p53 and HER-2/neu overexpression in ovarian borderline tumors

Objective: To study p53 and HER-2/neu expression in borderline ovarian tumors (BLOT) by assessing their frequency, coexpression, and relationship to histologic type, FIGO stage, tumor recurrence, and survival. Methods: Forty-two patients with confirmed BLOT (25 serous, 13 mucinous, and 4 seromucinous) were followed for 1.5 to 14 years (mean, 6.3). Thirty (71%) patients had FIGO stage I and 12 (29%) had FIGO stage III disease. Paraffin-embedded sections from the 42 BLOT, 5 normal ovaries, and 10 benign ovarian cystadenomas were stained using monoclonal antibodies against human p53 (DAKO-p53, DAKO, Denmark) and HER-2/neu (C-erB-2, Triton, Parkway, CA). Positive staining was semiquantitated depending on the number of positively stained tumor cells. p53 and HER-2/neu overexpressions were correlated to each other, to histologic subtype, stage, tumor recurrence, and survival. Results: None of the patients had tumor recurrence. The 5- and 10-year disease-free survival was 100%. None of the normal ovaries or ovarian cystadenomas demonstrated overexpression of p53 or HER-2/neu. Ten (24%) BLOT demonstrated overexpression of p53 and 9 (21%) demonstrated overexpression of HER-2/neu. HER-2/neu overexpression was significantly greater in stage III than in stage I tumors (P = 0.0157). Seromucinous BLOT demonstrated significantly greater p53 overexpression compared with other histologic subtypes (P = 0.030). Coexpression of p53 and HER-2/neu occurred in 4 patients (9.5%). There was no significant correlation between the overexpression of p53 and HER-2/neu (P = 0.180) and no significant relationship between p53 and HER-2/neu overexpression and the presence of microinvasion, ability to perform optimal cytoreductive surgery, tumor recurrence, or survival. Conclusions: p53 and HER-2/neu overexpression occurred in about 20-25% of BLOT overall and more commonly in seromucinous and advanced stage tumors. Coexpression occurred in 9.5% of the cases with no significant correlation between the expression of p53 and HER-2/neu. (C) 1997 Academic Press.