Secretory Carcinoma (Salivary Gland), from the CureRays guide library.

Secretory carcinoma is a usually low-grade salivary-gland cancer driven by a specific gene fusion (ETV6-NTRK3), treated mainly with surgery and radiation — and, importantly, with a targeted pill that can shrink advanced disease.

What it is.

Secretory carcinoma is a type of salivary-gland cancer that was only recognized in the last decade or so. It was previously confused with another salivary cancer (acinic cell carcinoma) until researchers discovered it has its own distinctive gene fusion — most often ETV6-NTRK3, the same NTRK fusion found in some other rare cancers. It usually arises in the parotid gland (the large salivary gland in front of the ear) or in smaller glands of the mouth, and it can also occur in the breast, where it is called secretory (or mammary analogue) carcinoma. Most cases are slow-growing and low-grade with a good outlook, treated with surgery and sometimes radiation. The discovery of the NTRK fusion is important because targeted NTRK-inhibitor pills can dramatically shrink the cancer in the uncommon cases that become advanced.

How radiation treats it.

Radiation damages the DNA inside cancer cells so they can no longer divide. For secretory carcinoma, surgery is usually the main treatment, but radiation is an important partner after surgery when the tumor is large, the margins are close, a nerve is involved, or lymph nodes are affected — it treats the microscopic cells left behind and lowers the chance of the cancer returning. Intensity-modulated radiation shapes the dose around the salivary region and neck while sparing healthy glands and swallowing muscles to limit dry mouth and other side effects. Radiation is painless during delivery, given over several weeks of daily sessions, and external-beam treatment leaves no radioactivity in the body.

The ways we can treat it.

Intensity-modulated radiation (IMRT). Beams are shaped around the salivary region and neck to treat the tumor bed while sparing the other salivary glands, swallowing muscles, and jaw.

Proton therapy (selected). Protons can reduce dose to nearby structures for tumors near the skull base or when re-treating an area, lowering side effects.

Neutron / particle therapy (selected high-grade). For certain aggressive salivary cancers that resist standard radiation, specialized particle beams at expert centers can improve local control.

Questions we hear often.

How is this different from acinic cell carcinoma? For years secretory carcinoma was grouped with acinic cell carcinoma because they look similar. Researchers then found that secretory carcinoma has its own gene fusion (ETV6-NTRK3). Telling them apart matters because the fusion makes targeted NTRK-inhibitor pills an option for advanced secretory carcinoma.

Is it usually serious? Most secretory carcinomas are low-grade and slow-growing, with an excellent outlook after surgery. A minority are high-grade or 'transformed' and behave more aggressively, needing surgery, radiation, and close follow-up. Your team will base the plan on your tumor's grade and stage.

Why does testing for the NTRK fusion matter? Finding the ETV6-NTRK3 fusion confirms the diagnosis and, importantly, identifies a treatment: in the uncommon cases that spread, NTRK-inhibitor pills can shrink the cancer significantly and for a long time. That makes molecular testing a valuable step, especially for advanced disease.

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