The primary retroperitoneal serous adenocarcinoma (PRSAC) is a rare malignant tumor of the retroperitoneum. It shares the same pathological and biological behavior with ovarian serous carcinoma. Most of the cases develop as peritoneal adenocarcinoma and rarely occur in the retroperitoneum. It is reported as serous surface papillary carcinoma of the peritoneum and extraovarian peritoneal serous papillary carcinoma. We present a case of PRSAC in a 60-year-old woman. Only 11 cases of PRSAC have been reported from 1983 to 2019. Histopathological features with immunohistochemical expressions are important to diagnose PRSAC. The outcome and survival mainly depend on the possibility of surgical resection. Molecular genetics of PRSAC should also be studied in relation with its ovarian counterpart.
The objective of this study is to assess tissue expression of CA-125 and HE4 protein in primary benign and malignant epithelial tumours of the ovary and correlate with serum CA-125 levels. A total of 100 formalin-fixed, paraffin embedded sections of ovarian tumours which included serous adenoma (11), mucinous adenoma (42), serous carcinoma (20), mucinous carcinoma (12) and endometrioid carcinoma (15), histologically diagnosed between 1st January 2004 to 31st December 2012 at the University Malaya Medical Centre, were stained for HE4 (rabbit polyclonal antibody, Abcam, UK) and CA-125 (mouse monoclonal antibody clone: OC125, Cell Marque Corporation, Rocklin, California, USA). Pre-operative serum CA-125 levels were obtained from the laboratory information system. Immunoscore (I score) for HE4 and CA-125 was given based on the intensity of staining and percentage of positive tumour cells and considered significant when it was >50 (intensity of staining multiplied by percentage of positive tumour cells). Serum CA-125 levels were compared with the I score of HE4 and CA-125 in tissues. We noted that the CA-125 levels in serum and tissues were significantly raised in malignant compared to benign ovarian tumours (p value<0.05). Tissue expression of HE4 protein was also significantly raised in malignant tumours compared to benign tumours (p value<0.05). We conclude that HE4 can be a useful tissue immunomarker in addition to CA-125.