Downregulation of the Cyclin-Dependent Kinase Inhibitor p27kip1 Might Correlate with Poor Disease-Free and Overall Survival in Inflammatory Breast Cancer

PURPOSE: The objective of this study was to evaluate whether p27kip1 downregulation is a prognostic factor in patients with inflammatory breast carcinoma (IBC). PATIENTS AND METHODS: Fifty-eight patients with IBC were treated between January 1994 and July 2002. Median age was 49 years. Thirty-eight patients had baseline biopsy specimens. Patients received preoperative chemotherapy with FAC (5-fluorouracil/doxorubicin/cyclophosphamide; 34%) or FAC followed by a taxane (66%). All patients underwent mastectomies. All patients received radiation therapy and hormonal treatment when indicated. Expression level of p27kip1 was evaluated by indirect immunoperoxidase procedure. The p27kip1 was considered downregulated if nuclear staining was present in < 50% of the neoplastic cells. RESULTS: Thirty-two patients (84%) had p27kip1-downregulated tumors, and 6 patients (17%) had p27kip1-normal tumors. Six patients (16%) exhibited a pathologic complete response. At a median follow-up of 43 months, 25 recurrences (66%) and 27 deaths (71%) occurred. Patients with p27kip1-downregulated tumors had fewer pathologic complete responses (9% vs. 50%; P = 0.03) and had lower 4-year recurrence-free survival (23% vs. 83%; P = 0.03) and overall survival rates (36% vs. 83%; P = 0.01). CONCLUSION: The p27kip1 deregulation manifested by low protein cellular concentration might represent an adverse prognostic marker in IBC and could provide a valuable tool for selecting treatment for this aggressive disease.