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Prognosis and survival for non-melanoma skin cancer
If you have non-melanoma skin cancer, you may have questions about your prognosis. A prognosis is the doctor’s best estimate of how cancer will affect someone and how it will respond to treatment. Prognosis and survival depend on many factors. Only a doctor familiar with your medical history, the type, size and grade of the cancer, the treatments chosen and the response to treatment can put all of this information together with survival statistics to arrive at a prognosis.
A prognostic factor is an aspect of the cancer or a characteristic of the person that the doctor will consider when making a prognosis. Prognostic factors help doctors predict a prognosis and plan treatment and follow-up.
Doctors use many of the following prognostic factors to classify basal cell carcinoma (BCC) and squamous cell carcinoma (SCC) into risk groups. The risk groups help the doctor estimate the risk that the cancer will come back (recur). Doctors also use the risk groups to help plan the best treatment.
Prognosis and survival for most non-melanoma skin cancers is excellent. The following are prognostic factors for non-melanoma skin cancer.
The location of the cancer is an important prognostic factor for non-melanoma skin cancer. Non-melanoma skin cancer on the eyelids, skin around the eyes, nose, lips, ears, scalp, fingers, toes and genitals have a higher risk of coming back (recurrence) or spreading (metastasis) than non-melanoma skin cancer in other places on the body. SCC starting in a wound or scar is also considered high risk.
Size and depth of the tumour
Non-melanoma skin cancer that is larger than 2 cm is more likely than smaller tumours to come back or to spread. A tumour that has grown deep into the layers of the skin also has a high risk of coming back and a less favourable prognosis.
Non-melanoma skin cancer that come backs after treatment has a less favourable prognosis than non-melanoma skin cancer that happens for the first time.
Type or subtype of tumour
Some subtypes of BCC and SCC tend to grow quickly.
The subtypes of BCC that have a less favourable prognosis include infiltrative, micronodular and morpheaform. The subtypes of BCC that have a better prognosis are nodular and superficial.
Desmoplastic SCC and adenosquamous carcinoma of the skin tend to come back after treatment and have a less favourable prognosis.
The grade is a description of how the cancer cells look and act compared to normal cells. Low-grade cancers have a better prognosis than high-grade cancers.
BCC with a border that is uneven has a higher risk of coming back than BCC with a border that is clear and smooth.
Cancer cells in or around nerves
Non-melanoma skin cancer that has grown into or around nerves (called perineural invasion) has a less favourable prognosis.
Immunosuppression is a weakening of the body’s immune system so it is less able to fight infections or diseases. For example, people who have had an organ transplant have a weakened immune system. People with non-melanoma skin cancer and a weakened immune system have a poorer prognosis than people without a weakened immune system. Non-melanoma skin cancer is more likely to spread to nearby lymph nodes (regional lymph node metastases) in people with immunosuppression. The cancer is also more likely to have other high-risk features, such as perineural invasion.
The lower the stage at diagnosis, the better the prognosis. Tumours that have grown deeper into the skin or have spread to nearby tissues and structures have a less favourable prognosis. Non-melanoma skin cancer that has spread to other parts of the body (called distant metastases) has a very poor prognosis.