-ASA) is superior to sucralfate in preventing acute rectal toxicity during three-dimensional conformal radiotherapy (3DCRT) to 76 Gy., Patients and Methods: Patients undergoing 3DCRT for prostate carcinoma at our institution were offered to be randomized to sucralfate 3 g in 15 ml suspension enema (Antepsin, mesalazine 4 g gel enema (Enterasyn, or hydrocortisone 100 mg foam enema (Colifoam. Randomization was blind to the treating physician but not to the patient. Sucralfate was chosen as control arm. Topical treatment had to be performed once daily, starting on day 1 of 3DCRT. Acute rectal toxicity was scored weekly according to RTOG criteria. Time to occurrence of grade 2+ acute rectal toxicity was taken as endpoint., Results: The trial was opened in August 1999, and after the first 24 patients had been treated, arm 2 was discontinued because of eight patients receiving mesalazine, seven actually developed acute rectal toxicity (five patients grade 3 and two patients grade 2). Until May 2001, 134 consecutive patients were randomly assigned to sucralfate (63 patients), mesalazine (eight patients) or hydrocortisone (63 patients). The cumulative incidence of acute rectal toxicity at the end of treatment by arm is 61.9 +/- 6.1%, 87.5 +/- 11.7%, and 52.4 +/- 6.2% for arms 1, 2, and 3, respectively. The difference between the mesalazine group and the sucralfate group is highly significant (hazard ratio [HR] 2.5, 95% confidence interval [CI] 1.1-5.7; p = 0.03). At both uni- and multivariate analysis taking into account several patients and treatment covariates, the difference between hydrocortisone and sucralfate is not significant (HR 0.7, 95% CI 0.5-1.2; p = 0.2)., Conclusion: Topical mesalazine is contraindicated during radiotherapy. Hydrocortisone enema is not superior to sucralfate in preventing acute rectal toxicity.