Objectives: We wish to highlight issues and controversies related to the management of borderline ovarian tumours.

Method: We present a case report of a young lady who presented to us with an ovarian cyst in pregnancy subsequently confirmed to be a borderline mucinous tumour. We further discuss regarding the diagnosis, management and long term follow up for patients with borderline mucinous tumour, highlighting controversies related to management of such patients.

Results: A literature search was performed identifying recent articles on borderline mucinous ovarian tumours. Issues pertaining to diagnosis and management are reviewed and discussed.

Conclusion: Borderline ovarian tumor presents with difficult clinical differentiation from benign and malignant lesions, requiring full histopathological examination to make a confirmed diagnosis. Conservative surgery with fertility sparing surgery and careful surgical exploration can be offered to young patients with early stage borderline ovarian tumours but are keen to maintain their fertility. Long term follow up consists of a combination of clinical examination, ultrasonography and tumour markers.