STS News, Fall 2018 -- Three years into an R01 grant, researchers have made a number of discoveries that will help cardiothoracic surgeons improve patient outcomes after lung cancer surgery.
In 2015, the Agency for Healthcare Research and Quality awarded STS nearly $1 million to study lung cancer survival, surgical approach, and resource use. The research team, led by Felix G. Fernandez, MD, MSc, from Emory University in Atlanta, has completed work on the first two aims; results from the third aim are expected in July 2019.
“This research has leveraged two complementary national datasets to produce a unique cross-linked data infrastructure of individual patient clinical characteristics and longitudinal outcomes that could not otherwise be replicated,” said Dr. Fernandez. “Results from these studies have identified those patients at risk for poor long-term survival following lung cancer surgery and helped determine the optimal surgical strategies and associated costs in such patients.”
Long-Term Survival
The grant’s first aim was to develop a risk model for long-term survival following lung cancer resection. To accomplish this, the researchers linked data from the STS General Thoracic Surgery Database (GTSD) with Medicare claims data, which allowed for long-term follow-up on approximately 26,000 patients aged 65 or older who had undergone lung cancer resection.
“The GTSD, as great as it is, is limited to 30-day clinical outcomes,” Dr. Fernandez said. “What really matters to patients, besides the safety of the surgery, is how long they are likely to live after surgery.”
Following the data linkage, the researchers found that although mortality was 2.2% at 30 days, it increased to 2.6% at 90 days. In addition, 90-day mortality for sublobar and lobar resection was at least double that of the GTSD-reported mortality and also was higher for bilobectomy and pneumonectomy.
“Results from these studies have identified those patients at risk for poor long-term survival following lung cancer surgery.”
Building upon these findings, the researchers then created a long-term survival model, which determined that cancer stage and a patient’s age are strong predictors of survival following lung cancer resection. This model also adjusts for other clinical variables in estimating predicted long-term survival. Results from this study can inform clinical practice by helping lung cancer patients understand their expected survival following surgery based on their unique characteristics.
Other discoveries included:
- A center’s short-term outcomes didn’t necessarily correlate with its long-term results.
- Delirium, blood transfusion, reintubation, and pneumonia had a negative impact on survival 3-18 months after surgery, while sepsis and blood transfusion were associated with a greater risk of mortality after 18 months.
- Perioperative lobectomy outcomes for GTSD participants were superior to outcomes from non-GTSD participants.
Surgical Approach and Resection Extent
With work from the first aim completed, the team then started examining survival based on surgical approach, as well as the extent of lung resection in lung cancer patients.
Performing a comparative effectiveness analysis, the researchers found that minimally invasive surgical techniques for lung cancer resection did not lead to worse outcomes.
“There had been prior data suggesting that perhaps a minimally invasive approach was inferior in terms of lymph node staging compared to a thoracotomy and that this could potentially adversely impact long-term survival,” Dr. Fernandez said. “This comparative effectiveness analysis, however, showed no difference in the two approaches.”
Results from a similar study on outcomes for segmentectomy versus lobectomy for early stage lung cancer will be presented at the STS 55th Annual Meeting in January.
Resource Use and Costs
For the final aim of the project, the research team will compare resource use and costs according to surgical approach and extent of resection, but Dr. Fernandez said that there’s still a major query that needs to be addressed in future research.
“We want to know how our care impacts patient quality of life through patient-reported outcomes,” he said. “That’s a big interest of mine and a potential future topic for a follow-up grant. We know how long patients live, what their complications are, and what the costs are. But what we really don’t know is what impact the therapies have on their quality of life.”
For more information on this grant or other STS-led research projects, contact Robert Habib, Director of the STS Research Center.