Persistent Serum p53 Antibody Titer Following Mastectomy for Locally Advanced Breast Cancer Is Associated with the Recurrence of Cancer in the Central Nervous System

Other: Serum p53 antibody (s-p53-Abs) is induced by p53 overexpression in cancer cells. Therefore, residual cancer cells may be the cause of seropositivity even after radical surgery. Only few reports have evaluated perioperative changes and long-term monitoring of s-p53-Abs titers in patients with breast cancer. This case report presents long-term monitoring of s-p53-Abs titers in a patient with locally advanced breast cancer who developed recurrence in the central nervous system after radical surgery. The s-p53-Abs titer was monitored for 3 years during neoadjuvant chemotherapy and radical surgery in a 38-year-old woman with clinical stage IIB (T2N1M0) breast cancer. The levels of both the carcinoembryonic antigen (CEA) and cancer antigen 15-3 (CA15-3) were within the normal range, but s-p53-Abs test result (54.8 U/ml) was positive. Neither computed tomography nor bone scintigraphy showed any distant metastasis before treatment. The patient received neoadjuvant chemotherapy (epirubicin, 100 mg/m2; cyclophosphamide, 500 mg/m2; and fluorouracil, 500 mg/m2; followed by docetaxel, 75 mg/m2). One and a half year after surgery, s-p53-Abs results remained positive (5.66 U/ml), and brain metastasis was found. Despite resection for brain metastasis, s-p53-Abs titer remained high (5.88 U/ml), and carcinomatous meningitis was found. During the entire clinical course, although s-p53-Abs titers reflected the presence of residual cancer cells, both CEA and CA15-3 results were negative. The perioperative s-p53-Abs titer might be a useful marker for monitoring residual cancer cells in a patient with breast cancer. Recurrence in the central nervous system might be detected using s-p53-Abs monitoring.