Basal Cell Carcinoma (Skin Cancer), from the CureRays guide library.

Basal cell carcinoma is the most common cancer in people — a slow-growing skin cancer that almost never spreads, is highly curable, and can often be treated without surgery using precise radiation that preserves the look and function of the skin.

What it is.

Basal cell carcinoma (BCC) is a cancer that begins in the basal cells, the deepest layer of the outer skin (the epidermis), where new skin cells are made. It is the most common cancer of any kind in the world, and it is caused mostly by years of ultraviolet (UV) light from the sun or tanning beds. BCC usually appears on areas that get the most sun — the face, nose, ears, scalp, neck, and the backs of the hands — often as a pearly or waxy bump, a flat scaly patch, a sore that won't heal, or a spot that bleeds and scabs over and over. The good news is that basal cell carcinoma grows slowly and almost never spreads to other parts of the body, which makes it one of the most curable of all cancers. The main concern is local: if it is ignored, it can keep growing into the skin and the structures underneath, and on the face it can affect sensitive areas like the eyelid, nose, and ear, where removing it surgically may be difficult or leave a noticeable change in appearance. That is exactly where radiation therapy becomes valuable — it can cure these cancers without cutting, preserving the natural shape and function of delicate areas. Because BCC reflects a lifetime of sun exposure, many people who get one will develop others over time, so regular skin checks and sun protection are an important part of care.

How radiation treats it.

Radiation therapy treats basal cell carcinoma by delivering focused beams of energy that damage the DNA inside the cancer cells, so they can no longer grow and divide and eventually die off, while the surrounding healthy skin recovers. For skin cancer this is especially elegant, because the tumor sits at or just below the surface, and the radiation can be tuned to treat exactly that depth and go no deeper. Superficial radiation therapy uses low-energy X-rays, and electron-beam therapy uses electrons that stop at a chosen shallow depth — both concentrate the dose on the cancer while protecting the tissue underneath, such as cartilage, bone, the eye, or the brain. This makes radiation a powerful option for cancers on the nose, eyelids, ears, and lips, where surgery can be technically difficult or can change a person's appearance, and for older patients or anyone who cannot have or prefers to avoid an operation. Treatment is painless and is usually given as a series of short sessions over several weeks; spreading the dose out lets healthy skin heal between visits and gives a better cosmetic result. Modern approaches can add high-frequency ultrasound to see the tumor's exact depth and edges, so the beam is aimed accurately and the response can be tracked. Cure rates with radiation for appropriately selected basal cell cancers are very high — comparable to surgery — and because the surrounding structures are spared, the natural shape and function of delicate areas are preserved. Radiation can also be used after surgery when a tumor has aggressive features or its edges could not be fully cleared, lowering the chance it comes back.

The ways we can treat it.

Superficial radiation therapy (SRT). Low-energy X-rays treat the cancer right at the skin surface and a short distance below it, delivering the dose to the tumor while sparing deeper tissue — a non-surgical cure ideal for delicate facial areas.

Electron-beam radiation. Electrons deposit their energy at a controllable, shallow depth and then stop, making them well suited to skin cancers because they treat the tumor without dosing structures underneath.

Image-guided SRT (SRT with ultrasound). High-frequency ultrasound shows the depth and borders of the tumor so the radiation can be aimed precisely and tracked over the course of treatment, improving accuracy and confirming response.

Brachytherapy (surface molds) in selected cases. A custom applicator placed against the skin delivers radiation from very close range, useful for curved or irregular surfaces like the nose or ear where shaping the dose to the contour matters.

Questions we hear often.

Is basal cell carcinoma dangerous? Basal cell carcinoma is rarely life-threatening because it almost never spreads to other parts of the body. The concern is local: if left untreated it can keep growing and damage nearby tissue, which matters most on the face near the eye, nose, and ear. Treated promptly, it is one of the most curable of all cancers.

Can it be cured without surgery? Yes. Radiation therapy cures basal cell carcinoma without any cutting, with success rates comparable to surgery for appropriately selected tumors. It is especially valuable on the nose, eyelids, ears, and lips, where surgery can be difficult or change appearance, and for people who cannot have or prefer to avoid an operation.

If I've had one basal cell carcinoma, will I get more? It's common. Because BCC reflects a lifetime of sun exposure, many people who develop one go on to develop others. That makes ongoing skin checks and sun protection — sunscreen, hats, and shade — an important part of keeping cancer away after treatment.

This guide is informational only. It is not medical advice — please confirm anything here with your care team.