TY - JOUR T1 - EP1274 Distribution of histopathology types in stage 1A ovarian cancer JF - International Journal of Gynecologic Cancer JO - Int J Gynecol Cancer SP - A643 LP - A643 DO - 10.1136/ijgc-2019-ESGO.1280 VL - 29 IS - Suppl 4 AU - F Kokka AU - R Xiong AU - N Singh AU - N Kamel AU - D Oram AU - A Olaitan AU - A Nordin Y1 - 2019/11/01 UR - http://ijgc.bmj.com/content/29/Suppl_4/A643.abstract N2 - Introduction/Background Epithelial ovarian cancer (EOC) is the 6th most common cancer among women in the UK (2014). It has the highest mortality of all gynaecological cancers. More females with a known stage are diagnosed at a late stage (55–58% are diagnosed at stage III or IV), than an early stage (42–45% are diagnosed at stage I or II).It is increasingly recognized that the distribution of histopathology types of EOC differs between early and late stages.The objective of this study was to identify the distribution of the histopathology types of stage 1A EOC cases in three cancer centers in the UK and compare the results with the available published data.Methodology We identified retrospectively over a 7-year period stage 1A ovarian cancer patients who underwent primary surgical treatment in two cancer centers. We then compared the results with similar data from another cancer center over a 10-year period.Results 105 patients in total with surgical stage 1A EOC were treated at three different gynaecological cancer centers over a period of 7–10 years. In each of these centers, the majority were mucinous ovarian cancers (MOC) (54.28%, 46.15%, 36.36%), followed by clear cell/endometrioid types.Conclusion In our study the commonest type of stage 1A EOC was MOC. This may partly be due to different thresholds in diagnosing MOC, but the fact that three Centers showed a similar proportion suggests this is a true incidence. Our findings support the hypothesis that there are biological differences in the behavior of the tumor types between early and advanced EOC. MOC accounts for approximately 3% of all ovarian cancers with recent genomic studies suggesting it is a true gynaecological cancer and not a distant metastasis of a cancer that started elsewhere. Awareness of the histopathological distribution of EOC between different stages may guide screening research and aid management guidelines.Disclosure Nothing to disclose ER -