Accuracy of contrast-enhanced computed tomography in the prediction of residual breast cancer after neoadjuvant chemotherapy.

Determination of the extent of residual disease after neoadjuvant chemotherapy is sometimes inaccurate by conventional diagnostic methods. The purpose of this study was to evaluate the accuracy of contrast-enhanced computed tomography (CE-CT) in depicting the extent of residual carcinomas. Fifty-seven patients with breast carcinomas of 3 cm diameter or more received neoadjuvant chemotherapy with four cycles of AT (doxorubicin and docetaxel). Before surgery, the patients underwent clinical examination, mammogram (MMG), ultrasonography (US), and CE-CT. Thirteen patients were not evaluated by CE-CT before surgery. Enhancement patterns on CE-CT were classified into multiple spots, tumor and spots, solid tumor type, and no enhancement. When all types of cancers were included in the analysis, clinical examination showed the best correlation with the pathology of the extent of residual carcinomas. However, except in invasive lobular carcinoma (ILC) and inflammatory breast carcinoma (IBC), CE-CT showed the best correlation (R insertion mark2 = 0.537). More than half of the residual microcalcifications on MMG after neoadjuvant chemotherapy suggested residual viable tumor. In conclusion, CE-CT is the most accurate noninvasive technique for identifying the extent of the residual carcinoma after neoadjuvant chemotherapy if cases of IBC and ILC are excluded.