Document Type : Original Research


1 Cancer Molecular Pathology Research Center, Mashhad University of Medical Sciences, Mashhad, Iran.

2 Department of Surgical and Clinical Pathology, Faculty of Medicine, Mashhad University of Medical Sciences, Mashhad, Iran

3 Department of Pathology, Faculty of Medicine, Mashhad University of Medical Sciences, Mashhad, Iran

4 Department of Pathology, Mashhad University of Medical Sciences, Mashhad, Iran

5 Cancer Molecular Pathology Research Center, Department of Hematology and Blood Bank, Mashhad University of Medical Sciences, Mashhad, Iran

6 Department of Medical Genetics, School of Medicine, Yazd University of Medical Science, Yazd, Iran

7 Cancer Molecular Pathology Research Center, Mashhad University of Medical sciences, Mashhad, Iran

8 Cancer Molecular Pathology Research Center, Faculty of Medicine, Mashhad University of Medical Sciences, Mashhad, Iran

9 Department of Hematology, School of Allied Medical Science, Iran University of Medical Sciences, Tehran, Iran


Background & Objective: Epithelial ovarian cancer (EOC) is the most prevalent type of ovarian cancer. Previous studies have elucidated different pathways for the progress of this malignancy. The mutation in the B-Raf proto-oncogene, serine/threonine kinase (BRAF) gene, a member of the MAPK/ERK signaling pathway, plays a role in EOC. The current study aimed to determine the frequency of the BRAF V600E mutation in ovarian serous and mucinous tumors, including borderline and carcinoma subtypes.
Methods: A total of 57 formalin-fixed paraffin-embedded samples, including serous borderline tumors (SBTs), low-grade serous carcinomas (LGSCs), high-grade serous carcinomas (HGSCs), mucinous borderline tumors (MBTs), and mucinous carcinomas, and 57 normal ovarian tissues were collected. The BRAF V600E mutation was analyzed using polymerase chain reaction (PCR) and sequencing.
Results: While 40% of the SBT harbor BRAF mutation, we found no BRAF mutation in the invasive serous carcinoma (P=0.017). Also, there was only 1 BRAF mutation in MBT and no mutation in mucinous carcinomas. In addition, we found no mutation in the control group.
Conclusion: The BRAF mutation is most frequent in borderline tumors but not in invasive serous carcinomas. It seems that 2 different pathways exist for the development of ovarian epithelial neoplasms: one for borderline tumors and the other for high-grade invasive carcinomas. Our study supports this hypothesis. The BRAF mutation is rare in mucinous neoplasms.


Main Subjects

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