SYDNEY, AUSTRALIA – Elevated plasma levels of osteopontin were predictive of 3-year recurrence rates and second primary cancers in patients with stage 1 non–small-cell lung cancer, based on data from a prospective cohort study presented at a world conference on lung cancer.
Based on preoperative plasma specimens from 137 patients undergoing resection of stage 1 adenocarcinoma of the lung, a preoperative cut-off point of 49.6 ng/mL for plasma osteopontin was predictive of 3-year recurrence. In a multivariate analysis, patients with levels above the cut-off had a fourfold increase in the risk of recurrence (HR 4.2, 95% CI 1.8-10.2, P = .001).
The cohort was followed for at least 3 years, with a median follow-up of 44 months. There was a recurrence in 56 patients (41%) over the study period; 31 patients (22.5%) had recurrences within 3 years and 23 of those patients had high osteopontin levels. Thirteen had systematic progression, ten had local or regional progression, and eight patients had a second primary non–small-cell lung cancer.
After adjustment for variants such as stage, gender, and tumor size, osteopontin levels were not significantly associated with 5-year survival; however, 3-year systemic or local progression was highly predictive of 5-year mortality, reported Dr. Jessica Donington, associate professor of cardiothoracic surgery at NYU Langone Medical Center, New York, and her colleagues.
"We would like to think that this would be something you would use to help guide adjuvant therapy or cancer surveillance or prevention protocols," Dr. Donington said.
Osteopontin is associated with increased inflammation. Previous research had shown that higher levels of osteopontin predicted poor response to chemotherapy in patients with advanced lung cancer. Also, osteopontin levels are known to have prognostic implications in breast and prostate cancers.
Osteopontin levels above the cut-off point also were predictive of second primary lung cancers. The association wasn’t as strong for second cancers as it was for recurrence, but the association was still significant and may help to guide follow-up.
"This might be the group that you’re going to decide to scan every 3 months," Dr. Donington said.
The conference was sponsored by the International Association for the Study of Lung Cancer. The study was supported by an Early Detection Research Network Grant, the Stephen Banner Lung Cancer Foundation, and an IASLC/Lung Cancer Foundation of America grant.