OBJECTIVETo investigate the predictive value of P53, Ki-67, HER2 protein detection in neoadjuvant chemotherapy for adenocarcinoma of gastroesophageal junction (AGEJ).

METHODSPreoperative biopsy specimens and clinical data of 72 patients of locally advanced Siewert II AGEJ between June 2010 and December 2013 were reviewed. All the patients received SOX scheme neoadjuvant chemotherapy, and were divided into effective group (complete response plus partial response) and ineffective group (stable disease plus progressive disease). Expressions of above 3 proteins were detected by immunohistochemistry in all the patients before neoadjuvant chemotherapy. The relationship between various proteins and efficacy of chemotherapy was analyzed by univariate and logistic multivariate regression analyses.

RESULTSAll the 72 patients successfully completed 2 cycles of SOX neoadjuvant chemotherapy, among them, 5 cases (6.9%) with complete response, 30 cases (41.7%) with partial response, 31 cases (43.1%) with stable disease, 6 cases (8.3%) with progressive disease, including 35 cases in effective group and 37 cases in ineffective group. Compared with ineffective group, the positive expression rate of P53 was significantly reduced (25.0% vs. 45.9%, P=0.020), and that of Ki-67 significantly increased (77.1% vs. 43.2%, P=0.003), however, there was no significant difference in the expression rate of HER2 between the two groups (P>0.05). Multivariate analysis showed that Ki-67 was the independent predictive factor for the efficacy of neoadjuvant chemotherapy (P=0.015). Spearman rank correlation showed that Ki-67 expression was positively correlated with HER2 expression (r=0.259, P=0.028), but P53 expression was not correlated with Ki-67 or HER2 (r=0.140, 0.042, P=0.240, 0.725, respectively).

CONCLUSIONSSOX neoadjuvant chemotherapy is safe and effective for AGEJ, especially for patients with depressed expression of P53 and elevated expression of Ki-67, which both may be used as reference for the prediction of chemotherapy efficacy. There is no correlation between P53 and Ki67 proteins, so combined detection may improve the predictive value.