Expression of intercellular adhesion molecule-1 in invasive breast cancer reflects low growth potential, negative lymph node involvement, and good prognosis.

To understand the role of intercellular adhesion molecule-1 (ICAM-1) in tumor progression in the host, we examined ICAM-1 expression in breast cancer by immunohistochemistry. This study included 274 female patients with invasive breast cancer, with a median follow-up of 98 months. The molecule was identified in formalin-fixed, paraffin-embedded primary tumors, and the relationship to clinicopathological factors and prognosis was analyzed. ICAM-1 expression occurred in 50.3% of patients. ICAM-1 expression had negative correlation to tumor size (P = 0.003), lymph node metastasis (P < 0.0001), tumor infiltration (P = 0.003), nuclear pleomorphism (P = 0.004), and nuclear grade (P = 0.042). Patients with ICAM-1-positive tumors had better relapse-free and overall survival than those with negative tumors (P < 0.0001 and P = 0.0003, respectively). These results suggest that expression of ICAM-1 on cancer cells might have a role as a suppressor of tumor progression under the host immune surveillance system.