The Smad4/PTEN Expression Pattern Predicts Clinical Outcomes in Colorectal Adenocarcinoma

Background Smad4 and PTEN are prognostic indicators for various tumor types. Smad4 regulates tumor suppression, whereas PTEN inhibits cell proliferation. We analyzed and compared the performance of Smad4 and PTEN for predicting the prognosis of patients with colorectal adenocarcinoma. Methods Combined expression patterns based on Smad4+/– and PTEN+/– status were evaluated by immunostaining using a tissue microarray of colorectal adenocarcinoma. The relationships between the protein expression and clinicopathological variables were analyzed. Results Smad4–/PTEN– status was most frequently observed in metastatic adenocarcinoma, followed by primary adenocarcinoma and tubular adenoma (p