Assessment of the predictive value of clinical and histopathological factors as well as the immunoexpression of p53 and bcl-2 proteins in response to preoperative chemotherapy for esophageal squamous cell carcinoma.

The aim of the study was to determine the predictive value of selected clinical and histopathological factors as well as the immunohistochemical expression of p53 and bcl-2 proteins in the prediction of the pathological response to preoperative chemotherapy in esophageal squamous cell carcinoma. Thirty-four patients with advanced squamous cell carcinoma of the thoracic esophagus (T2-4 N0-1 M0), who underwent one cycle of cisplatin and 5-fluorouracil therapy followed by subtotal esophagectomy, were studied. All clinical factors (tumor longitudinal diameter in a computed tomographic scan, invasion depth, the presence of lymph node metastasis and clinical tumor staging) were evaluated before the onset of the therapy. The histopathological features (grade of differentiation, degree of keratinization, nuclear polymorphism, mitotic index, pattern of cancer invasion and inflammatory response), and the expression of p53 and bcl-2 proteins were also estimated in prechemotherapy endoscopic biopsy specimens. Pathological response to chemotherapy was assessed in surgically resected specimens. Of 34 patients, two (5.9%) showed complete response (CR), six patients (17.6%) exhibited major histological changes (partial response 1; PR1), 24 (70.6%) showed minor histological changes (partial response 2; PR2), and two patients (5.9%) exhibited no response to chemotherapy (stable disease; SD). There were no significant relationships between the response to preoperative chemotherapy (CR + PR1 vs. PR2 + SD) and the majority of the clinical and all the histopathological features. Deeper cancer invasion before chemotherapy was the only factor that tended to worsen the therapy effect (p < 0.01). The pathological response to treatment had no significant associations with the expression of p53 and bcl-2 proteins in esophageal squamous cell carcinoma. It should be noted, however, that both patients in CR were p53 and bcl-2 protein-negative.