Late Brain Oligometastases Diagnosed at Least 36 Months after Cancer Detection are Associated with Favorable Survival Outcome.

Carsten Nieder,Bård Mannsåker,Rosalba Yobuta

doi:10.7759/cureus.6553

Abstract

Objective The aim of this study was to investigate the impact of a long disease-free interval (at least 36 months from the first diagnosis of cancer) on survival in patients with brain oligometastases (maximum four lesions, no extracranial metastases).MethodsThis study involves a retrospective analysis in a group of 89 patients treated with different brain-directed approaches.ResultsWe identified seven patients (8%) with an interval from cancer diagnosis to the development of brain metastases of at least 36 months. The median time interval was five months. The one-year survival rates were 80% (interval of at least 36 months) and 43% (shorter interval), respectively (p = 0.049). Correspondingly, a large difference in actuarial median survival was observed (39.9 months [95% confidence interval, 16.8-63.0 months] versus 9.7 months (95% confidence interval, 6.1-13.3 months). However, the two Kaplan-Meier curves were not statistically significantly different, p = 0.13. In addition to treatment-related differences, the two groups also differed with regard to the type of primary tumor (high versus low rates of non-small cell lung cancer) and gender.ConclusionLate dissemination was uncommon. The often applied strategy of effective local treatment for patients with brain-only oligometastases is warranted, especially if the disease-free interval had been at least 36 months. Larger studies are needed to fully understand the impact of confounding factors, such as gender and tumor biology.

Highlights

A small proportion of patients with brain metastases are diagnosed with brain-only oligometastatic disease [1,2,3]
We identified seven patients (8%) with an interval from cancer diagnosis to the development of brain metastases of at least 36 months
The one-year survival rates were 80% and 43%, respectively (p = 0.049)

Summary

Introduction

A small proportion of patients with brain metastases are diagnosed with brain-only oligometastatic disease [1,2,3]. The fact that a significant proportion of patients are diagnosed with additional metastases within one year of local ablation illustrates the current challenges of diagnostic imaging (presence of small metastases below the threshold of detection), and tumor biology and genetics, as comprehensively reviewed in references [15,16,17]. In a report by Pastorino et al, five-year overall survival was 45% for patients with a disease-free interval of at least 36 months [19]. Treatment consisted of lung metastasectomy in more than 5000 cases In light of this scientific background, we chose to study the pace of dissemination in a different context, i.e. brain oligometastases. We hypothesized that slow dissemination (disease-free interval at least 36 months) would be associated with longer survival in this patient population

Methods

Results

Discussion

Conclusion