|
Follow-up in lung cancer: how often and for what purpose? |
Younes R N, Gross J L, Deheinzelin D |
|
|
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 Two different approaches to the follow-up of patients who had undergone complete resection of non-small-cell lung cancer (NSCLC) were studied. The approaches were strict versus symptom follow-up. Strict follow-up comprised frequent visits, imaging and laboratory examinations (physical examinations, chest radiographs, CT scans and liver function tests). Symptom follow-up comprised less frequent visits (3 or less consultations per year) that were scheduled on the basis of the patient's symptoms.
Economic study type Cost-effectiveness analysis.
Study population The study population consisted of patients who had undergone a complete resection of NSCLC (lobectomy or pneumonectomy with systematic mediastinal lymph node dissection).
Setting The setting was secondary care. The economic study was carried out in Sao Paulo, Brazil.
Dates to which data relate The effectiveness and resource use data were gathered between June 1983 and June 1993. The price year was not reported.
Source of effectiveness data The effectiveness data were derived from a single study.
Link between effectiveness and cost data The costing was performed retrospectively on the same sample of patients as that used in the effectiveness study.
Study sample Power calculations do not appear to have been performed. A sample of 130 consecutive eligible patients was identified at the study hospital, where eligibility was based on the availability of follow-up data for at least two years (or death if it occurred before). There were 67 patients in the strict follow-up group. Their mean age was 60.7 (+/- 9.7) years and 55 were men. There were 63 patients in the symptom follow-up group. Their mean age was 58.8 (+/- 8.7) years and 56 were men.
Study design This was a retrospective comparative study with a historical control, which was presumably carried out in a single centre. The patients were allocated to the study groups according to the policy established at the study hospital at the moment of patient presentation. All patients admitted up to 1990 were followed up with the symptom-oriented approach, while after 1990 a policy of strict follow-up was established. The patients were followed for two years or until death (whichever occurred earlier). No loss to follow-up was observed as the patients' charts were selected in order to have all follow-up data.
Analysis of effectiveness All patients included in the initial study sample were take into account when estimating the effectiveness. The primary health outcomes used in the economic analysis were the number of recurrences in the first 24 months, median survival after recurrence, the treatment and outcome of health problems detected during follow-up, and the salvage rate. At baseline, the study groups were comparable in terms of their age, gender, histology, stage of disease, type of operation, preoperative health problems and adjuvant treatment (chemotherapy, radiotherapy or none).
Effectiveness results In the strict follow-up group there was 1 local recurrence, 13 distant recurrences, and no local and distant recurrences.
The corresponding numbers in the symptom follow-up group were 2 (local), 15 (distant) and 1 (local and distant).
In the strict follow-up group, 3 cases of recurrent cancer were diagnosed using chest radiographs, 4 using chest and abdomen CT, one using liver function test, 2 using consultation, and 4 on the basis of symptoms.
In the symptom follow-up group, 2 cases of recurrent cancer were diagnosed using chest radiographs, 3 using chest and abdomen CT, none using liver function tests, one using consultation, and 12 on the basis of symptoms.
Only the difference in the number of recurrences detected between the groups on the basis of symptoms reached statistical significance.
The median survival after recurrence was 7.9 months in the strict follow-up group and 6.6 months in the symptom follow-up group, (p=0.219).
There was no significant difference in the disease-free survival curves. There were also no significant difference between the two groups in the disease-free interval between the operation and the first detection of recurrence.
The proportion of health problems detected in the emergency room was 45% in the strict follow-up group and 79% in the symptom follow-up group. The mean episodes detected in the emergency room were 0.6 (+/- 1.5) in the strict group and 1.9 (+/- 1.6) in the symptom group, (p<0.001).
The salvage rate for recurrent cancer was similar in both groups.
Clinical conclusions The effectiveness analysis showed that the two follow-up approaches led to similar recurrence rates and survival. In addition, there was no difference in the interval between operation and detection of the first recurrence. However, strict follow-up permitted the earlier treatment of health problems other than cancer recurrence. This resulted in significant decreases in the number of emergency room admissions and, consequently, prevented the late diagnosis of health problems.
Measure of benefits used in the economic analysis The health outcomes were left disaggregated and no summary benefit measure was used. A cost-consequences analysis was therefore conducted. However, it is worth noting that most of the outcome measures used in the effectiveness study showed that there was no statistically significant difference between the two study groups.
Direct costs Discounting was not relevant since the costs were incurred during two years. The unit costs were reported separately from the quantities of resources used. The health services included in the economic evaluation were all the procedures performed, such as chest radiographs, chest and abdominal CT, live function tests and consultations. The cost/resource boundary adopted in the study appears to have been that of the third-party payer. Resource use was estimated using data the charts of the patients involved in the effectiveness study. The unit costs were derived from actual data from the study institution. All of the costs were inflated to current prices, but the price year was not reported.
Statistical analysis of costs Statistical analyses were conducted to test the statistical significance of differences in the estimated costs and resource use.
Indirect Costs The indirect costs were not included in the economic analysis.
Sensitivity analysis Sensitivity analyses were not conducted.
Estimated benefits used in the economic analysis See the 'Effectiveness Results' section.
Cost results The estimated total costs were $2,720.30 (+/- $665.92) in the strict follow-up group and $1,217.94 (+/- $1,113.16) in the symptom follow-up group, (p<0.001).
Synthesis of costs and benefits Not relevant because a cost-consequences analysis was carried out.
Authors' conclusions The two follow-up approaches for patients who had undergone complete resection of non-small-cell lung cancer (NSCLC) were similarly effective in terms of survival and recurrence rates. However, the costs were far lower with the symptom-oriented follow-up than with the strict follow-up strategy. The authors also suggested a routine follow-up scheme, which consisted of 8 physical examination visits (at 1, 2 and 3 weeks, and at 2, 6, 9, 12, 18 and 24 months) and 6 chest radiographs (at 1 and 3 weeks, and at 6, 12, 18 and 24 months).
CRD COMMENTARY - Selection of comparators The rationale for the choice of the interventions compared in the analysis was clear. The two follow-up routines under study represented two approaches followed at the authors' institution for the management of patients who had undergone resection of NSCLC. You should evaluate whether they represent widely used approaches in your own setting.
Validity of estimate of measure of effectiveness The effectiveness analysis used a retrospective comparative study with a historical control, which was appropriate for the study question. The study sample appears to have been representative of the study population at that institution. The length of follow-up was reported. No patient was lost to the final assessment because the patient selection process aimed to identify patients presenting with full data. The study groups were perfectly matched at baseline, so confounding due to those factors is unlikely. However, the retrospective design of the study and the lack of power calculations may have represented a limitation of the analysis. The method of allocating patients to the study groups was not based on randomisation. The authors did not provide any evidence that the initial study sample was adequate for the objective of the analysis. Since the groups were not concurrent, there may be confounding factors that were unaccounted for.
Validity of estimate of measure of benefit No summary benefit measure was used in the economic analysis. The analysis was therefore categorised as a cost-consequences study.
Validity of estimate of costs The perspective adopted in the study was not explicitly stated, but it appears to have been that of the third-party payer. Only the costs of the procedures involved in the follow-up programmes were included in the analysis. The costs were reported separately from the quantities of resources, thus facilitating the reproducibility of the study. Statistical analyses were conducted to test the statistical significance of the difference in both the costs and quantities. The cost estimates were based on US data and no sensitivity analyses were performed. No price year was reported, thus it is quite difficult to perform reflation exercises in other settings.
Other issues The authors compared some of their findings with those from other studies and found similar results. However, the issue of the generalisability of the study results to other settings was not addressed and sensitivity analyses were not conducted. Thus, the external validity of the analysis was low. The study referred to patients who had undergone complete resection of NSCLC and this was reflected in the conclusions of the analysis.
Implications of the study The study results suggest that symptom-oriented follow-up represented a more convenient approach than strict follow-up after complete resection of NSCLC. However, the authors noted that their findings should be supported by further research based on a prospective, randomised design and stratification of health problems according to pathologic stage.
Bibliographic details Younes R N, Gross J L, Deheinzelin D. Follow-up in lung cancer: how often and for what purpose? Chest 1999; 115(6): 1494-1499 Other publications of related interest Comment: Chest. 1999 Jun;115:1487-8.
Indexing Status Subject indexing assigned by NLM MeSH Carcinoma, Non-Small-Cell Lung /diagnosis /economics /mortality /surgery; Cost-Benefit Analysis; Disease-Free Survival; Female; Follow-Up Studies; Humans; Lung Neoplasms /diagnosis /economics /mortality /surgery; Male; Middle Aged; Neoplasm Metastasis /diagnosis; Neoplasm Recurrence, Local /diagnosis /mortality /prevention & Office Visits; Pneumonectomy; Retrospective Studies; Survival Rate; Tomography, X-Ray Computed; control AccessionNumber 21999001225 Date bibliographic record published 31/01/2004 Date abstract record published 31/01/2004 |
|
|
|