title: The effect of tumor subtype on the time from primary diagnosis to development of brain metastases and survival in patients with breast cancer.
abstract: Our group has previously published the Diagnosis-Specific Graded Prognostic Assessment (GPA) showing the prognostic factors associated with survival in patients with brain metastases (BM). The purpose of this study is to investigate the relationship of breast cancer subtype to the time interval from primary diagnosis (PD) to development of BM (TPDBM), number of BM at initial BM presentation and survival. We analyzed our previously described multi-institutional retrospective database of 865 breast cancer patients treated for newly-diagnosed BM from 1993 to 2010. Several factors found to be associated with survival were incorporated into the Breast-GPA, including tumor subtype. The GPA database was further analyzed to determine if the subtype correlated with the TPDBM, number of BM, and survival from PD. After exclusions for incomplete data, 383 patients remained eligible for analysis. The subtypes were approximated as follows: Luminal B: triple positive; HER2: HER2 positive/ER/PR negative; Luminal A; ER/PR positive/HER2 negative; Basal: triple negative. Patients with Basal (90), HER2 (119), Luminal B (98) and Luminal A (76) tumor subtypes had a median TPDBM of 27.5, 35.8, 47.4 and 54.4 months (p < 0.01), median survival from PD of 39.6, 66.4, 90.3 and 72.7 months (p < 0.01) and median survival from BM of 7.3, 17.9, 22.9 and 10.0 months (p < 0.01), respectively. Tumor subtype is an important prognostic factor for survival in patients with breast cancer and BM. Although TPDBM is not an independent prognostic factor for survival (and thus not part of the Breast-GPA), the TPDBM does correlate with tumor subtype but does not correlate with the number of BM. Patients with Basal and HER2 tumor subtypes have short TPDBM. Prospective studies are needed to determine if screening brain MRIs are indicated in patients with Basal or HER2 subtypes.
authors: Minneapolis Radiation Oncology, University of Minnesota Gamma Knife, Minneapolis, MN, USA. psperduto@mropa.com
authors: Paul W
authors: PW
authors: Sperduto
authors: Norbert
authors: N
authors: Kased
authors: David
authors: D
authors: Roberge
authors: Samuel T
authors: ST
authors: Chao
authors: Ryan
authors: R
authors: Shanley
authors: Xianghua
authors: X
authors: Luo
authors: Penny K
authors: PK
authors: Sneed
authors: John
authors: J
authors: Suh
authors: Robert J
authors: RJ
authors: Weil
authors: Ashley W
authors: AW
authors: Jensen
authors: Paul D
authors: PD
authors: Brown
authors: Helen A
authors: HA
authors: Shih
authors: John
authors: J
authors: Kirkpatrick
authors: Laurie E
authors: LE
authors: Gaspar
authors: John B
authors: JB
authors: Fiveash
authors: Veronica
authors: V
authors: Chiang
authors: Jonathan P S
authors: JP
authors: Knisely
authors: Christina Maria
authors: CM
authors: Sperduto
authors: Nancy
authors: N
authors: Lin
authors: Minesh
authors: M
authors: Mehta
mesh_terms: D000328:Adult; D000368:Aged; D001932:Brain Neoplasms / Q000235:genetics / Q000401:mortality* / Q000556:secondary*; D001943:Breast Neoplasms / Q000235:genetics / Q000401:mortality* / Q000473:pathology*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D011379:Prognosis; D016016:Proportional Hazards Models; D018719:Erb-b2 Receptor Tyrosine Kinases / Q000096:biosynthesis / Q000235:genetics; D011960:Receptors, Estrogen / Q000096:biosynthesis / Q000235:genetics; D011980:Receptors, Progesterone / Q000096:biosynthesis / Q000235:genetics; D013995:Time
chemical_list: D018719:Erb-b2 Receptor Tyrosine Kinases; D011960:Receptors, Estrogen; D011980:Receptors, Progesterone