HR ceived only a taxane-based regimen. Patients who received the se-gro patients showed tumor size discrepancy cm had an average and 4 respectively). discrepancy of 5 cm between MRI and pathologic evalu-Tumors with low   proliferation showed a higher Pemetrexed ationdetermined size. Patients who received only the taxane-based size discrepancy than did cancers with high   proliferation regimen were found to have an average discrepancy of . The range of 4 and the difference was not signi ant . Two tumor size discrepancy was also signi antly different between the low and high   proliferation groups . Clinical Breast Cancer April ment groups. Surgical Pathology Size Aida Kuzucan Figure Hormonally Positi HE -negative Cancer with Low   Proliferation in Right Breast Baseline MRI Before NAC. Follow-Up MRI During NAC Treatment.

Last MRI Scan After NAC Treatment waspleted. MRI Indicated a -cm Residual Tumor AfterWhich Differs Markedly From the -cm Tumor Found at Surgical Pathologic mTOR Inhibitors Examination A Figure Hormonally Positi HE -negative Intrating Lobular Cancer in Right Breast Baseline MRI before NAC. Follow-Up MRI During NAC Treatment. Last MRI Scan After the NAC Treatment waspleted. AfterMRI Showed a -cm Residual Tum Which Differs Markedly From the -cm Tumor Found on Pathologic Examination of the Surgical Specimen . Scattered Residual Tumor Cells Surrounded by Chemotherapy-Associated Chang Which Include Fibrosis and a Lymphocyte Intra are Noted in Pathology A B B C C D D E Discussion With the wide availability of increasingly effective chemotherapy regimens and targeted therapi NAC can induce remarkable tumor shrinkage down to minimal residual tumor burd or even wipe out all invasive cancer and achieve pCR. Imaging assessment of NAC response may provide valuable information about the residual tumor and help plan optimal surgery to achieve a tumor-free margin.-Clinical Breast Cancer April MRI of HE Breast Cancer Figure Triple-Negative Tumor With High   Proliferation in Right Breast Baseline MRI Scan Before NAC. Follow-Up MRI During NAC Treatment. Table Tumor Response and MRI Performance Between Low and High  .

Tumor Last MRI Scan After NAC Treatment waspleted. AfterMRI Indicated a -cm Residual Tum Low   Tumor High   Tumor P Value and Pathologic Examination of the Surgical geeks Specimen Found a -cm Tumor . Note that Tumor Response .pared With Figure , the Residual Tumor in the Accuracy of MRI 0 cm 8 cm 5 Pathologic Examination is More Localized Range of Size Discrepancy cm cm Tumor response was deed as pCR ra and accuracy of MRI was deed as MRI-pathology A B tumor size discrepancy. pared with clinical examinati mammograp and ultrasonogra-p MRI is considered the most accurate method for evaluating the extent of residual tumor after NAC . however it may not de-tect small foci or scattered cancer cells/clusters that need little vascu-lar supply to survive. 3 It is therefore dif ult to determine how much tissue should be remov especially in patients who responded well to the treatment. Of the patients studied in the German preoperative doxorubicin/docetaxel tri more than 0 were treated with breast-conserving surge but of these patients required reexcision. 7 It was found that for surgical planni tumor characteristics and response to NAC.