1. Case (I) Chemosensitive group

2. (a) Indistinct margined, oval shaped, hyperdense mass in Rt. UIQ with clustered pleomorphic microcalcifications (b) Nearly disappeared mass after NAC Case 1. F/36 Rt. breast cancer, 3 cycle NAC for 2 months ab

3. (c) Indistinct margined, oval shaped, complex echoic mass with parallel orientation in Rt. UIQ (d) Mass is decreased in size about 50% after NAC (4x2.1cm  2x0.6cm). c d

4. (e) Circumscribed, oval shaped, rim enhancing mass in Rt. UIQ on subtraction MRI (f) Mass is disappeared after NAC. * Confirmed as Invasive ductal carcinoma, HER-2 (+) * No residual tumor on final pathology after surgery ef

5. Case 2. F/48 Rt. breast cancer, 3 cycle NAC for 2 months (a) Obscured margined, oval shaped, hyperdense mass in Rt. UOQ Metastatic lymphadenopathy in Rt. axilla (b) Mass and lymphadenopathy are markedly decreased in size after NAC. ab

6. (c) Indistinct margined, oval shaped, hypoechoic mass with parallel orientation in Rt. UOQ (d) Mass is decreased in size about 75% after NAC (7.3x3.9 cm  1.8x1.3cm ). c d

7. (e) Irregular margined, oval shaped, rim enhancing mass in Rt. UOQ on subtraction MRI (f) Mass is marked decreased in size and enhancement after NAC (6cm  2.5cm). * Confirmed as Invasive ductal carcinoma, Triple (-) * Residual tumor size is 1.8cm on final pathology after surgery ef

8. Case 3. F/36 Rt. breast cancer, 3 cycle NAC for 2 months (a) Indistinct margined, oval shaped, isodense mass in Rt. UOQ with multiple axillary lymphadenopathies (b) Decreased in size of breast mass and axillary lymphadenopathies after NAC ab

9. (c) Angular margined, irregular shaped, hypoechoic mass with parallel orientation in Rt. UOQ (d) Enlarged hypoechoic lymph node in Rt. axilla (e) Mass is decreased in size about 34% after NAC (2.1x1.7  1.4x1.1cm) (f) Axillary lymph node is also decreased in size after NAC. c d ef

10. (g) Irregular margined, oval shaped, homogeneously enhancing mass in Rt. UOQ on subtraction MRI. (h) Mass is decreased in size about 31% after NAC (1.9cm  1.3cm). * Confirmed as Invasive ductal carcinoma, Triple (-) * Residual tumor size is 1.3cm on final pathology after surgery g h

11. Case 4. F/26 Rt. breast cancer, 6 cycle NAC for 4 months (a) Indistinct margined, irregular shaped, hypoechoic mass Rt. UOQ (b) Mass is markedly decreased in size (8.3x2.1 cm  1.6x0.9cm ) after 3 months, 4 cycles of NAC. ab

12. (c) Irregular margined, irregular shaped mass in Rt. UOQ on subtraction MRI (d) Mass is disappeared after 4 months, 6 cycles of NAC. * Confirmed as Invasive ductal carcinoma, Triple (-) * No residual tumor on final pathology after surgery c d

13. Case 5. F/35 Lt. breast cancer, 3 cycle NAC for 2 months (a) Indistinct margined, oval shaped, isodense mass in Lt. upper mid portion Metastatic lymphadenopathy in Lt. axilla (b) Mass and lymphadenopathy are markedly decreased in size after NAC. ab

14. (c) Indistinct margined, irregular shaped, hypoechoic mass with parallel orientation in Lt. upper mid portion (d) Mass is decreased in size about 63% after NAC (3x1.5cm  1.1x0.8cm). c d

15. * Confirmed as Invasive ductal carcinoma, ER (+) * Residual tumor size is 2.1cm on final pathology after surgery (e) Irregular margined, lobular shaped, heterogeneously enhancing mass in Lt. upper mid portion on subtraction MRI (f) Mass is marked decreased in size after NAC (4.1cm  2cm). ef