High Smac/DIABLO expression is associated with early local recurrence of cervical cancer

Background: In a recent pilot report, we showed that Smac/ DIABLO mRNA is expressed de novo in a subset of cervical cancer patients. We have now expanded this study and analyzed Smac/ DIABLO expression in the primary lesions in 109 cervical cancer patients. Methods: We used immunohistochemistry of formalin- fixed, paraffin- embedded tissue sections to analyze Smac/ DIABLO expression in the 109 primary lesions. Seventy- eight samples corresponded to epidermoid cervical cancer and 31 to cervical adenocarcinoma. The median follow up was 46.86 months ( range 10 - 186). Results: Smac/ DIABLO was expressed in more adenocarcinoma samples than squamous tumours ( 71% vs 50%; p = 0.037). Among the pathological variables, a positive correlation was found between Smac/ DIABLO immunoreactivity and microvascular density, a marker for angiogenesis ( p = 0.04). Most importantly, Smac/ DIABLO immunoreactivity was associated with a higher rate of local recurrence in squamous cell carcinoma ( p = 0.002, log rank test). No association was found between Smac/ DIABLO and survival rates. Conclusion: Smac/ DIABLO expression is a potential marker for local recurrence in cervical squamous cell carcinoma patients.