BioProject

Background: Many strategies to define subtypes and treat cancer relies on a presumption of either localized or widespread (poly)metastatic disease. More...

Background: Many strategies to define subtypes and treat cancer relies on a presumption of either localized or widespread (poly)metastatic disease. We proposed an intermediate state of metastasis termed oligometastasis(es) characterized by limited metastatic progression and amenable to treatment by localized methods e.g. surgery or radiotherapy. Methods: To understand the biological basis of oligometastatic and polymetastatic progression, we analyzed microRNA expression patterns from lung tumor samples of patients with less than five metastases at first metastasis presentation and treated with metastasis-directed surgery. Results: Patients were stratified into four subgroups of oligo- and poly-metastatic progression based on the rate of metastatic progression over follow-up period. We prioritized microRNAs between the extremes of oligo- vs. poly-metastatic progression and validated their capacity to distinguish these phenotypes and predict survival in an independent validation dataset. Conclusions: Our results provide further evidence for the biological underpinnings of oligometastasis(es) and potential microRNA candidates to predict progression trajectories of patients and optimize corresponding metastasis-directed treatment. Overall design: We collected tumor samples from 63 patients that (i) had between one and five metastasis(es) at first metastatic presentation and no clinical or radiologic evidence of metastases in the pleural, peritoneal, pericardial or retroperitoneal cavities,(ii) at the time of lung surgery, had every site of known metastases treated with definitive intent, and (iii) had a minimum of 16 months of follow-up after surgery was required. Total RNA were derived from FFPE metastatic tissue samples. Patient samples were subsequently classified into 3 groups: those from patients with high, intermediate and low rates of progression. Less...