p53 protein accumulation as a prognostic marker of preoperative radiotherapy and/or chemotherapy in advanced squamous cell esophageal carcinoma - preliminary report

The correlation between immunohistochemical detection (IH) of p53 protein a nd tumor response to preoperative chemotherapy and/or radiotherapy in advan ced esophageal squamous cell carcinoma was evaluated. Fifty-six patients wi th advanced esophageal squamous cell carcinoma were included in the study. All patients were staged and diagnosed microscopically before treatment. Pa tients were divided into three groups: 17 patients treated with chemotherap y and radiotherapy preoperatively (group I) (cisplatin and 5-fluorouracil, cobalt-60 therapy; total dose 3000 Gy); 19 patients treated with chemothera py only (group II); and 20 patients who did not receive preoperative therap y (group III), The response of the tumor tissue to preoperative treatment w as evaluated macroscopically and microscopically in operated specimens acco rding to the classification: CR, complete response; PR1, major partial resp onse with regression of at least 50% of initial tumor mass; PR2, minor part ial response with regression of less than 50% of initial tumor mass. In all 56 patients immunohistochemistry was used to detect anti-p53 antibody (Dak o, DO-7) in normal mucosa and cancer tissue, The response of the tumor was similar in both group I and group II. p53 protein was not expressed in the normal esophageal mucosa, A high level of p53 in operated specimens was ass ociated with unfavorable tumor response to preoperative treatment. Therefor e, immunohistochemical detection of p53 protein can be considered to predic t the outcome of preoperative therapy.