Thin section computed tomography in the prone position for detection of axillary lymph node metastases in breast cancer.

Presence or absence of lymph node metastases is the most accurate prognostic indicator in breast cancer. Clinical examination is unreliable in detecting involved nodes. Formerly, CT (computed tomography) was concluded to be an unreliable predictor of axillary lymph node involvement, primarily because of its low negative predictive value. In our institute, thin section CT (TS-CT) in the prone position was performed in patients with breast cancer to improve the predictability of axillary lymph node involvement. Pre-operative TS-CT examination of the axilla and breast was performed in 71 women with breast cancer. The sensitivity for involved nodes was 93.8%, the specificity 82.1%, and the accuracy 87. 3%. Based on these results, we concluded that TS-CT is an accurate predictor of axillary lymph node involvement. However, the upper limit of accuracy was approximately 85% for the imaging diagnoses, mainly because of the existance of micrometastases.