Source: www.medpagetoday.com
Author: Mike Bassett, Staff Writer, MedPage Today

Head and neck cancer survivors are at an especially high risk for second primary lung cancers, a secondary analysis of the National Lung Screening Trial (NLST) suggested.

After adjustment for various factors including pack-years of smoking, lung cancer incidence among NLST participants with a history of head and neck cancer was more than doubled compared to those without such a history, at 2,080 versus 609 cases per 100,000 person-years (adjusted rate ratio [RR] 2.54, 95% CI 1.63-3.95), reported John D. Cramer, MD, of Karmanos Cancer Institute in Detroit, and colleagues.

According to the findings in JAMA Otolaryngology-Head & Neck Surgery, a non-significant trend toward improved overall survival was observed among those with a history of head and neck cancer who underwent low-dose CT (LDCT) in the trial rather than chest radiography (HR 0.79, 95% CI 0.42-1.52). As was a trend toward better detection of secondary lung cancer detection in those assigned to LDCT (RR 1.55, 95% CI 0.59-3.63).

“The wide CIs, presumably due to the small sample size and number of outcome events, prevent definitive conclusions,” noted Cramer and colleagues.

Still, they argued, “these results support routine annual low-dose CT chest screening for lung cancer in HNC [head and neck cancer] survivors with prior significant tobacco use who are fit enough to undergo treatment with curative intent.”

In a commentary accompanying the study, Sean T. Massa, MD, of Louis University Hospital in St. Louis, and colleagues, also noted the small sample of head and neck cancer survivors available for analysis, “which results in poor precision for several effect estimates.”

But they said the study adds urgency to efforts to reduce head and neck cancer patients’ risk of lung cancer mortality, particularly regarding efforts to provide those patients with smoking cessation support.

“This recommendation is not specific to patients with HNC but is particularly relevant in this group in which smoking rates are high, and ongoing smoking dramatically increases the risk of treatment complications, recurrence, and death,” they wrote. “Additionally, there is likely substantial room for expansion of lung cancer screening in the HNC population considering the very low rate of lung cancer screening in the general population.”

The NLST randomized more than 50,000 participants at high risk for lung cancer in a 1:1 ratio to either LDCT or chest radiography for lung cancer detection. It included individuals ages 55 to 74 with at least a 30 pack-year history of smoking, and who were either current smokers or had quit within the past 15 years. Participants were excluded if they had a cancer diagnosis within the past 5 years.

In this ad hoc secondary analysis, Cramer and colleagues identified 171 head and neck cancer survivors (median 9 years since diagnosis) who took part in the NLST, 82 of whom were screened with LDCT and 89 with chest radiography. Compared with all other patients in the trial, this group was more likely to be male and had a more extensive cigarette smoking history.

Among the 171 patients, 12 second primary lung cancers were detected in the LDCT group (2,610 cases per 100,000 person-years) versus eight in the chest radiography group (1,594 cases per 100,000 person-years).

Cramer and colleagues also found that head and neck cancer survivors were more likely to have significant abnormalities identified with screening. For example, 42.7% had at least one LDCT screening test suspicious for lung cancer compared with 27.0% in the chest radiography group. In addition, 9.8% in the LDCT group underwent an invasive procedure that was related to screening, compared to just 2.2% in the chest radiography group.

“This finding suggests that individuals with a history of HNC may be more likely to experience the risks associated with screening, including subsequent invasive procedures,” they wrote.