Prognostic significance of CD24 protein expression in patients treated with adjuvant radiotherapy after radical hysterectomy for cervical squamous cell carcinoma

Background and purpose: The CD24 marker is expressed in various carcinomas and is associated with shorter survival rates. We evaluated the prognostic significance of CD24 protein overexpression in patients treated with post-operative radiotherapy (RT) after surgery, and its prognostic significance and specific role stratified by adjuvant treatment modalities. Materials and methods: We determined the CD24 expression status of 140 patients with cervical squamous cell carcinoma treated with RT alone or with chemoradiotherapy (CRT) after radical hysterectomy procedures. Results: CD24 expression was detected in 59 patients (42%) and was significantly associated with locoregional failure-free survival (LRFFS) (p = 0.0218), distant metastasis-free survival (DMFS) (p = 0.0001), and overall survival (OS) (p 0.0053). In the multivariate analysis, CD24 positivity was also significantly associated with DMFS (p = 0.025) and OS (p = 0.045). CD24 expression stratified by post-operative treatments (CRT or RT alone) was associated with DMFS (p = 0.0001) but not with LRFFS (p = 0.4423) in the CRT group. However, CD24 expression was associated with LRFFS (p = 0.0198) but not with DMFS (p = 0.5269) in the RT alone group. Conclusions: CD24 expression is an independent prognostic marker in patients with cervical squamous cell carcinoma, even adjuvant treatment after surgery. And this study reveals different prognostic role of CD24 expression in two subgroups treated differently after surgery. Therefore, new therapeutic strategies targeting CD24 expression stratified by subgroups might have important clinical implications. (C) 2010 Elsevier Ireland Ltd. All rights reserved. Radiotherapy and Oncology 95 (2010) 359-364