Quantities and costs were not reported separately. The estimation of costs was based on actual data based on the 53 patients recruited prospectively between September 1996 and March 1997. Procedural costs were calculated for endoscopic, radiotherapeutic and surgical interventions (accounting for staff and equipment costs in each case) as well as the cost of outpatient, inpatient and intensive care unit episodes. Staff costs were calculated by recording the staff requirements (including grade of staff) for, and the duration of, a given procedure. In determining equipment costs, the current purchase cost, nature of guarantee, service contract and life span were identified. Incremental surcharges were employed to account for intangible costs such as heating, lighting, building maintenance and administration. Costs do not appear to have been discounted, although, for some of the patients, they were incurred during a period of 3 years.