Does the presence of endometriosis alter the behaviour of clear cell carcinoma?


Session type:

Jatinder Kaur1, Thomas Ind1, Desmond Barton1, John Shepherd1, Jane Bridges1
1Royal Marsden Hospital, London, United Kingdom


Clear cell carcinoma often occurs in association with endometriosis. The purpose of this study was to compare the characteristics of clear cell carcinomas that had arisen with or without endometriosis.


A retrospective review of histopathology reports and medical records for patients that had presented to our cancer centre for the previous 10 years was performed. Cases selected were primary clear cell carcinoma of the ovary.

Endometriosis associated clear cell carcinoma (EACC) was determined by confirmation on histology or a recorded history of endometriosis.


66 cases were identified in total, 38 were categorised EACC and 28 were clear cell carcinoma without endometriosis (CC). 

58% of the EACC group had early stage disease versus 61% in the CC group.

The rate of recurrence was 68% and 57%  and median time to recurrence was 11 months and 12 months in the EACC and CC groups respectively.

The median survival time in the EACC group was 44 months, it was 39 months for the CC group. This difference was not statistically significant (p= 0.712).


This suggests that clear cell carcinoma arising in association with endometriosis does not have differing biological characteristics or an improved survival when compared to clear cell carcinoma that has arisen de novo.