Shorter diagnostic intervals were observed in (1) PE-NHL patients who had comorbidities (p = 0.02), (2) PE-NHL that caused symptoms of dysphagia (p = 0.04), (3) tumors with the highest proliferative activity (Ki67 > 80%) (p = 0.04), and (4) tumors diagnosed in the advanced stages of the disease (p = 0.004). The gene discussed is MKI67; the disease is non-Hodgkin lymphoma.