Does Famotidine Enhance Tumor Infiltrating Lymphocytes in Breast Cancer?

Abstract
Thirty patients with breast cancer were prospectively randomized into case and control groups receiving 40 mg famotidine preoperatively for 10-14 days and routine premedication, respectively. Surgical specimens were evaluated objectively for tumor infiltrating lymphocytes in the center and in the periphery of the tumor along with evaluation of metastatic lymph nodes for reactive changes. Ten famotidine-treated cases (67%) showed significant lymphocytic infiltration in the center compared to 4 controls (27%) (p =0.03). Eleven cases (77%) had significant lymphocytic infiltration in the periphery (p =0.03) compared to 5 controls (33%). Considering both sites, lymphocytic response was significant in 9 (60%) cases as opposed to only 3 (20%) controls (p =0.03). This response did not correlate with the stage, grade of tumor or menopausal status of patients in either group. Seventy-eight percent (78%) of the cases showed significant reactive changes in the metastatic lymph nodes as compared to 22% in controls (p <0.01). This study suggests that famotidine enhances tumor infiltrating lymphocytes in breast cancer and might have potential as an immunomodulator. A larger confirmatory study is suggested.