Abstract P6-07-20: Variables measured at Central Nervous System (CNS) relapse, but not Immunophenotype, identify groups of breast cancer patients with shorter post CNS-relapse survival
Authors: Gómez HL , Pinto JA , Schwarz JL , Vigil CE , Vallejos CS 
Published: August 2014

Objective: We evaluated breast cancer immunophenotype and variables measured at CNS-relapse as prognostic factors in a cohort of Hispanic patients.

Methods: We reviewed data from 2602 breast cancer women in stages I-III diagnosed between 2000 and 2005 at the Instituto Nacional de Enfermedades Neoplásicas, Lima, Perú. According to immunophenotype, tumors were categorized in luminal A (RE+ and/or RP+, HER2−), luminal B (RE+ and/or RP+, HER2+), HER2 (RE−, RP−, HER2+) and triple negative (RE−, RP−, HER2−). Clinicopathological data at diagnosis and at CNS relapse were evaluated and used to calculate prognostic scores according to Recursive Partitioning Analysis (RPA) score, Graded Prognostic Assessment (GPA) Score, and Basic Score for Brain Metastases. Endpoints were time to CNS metastasis and Post CNS-relapse survival.

Results: With a median follow-up of 7.5 years, 818 (31.4%) patients had locoregional or distant recurrence. In total, 159 (6.1%) patients developed CNS metastases, of whom 92 (3.5%) as the first site of recurrence and 22 meningeal metastases were detected. In triple negative, 51 (32.1%) developed SNC metastases, 46 (28.9%) in luminal A, 37 (23.3%) in HER2 and 25 (15.7%) in luminal B patients. Median time since breast cancer diagnosis to SNC metastases was 28.1 months (mo) and the variables influencing it were Clinical T (P &lt; 0.001), clinical stage (P &lt; 0.001), histologic grade (p = 0.005), estrogen and progesterone receptors ((p = 0.026 for both) and inmmunophenotype (P &lt; 0.005). None of these factors was associated with post SNC-recurrence survival. In regard to variables measured at SNC relapse, we couldn't find differences in age groups (&lt;65 vs ≥65 years old; p = 0.662), extracraneal metastases (present, 4.2mo vs absent, 5.3mo), number of brain metastases (&lt;1 vs ≥ 2; p = 0.550) or volume of CNS metastases (&lt;3cm; 7.7mo vs ≥3cm, 5.2mo; p = 0.298). Statistical differences were observed when patients were stratified by control of primary tumor (controlled, 6.3mo; vs uncontrolled, 3.6 mo; P &lt; 0.001), leptomeningeal involvement (present, 3.0mo vs absent, 5.2mo; p = 0.25) and karnofski performance status (≥ 7, 6.5mo vs &lt;7, 3.5mo; p = 0.002). In the multivariate analysis, significant variables related with a shorter post-SNC recurrence survival were a Karnofski performance status &lt;7 (HR 1.46; p = 0.048); uncontrolled primary tumor (HR 1.92; p = 0.001); and leptomeningeal involvement (HR 1.94; p = 0.025). When survival was evaluated stratifying patients according to prognostic scores, we found differences when cases were grouped according to RPA score (Class I, 6.8 mo vs Class II, 5.5 mo vs Class III, 3.5 mo; p = 0.014). GPA scores could not identify groups with significant difference (p = 0.070). The basic score for BM detected groups with significant differences (scores 0–1, 3.7 mo vs score 2, 6.9 mo vs score 3, 6.8 mo).

Conclusions: Prognostic scores calculated from variables measured at CNS relapse are useful to identify groups with shorter post CNS recurrence survival while immunophenotype of breast cancer was unable to identify groups of different prognosis.

Citation Information: Cancer Res 2012;72(24 Suppl):Abstract nr P6-07-20.