METHODS: Nasal polyp samples were obtained during endoscopic sinus surgery and were classified into asthma and nonasthma groups. Immunohistochemistry was performed using antibodies against activated eosinophils, TGF-beta, and myofibroblasts.
RESULTS: The asthma group showed an increased number of activated eosinophils, TGF-beta, and myofibroblasts compared with the nonasthma and control groups. We found no correlation of asthma and aspirin intolerance with the immunohistochemical findings.
CONCLUSIONS: The increased number of myofibroblasts in the nasal polyps of the asthma group may be responsible for the extracellular matrix accumulation, polyp formation, and polyp recurrence.