Accuracy of ultrasound and clinical examination in the diagnosis of axillary lymph node metastases in breast cancer.

To evaluate the accuracy of ultrasound regarding the axilla using a 3.5 mHz linear probe, a retrospective study was conducted including 115 cases of breast cancer. The clinical examination was more sensitive than echography (68% vs 56%), but not significantly. The ultrasound presented a higher specificity (89% vs 68% P less than 0.05). The positive predictive values were 82% and 92% for clinical examination and ultrasound respectively and the negative predictive values were 50% and 49%. The total accuracy was 68% for the clinical examination and 67% for the echography (NS). Breaking the data into two groups, those with up to three nodes involved and those with four or more, the analysis showed that either the sensitivity of the clinical examination in the second group or the specificity of the ultrasound in both groups, was significantly higher (P less than 0.05). Nevertheless there was no difference in the total accuracy between the two methods in either group. The results suggest that probes with this resolution have not helped clinical examination in the evaluation of the axilla and even the simultaneous use of both methods may fail in one-third of the cases with lymph node metastases.