Table 2.

Baseline patient characteristics – oncology history.

All patients (n = 72)LC patients (n = 28)
Histology of primary tumor, n (%)
 Infiltrating ductal carcinoma51 (71%)20 (71%)
 Infiltrating lobular carcinoma2 (3%)2 (7%)
 Inflammatory breast carcinoma2 (3%)0
 Other17 (24%)6 (21%)
Stage at initial breast cancer diagnosis, n (%)
 0/I/IIA/IIB36 (50%)13 (46%)
 IIIA/IIIB/IIIC/IV36 (50%)15 (54%)
Time from primary BC diagnosis to first dose, years
 Median (range)4.4 (0.8–31.0)3.6 (0.8–25.1)
Number of brain metastases
 Median (range)3.0 (1–40)3.0 (1–25)
Size of brain metastases
 At least one target lesion >1 cm, n (%)57 (79%)22 (79%)
 All target lesions measuring 0.5–0.9 cm, n (%)15 (21%)6 (21%)
Time from brain metastases diagnosis to first dose, years
 Median (range)1.1 (0.1–6.4)1.0 (0.1–3.4)
Time from LC diagnosis to first dose, months
 Median (range)NA1.0 (0–12)
HER2 status
 Positive31 (43%)16 (57%)
 Negative41 (57%)12 (43%)
Estrogen receptor status
 Positive39 (54%)17 (61%)
 Negative33 (46%)11 (39%)
Progesterone receptor status
 Positive29 (40%)15 (54%)
 Negative43 (60%)13 (46%)
Patients with triple-negative breast cancer, n (%)19 (26%)4 (14%)
Prior intracranial surgeries, n (%)23 (32%)11 (39%)
 Mean (SD)1.6 (0.8)1.5 (0.7)
 Median (range)1.0 (1–4)1.0 (1–3)
Prior intracranial radiotherapiesa, n (%)61 (85%)21 (75%)
 Mean (SD)2.0 (1.8)1.8 (1.6)
 Median (range)1.0 (1–11)1.0 (1–8)
Prior CNS-directed chemotherapiesb, n (%)18 (25%)10 (36%)
 Mean (SD)1.4 (0.7)1.6 (0.8)
 Median (range)1.0 (1–3)1.0 (1–3)
Prior taxane therapy, n (%)68 (94%)27 (96%)
 Mean (SD)1.6 (0.8)1.4 (0.6)
 Median (range)1.0 (1–4)1.0 (1–3)
Prior anti-HER2 therapy, n (%)35 (49%)18 (64%)
 Mean (SD)3.7 (2.9)2.8 (1.3)
 Median (range)3.0 (1–17)3.0 (1–5)
Prior steroid use, n (%)69 (96%)26 (93%)
 Mean (SD)1.5 (0.6)1.6 (0.7)
 Median (range)1.0 (1–3)1.5 (1–3)
KPS, n (%)
 602 (3%)1 (4%)
 7011 (15%)8 (29%)
 8023 (32%)9 (32%)
 9031 (43%)8 (29%)
 1005 (7%)2 (7%)
  • Abbreviations: BC, breast cancer; CNS, central nervous system; LC, leptomeningeal carcinomatosis; n, number; NA, not applicable; SD, standard deviation; SRS, stereotactic radiosurgery; WBRT, whole brain radiotherapy.

  • aIncluding intensity-modulated radiotherapy (IMRT), SRS, and WBRT.

  • bCNS-directed chemotherapies include intrathecal or systemic therapies.