Abstract 1350P
Background
In NSCLC patients, confirmation of both brain and systemic (BS-cohort) metastasis (mets) at de novo or recurrent stage IV is associated with a poor prognosis. We compared a BS-cohort to brain-only (B) and systemic-disease-only (S) cohorts.
Methods
Clinico-demographic, treatment and survival data were collected retrospectively and analyzed for all patients with met NSCLC diagnosed between Jan 1, 2014 and Dec 31, 2016, seen at Princess Margaret Cancer Centre.
Results
B-cohort patients had a median overall survival (OS) of 18.4 months compared to 11.1 months in BS-cohort and 14.1 months in S-cohort (p=0.007). OS was superior in the sub-cohort of patients presenting with de novo stage IV compared to met recurrence in the B-cohort (21.5 vs 10.2 months respectively; aHR : 2.00 (95%CI 1.19-3.37, p≤0.01)); no corresponding differences were seen within the other two cohorts. 80% of B-cohort patients received upfront local brain treatment, 45% of whom also received systemic treatment, while 6 patients were treated systemically alone. In the 87 patients with de novo stage IV, OS was superior in 24% who had local treatment to both the primary tumor and brain mets compared to patients treated for brain mets alone. This association was significant when adjusting for sex, age and histology/mutational status; aHR : 0.17 (95%CI 0.05-0.53, p=0.002).
Table: 1350P
| Cohort | n (%) | Median age (years) | Female gender | Ethnicity | Never-smokers | Adenocarcinoma morphology | De novo Stage IV | EGFR+ | ALK+ |
| B | 120 (12%) | 67 | 52% | 69% white; 24% Asian | 27% | 77% | 72% | 24% | 4% |
| BS | 226 (23%) | 66 | 50% | 57% white; 30% Asian | 34% | 86% | 92% | 33% | 4% |
| S | 636 (65%) | 69 | 42% | 65% white; 21% Asian | 26% | 72% | 74% | 19% | 5% |
Conclusions
Stage IV NSCLC patients with brain-only mets had superior OS compared to patients with systemic-only mets. In the B-cohort, de novo Stage IV patients had superior OS compared to recurrent patients. In the de novo B-cohort patients, treating both the primary tumor and brain mets correlated with a trend towards improved OS.
Clinical trial identification
Editorial acknowledgement
Legal entity responsible for the study
The authors.
Funding
University of Toronto.
Disclosure
All authors have declared no conflicts of interest.