asco 2013--for Stage IVs deciding whether or not to remove the primary tumor

[Lani]

those Stage IVs who are her2+ benefit more from having primary removed

Use of locoregional treatment to improve survival in de novo stage
IV breast cancer patients with luminal-like and HER2-rich
subtypes.


Citation:
J Clin Oncol 31, 2013 (suppl; abstr e12003)

Author(s): Pengyu Chen, Skye H Hong-Chun Cheng; Koo Foundation Sun Yat-Sen Cancer Center, Taipei
City, Taiwan
Abstract Disclosures
Abstract:
Background: Breast cancer has three major subtypes, including luminal-like (hormone receptor positive, no
HER2 overexpression), HER2-rich (HER2 overexpression), and triple negative (hormone receptor negative
and no HER2 overexpression). This study is to analyze the prognosis in each subtype of stage IV breast
cancer patients. Methods: We reviewed 246 patients with de novo stage IV breast cancer treated at our
hospital between 1990 and 2009. Multivariable Cox analysis was used to determine the survival associated
the subtypes and clinicopathologic factors. Results: Patients with luminal-like subtype are mostly
premonopausal (66.9%, P=0.0002), with abnormal CA 15-3 level at initial diagnosis (58.7%, P=0.01), with
higher rate of bone mets (78.1%, P=0.02), and less rate of liver mets (23.1%, P<0.0001). Patients with HER2-
rich and triple negative had higher rate of nuclear grade III of primary breast tumor, up to 35% and 40%,
respectively (P=0.01). There is no difference in the systemic chemotherapy (82.2~95%, P=0.09) and
locoregional treatment (40.0~51.2%, P=0.23) among three groups. The median overall survival of 246
patients was 23.1 months. The median overall survival in patients with luminal-like, HER2-rich, and triple
negative subtype were 39.6, 17.9, and 13.3 months, respectively (P<0.0001). In multivariate analysis,
hormone receptor and HER2 status were significant independent factors associated with survival (P<0.0001).
Other significant factors associated with survival included liver mets (Hazard Ratio 2.3, P<0.0001), lung mets
(Hazard Ratio 1.7, P=0.0004), and brain mets (Hazard Ratio 1.5, P=0.03). In subgroup analysis, locoregional
treatment to primary breast tumor had significant survival benefit in patients with luminal-like (P=0.0001)
and HER2-rich(P=0.0012) subtype. In triple negative subtype, local treatment did not improve outcome
(P=0.9575). Conclusions: Hormone receptors and HER2 status are the most important factors affecting
survival for these patients. Locoregional treatment to primary breast tumor may provide better outcome,
especially those with luminal-like or HER2-rich subtype.