Various types of skin cancer lesions can only be positively diagnosed by performing a biopsy which will determine the depth of the tumour and if the tumour is non malignant or malignant. There are various different biopsy methods such as the shave method which is the most common form of biopsy whereby the doctor shaved off the abnormal growth with a thin sharp blade when the doctor suspects a squamous cell carcinoma or basal cell carcinoma. Then there is an incision biopsy whereby the doctor removes part of the growth using a scalpel. Another method is a punch biopsy where a circle of tissue is removed using a sharp hollow instrument.

However when a doctor suspects a melanoma, they will then perform a total excision biopsy whereby the entire growth and surrounding tissue is removed using a scalpel, and the specimen is then sent to the labs for skin diagnoses. However, it may not always be possible to remove the tumour as it will primarily depend on the location and the size. These types of procedures are carried out in an outpatient clinic or in the doctor office under local anaesthetic. The skin tissue is examined under a microscope by a pathologist who will be able to define what type of skin cancer the patient is dealing with. If the doctor on the other hand suspects a metastasis melanoma, then the person will have to undergo blood tests to check their LDH levels and also have a MRI, CT and PET scan done as well as chest x-rays to establish the staging and diagnosis. Many doctors will also take a sample of the lymph nodes by performing a fine needle aspiration or by means of sentinel lymph node mapping. If the biopsies reveal that the person has a melanoma, then the doctor will have to establish the stage of the disease in order to plan the treatment protocol effectively. Staging is based on three separate factors which include the size of the growth, the depth and whether or not this has spread to the surrounding lymph nodes or to any other part of the body.

The stages of a melanoma include stage 0 which is known as melanoma in situ and involves the top layer of the skin only. Then Stage I is when the melanoma is less than 2mm deep, Stage II is when the melanoma is more than 2mm deep, Stage III means the carcinoma has already spread to the bone, muscle, cartilage and possibly to the lymph nodes and not to any other parts of the body. The final stage is IV whereby the cancer has already spread to various organs and other places in the body.