Salivary gland cancer is rare. Worldwide, roughly 55,000 new cases are diagnosed each year, translating to an age-standardized rate of about 0.56 per 100,000 people. To put that in perspective, it accounts for a tiny fraction of all cancer diagnoses globally. The average age at diagnosis is around 55.
How It Compares to Other Cancers
With fewer than 56,000 annual cases worldwide, salivary gland cancer is far less common than major cancers like breast, lung, or colorectal cancer, each of which produces over a million new cases per year. It’s even uncommon among head and neck cancers, where cancers of the throat, tongue, and larynx are diagnosed much more frequently. If you’ve found a lump near your jaw or under your tongue and are researching this topic, the rarity of this cancer is important context, but it’s not the whole picture.
Most Salivary Gland Tumors Are Not Cancer
A critical point that statistics alone can miss: the majority of salivary gland tumors turn out to be benign. In one population-based study of 248 salivary gland tumors, about 84% were benign and only 16% were malignant. So finding a growth in a salivary gland does not mean cancer is likely.
That said, the odds shift depending on which gland is involved. The parotid glands (the large glands in front of your ears) produce the most tumors overall, but most of those are noncancerous. In the smaller glands, a tumor is more likely to be malignant. Roughly 40 to 45 percent of tumors in the submandibular glands (under the jaw) are cancerous. For the sublingual glands (under the tongue), that number jumps to 70 to 90 percent. And tumors in the minor salivary glands scattered throughout the mouth and throat are malignant 50 to 75 percent of the time. The general rule: the smaller the gland, the higher the chance a tumor found there is cancerous.
Where These Cancers Develop
When salivary gland cancer does occur, it most often starts in the parotid gland, simply because the parotid is the largest salivary gland and produces the most tumors overall. A Danish study found that about 53% of salivary gland cancers originated in the parotid gland, 12% in the submandibular gland, fewer than 2% in the sublingual gland, and roughly 33% in the minor salivary glands. That last number surprises many people. The minor salivary glands are tiny and spread throughout the lining of the mouth, sinuses, and throat, so cancers there can show up in unexpected locations.
Known Risk Factors
For most people diagnosed with salivary gland cancer, no clear cause is identified. The strongest established risk factor is previous radiation exposure to the head and neck area. People who received radiation therapy for an earlier cancer in that region face a significantly higher risk of developing salivary gland cancer later. This can occur years or even decades after the original treatment.
Beyond radiation, the risk factors are less well defined than for many other cancers. Age plays a role, with risk increasing in middle age and beyond. Some workplace exposures, including certain metals and radioactive substances, have been studied as possible contributors, but the evidence is less definitive than for radiation therapy. Unlike many head and neck cancers, salivary gland cancer has no strong link to tobacco or alcohol use.
Survival Rates by Stage
Survival statistics for salivary gland cancer are relatively favorable compared to many other cancers, largely because a noticeable lump near the jaw or in the mouth often prompts early medical attention. Based on data from people diagnosed between 2015 and 2021, the five-year relative survival rates break down as follows:
- Localized (cancer confined to the salivary gland): 96%
- Regional (spread to nearby lymph nodes or tissues): 70%
- Distant (spread to other parts of the body): 42%
- All stages combined: 78%
These numbers represent averages across all types of salivary gland cancer, and the variation between types is significant. Some forms, like acinic cell carcinoma, tend to grow slowly and have excellent outcomes. Others, like certain high-grade mucoepidermoid carcinomas or adenoid cystic carcinomas, can behave more aggressively or recur years after initial treatment. The specific tumor type matters as much as the stage when it comes to long-term outlook.
Why “Rare” Still Matters
The rarity of salivary gland cancer creates a practical challenge: many general oncologists see only a handful of cases in their careers. Treatment outcomes tend to be better at medical centers that handle head and neck cancers regularly, because surgical anatomy in this area is complex. The parotid gland, for instance, wraps around the facial nerve, and preserving nerve function during surgery requires specialized experience. If you or someone you know is facing a diagnosis, seeking out a head and neck cancer team with specific salivary gland experience can make a meaningful difference in both cancer control and quality of life afterward.