Nick Mulcahy

October 06, 2016

BOSTON — During the past decade in the United States, there was an absolute improvement of roughly 20% in the number of elderly patients with early-stage lung cancer treated with radiation alone who were still alive 2 years after treatment, according to new research.

The improvement, which was in both overall and disease-specific survival, coincided with the widespread adoption of stereotactic body radiation therapy (SBRT) as the standard radiation for lung cancer among US centers, said lead study author, Andrew Farach, MD, a radiation oncologist at Houston Methodist Hospital in Texas.

"These numbers are expected to continue to improve," said Dr Farach, because there was no "tapering off" of the increased survival trend among patients treated with radiation during the study period, which ended in 2012.

He spoke at a press briefing here during the American Society for Radiation Oncology (ASTRO) 2016 Annual Meeting.

SBRT delivers radiation more precisely and efficiently than does conventional external-beam radiation, requiring only one to five treatment sessions, he explained. SBRT can serve as the primary definitive treatment for lung cancer, especially in patients of advanced age, who often have multiple medical problems that limit surgery.

"Lung cancer is a disease of the elderly, with an average age of 70 at diagnosis," said Dr Farach.

Dr Farach and colleagues reviewed records for 62,213 patients age 60 years or older who were diagnosed with stage I non-small cell lung cancer between 2004 and 2012 in the United States. The data were obtained from the National Cancer Institute's Surveillance, Epidemiology, and End Results (SEER) database.

Most patients received surgery alone (n = 41,509). A minority received radiation alone (n = 11,589) or no treatment (n = 7373).

The patients treated with radiation alone had the most dramatic improvement in outcomes.

During the study period, among patients treated with radiation alone, the overall survival rate at 23 months rose 19 percentage points, from 39% to 58% (P < .001). And lung cancer–specific survival at 23 months rose 24 percentage points, from 48% to 72% (P < .001).

The improvement in survival among patients treated with surgery alone was less impressive.

The survival rate at 23 months rose 5 percentage points, from 79% to 84% (P < .001) and lung cancer–specific survival rate rose 4 percentage points, from 87% to 91% (P < .001).

Among patients who received no definitive treatment, there was no statistically significant improvement at 23 months in overall survival or lung cancer–specific survival.

"Our findings indicate that physicians should feel confident recommending radiation therapy to patients who are too sick to undergo surgery or who choose not to undergo surgery for other reasons," said Dr Farach in an ASTRO press statement.

Dr Farach also acknowledged that the survival rates after radiation therapy were lower than those among elderly patients who underwent surgery. The difference may be partly due to a selection bias whereby healthier patients received surgery. Use of palliative SBRT and conventional radiation therapy also may have dampened the survival rates among the radiation-alone patients.

A Lot of Untreated Patients

A "striking" finding from the study was the number of patients — more than 7000 — left untreated in this population, he also told reporters.

Dr Farach speculated that the large number may reflect patients diagnosed in the study's early years, when the more time-demanding and less effective conventional radiation therapy was more common than SBRT. In other words, he suggested that some patients may have gone untreated earlier in the study period because the more convenient SBRT was less available.

Brian Kavanagh, MD, from the University of Colorado in Aurora, who moderated the press conference, said that that a majority of the untreated group "probably" could have received SBRT.

He also wondered whether "ageism" may also have been at play. "We certainly do not want to deny older patients access to treatment…if we think it can be delivered safely and effectively," he commented.

Dr Farach and Dr Kavanagh have disclosed no relevant financial relationships.

American Society for Radiation Oncology (ASTRO) 2016 Annual Meeting. Abstract 152. Presented September 26, 2016.

Follow Medscape senior journalist Nick Mulcahy on Twitter: @MulcahyNick

Follow Medscape Oncology on Twitter: @MedscapeOnc


Comments on Medscape are moderated and should be professional in tone and on topic. You must declare any conflicts of interest related to your comments and responses. Please see our Commenting Guide for further information. We reserve the right to remove posts at our sole discretion.
Post as: