The investigational agent erlotinib, which blocks epidermal growth factor receptor tyrosine kinase, shows promise as a treatment for bronchioloalveolar cell carcinoma, especially among patients who never smoked, according to a presentation at the annual meeting of the American Society of Clinical Oncology.

A total of 33 patients with bronchioloalveolar cell carcinoma or adenocarcinomas with clear bronchioloalveolar cell carcinoma features were enrolled in the phase II trial. Of the 33 patients, 9 had never smoked.

Of 30 patients who completed at least 1 month of therapy, 8 achieved a partial response. Of those 8 patients, 5 had never smoked, 2 had smoked 1 pack a day for less than 10 years, and 1 was a former heavy smoker. Progression of the disease led to 2 deaths.

“While it is premature to make any conclusions about survival, we found that this treatment induced regressions that were often dramatic in patients with advanced bronchioloalveolar cell carcinoma, and that the responses seem more durable and meaningful than what we have seen with chemotherapy” said lead investigator Vincent Miller, MD.

Miller expanded on the possible significance of the association between smoking history and response to treatment, saying “The particularly encouraging activity of this drug in never-smokers suggests that tobacco-related genetic changes in this patient population may influence resistance to this drug. Further research is necessary to address this possibility.”

Side effects, such as rash and diarrhea, were present at modest levels in the study population, and researchers noted that the side effects tended to decrease over time.