|
Preventive health care, 1999 update - 3: follow-up after breast cancer |
Temple L K, Wang E E, McLeod R S |
|
|
Authors' objectives The role of follow-up in improving survival and quality of life after breast cancer is evaluated to make recommendations to physicians who provide follow-up care for women who have been treated for early breast cancer.
Searching MEDLINE was searched from January 1966 to January 1998 for published English language literature, combining the MeSH terms 'breast neoplasms' and 'neoplasm recurrence' (local and distant) with limits to 'human'. An additional search using 'breast neoplasms', 'neoplasm recurrence', 'local/diagnosis' and 'mammography' was done to determine the sensitivity of mammography after local excision. Reference lists of retrieved articles were reviewed.
Study selection Study designs of evaluations included in the reviewInclusion criteria for study design are not stated, other than follow-up be at least 5 years. Studies actually included in the review were RCTs, a meta-analysis of RCTs, cohort studies, a case-control study and various retrospective studies.
Specific interventions included in the reviewDetection of distant disease: combination of blood tests, bone scans, liver echography, and chest radiography.
Detection of recurrent ipsilateral disease after breast-conserving therapy: physical examination with or without mammography.
Detection of contralateral breast cancer: physical examination with or without mammography.
Participants included in the reviewWomen who have had stage I to III infiltrating ductal adenocarcinoma of the breast; no clinical evidence of distant disease at the time of diagnosis; when appropriate, adjuvant therapy, if received, was described; women who were followed up for at least 5 years.
Outcomes assessed in the reviewSurvival, disease recurrence and quality of life for distant disease, ipsilateral disease and disease in the contralateral breast.
How were decisions on the relevance of primary studies made?The authors do not state how the papers were selected for the review, or how many of the reviewers performed the selection.
Assessment of study quality The strength of evidence was evaluated using the methods of the Canadian Task Force on Preventive Health Care (see Other Publications of Related Interest no.1). This is shown in an appendix as a hierarchy of evidence from RCT (level I) to expert opinion (level III). It is not stated if, or how, the internal validity of the primary studies was assessed. The authors do not state how the papers were assessed for validity, or how many of the reviewers performed the validity assessment.
Data extraction The authors do not state how the data were extracted for the review, or how many of the reviewers performed the data extraction.
Methods of synthesis How were the studies combined?A narrative synthesis is presented. The strength of the evidence, by study design, is used to judge the reliability of the results. There is no mention of publication bias.
How were differences between studies investigated?Differences between the studies are not formally investigated. Details of participants, the follow-up intervention, and the results from individual studies are tabulated for most, but not all, of the included studies.
Results of the review Distant disease: the role of follow-up in detecting distant disease was assessed from a secondary analysis of 5 RCTs (4105 patients) and 2 other RCTs (2563 patients).
Local recurrence: the role of follow-up in detecting local recurrence was assessed from 6 individual RCTs (5435 patients); one meta-analysis of 10 RCTs (9709 patients); and three cohort studies.
Contralateral disease: the role of follow-up in detecting contralateral disease was assessed from a cohort within one RCT; one prospective cohort study; one historical cohort study; and one case-control study.
Distant disease: A secondary analysis of five RCTs examined relapse after an abnormal blood test result. This found that 6% of the 52% of women with recurrent disease had an elevated alkaline phosphatase level at some point before the metastases was detected. Two RCTs comparing conservative with intensive follow-up showed no difference in survival in women with recurrent disease. No difference was shown in health-related quality of life as measured in one RCT at 6, 12, 24 and 60 months. The women in these trials were under 70 years of age and had received a diagnosis of T1-3, N0-1, M0 breast cancer.
Local recurrence: 6 RCTs of breast conserving surgery in which follow-up, including physical breast examination and mammography, was used to detect ipsilateral disease showed no difference in survival in women with stage I or II breast cancer after 6 and 12 years of follow-up. These trials were not randomised comparisons of follow-up versus no follow-up, nor comparisons of different types of follow-up. The authors also report one cohort study that showed no difference in survival between women who do, and those who do not, experience local recurrence after 5 and 10 years follow-up. They also mention a meta-analysis of RCTs of various surgical therapies with or without radiotherapy that showed that although the local recurrence rate was higher with local excision it did not affect overall survival. Two retrospective cohort studies are described that showed no significant difference in survival between women with palpable recurrences and those with unpalpable recurrences despite there being some evidence that mammography detects lesions earlier or lesions with a more favourable prognosis.
Contralateral disease: in a cohort of women in whom contralateral disease developed during follow-up within an RCT of surgery and radiotherapy, incidence and survival was the subject of a secondary analysis. Follow-up included frequent physical examination of the contralateral breast. No difference was shown in survival between women with and women without contralateral disease at 10-years of follow-up. An historical cohort study and a case-control study looked at the frequency of contralateral disease before and after the implementation of mammography for routine follow-up and found an increased incidence of contralateral disease after the routine use of mammography. Another cohort study compared women in an area where only physical examination was performed, with women in an area where mammography and physical examination was performed. The frequency of contralateral disease was the same, but more tumours were detected at an earlier stage in the area where follow-up included mammography. The authors point out that these last three studies have methodological flaws and none reported survival data.
Authors' conclusions Distant disease: there is good evidence not to include blood test work and diagnostic imaging as part of screening for distant disease.
Local recurrence: there is no evidence that mammography decreases mortality by detecting ipsilateral breast cancer in the conservatively treated breast, but there is indirect evidence that it may be beneficial.
Contralateral disease: there is no direct evidence to suggest that physical examination or mammography, or both, should be used to detect contralateral breast cancer, but there is indirect evidence that it may be beneficial.
CRD commentary There is an adequate description of the review question in terms of inclusion and exclusion criteria, other than the types of studies eligible for inclusion. The search for studies was restricted to English language publications listed in MEDLINE and reference lists of retrieved articles, therefore, there is potential for language, publication, and citation bias. There are no details given about how papers were selected for the review, how the included studies were assessed for internal validity, or how data were extracted, or how many reviewers were involved. The authors, however, do mention adherence to the method of the Canadian Task Force on Preventive Health Care, which is referenced (see Other Publications of Related Interest no.1). Since several study designs have been included, the narrative synthesis is appropriate, and some attempt has been made to discuss the findings in relation to an accepted hierarchy of evidence. Differences between studies of the same design is not addressed. Not all of the individual studies that contribute to the findings are described in the tables. The authors conclusions are not always clearly linked back to the included studies and a more thorough tabulation of all of the included studies would have been helpful. The conclusion that "there is good evidence not to include blood test work and diagnostic imaging as part of screening for distant disease" would be more accurately phrased as 'there is no good evidence to include blood test work...'. The conclusion of indirect evidence of a possible benefit of mammography in detecting local recurrence, and of physical examination or mammography to detect contralateral breast cancer, is reasonable based upon the generally weak or limited evidence presented.
Implications of the review for practice and research Practice: The authors state that laboratory and/or diagnostic screening, for distant disease is not indicated. Although experts recommend frequent physical examination and mammography, there is no direct evidence to support the inclusion or exclusion of this in the follow-up of women with breast cancer. There is no direct evidence that early detection of local recurrence or contralateral disease, or both, improves survival in women after breast cancer.
Research: The authors state that follow-up has not been subjected to rigorous examination in RCTs, and that defining the role of follow-up in improving survival will increase our understanding of breast cancer. The effect of follow-up on quality of life is an important aspect of health care delivery to women that requires further research.
Bibliographic details Temple L K, Wang E E, McLeod R S. Preventive health care, 1999 update - 3: follow-up after breast cancer. CMAJ: Canadian Medical Association Journal 1999; 161(8): 1001-1008 Other publications of related interest 1. Woolf SH, Battista RN, Anderson GM, Logan AG, Wang E. Assessing the clinical effectiveness of preventive manoeuvres: analytic principles and systematic methods in reviewing evidence and developing clinical practice recommendations. J Clin Epidemiol 1990;43:891-905.
This additional published commentary may also be of interest. Perez E. Review: routine follow-up tests do not improve survival and quality of life in women after treatment for early-stage breast cancer. ACP J Club 2000;132:107.
Indexing Status Subject indexing assigned by NLM MeSH Breast Neoplasms /mortality /pathology /prevention & Diagnostic Imaging; Female; Follow-Up Studies; Hematologic Tests; Humans; Mammography; Neoplasm Metastasis /prevention & Neoplasm Recurrence, Local /diagnosis /prevention & Physical Examination; Quality of Life; Survival Analysis; control; control; control AccessionNumber 11999009768 Date bibliographic record published 30/04/2001 Date abstract record published 30/04/2001 Record Status This is a critical abstract of a systematic review that meets the criteria for inclusion on DARE. Each critical abstract contains a brief summary of the review methods, results and conclusions followed by a detailed critical assessment on the reliability of the review and the conclusions drawn. |
|
|
|