Prognostic evaluation of breast cancer patients with evident bone marrow metastasis.

In this study, we aimed to evaluate the clinicopathologic characteristics and prognosis of breast cancer (BC) patients with symptomatic bone marrow metastasis (BMM). Fifty-four BC patients, including patients with and without BMM, were evaluated retrospectively. In particular, the clinicopathologic features and survival of the patients with BMM (n = 27) were assessed and compared with the patients without BMM. All of the patients with BMM also had osseous metastases, and bone was the first site for distant recurrence in the majority of patients in the study group. Anemia was the most frequent symptom at presentation. The median time to BMM was 36.1 months (range 1.6-70.5 months, 95% CI). HER2(+) patients developed BMM earlier than HER2(-) patients (3.2 versus 38.3 months, 95% CI; p = 0.05). Patients with advanced disease at the time of initial BC diagnosis developed BMM earlier than patients with early disease (p = 0.04). Time to development of BMM was significantly shorter in tumors with perinodal infiltration (p = 0.001) and multicentric focus (p = 0.025). Median survival time after the diagnosis of apparent BMM was 6.43 months. Survival after BMM diagnosis in patients with grade III tumors was significantly shorter than in patients with grade I-II tumors (1.43 versus 5.36 months, 95% CI; p < 0.001). Systemic therapy after BMM diagnosis significantly prolonged survival (17.3 versus 0.93 months, 95% CI; p < 0.001). Hormone receptor-positive, high-grade, advanced-stage tumors at the time of initial BC diagnosis were more common in patients with BMM. Invasive lobular histology was also more frequent in patients with BMM. In conclusion, the presence of hormone receptor-positive, multicentric, grade III, advanced-stage tumors may be important risk factors for the development of evident BMM in BC patients. Systemic single-agent chemotherapy can prolong survival in these patients. However, multicenter analyses are required to verify these findings.