Medical terminology is often confusing and can be difficult to understand, especially when you’re going through stressful investigations. The staff at The Colposcopy Unit will always try to speak in plain English and take time to answer your questions and address any concerns.

What is CIN?

CIN stands for Cervical Intra-epithelial Neoplasia. It refers to pre-cancerous changes in the cervix that have been seen on colposcopy examination. These changes can also be known as dysplasia or SIL, which stands for Squamous Intraepithelial Lesions. Thomas Ind, consultant gynaecologist at The Colposcopy Unit often describes CIN in more simple terms: ‘Cervix; In the skin; New cells’.

CIN is used to classify abnormal cells that are found during colposcopy. It is graded numerically according to how deep into the cervix the cell changes extend.

CIN 1: The abnormal cells extend through a third of the depth of the surface of the cervix.

CIN 2: The abnormal cells are in two-thirds of the thickness of the cervical membrane.

CIN 3: The cells go the whole way through the area.

CIN causes no symptoms, so changes can be happening in your cervix without you being aware. That’s why it’s very important for women to have regular smear tests.

Why is discovering CIN important?

The pre-cancerous cell changes of CIN have the potential to develop into cancer. However, cancer development is not inevitable. It’s   possible for CIN to resolve spontaneously without any treatment.

The higher the number, the greater the risk is of cancer developing if the abnormal cells aren’t removed. The problem is, it’s impossible to predict which woman’s CIN will go away untreated and which woman’s CIN will progress to cervical cancer. So, it is better to be cautious.

The minor changes of CIN 1 often go away without treatment, so it can be safe to monitor the cervix over time. CIN 2 and CIN 3 are less likely to resolve spontaneously and there is a greater risk of them progressing to cancer, so Mr Thomas Ind will usually offer you treatment to prevent this happening.

Does CIN mean I’ve got cancer?

CIN is not cancer, but it has the potential to develop into cancer if it is not monitored carefully and treated appropriately. CIN 3 is sometimes also known as carcinoma-in-situ, which does sound like cancer- but it is not the same thing. Cervical cancer extends deeper into the cervix. Removal of any abnormal cells at an early stage can prevent this happening.

Not all CIN needs treatment, it often goes away on its own. However, at The Colposcopy Unit, we recommend treatment for CIN 2 and CIN 3. The good news is that treatment is straightforward and effective. Ninety-five percent of women are cured by their first treatment, others may need repeated therapy and monitoring.

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