Skin Cancer Treatment: Surgery, Radiation, Immunotherapy

Skin cancer is not a single disease. The term covers several conditions that behave very differently: the non-melanoma types, mainly basal cell carcinoma and squamous cell carcinoma, and melanoma, the most serious form. Because these cancers grow at different speeds and differ in how likely they are to spread, there is no single treatment that fits all of them. What is recommended depends on the type of tumour, its size and depth, where it sits on the body and a person's general health. A great deal has changed in recent years, especially for melanoma. Surgery remains the most important treatment. Alongside it, doctors now use radiotherapy, several local treatments and modern medicines that act directly on tumour growth or on the immune system. In advanced disease these building blocks are often combined. In many hospitals a multidisciplinary team meeting decides on the treatment plan, bringing together specialists in dermatology, surgery, oncology and radiotherapy. This helps tailor the approach to each person. This article gives an overview of the common options. It is not a substitute for a conversation with your own doctor, where your personal situation comes first.

For most skin cancers, surgery is the first and often decisive step. The aim is to remove the tumour completely. The surgeon takes out not only the visible tumour but also a rim of healthy-looking skin around it, known as the margin. This is meant to make sure no tumour cells are left behind. How wide the margin is depends on the type of skin cancer and, for melanoma, mainly on how deeply it has grown. The removed tissue is then examined under the microscope. This examination confirms exactly which tumour it is and whether it was removed with a clear margin. If the tumour reaches the edge of the sample, a second operation may be needed. Small, easily reached tumours can often be removed under local anaesthetic in the clinic. In tricky areas such as the face, nose, ears or eyelids, a particularly tissue-sparing technique may be used, called Mohs micrographic surgery. The tumour is removed in stages and the edge is checked completely under the microscope until no tumour tissue remains. This helps preserve as much healthy skin as possible. For melanoma above a certain thickness, the sentinel lymph node is often examined as well, through a sentinel node biopsy. This is the first lymph node in the tumour's drainage area. If no cancer is found there, that is a good sign. The procedure is mainly used to work out the stage of the disease more precisely and to help plan further treatment.

Not every skin cancer can be removed by surgery, and surgery is not always the best route. This is where radiotherapy comes in. It uses high-energy radiation to damage tumour cells and stop them from growing. The treatment itself is painless and is usually spread over several sessions. Radiotherapy can make sense, for example, when a tumour sits awkwardly and surgery would leave a very large or disfiguring result, or when older or frail people prefer to avoid a bigger operation. It can also be added when a tumour could not be removed completely. In some situations it follows surgery to lower the risk of the cancer coming back, which doctors call adjuvant radiotherapy. In advanced melanoma, radiotherapy has a somewhat different role. Here it is used, among other things, to treat individual deposits or to ease symptoms, for instance from spread to the bones or the brain. As with any treatment, the team weighs the likely benefit against possible side effects and involves you in the decision.

Non-melanoma skin cancer, particularly basal cell carcinoma, usually grows slowly and only rarely spreads to other parts of the body. For superficial forms and for pre-cancerous changes such as actinic keratosis, gentle local treatments that do not need a scalpel are available alongside surgery. These include creams applied over several weeks that either stimulate the skin's own defences or slow cell growth. In photodynamic therapy, a light-sensitive substance is applied and the area is then treated with a special lamp, destroying the abnormal cells. Other options are freezing the tissue, known as cryotherapy, and scraping away the affected skin, known as curettage. Which method suits best depends on the type of tumour, its extent and its location. Local treatments have the advantage that they can cover larger areas and often leave little scarring. Their drawback is that, unlike surgery, they do not provide tissue for microscopic examination. That is why a reliable diagnosis beforehand and good follow-up afterwards are especially important.

Perhaps the greatest advances of recent years have come in treating advanced melanoma, and immunotherapy has been at the centre of them. The idea behind it is simple: the immune system is the body's own defence against abnormal cells, but tumour cells can slow this system down and hide from it. Immunotherapy targets exactly this weak point. The most important group of medicines are the immune checkpoint inhibitors. Checkpoints act like brakes on the immune system, normally stopping it from attacking healthy tissue. Tumours exploit these brakes for their own benefit. Checkpoint inhibitors release them, so the body's defence cells can recognise and attack the tumour again. The brake points targeted include the molecules known as PD-1 and CTLA-4. Immunotherapy is usually given as an infusion. It can also be used after a melanoma with a higher risk of recurrence has been fully removed, to lower the chance of the cancer returning. Because the treatment activates the immune system, it can affect healthy tissue too. Possible side effects range from skin rash and bowel problems to inflammation of organs such as the thyroid. They are monitored closely and can often be managed well. It is worth knowing that immunotherapy does not work the same for everyone, and its success cannot be predicted with certainty in the individual case. According to the American Cancer Society, these treatments have nonetheless clearly improved the outlook for advanced melanoma. Whether and how they are suitable is something the treatment team works out with you.

Alongside immunotherapy, a second modern approach has become established for advanced melanoma: targeted therapy. Rather than acting on the immune system, it works directly on specific switches inside the tumour cell that drive its growth. The condition for using it is that the tumour carries a matching change in its genetic material. In a proportion of melanomas, for example, there is a change in the so-called BRAF gene that keeps cell growth permanently switched on. Medicines that act on this switch and on a further one, called MEK, can slow the growth of such tumours. Whether targeted therapy is possible is therefore determined by testing the tumour tissue for these changes, known as mutation testing. Targeted medicines are usually taken as tablets. They often work quickly but can lose effect over time if the tumour finds ways around the blockade. They too have side effects, such as fever, joint pain or skin changes. Which sequence and combination of immunotherapy and targeted therapy makes sense in a given case is a matter for medical advice and depends on your individual situation.

Once the main treatment ends, the illness is usually not fully behind you yet. Follow-up care accompanies people for years. Its purpose is to catch a recurrence or a new skin cancer early, keep an eye on side effects and answer open questions. How closely the checks are spaced depends on the type and stage of the tumour. Anyone who has had skin cancer carries a higher risk of developing it again. That makes regular skin checks with a specialist and your own careful observation of your skin all the more important. Self-examination using the ABCDE rule and consistent sun protection become a fixed part of everyday life after treatment for many people. Beyond the physical side, the emotional side matters too. A cancer diagnosis and its treatment can be a heavy load. Many hospitals and support services offer psychological support for cancer patients. Do not hesitate to use it and to raise your questions openly at follow-up appointments.

This article offers general, carefully researched information about the treatment of skin cancer. It cannot and is not meant to replace a personal conversation with a doctor. Which treatment is right in a given case can only be judged after a thorough examination and by taking your whole situation into account. If you notice a suspicious change on your skin or feel unsure, do not wait. Have it checked by a doctor. The earlier skin cancer is found, the more gently it can often be treated.