Large Cell Neuroendocrine Carcinoma of the Lung, from the CureRays guide library.

Large cell neuroendocrine carcinoma (LCNEC) is an aggressive, fast-growing lung cancer that behaves much like small cell lung cancer; treatment combines surgery or radiation for localized tumors with chemotherapy, and increasingly immunotherapy, for advanced disease.

What it is.

Large cell neuroendocrine carcinoma sits at the aggressive end of the lung neuroendocrine family — the opposite of the slow bronchial carcinoids. It is a high-grade cancer whose cells divide rapidly and tend to spread early, so it is grouped with and often treated like small cell lung cancer, even though it can look like a non-small cell tumor on a biopsy. LCNEC is strongly associated with smoking and usually appears in older adults. Because it is uncommon and behaves unpredictably, expert pathology review and care at a center experienced with neuroendocrine tumors are important. When the cancer is caught early and confined to the lung, surgery (with chemotherapy afterward) or, for those who can't have surgery, radiation combined with chemotherapy offers the best chance of control. When it has spread, treatment centers on chemotherapy — typically the etoposide-and-platinum combination used for small cell lung cancer — now often paired with immunotherapy, while newer targeted approaches are being studied.

How radiation treats it.

Radiation damages the DNA inside cancer cells so they can no longer divide. Fast-growing cancers like LCNEC are often quite sensitive to it, which is why radiation — paired with chemotherapy — is a mainstay for localized tumors that can't be surgically removed. Modern image-guided machines shape the beam precisely to the tumor and limit dose to the healthy lung, heart, and spinal cord nearby. Treatment is painless, delivered as a series of short daily sessions, and leaves no radioactivity in your body.

The ways we can treat it.

External-beam radiation (IMRT/SBRT). Image-guided x-ray beams are shaped tightly around the tumor. For a small inoperable tumor, stereotactic body radiation (SBRT) delivers a few intense, precise sessions; for locally advanced disease, daily radiation is combined with chemotherapy.

Prophylactic cranial irradiation (selected cases). Because neuroendocrine lung cancers can spread to the brain, low-dose preventive brain radiation is sometimes considered after a good response, as it is in small cell lung cancer — though its role in LCNEC is still being defined.

Questions we hear often.

Is LCNEC the same as small cell lung cancer? Not exactly, but it behaves very similarly — it's aggressive and spreads early — so doctors often treat it with the same chemotherapy used for small cell lung cancer. Expert pathology review helps confirm the diagnosis, because LCNEC can be mistaken for other lung cancers.

Can it be cured? When LCNEC is found early and confined to the lung, surgery followed by chemotherapy offers a real chance of cure. Once it has spread, treatment focuses on controlling the disease and extending life rather than curing it, though new immunotherapy and targeted drugs are improving options.

Will I need radiation? It depends on the situation. Radiation combined with chemotherapy is standard when a localized tumor can't be removed surgically. It's also used to treat areas of spread or to ease symptoms, and preventive brain radiation is considered in selected cases.

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