CLAUDIN-4 EXPRESSION IS ASSOCIATED WITH DISEASE FREE SURVIVAL IN BREAST CARCINOMA IN SITU: MEAN FOLLOW UP OF 8.2 YEARS

Giualino Mendes Duarte, Natalie Rios Almeida, Tamara Pinto de Oliveira Araujo, Fernando Tocchet, Juliana Espinola, Carolina Teixeira de Resende Barreto, Fernando Augusto Soares, Geisilene Russano de Paiva Silva

Introduction: Claudins are tight junction molecules that have been associated with breast cancer prognosis. The claudin-low intrinsic subtype of invasive carcinoma was recently described and associated with high grade carcinoma, low junction molecules expression and worse response to chemotherapy. However, it is not known whether the expression of claudins may provide clues as to carcinoma in situ prognosis. The aim of study was evaluate the association between claudin–4 expression and disease-free survival and histologic type of local recurrence in carcinoma in situ after longer follow up. Methods: A tissue microarray (TMA) block was constructed from 137 pure carcinoma in situ paraffin blocks sampled from patients treated from 1999 to 2009. The TMA was submitted to immunohistochemical staining for claudin-4. A claudin-4 score calculated based on percentage and intensity of expression, categorized samples as: claudin-4-low or claudin–4-high. Clinical data, treatment data, local recurrence data and survival of each patient were reudin-4; Carcinoma Ductal In Situ; Diasease-free survival; Local recurrence.analyzed from medical records. Kaplan-Meier curves, log-rank and Wilcoxon tests were used to analyze disease-free survival; qui-square and Fisher test were employed to compare others variables; a significance level of 5 % was used.Results: Claudin-4 expression was evaluated in 86 samples, 88.4% were claudin-4-high and 11.6% claudin-4-low. Mean follow up was 8.2 years ( and local recurrence rate was 10.5 %. There was significant difference in the disease-free survival between claudin-4-high and claudin-4-low (4.9 x 1.9 respectively, p= 0.02); however there was no difference between both in histologic type of recurrence, invasive or in situ (p=0.44). Conclusion: In our samples, claudin-4-high expression in carcinoma in situ was more frequent than low expression. Our data showed that claudin-4-low expression had a worse prognosis in carcinomas in situ (inferior disease-free survival) but it was similar to claudin-4-high in histologic type of local recurrence.