A 28-year-old woman from Mumbai presents with recurrent genital warts (condyloma acuminata) that regress spontaneously and recur intermittently over 2 years. A 35-year-old woman from Delhi with persistent cervical dysplasia (CIN 2) progresses to invasive squamous cell carcinoma over 3 years despite treatment. Which feature best explains the difference in clinical outcome between these two presentations?