Wendy Bruening

Systematic Review: Comparative Effectiveness of Core-Needle and Open Surgical Biopsy to Diagnose Breast Lesions

BACKGROUND Most women undergoing breast biopsy are found not to have cancer. PURPOSE To compare the accuracy and harms of different breast biopsy methods in average-risk women suspected of having breast cancer. DATA SOURCES Databases, including MEDLINE and EMBASE, searched from 1990 to September 2009. STUDY SELECTION Studies that compared core-needle biopsy diagnoses with open surgical diagnoses or clinical follow-up. DATA EXTRACTION Data were abstracted by 1 of 3 researchers and verified by the primary investigator. DATA SYNTHESIS 33 studies of stereotactic automated gun biopsy; 22 studies of stereotactic-guided, vacuum-assisted biopsy; 16 studies of ultrasonography-guided, automated gun biopsy; 7 studies of ultrasonography-guided, vacuum-assisted biopsy; and 5 studies of freehand automated gun biopsy met the inclusion criteria. Low-strength evidence showed that core-needle biopsies conducted under stereotactic guidance with vacuum assistance distinguished between malignant and benign lesions with an accuracy similar to that of open surgical biopsy. Ultrasonography-guided biopsies were also very accurate. The risk for severe complications is lower with core-needle biopsy than with open surgical procedures (<1% vs. 2% to 10%). Moderate-strength evidence showed that women in whom breast cancer was initially diagnosed by core-needle biopsy were more likely than women with cancer initially diagnosed by open surgical biopsy to be treated with a single surgical procedure (random-effects odds ratio, 13.7 [95% CI, 5.5 to 34.6]). LIMITATION The strength of evidence was rated low for accuracy outcomes because the studies did not report important details required to assess the risk for bias. CONCLUSION Stereotactic- and ultrasonography-guided core-needle biopsy procedures seem to be almost as accurate as open surgical biopsy, with lower complication rates. PRIMARY FUNDING SOURCE Agency for Healthcare Research and Quality.

Observational studies in systemic reviews of comparative effectiveness: AHRQ and the Effective Health Care Program

OBJECTIVE Systematic reviewers disagree about the ability of observational studies to answer questions about the benefits or intended effects of pharmacotherapeutic, device, or procedural interventions. This study provides a framework for decision making on the inclusion of observational studies to assess benefits and intended effects in comparative effectiveness reviews (CERs). STUDY DESIGN AND SETTING The conceptual model and recommendations were developed using a consensus process by members of the methods workgroup of the Effective Health Care Program of the Agency for Healthcare Research and Quality. RESULTS In considering whether to use observational studies in CERs for addressing beneficial effects, reviewers should answer two questions: (1) Are there gaps in the evidence from randomized controlled trials (RCTs)? (2) Will observational studies provide valid and useful information? The latter question involves the following: (a) refocusing the study questions on gaps in the evidence from RCTs, (b) assessing the risk of bias of the body of evidence of observational studies, and (c) assessing whether available observational studies address the gap review questions. CONCLUSIONS Because it is unusual to find sufficient evidence from RCTs to answer all key questions concerning benefit or the balance of benefits and harms, comparative effectiveness reviewers should routinely assess the appropriateness of inclusion of observational studies for questions of benefit. Furthermore, reviewers should explicitly state the rationale for inclusion or exclusion of observational studies when conducting CERs.