Table 3. Comparison of Clinicopathologic Characteristics between Invasive Lobular Carcinoma and Invasive Ductal Carcinoma.
| Parameters | Total, n=835 (%) | IDC, n=721 (%) | ILC, n=114 (%) | p value |
|---|---|---|---|---|
| Age (yrs) | 0.832 | |||
| <50 | 491 (58.8) | 428 (59.4) | 63 (55.3) | |
| ≥50 | 344 (41.2) | 293 (40.6) | 51 (44.7) | |
| Histologic grade | <0.001 | |||
| I/II | 594 (71.1) | 485 (67.3) | 109 (95.6) | |
| III | 241 (28.9) | 236 (32.7) | 5 (4.4) | |
| T stage | 0.058 | |||
| T1 | 422 (50.5) | 355 (49.2) | 67 (58.8) | |
| T2/T3 | 413 (49.5) | 366 (50.8) | 47 (41.2) | |
| Lymph node metastasis | 0.026 | |||
| Absent | 507 (60.7) | 427 (59.2) | 80 (70.2) | |
| Present | 328 (39.3) | 294 (40.8) | 34 (29.8) | |
| ER | <0.001 | |||
| Negative | 266 (31.9) | 259 (35.9) | 7 (6.1) | |
| Positive | 569 (68.1) | 462 (64.1) | 107 (93.9) | |
| PR | <0.001 | |||
| Negative | 366 (43.8) | 347 (48.1) | 19 (16.7) | |
| Positive | 469 (56.2) | 374 (51.9) | 95 (83.3) | |
| HER-2 | <0.001 | |||
| Negative | 672 (80.5) | 565 (78.4) | 107 (93.9) | |
| Positive | 163 (19.5) | 156 (21.6) | 7 (6.1) | |
| Ki-67 LI | <0.001 | |||
| ≤14 | 501 (60.0) | 409 (56.7) | 92 (80.7) | |
| >14 | 334 (40.0) | 312 (43.3) | 22 (19.3) | |
| Molecular type | <0.001 | |||
| Luminal A | 389 (46.6) | 303 (42.0) | 86 (75.4) | |
| Luminal B | 191 (22.9) | 169 (23.4) | 22 (19.3) | |
| HER-2 | 72 (8.6) | 71 (9.8) | 1 (0.9) | |
| TNBC | 183 (21.9) | 178 (24.7) | 5 (4.4) |
IDC, invasive ductal carcinoma; ILC, invasive lobular carcinoma; ER, estrogen receptor; PR, progesterone receptor; LI, labeling index; HER-2, human epidermal growth factor receptor-2; TNBC, triple-negative breast cancer.