Are argyrophilic nucleolar organizer regions good prognostic indicators of survival of patients with esophageal cancer with lymph node metastasis?

Argyrophilic nucleolar organizer regions (AgNORs) were evaluated in 95 samples from primary esophageal squamous cell carcinomas and 75 samples from metastatic lymph nodes. The number of AgNORs per nucleus in primary tumors with positive nodes (n=53, 6.1+/-1.8) was greater than that in primary tumors with negative nodes (n=42, 3.8+/-1.1, P<0.001). In 39 of 53 patients with positive nodes, the numbers of AgNORs per nucleus in metastatic lymph nodes were lower than those in primary tumors. The 5-year survival rate of these patients was 23.7%. However, the numbers of AgNORs per nucleus in metastatic lymph nodes were greater than those of primary tumors in 14 of 53 patients with positive nodes, and 11 of these 14 patients died from recurrence of cancer within 3 years after surgery. These observations suggest that the proliferative activity of cancer cells might be suppressed in the regional lymph nodes. However, cancer cells with higher proliferative activity in the regional lymph nodes than in the primary tumors might overcome immunological defenses and subsequent further metastasis might occur.