Staging is the process the doctors go through to work out whether your cancer has spread to another part of the body.
Conjunctival melanoma is staged using a system called TNM (Tumour, Nodes, Metastasis). The tumour is assessed for its size and position, and whether it has spread to surrounding areas. Scans may be needed of the head and neck.
As conjunctival melanoma can spread through the lymphatic system, thel ymph nodes are assessed by clinical examination, scanning and maybe sentinel lymph node biopsy.
Conjunctival melanoma can also spread through the bloodstream, so scans are usually used to check the most common sites of metastases – lung, liver, brain and bone.
An MRI of the head and neck may be ordered to see if the melanoma has spread to the surrounding area. There may be a wait for the scan itself and for the results.
If lymph node spread is identified, further investigations will be undertaken to identify any distant spread.
An X-ray may be performed on the chest to check for lung metastases. It is a good staging tool as results can be given on the same day. If doctors see something suspicious on the film they are likely to order a more sensitive test such as a CT scan.
The head and neck MRI lasts about 45 minutes. You lie on your back and a mask and neck brace is put on. You have contrast dye injected in your arm for the last 15 minutes of scan. You can listen to music in earphones if you choose as it gets very noisy. – Sheila Koszary
An ultrasound may be performed on the neck. If lymph node spread is identified, further investigations will be undertaken to identify any distant spread.
The advantage of ultrasound is the speed at which results can be known, so it makes a good staging scan. Usually if an ultrasound scan comes back as suspicious in some way, a more detailed scan will be ordered. The disadvantage of ultrasound is that the scan itself is not saved, so future scans cannot be compared.
A CT scan is a series of X-rays taken from different angles, and put together by computer for a detailed picture. It can be a good way of finding lung and bone metastases, however, it does involve radiation so it may be more suited to staging than follow up. CT scans are not recommended for detecting liver metastases
Some centres may have PET-CT scans available. This scan is like a CT scan, but with the addition of a small amount of a radioactive drug injected into the patient. This gives very detailed information about how the tissues in the body are working.
Blood tests are now accepted to be of little use in screening for ocular melanoma metastases, however, you are still likely to have blood tests as part of your general work up at diagnosis.