Table 4.
Demographic and clinicopathologic features of breast cancer patients*
| Patient characteristic | No. (%) |
| Case patients, Total No. | 223 |
| Mean (±SD) age at diagnosis, y | 55.0 (±13.7) |
| Race | |
| AA | 136 (61) |
| EA | 87 (39) |
| TNM stage | |
| ≤II | 167 (81) |
| ≥III | 40 (19) |
| Node status | |
| Negative | 132 (63) |
| Positive | 76 (37) |
| Grade | |
| 1 and 2 | 96 (49) |
| 3 | 101 (51) |
| ER status | |
| Negative | 91 (41) |
| Positive | 131 (59) |
| HERV-K env | |
| Negative (score 0) | 75 (34) |
| Positive (score>0) | 148 (66) |
| NOS2 | |
| Low | 68 (30) |
| High | 155 (70) |
Patients with missing information were not included. Race was determined by self-identification. Disease staging was performed according to the TNM staging system of the American Joint Committee on Cancer (AJCC) (21) and the Union for International Cancer Control (UICC) (22). Grading was performed according to the Nottingham grading system (23) for breast cancer; overall grades 1, 2, and 3 were based on the cumulative score of glandular differentiation, nuclear pleomorphism, and mitotic count. ER status was determined by immunohistochemistry following guidelines for clinical laboratories to evaluate semiquantitatively ER expression in formalin-fixed paraffin-embedded tissues. A combined score (sum score) of intensity and distribution was used to categorize the immunohistochemical staining for inducible NOS2). Intensity received a score of 0, 1, 2, and 3 if the staining was negative, weak, moderate, or strong, respectively. The distribution received a score of 0, 1, 2, 3, and 4 (for staining distribution <10%, 10% to 30%, >30% to 50%, >50% to 80%, and >80% positive cells, respectively). A sum score was then divided into four groups as follows: negative = sum scores 0–1; weak = sum scores 2–3; moderate = sum scores 4–5; and strong = sum scores 6–7. For statistical analysis, NOS2 immunohistochemistry was dichotomized in low (negative and weak) and high (moderate and strong). The cut point for the statistical analysis of the HERV-K immunohistochemistry score in breast tumors was set at the median. Envelope expression was categorized by intensity (0 = absent; 1 = weak; 2 = moderate; 3 = strong) and distribution (percent tumor positive for envelope) (18). Intensity and distribution scores were multiplied to obtain the final score (0–300) for envelope expression in a tumor. AA = African American; EA = European American (ie, white race of European ancestry in America); ER = estrogen receptor; HERV-K env = envelope protein of human endogenous retrovirus type K; NOS2 = nitric oxide synthase 2.