Abstract :
Background: The proposed histopathological precursor lesions of high grade ovarian serous tumors are Secretory Cell OUT growth (SCOUT) and Serous Tubal Intraepithelial Carcinoma (STIC) in fallopian fimbriae. P53 signature in fimbriae is considered as immunohistochemical precursor lesion. This study compared the p53 expression pattern of serous tumors and their fallopian tubes to explore their relationships.
Aim: To study the histopathological changes in fallopian fimbriae of ovarian serous tumors with p53 expression pattern.
Materials and Methods: A cross-sectional study of 90 cases of serous ovarian tumors were done. (61benign, 6 borderline and 23 malignant). Their fallopian tubes were examined as per SEE-FIM PROTOCOL. P53 expression pattern of serous tumors and fimbriae were analyzed using SPSS software version 20.
Results: Among the 90 cases, SCOUTs were distributed in all categories of serous tumors and 59% of them were in nonmalignant tumors. Only 22.4% of SCOUTs showed p53 signature. STIC were distributed more in high grade tumors (66.6%) and were absent in benign tumors. All the STICs showed aberrant p53 expression pointing mutant p53 gene. Aberrant p53 pattern was high in high grade tumors (91.6%) compared to benign, borderline, low grade tumors (0%, 16.7%,18.2%).
Conclusion: STIC and p53 signatures were common in high grade serous carcinoma and their fallopian tubes. SCOUT was present both in benign and malignant tumors but p53 signature was low. Hence it can be presumed that SCOUT is an initial event, later progressing through p53 positive STICs leading to high grade serous carcinoma in ovaries.
Keyword :
P53 signature, SCOUT, Serous tumors, STIC.