Setting Hospital. The study was carried out at Duke University Medical Center, Durham, North Carolina, USA.

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1 Cost-effectiveness of treatment of early stage endometrial cancer Ashih H, Gustilo-Ashby T, Myers E R, Andrews J, Clarke-Pearson D L, Berry D, Berchuck A Record Status This is a critical abstract of an economic evaluation that meets the criteria for inclusion on NHS EED. Each abstract contains a brief summary of the methods, the results and conclusions followed by a detailed critical assessment on the reliability of the study and the conclusions drawn. Health technology Treatment of early stage endometrial cancer. Type of intervention Treatment. Economic study type Cost-effectiveness analysis. Study population Women with Stage I endometrial cancer. Setting Hospital. The study was carried out at Duke University Medical Center, Durham, North Carolina, USA. Dates to which data relate Effectiveness data were collected from studies previously published between 1969 and Resource use and cost data were collected from a 1995 source. The price year was Source of effectiveness data Effectiveness data were derived from a literature review and authors' assumptions. Modelling A decision analytic model was used to determine the cost-effectiveness of the two treatment strategies. The analytic horizon was from the time of treatment to age 85 years. Outcomes assessed in the review The review assessed the following outcomes: cure and survival rates. Study designs and other criteria for inclusion in the review The authors reviewed existing population and hospital-based reports in the literature. Sources searched to identify primary studies Page: 1 / 5

2 Criteria used to ensure the validity of primary studies Methods used to judge relevance and validity, and for extracting data Summary statistics from each study. Number of primary studies included Approximately 19 studies were included. Methods of combining primary studies Narrative method. Investigation of differences between primary studies Results of the review The authors assumed that hysterectomy yields a 75% cure rate and that adding adjuvant radiation increases the cure rate to 80%. 5-year survival after treatment of well-differentiated endometrial cancer fell from 88% (under 60 years) to 82% (over 70 years) with hysterectomy only and fell from 90% (under 60 years) to 84% (over 70 years) with hysterectomy and adjuvant radiation. 5-year survival after treatment of moderately differentiated endometrial cancer fell from 75% (under 60 years) to 65% (over 70 years) with hysterectomy only and fell from 80% (under 60 years) to 70% (over 70 years) with hysterectomy and adjuvant radiation. 5-year survival after treatment of poorly differentiated endometrial cancer fell from 60% (under 60 years) to 40% (over 70 years) with hysterectomy only and fell from 70% (under 60 years) to 50% (over 70 years) with hysterectomy and adjuvant radiation. If no treatment were performed, survival would range from 1 to 4 years depending on the age at diagnosis and grade of cancer. Survival rates were based on survival numbers from life tables. Methods used to derive estimates of effectiveness In terms of model parameters the authors made a number of assumptions regarding the efficacy of treatments. These were based on the experiences of the authors and on the literature. Estimates of effectiveness and key assumptions The authors assumed that surgical staging had no therapeutic benefit, but allowed individualisation of adjuvant therapy and decreased the number of patients receiving adjuvant therapy from 40% to 20%. It was also assumed that the cure rate did not suffer as a result of decreasing the fraction of cases receiving radiation in the surgically staged group. Measure of benefits used in the economic analysis The number of life years gained was used as the measure of benefits. The number of life years gained was calculated based on expected cure rates for well, moderately, and poorly differentiated cancers and on life tables. Results were presented for both normal healthy women and women with severe medical problems which placed them at a threefold increased hazard of death from other causes. Direct costs Costs were not discounted given the short time frame of the study (less than 1 year). Quantities and costs were reported separately. Direct costs reflected the costs of initial hospitalisation and treatment (including hospital care costs, Page: 2 / 5

3 operating room costs, physician fees, costs of lymph node sampling or radiation). The quantity/cost boundary adopted was that of the hospital. The estimation of quantities and costs was based on actual data. Data on hospital costs were obtained from patients treated at Duke University Medical Center in The price year was Statistical analysis of costs Not reported. Indirect Costs Not included. Currency US dollars ($). Sensitivity analysis Sensitivity analyses were performed on effectiveness and cost estimates. Estimated benefits used in the economic analysis Most of the life years gained are attributable to hysterectomy. The number of life years gained with hysterectomy varied between 1.9 for an 80-year-old woman with grade 3 endometrial cancer and a relative risk of non-cancer death of 3.0, and 34.5 for a 40-year-old woman with grade 1 endometrial cancer and a relative risk of non-cancer death of 1.0. The incremental number of life years gained with hysterectomy and adjuvant radiation over hysterectomy alone varied between 0.1 for an 80-year-old woman with grade 1 endometrial cancer and a relative risk of non-cancer death or 1.0 or 3.0, and 3.7 for a 40-year-old woman with grade 3 endometrial cancer and a relative risk of non-cancer death of 1.0. Cost results The average cost of hysterectomy was $9,000. The average cost of hysterectomy and adjuvant radiation was $11,000. Synthesis of costs and benefits The incremental cost per life year gained with hysterectomy and adjuvant radiation is relatively low, although higher than that for hysterectomy alone. It varied between $545 per life year gained for a 40-year-old woman with grade 3 endometrial cancer and a relative risk of non-cancer death of 1.0, and 33,448 for an 80-year-old woman with grade 1 endometrial cancer and a relative risk of non-cancer death of 3.0. Authors' conclusions The use of hysterectomy and adjuvant radiation in treatment of early endometrial cancer is a worthwhile use of health care resources. CRD COMMENTARY - Selection of comparators The rationale for the choice of the comparator was clear. You, as a user of this database, should verify whether these health technologies are relevant to your setting. Validity of estimate of measure of benefit The number of life years gained was used as the measure of benefits. The authors did not consider quality-adjusted life years (QALYs). More details about the designs of the studies included in the literature review and the method of Page: 3 / 5

4 combining effectiveness estimates could have been provided. The authors acknowledged that the comparability of primary studies was limited by variations in age and racial distribution, staging techniques, stage distribution, type of treatment, length of follow-up, and other factors affecting the outcome. The authors noted that they may have overestimated the curative potential of adjuvant radiation, leading to an under-estimation of the cost per life year gained. Any benefit from prolongation of survival in individuals who are not cured was not accounted for in the model. Validity of estimate of costs Only direct costs were considered. The authors did not include non-medical costs, the costs associated with treatment of diseases in patients who survive endometrial cancer or the costs of treatment of recurrent or terminal endometrial cancer. Professional fees were discounted by about 60% to reflect opportunity costs. Cost estimates were derived from local sources and, hence, are unlikely to be generalisable to other settings. Other issues The authors assumed that the average cost of treatment was the same regardless of whether hysterectomy was followed by radiation in 40% of cases, or whether hysterectomy and surgical staging were followed by radiation in 20% of cases. The model did not account for more subtle potential differences in costs and benefits of these two approaches. Effectiveness and cost estimates included in the model were representative of practice patterns and costs in the USA. The generalisability of these results to other settings or countries was not discussed and no comparisons with other relevant studies were provided. Implications of the study The present model offers a means of comparing the two strategies examined, but more sophisticated models may help determine the cost-effectiveness of various treatment strategies in specific subgroups of patients. Source of funding None stated. Bibliographic details Ashih H, Gustilo-Ashby T, Myers E R, Andrews J, Clarke-Pearson D L, Berry D, Berchuck A. Cost-effectiveness of treatment of early stage endometrial cancer. Gynecologic Oncology 1999; 74(2): PubMedID DOI /gyno Original Paper URL Other publications of related interest 1. Martin-Hirsch P L, Lilford R J, Jarvis G J. Adjuvant progestagen therapy for the treatment of endometrial cancer: review and meta-analysis of published randomised controlled trials. European Journal of Obstetrics, Gynecology, and Reproductive Biology 1996;65(2): Spirtos N M, Schlaerth J B, Gross G M, Spirtos T W, Schlaerth A C, Ballon S C. Cost and quality-of-life analyses of surgery for early endometrial cancer: laparotomy versus laparoscopy. American Journal of Obstetrics & Gynecology 1996;174(6): Page: 4 / 5

5 Powered by TCPDF ( Indexing Status Subject indexing assigned by NLM MeSH Adult; Aged; Aged, 80 and over; Combined Modality Therapy; Cost-Benefit Analysis; Decision Support Techniques; Endometrial Neoplasms /drug therapy /economics /pathology /surgery /therapy; Female; Humans; Hysterectomy; Life Expectancy; Middle Aged; Neoplasm Staging; Quality-Adjusted Life Years AccessionNumber Date bibliographic record published 31/05/2000 Date abstract record published 31/05/2000 Page: 5 / 5