Table 1.
Demographical and clinical characteristics.
| GRCC | Non-GRCC | |||||
|---|---|---|---|---|---|---|
| Count | % | Count | % | p-Value | ||
| Age | 0–60 years | 78 | 50.3% | 592,544 | 47.3% | 0.46 |
| >60 years | 77 | 49.7% | 659,040 | 52.7% | ||
| Sex | Female | 152 | 98.1% | 1,242,647 | 99.3% | 0.07 |
| Male | 3 | 1.9% | 8937 | 0.7% | ||
| Race | American Indian/Alaska Native | 1 | 0.6% | 6099 | 0.5% | 0.98 |
| Asian or Pacific Islander | 12 | 7.7% | 85,407 | 6.8% | ||
| Black | 16 | 10.3% | 123,081 | 9.8% | ||
| Unknown | 1 | 0.6% | 5967 | 0.5% | ||
| White | 125 | 80.6% | 1,031,030 | 82.4% | ||
| Grade | Well differentiated; Grade I | 5 | 3.2% | 216,525 | 17.3% | <0.001 |
| Moderately differentiated; Grade II | 53 | 34.2% | 446,827 | 35.7% | ||
| Poorly differentiated; Grade III | 64 * | 41.3% | 365,903 | 29.2% | ||
| Anaplastic; Grade IV | 5 * | 3.2% | 16,937 | 1.4% | ||
| Unknown | 28 | 18.1% | 205,392 | 16.4% | ||
| ER Status a | Negative | 58 * | 40.3% | 203,173 | 17.9% | <0.001 |
| Positive | 67 | 46.5% | 807,640 * | 71.1% | ||
| Borderline | 0 | 0.0% | 2837 | 0.2% | ||
| Unknown | 19 | 13.2% | 121,600 | 10.7% | ||
| PR Status a | Negative | 84 * | 58.3% | 310,973 | 27.4% | <0.001 |
| Positive | 40 | 27.8% | 683,610 * | 60.2% | ||
| Borderline | 0 | 0.0% | 5794 | 0.5% | ||
| Unknown | 20 | 13.9% | 134,873 | 11.9% | ||
| HER2 Status c | Negative | 25 | 86.2% | 291,238 | 78.5% | 0.56 |
| Positive | 2 | 6.9% | 52,021 | 14.0% | ||
| Borderline | 0 | 0.0% | 8250 | 2.2% | ||
| Unknown | 2 | 6.9% | 19,359 | 5.2% | ||
| IHC based intrinsic Subtypes c | HER2−/HR+ | 12 | 41.4% | 251,946 * | 67.9% | <0.001 |
| HER2+/HR− | 1 | 3.4% | 15,597 | 4.2% | ||
| HER2+/HR+ | 1 | 3.4% | 36,269 | 9.8% | ||
| Triple Negative | 13 * | 44.8% | 38,750 | 10.4% | ||
| Unknown | 2 | 6.9% | 28,306 | 7.6% | ||
| AJCC 6th Stage | I | 54 | 34.8% | 525,652 | 42.0% | 0.03 |
| II | 59 * | 38.1% | 365,536 | 29.2% | ||
| III | 17 | 11.0% | 139,296 | 11.1% | ||
| IV | 11 | 7.1% | 54,270 | 4.3% | ||
| Unknown | 14 | 9.0% | 166,830 | 13.3% | ||
| T | T0 | 0 | 0.0% | 1110 | 0.1% | 0.01 |
| T1 | 63 | 40.6% | 647,840 * | 51.8% | ||
| T2 | 57 * | 36.8% | 295,198 | 23.6% | ||
| T3 | 7 | 4.5% | 49,233 | 3.9% | ||
| T4 | 3 | 1.9% | 33,931 | 2.7% | ||
| Tis | 0 | 0.0% | 1791 | 0.1% | ||
| Unknown | 25 | 16.1% | 222,481 | 17.8% | ||
| N | N0 | 91 | 58.7% | 718,198 | 57.4% | 0.79 |
| N1 | 32 | 20.6% | 234,449 | 18.7% | ||
| N2 | 9 | 5.8% | 68,563 | 5.5% | ||
| N3 | 6 | 3.9% | 48,862 | 3.9% | ||
| Unknown | 17 | 11.0% | 181,512 | 14.5% | ||
| M | M0 | 132 | 85.2% | 1,083,182 | 86.5% | 0.21 |
| M1 | 11 | 7.1% | 54,270 | 4.3% | ||
| Unknown | 12 | 7.7% | 114,132 | 9.1% | ||
| Bone Metastasis c | No Metastasis | 27 | 93.1% | 351,795 | 94.9% | 0.72 |
| Metastasis | 1 | 3.4% | 13,264 | 3.6% | ||
| Unknown | 1 | 3.4% | 5809 | 1.6% | ||
| Brain Metastasis c | No Metastasis | 27 | 93.1% | 363,212 | 97.9% | 0.03 |
| Metastasis | 1 * | 3.4% | 1501 | 0.4% | ||
| Unknown | 1 | 3.4% | 6155 | 1.7% | ||
| Liver Metastasis c | No Metastasis | 27 | 93.1% | 359,794 | 97.0% | 0.46 |
| Metastasis | 1 | 3.4% | 5079 | 1.4% | ||
| Unknown | 1 | 3.4% | 5995 | 1.6% | ||
| Lung Metastasis c | No Metastasis | 27 | 93.1% | 358,514 | 96.7% | 0.56 |
| Metastasis | 1 | 3.4% | 6,198 | 1.7% | ||
| Unknown | 1 | 3.4% | 6,156 | 1.7% | ||
| Surgery b | No Surgery | 7 | 5.5% | 70,372 | 7.3% | 0.38 |
| Surgery | 118 | 92.9% | 889,255 | 92.0% | ||
| Unknown | 2 | 1.6% | 6822 | 0.7% | ||
| Extent of Surgery b | No Surgery | 8 | 6.3% | 75,877 | 7.9% | 0.51 |
| Sub-Mastectomy # | 70 | 55.1% | 485,610 | 50.2% | ||
| Mastectomy | 48 | 37.8% | 401,380 | 41.5% | ||
| Surgery, Unknown | 0 | 0.0% | 1358 | 0.1% | ||
| Unknown | 1 | 0.8% | 2224 | 0.2% | ||
| Radiation b | No Radiation | 64 | 50.4% | 426,196 | 44.1% | 0.21 |
| Radiation | 58 | 45.7% | 513,445 | 53.1% | ||
| Unknown | 5 | 3.9% | 26,808 | 2.8% | ||
Bolded are statistically significant p-values when comparing between clear cell/glycogen rich to other carcinomas of the breast. * Statistically significant differences between column proportions. # Defined as any surgery less aggressive than total mastectomy. a,b,c Variable available for cases diagnosed after 1990, 1998 and 2010 respectively. GRCC—glycogen-rich clear cell; ER—estrogen receptor; PR—progesterone receptor; IHC—immunohistochemistry; HER2—human epidermal growth factor receptor 2; HER2+—human epidermal growth factor receptor 2 positive; HER2−—human epidermal growth factor receptor 2 negative; HR+—hormone receptor positive; HR−—hormone receptor negative; AJCC—American Joint Committee on Cancer; T, N, M refers to tumor size, nodal status, and metastasis classifications of malignant tumor staging system, respectively.