Impact of Secreted Protein Acidic and Rich in Cysteine (SPARC) Expression on Prognosis After Surgical Resection for Biliary Carcinoma

Background Secreted protein acidic and rich in cysteine (SPARC) is a matricellular protein that influences chemotherapy effectiveness and prognosis. The aim of this study was to investigate whether SPARC expression correlates with the postoperative survival of patients treated with surgical resection for biliary carcinoma. Methods SPARC expression in resected biliary carcinoma specimens was investigated immunohistochemically in 175 patients. The relationship between SPARC expression and prognosis after surgery was evaluated using univariate and multivariate analyses. Results High SPARC expression in peritumoral stroma was found in 61 (35%) patients. In all patients, stromal SPARC expression was significantly associated with overall survival (OS) ( P = 0.006). Multivariate analysis revealed that high stromal SPARC expression was an independent risk factor for poor OS (HR 1.81, P = 0.006). Moreover, high stromal SPARC expression was independently associated with poor prognosis in a subset of 118 patients treated with gemcitabine-based adjuvant chemotherapy (HR 2.04, P = 0.010) but not in the 57 patients who did not receive adjuvant chemotherapy ( P = 0.21). Conclusions Stromal SPARC expression correlated with the prognosis of patients with resectable biliary carcinoma, and its significance was enhanced in patients treated with adjuvant gemcitabine-based chemotherapy.