Cellular proliferation and angiogenesis in nasal polyps of young adult and geriatric patients

Background: Cellular proliferation and angiogenesis are associated with pathophysiology of nasal polyposis (NP). In a previous report, we showed that patient age is a predictive factor of surgical outcomes among patients with chronic rhinosinusitis and NP, and that geriatric patients exhibit better outcomes than pediatric and adult patients. We postulated that better outcomes in the geriatric population may be secondary to decreased proliferation and angiogenesis within polyps. Therefore, we evaluated the cellular proliferation and angiogenesis in young adult and geriatric patients with NP. This was a prospective case-control study.

Methods: Twenty patients were divided into 2 groups according to age (20 to 30 years vs ≥65 years of age). NP tissues were sampled during endoscopic sinus surgery and processed for immunohistochemistry. Cellular proliferation was evaluated with proliferating cell nuclear antigen and Ki67, and angiogenesis was assessed with vascular endothelial growth factor. We also compared objective surgical outcomes using endoscopy scores.

Results: Immunohistochemical analysis revealed significantly higher expression and positive reactivity of proliferating cell nuclear antigen and Ki67 in the polyps of young adults than in those of geriatric patients, whereas the expression of vascular endothelial growth factor was similar between the 2 groups. Endoscopy scores were better in the geriatric group.

Conclusion: Geriatric patients have a lower cellular proliferative ability than young adults, and angiogenesis does not significantly differ between the 2 age groups. Cellular proliferation seems to be the cause of the different surgical outcomes between the 2 age groups, whereas angiogenesis has no significant influence on the postoperative course.