BCL2 and papillary serous cystadenocarcinoma: More than 50% of the epithelial cells stained positive for Bcl-2 in 67% (2/3) of well differentiated carcinomas (WD), 33% (2/6) of moderately differentiated serous papillary carcinomas (MD), and 21% (4/19) of poorly differentiated serous papillary carcinomas (PD) (Table 2, Figure 2).