Mutational analysis of KRAS, BRAF, and TP53 genes of ovarian serous carcinomas in Korean women.
OBJECTIVE
To assess the prevalence of KRAS, BRAF, and TP53 mutations in cases of low-grade and high-grade serous carcinomas and to evaluate the clinical outcomes of these morphologically distinct carcinomas.


METHODS
Patients with primary invasive serous carcinomas were classified according to the universal grading system. Grade 2 serous tumors were excluded. A total of 100 patients were included for clinical evaluation. Thirty-seven patients, including 20 with low-grade and 17 with high-grade carcinomas, were selected for mutational analysis.


RESULTS
The low-grade carcinoma group was characterized by young age and premenopausal period compared with the high-grade carcinoma group, but there were no statistically significant differences in stage, metastasis of lymph node and residual disease. There were no statistically significant differences in survival rates, however, the low-grade carcinoma group showed a trend for improved progression-free survival compared with the high-grade carcinoma group of early stage (p = 0.064). Mutations in KRAS and BRAF were found in 6 (30%) and 2 (10%) patients in the low-grade carcinoma group, respectively, however, they were not found in the high-grade carcinoma group. KRAS and BRAF mutations were mutually exclusive, and both mutations were observed in 40% (8/20). The frequency of TP53 mutations in low-grade and high-grade carcinoma groups were found in 20% (4/20) and 70.6% (12/17), respectively (p = 0.009).


CONCLUSIONS
Low-grade serous carcinoma shows mutation pattern different from that with high-grade carcinoma. As there were no significant differences in stage distribution and survival, especially in advanced stage, we suggest that more studies are needed to segregate these patients into distinct disease entities.
Department of Obstetrics and Gynecology, College of Medicine, University of Ulsan, Asan Medical Center, Songpa-Gu, Seoul, Korea.
Yun-Hyun
YH
Cho
Dae-Yeon
DY
Kim
Jong-Hyeok
JH
Kim
Yong-Man
YM
Kim
Kyu-Rae
KR
Kim
Joo-Hyun
JH
Nam
Young-Tak
YT
Kim
D000328:Adult; D018284:Cystadenocarcinoma, Serous / Q000235:genetics*; D004252:DNA Mutational Analysis; D005260:Female; D006801:Humans; D008875:Middle Aged; D010051:Ovarian Neoplasms / Q000235:genetics*; D011518:Proto-Oncogene Proteins / Q000235:genetics*; D048493:Proto-Oncogene Proteins B-raf / Q000235:genetics*; D016283:Proto-Oncogene Proteins p21(ras); D018631:ras Proteins / Q000235:genetics*
C117307:KRAS protein, human; D011518:Proto-Oncogene Proteins; C482119:BRAF protein, human; D048493:Proto-Oncogene Proteins B-raf; D016283:Proto-Oncogene Proteins p21(ras); D018631:ras Proteins