Smoking status does not impact outcomes with anti-PD-1 therapy

CHICAGO — Smoking status did not affect biomarkers, immune-related adverse events or survival among patients treated with anti-PD-1 therapy for non-small cell lung cancer, according to a study presented at the International Association for the Study of Lung Cancer Multidisciplinary Symposium in Thoracic Oncology.

“People have done studies that show smoking while you have cancer increases some mutations within the cancer, which makes the tumor more immunogenic. As the tumor becomes more immunogenic, response to immunotherapy improves,” Maida Hafiz, MD, resident at East Carolina University Brody School of Medicine, told HemOnc Today. “But, what they have not seen is if this improved response actually translates into improved OS. We tried to see if there was actually a difference in OS between smokers and nonsmokers and if there is a difference in biomarkers before starting immunotherapy.”

Hafiz and colleagues enrolled 99 patients (median age, 64 years) with advanced NSCLC and small cell lung cancer. Patients received nivolumab (Opdivo, Bristol-Myers Squibb) after a first-line platinum doublet between April 2015 and March 2017.

Self-reported smoking history was categorized as never, former smoker (more than 5 pack-years, quit more than 1 year prior) or current smoker. Researchers used chi-square test and t-tests to measure correlation between variables.

The most common histology of NSCLC was adenocarcinoma (46%) followed by squamous cell (42.5%).

A majority of patients reportedly quit smoking (67.7%) at initiation of anti-PD-1 therapy.

The entire cohort had a median number of 35 pack-years. Patients with adenocarcinoma demonstrated higher mean pack-years than those with squamous NSCLC (52.5 vs. 28; P < .001).

Seven patients were never-smokers.

Researchers found no difference between smokers and nonsmokers regarding baseline serum inflammatory biomarkers, including c-reactive protein, albumin and neutrophil/lymphocyte ratio.

In addition, researchers observed no difference in current smoking status and number of pack-years between patients with grade 2 to grade 4 immune-related adverse events (38.4%) and the rest of the cohort.

Median OS after anti-PD-1 initiation was 6.1 months in active smokers and 8.5 months in patients who did not smoke while on immunotherapy, which did not represent a significant difference.

“There is debate on if a person is a smoker, should we actually ask them to quit smoking if their response to immunotherapy actually improves because of smoking,” Hafiz said. “No one has actually seen the translation of this improved response to an improved outcome. We need a study to look at the two simultaneously to see if response while smoking actually translates into an improved outcome.” – by Melinda Stevens

Reference:

Hafiz M, et al. Abstract PS02.12. Presented at: International Association for the Study of Lung Cancer Multidisciplinary Symposium in Thoracic Oncology; Sept. 14-16, 2017; Chicago.

Disclosure: Hafiz reports no relevant financial disclosures.