The expression of proliferating cell nuclear antigen, p53, p21, and apoptosis in primary gastric lymphoma

Background. We have investigated the correlations among the expression of proliferating cell nuclear antigen (PCNA), p53, p21, and the prognosis of primary gastric lymphoma, and we have investigated apoptosis by using transferase mediated deoxyuridine triphosphate nick-end labeling staining. Methods. A retrospective study was performed on 33 cases of primary gastric lymphoma that were surgically resected. Histopathologic examination was undertaken according to the Working Formulation classification. Immunohistochemical staining was performed by using the avidin-blotin-peroxidase complex method, with anti-PCNA antibody, anti-p53 antibody, and anti-p21 antibody. Apoptosis was quantified in situ from paraffin-embedded specimens by using an apoptosis detection kit. Results. On histologic grade, the survival rate of high-grade type was significantly lower than that of low-grade type and than that of intermediate grade type. The PCNA index of low-grade type was significantly lower than that of intermediate-grade type and than that of high-grade type. Those patients who experienced recurrence were both p53(+) and p21(-). Two of these patients were receiving postoperative chemotherapy but nevertheless experienced recurrence (it 18 months and at 5 months after surgery. The PCNA index of p53(+) p21(-) cases was significantly higher than that of p53(-) p21(+) cases. The apoptotic count of p53(-) p21(+) cases was significantly higher than that of p53(+) p21(-) cases. Conclusions. The Working Formulation classification and the PCNA index were each significant factors predicting the prognosis of primary gastric lymphoma. The prognosis of p53(+) p21(-) cases was poor, and the apoptotic count of p53(+) p21(-) cases was low. According), the effect of combined chemotherapy for those cases was thought to be poor.