Sex cord tumours of ovary – information pack

Also known as:

  • Sex cord stromal tumours
  • SCSTs

Classification Code ICD C56

These rare ovarian tumours have many different subtypes, each with a specific name. Some are benign (non-cancerous) and some are malignant (cancerous). These include fibromas, thecomas, granulosas and Sertoli-Leydig tumours.


How rare are sex cord tumours?

In the UK and Europe the usual definition of a rare cancer is one that occurs in less than 6 people out of every 100,00 each year. Because there are around 200 rare cancers, this means that they make up about 24% (nearly a quarter) of all cancers.

The total incidence of all sex cord tumours is 0.13 cases per 100,00 women. This makes up around 5-7% of all ovarian cancers with around 85 cases a year in the UK. The most common malignant type is the granulosa cell tumour. The granuloma type is more common in women aged 50-55 whilst other types are more often seen in younger women.

What are sex cord tumours?

What is the sex cord?

When an embryo is developing, groups of cells start to specialise to eventually form all the different cells and tissues that make up a human body. One of these groups of cells is called the sex cord. It eventually forms cells that fill the space in an ovary. They surround and support the egg cells and follicles that develop when an egg is about to be released. This collection of cells and the connective tissue they are found in is called the stroma.

There are different types of ovarian sex cord stromal tumours (SCSTs). These can be non cancerous (benign) or cancerous (malignant). Granulosa cell tumours are the most common type.

What are sex cord stromal tumours?

Any abnormal growth in the body is described as a tumour. These can be non-cancerous (benign) or cancerous (malignant). If the tumour started in stromal cells that came from the sex cord they are called sex cord stromal tumours (or sometimes sex cord tumours or SCSTs for short). There are several types of cells that make up the sex cord stroma and tumours are named according to which type of cell they form from.

Types of sex cord stromal tumours

There are 3 main groups of SCSTs

  • pure stromal tumours including fibromas, thecomas and sclerosing stromal tumours
    • These come from mature ovary tissue
  • pure sex cord tumours including granulosa cell tumours
    • These come from the remaining early cells from the development of the ovary
  • mixed sex cord stromal tumours including Sertoli–Leydig cell tumours
    • These come from cells from both types of tissue.


Most pure stromal tumours are non cancerous (benign). Sertoli-leydig tumours can be either benign or cancerous. The most common type of SCST are granulosa cell tumours which are cancerous (malignant).

Granulosa cell tumours of the ovary

There are 2 types of granulosa cell tumours:

  • adult granulosa cell tumours are the most common type and are found in middle age and older women
  • juvenile granulosa cell tumours are rarer and usually develop before puberty

Granulosa cell tumours can show extra symptoms beyond abdominal pain, bloating and constipation because they also produce hormones. The extra oestrogen can cause symptoms such as abnormal or heavy vaginal bleeding, breast tenderness or early puberty.

What are the current treatment options?


This is the normal first action to remove as much of the tumour as possible. Surgery might include removing the whole ovary or trying to preserve fertility if the patient plans on having children.


This might be given after surgery if the tumour has spread into the abdomen or if it recurs. Standard chemotherapy drugs are generally used in combinations of bleomycin, etoposide, cisplatin, carboplatin and paclitaxel.

Some studies have been made of hormonal therapy or targeted therapy with drugs such as imatinib for recurrent or advanced disease. Although findings have been positive, patient numbers have been too small to be conclusive.


Radiotherapy is generally only used after recurrence.

What are the current clinical trials?

As of 23-1-23 there are no specific clinical trials running in the UK. They will be added as we hear of them.

Where can I find support groups?





Support and information for women with all ovarian cancers. Includes a support group for rare cancers.

The Eve Appeal

Support and information for women with all ovarian cancers. Includes a support group for rare cancers.

Incidence data for sex cord tumours of the ovary

Table of Incidence Data (may not be complete)

RareCare list

Other estimates

Links to alternative data source

Incidence (per 100,000)


UK incidence (per annum)


8,250 (15% of total of 55,000)

UK prevalance


Europe prevalance


US prevalance*


*estimate based on assumption that US population is ~5x UK


Age range affected

Gender balance


Ethnicity data

Incidence data may not be complete.

Incidence per 100,000 – 12

UK incidence per 100,000 – 

UK Prevalance – 

Europe prevalance – 

US prevalance (estimate based on assumption of ~5x UK population) – 

Link to alternative data source – Cancer Research UK

Age range affected – more common under 40

Gender balance – predominantly women but does occur in men

Ethnicity data – more common in black women (