Sonography in the Diagnosis of Axillary Lymph Node Metastases in Breast Cancer

A systematic review 1 including 16 studies was abstracted in DARE. 14 studies were prospective and 8 of these recruited consecutive patients.

Studies that included axillae with both palpable and non-palpable nodes: In studies in which the criterion for positivity was based on size, the sensitivity ranged from 66 to 73% and the pooled sensitivity was 69% (95% CI 63 to 75, no evidence of heterogeneity) and the specificity ranged from 44 to 98% and the pooled specificity was 75% (95% CI 70 to 80, with strong evidence of heterogeneity, p<0.001). In studies in which the criterion for positivity was based on morphology, the sensitivity ranged from 55 to 92% and the specificity from 80 to 97%. The pooled sensitivity and pooled specificity were 71% (95% CI 65 to 76) and 86% ( 95% CI 83 to 89) respectively; there was strong evidence of heterogeneity in both measures (p<0.003).

Studies that included axillae with non-palpable nodes only: In studies in which the criterion for positivity was based on size, the sensitivity ranged from 49 to 87% and the specificity from 78 to 97%. The pooled sensitivity and pooled specificity were 61% (95% CI 55 to 67) and 77% (95% CI 72 to 82), respectively; there was strong evidence of heterogeneity in both measures (p<0.001). In studies in which the criterion for positivity was based on morphology, the sensitivity ranged from 26 to 76% and the specificity from 89 to 98%. The pooled sensitivity and pooled specificity were 44% (95% CI 65 to 76) and 92% (95% CI 89 to 95%), respectively; there was strong evidence of heterogeneity in both measures (p<0.02).

Sonographically guided biopsy: In needle biopsy studies, the sensitivity ranged from 25 to 95% and the pooled sensitivity was 75% (95% CI 70 to 79) with strong evidence of heterogeneity (p<0.001). Specificity was 97% in 1 study and 100% in all other 7 studies. In studies of all axillae, the sensitivity ranged from 6 to 63% and the pooled sensitivity was 45% (95% CI 40 to 51) with strong evidence of heterogeneity (p<0.001). Specificity was 100% in all studies.

Comment: The quality of evidence is downgraded by limitations in both study and review quality, by potential reporting bias, and by inconsistency (heterogeneity between the studies).

References

• Alvarez S, Anorbe E, Alcorta P, et al. Role of sonography in the diagnosis of axillary lymph node metastases in breast cancer: a systematic review. American Journal of Roentgenology 2006; 186(5): 1342-1348 [DARE]