What is Gorlin syndrome?
Gorlin syndrome is a medical condition caused by a fault in one of the thousands of genes which humans possess.
Gorlin syndrome is a rare condition that affects many areas of the body and increases the risk of developing various cancerous and noncancerous tumours.
Gorlin syndrome
It’s official: Gorlin syndrome is the name of our condition. It’s not Gorlin’s syndrome, Gorlin-Goltz syndrome, NBCCS, BCNS – it’s Gorlin syndrome!
World Health Organisation
The World Health Organisation runs the International Classification of Diseases (ICD). Every 5 years ICD issues an official list of disease names and definitions. ICD 11 is going live later in 2019 and it’ll be another 5 years before ICD12 comes out in 2024.
For the first time, ICD has recognised Gorlin syndrome as a disease and linked it into the ICD system. All the other names should no longer be used.
Importance of the WHO classification
ICD chose the name Gorlin syndrome for two reasons. First of all, it’s easier to remember than some of the other names. Secondly, some of the other names (for example BCNS) only refer to skin, suggesting that having Gorlin syndrome doesn’t affect other parts of the body.
It should help improve the way health services are planned. For example, if you asked the NHS in London how many people in England had Gorlin Syndrome, it probably couldn’t say just now. This is because hospitals and doctors across the country may use different names for the same thing. Now everyone should be using the same name and ICD code. In a couple of years it should, for the first time, be able to say how many people have been diagnosed with Gorlin syndrome in any given area. Trying to compare accurate figures about Gorlin syndrome across countries has been even trickier, up to now.
It’s just the start though…. The entry does not yet describe all the different ways people with Gorlin syndrome can be affected. It also needs to be linked to the two different gene mutations, PTCH1 and SUFU, which cause slightly different types of Gorlin syndrome. ICD11 is a great start and we now have 5 years to improve this achievement.
Gorlin Syndrome & the skeletal system
The Gorlin syndrome gene has an effect on the development of the skeletal system. This does not progress throughout life and usually causes no ill effects as all.
Principally affected are the height, the shape of the ribs, the shape of the bones in the vertebral column, and the shape of the skull.
People with Gorlin syndrome can be much taller than expected for their family.
The shape and size of the skull is usually larger than average (usually over 60 cm in adults) – some people have difficulty in gettings hats. The front of the skull and the forehead may be very prominent, the bone being especially protruberant (swelling or bulge) above and over the outer parts of the eyes (this is called ‘frontal and parietal bossing’). A large proportion of babies with Gorlin Syndrome require delivery by Caesarian Section because of the large head size.
Reviewed and verified by Medical Advisers in conjunction with the Gorlin Syndrome Group, October 2022.
Basal Cell Carcinomas
90% of individuals with the syndrome will develop basal cell carcinomas (BCC) at some stage in their life.
BCCs is the most common form of cancer in the general population. BCCs in members of the general population are associated with excess exposure to the sun, and therefore appear on the sun exposed parts of the body, usually the face. In Gorlin syndrome the BCCs can also occur on other areas of the body which have not been exposed to the sun.
More about Basal Cell Carcinomas
Brownish/pink/orange basal cell nevi may occur in early childhood and may lie quiescent (dormant) without aggressive behaviour. The histologic appearance is that of a typical BCC which, when excised, can be the first unexpected finding of Gorlin syndrome in simplex cases (affected individuals with no family history of Gorlin syndrome, especially children.
Active BCCs may grow from existing basal cell nevi that may be numerous or typical BCCs may appear from virtually blemish free skin. BCCs may also crust, bleed, ulcerate or may present as a localised infection.
BCCs can occur in early childhood but in general do not present until the late teens or early adulthood. They occur more frequently with age, although 10% of individuals with Gorlin syndrome never develop a BCC. Individuals with type 1 skin (white skin that burns but never tans) and individuals with excessive ultraviolet light exposure seem especially prone to developing large numbers of BCCs.
The areas around the eyes, nose, cheek bones and the upper lip are the most frequently afected sites on the face. Usually only a few become aggressive, when they are locally invasive and behave like ordinary BCCs. Evidence of aggressive transformation of an individual lesion includes an increase in size, ulceration, bleeding, or crusting. Some patients can develop aggressive BCCs without first developing naevi.
Features
There are many features which may occur in Gorlin syndrome, although most are rare. Some of the features are listed below.
Ophthalmic problems – in one study, ophthalmic problems affected 26% of people with the syndrome. They include squint (convergent strabismus), nystagmus, cataracts and underdevelopment of the eye (microphthalmia).
Cleft lip and palate – about 5% of people with the syndrome have cleft lip and palate.
Ovarian fibromas – calcified ovarian fibromas have been reported in about 20% of females with the syndrome and may be mistaken for calcified uterine fibroids. They may cause torsion of the ovary (twisting which can result in blocking of blood supply) but are not thought to affect fertility. They can become large and calcified, however, malignant transformation is rare and has only been reported after radiotherapy.
Medulloblastoma – about 5% of individuals with the syndrome develop the childhood brain malignancy medulloblastoma. Peak incidence in Gorlin syndrome is in the first two years of life. Treatments are available and there is a favourable prognosis compared to other medulloblastoma patients.
The risk of other malignant tumours is not clearly increased.
Reviewed and verified by Medical Advisers in conjunction with the Gorlin Syndrome Group, October 2022.