Treatments and survival benefits compared for early stage lung cancer
Removal of an entire lung lobe may offer patients with early stage lung cancer better overall survival compared with a partial resection, and stereotactic ablative radiotherapy (SABR) may offer the same survival benefit as a lobectomy for some patients, according to a new study.
The research is the largest population-based study to review modern treatment modalities for early stage lung cancer. It was published in JAMA Surgery (2014; doi:10.1001/jamasurg.2014.556).
According to the American Cancer Society (ACS), in 2014, 224,210 people in the United States are expected to develop lung cancer, and more than 159,260 will die from the disease.
Yet with the aging of the baby-boomer population colliding with acceptance of spiral CT as a screening tool for lung cancer, the number of diagnoses is expected to rise dramatically, said first author Shervin M. Shirvani, MD, attending radiation oncologist at Banner MD Anderson Cancer Center in Gilbert, Arizona, and an adjunct professor at The University of Texas MD Anderson Cancer Center in Houston.
The disease is typically a cancer of the elderly, and because of its association with smoking, patients often carry other comorbidities, such as COPD, coronary artery disease, and renal failure.
Three treatment options are widely available for patients with early-stage disease: lobectomy, or removal of the entire lobe of lung; sublobar resection, or removal of the part of the lung that contains the tumor; and SABR, a precise form of radiation therapy delivered over 3 to 5 sessions.
"Currently, lung cancer is one of the most common and fatal cancers, and for the foreseeable future it will be one of the major health epidemics our country faces. Yet we don't have strong evidence-based guidelines for how to best treat the disease—especially when it's discovered early," said Shirvani.
"In the absence of clinical trials, it was important to analyze observational data from a very large database to compare these three modalities. We wanted to compare lobectomy, the treatment generally thought to be the standard of care, to both the smaller surgery and stereotactic ablative radiotherapy, which does not carry surgical risk, and understand which may be best for this elderly patient population with extensive concurrent illnesses."
For the retrospective, population-based study, the researchers analyzed the Surveillance, Epidemiology and End Results (SEER) Medicare database to identify patients treated for non-small cell lung cancer between 2003 and 2009. In total, 9,093 patients were identified. All underwent 1 of 3 treatment strategies: lobectomy (7,215 patients [79.3%]); sublobar resection (1,496 patients [16.5%]); and SABR (382 patients [4.2%]). Of note, said Shirvani, is that the study's time period reflects the earliest adopters of SABR.
Adjusting for characteristics associated with the patient, the tumor, economic factors, and other co-variables, the researchers found that lobectomy was associated with better overall and lung-specific survival compared with sublobar resection, a finding that surprised the researchers.
"The assumption was that for an elderly patient with a number of co-morbidities, the smaller surgery would be better than a whole lobectomy because there would be fewer surgical complications. Yet, it appears that the ability to eradicate the cancer with the bigger surgery may be more important than minimizing surgical risk," he explained.