Frozen section diagnosis of ovarian epithelial tumours: a practical guide for pathologists

The most common indication for frozen section at our Centre (NGOC, Gateshead, UK) is for the diagnosis of ovarian masses. The other indications are to assess the nature of uterine masses, assess adequacy of resection margins in trachelectomy specimens and assessment of lymph nodes for metastases prior to extensive surgical procedures such as pelvic exenterations and laterally extended endopelvic resections. This article will focus on practical issues relating to ovarian epithelial tumours, the most frequent group of tumours submitted for frozen section diagnosis. It will provide guidance on the approach to common entities, diagnostic pitfalls, and strategies for dealing with less frequently encountered lesions. Emphasis will be placed on macroscopic examination, appropriate sampling, and the use of intraoperative cytology as an adjunct. The aim is to provide clinically useful frozen section diagnosis in order to reduce the number of diagnoses deferred to paraffin section and facilitate optimal intraoperative management decisions.