Papillary cystadenoma lymphomatosum, commonly known as Warthin’s tumor, is a benign growth of the salivary glands that develops slowly and rarely causes serious health problems. This non-cancerous tumor typically appears near the ear, where the largest salivary glands are located, and affects mostly older adults, particularly those who smoke.

Epidemiology

Warthin’s tumor represents the second most common non-cancerous tumor affecting the salivary glands, accounting for approximately 2% to 15% of all tumors that develop in the parotid gland. The parotid gland is the largest salivary gland, positioned just below and in front of the ear, responsible for producing saliva to help with digestion and keeping the mouth moist.^[3][4]

This condition primarily affects older individuals, with peak occurrence happening during specific age ranges depending on gender. In women, the highest incidence occurs during their sixth decade of life, meaning between ages 50 and 60, while in men, the peak incidence shifts to the seventh decade, between ages 60 and 70.^[3]

Historically, men were more commonly affected by Warthin’s tumor than women, showing a clear male predominance. However, recent medical reports indicate that this gender difference has been declining over time. The changing pattern may reflect shifts in smoking habits across different populations, as smoking is strongly associated with this tumor’s development.^[3]

The condition occasionally occurs in younger patients, though this is less common. What makes Warthin’s tumor particularly notable is its tendency to affect both parotid glands in the same person. Between 5% and 14% of cases involve bilateral presentation, meaning tumors develop on both sides of the face, though typically at different times rather than simultaneously.^[1][4]

Causes

The exact origin and causes of Warthin’s tumor remain a subject of ongoing medical debate, despite numerous theories proposed over the years. Some researchers suggest that this benign growth arises due to certain tumor-causing effects on epithelial cells that become trapped within adjacent lymph nodes or within the parotid gland itself. Epithelial cells are the cells that form the outer layer of various tissues and organs, including the lining of glands.^[3]

Several factors have been identified as potentially contributing to the development of Warthin’s tumor. These include infection with Epstein Barr virus, a common virus that can remain dormant in the body, tobacco use, autoimmune diseases where the body’s immune system attacks its own tissues, exposure to ionizing radiation, and chronic inflammation that persists over extended periods.^[3]

Despite these identified associations, many questions remain unanswered. Medical experts continue to wonder why Warthin’s tumor predominantly affects men, and why tobacco use specifically impacts the parotid glands rather than the smaller salivary glands located inside the mouth. These puzzling aspects suggest that the complete picture of how this tumor develops has yet to be fully understood.^[3]

Risk Factors

Warthin’s tumor stands out as the only benign salivary gland tumor with a strong, well-documented association with cigarette smoking. This connection is so significant that it defines much of what we know about who develops this condition.^[3]

People who smoke cigarettes face dramatically higher odds of developing Warthin’s tumor compared to the general population. Smokers are at approximately eight times greater risk than non-smokers, making tobacco use the single most important risk factor that has been clearly identified for this condition. This strong association suggests that chemicals from tobacco smoke may directly influence the development of these tumors in the salivary glands.^[1]

Age represents another significant risk factor. The tumor rarely affects young people, instead showing a clear preference for older adults. The risk increases substantially after age 50, with most cases diagnosed in people between their 60s and 70s. This age-related pattern suggests that either prolonged exposure to risk factors or natural aging processes in the salivary glands may contribute to tumor development.^[1]

While the male predominance observed in earlier decades has been declining, historical data consistently showed men at higher risk than women. This changing pattern may reflect evolving smoking habits across genders, as more women began smoking in later generations and more men have quit smoking in recent decades.^[3]

Symptoms

Warthin’s tumor typically presents in a way that causes minimal discomfort to patients, which can sometimes lead to delayed medical attention. The tumor characteristically develops slowly over months or years, gradually increasing in size without causing pain. This painless nature distinguishes it from many other conditions affecting the salivary glands.^[1][2]

The most common and noticeable symptom is the appearance of a mass or swelling near the angle of the mandible, which is the jawbone’s corner where it turns upward toward the ear. This location corresponds to the tail of the parotid gland, the area where Warthin’s tumor most frequently develops. Patients typically notice a lump that feels soft or fluctuant when touched, meaning it may feel like it contains fluid rather than being solid.^[1][2]

The fluctuant quality occurs because of the tumor’s internal structure, which contains numerous cystic spaces filled with fluid. This characteristic texture can help distinguish Warthin’s tumor from other types of salivary gland growths during physical examination.^[2]

Because the tumor grows slowly and causes no pain, patients may live with it for many years before seeking medical attention. One documented case described a patient who had an asymptomatic tumor for eight years before pursuing treatment. The lack of urgent symptoms means that many people only consult a doctor when the mass becomes large enough to cause cosmetic concerns or when they become worried about its presence.^[2][7]

In cases where the tumor affects both parotid glands, patients may notice swelling on both sides of the face, though typically at different times. This bilateral presentation can initially cause concern, but it remains characteristic of this benign condition rather than indicating something more serious.^[1]

Prevention

Given the strong association between Warthin’s tumor and cigarette smoking, the most effective preventive measure is avoiding tobacco use entirely or quitting if you currently smoke. Since smokers face eight times the risk of non-smokers for developing this tumor, eliminating tobacco exposure significantly reduces the likelihood of tumor development.^[1]

For people who smoke, cessation programs that include counseling, behavioral support, and potentially medication can help break the addiction to tobacco. The benefits of quitting extend far beyond reducing the risk of Warthin’s tumor, as smoking cessation lowers the risk of numerous other serious health conditions including heart disease, stroke, and various cancers.^[1]

Because the tumor’s exact causes remain incompletely understood, and other risk factors like Epstein Barr virus infection or chronic inflammation are difficult to control, there are no other specific preventive strategies that have been proven effective. However, maintaining overall good health through regular medical check-ups can help with early detection if a tumor does develop.^[3]

People who notice any unusual swelling or lumps near their jaw or below their ears should seek medical evaluation rather than waiting for symptoms to worsen. Early detection, while not prevention per se, allows for timely treatment before the tumor grows larger, which can make surgical removal simpler and reduce the risk of complications.^[7]

Pathophysiology

Understanding what happens inside Warthin’s tumor at the microscopic level helps explain its characteristics and behavior. The tumor has a distinctive appearance under the microscope that pathologists can readily identify, making diagnosis more straightforward once tissue samples are examined.^[1]

The tumor’s structure includes numerous cystic spaces, which are hollow areas that give the tumor its fluid-filled, fluctuant quality when touched. These cystic spaces are surrounded by a very specific arrangement of cells: two uniform rows of specialized cells called oncocytes. Oncocytes are epithelial cells characterized by their abundant, grainy, pinkish cytoplasm when viewed under a microscope with standard staining techniques. The cytoplasm is the gel-like substance inside a cell that contains all the cellular components except the nucleus.^[1]

Within the cystic spaces, the epithelium exhibits what pathologists call papillary infoldings, which are finger-like projections that extend into the hollow areas. This papillary pattern, combined with the cystic architecture, gives the tumor its full medical name: papillary cystadenoma lymphomatosum.^[1]

Perhaps the most distinctive feature of Warthin’s tumor is the presence of abundant lymphoid tissue within its structure. This tissue resembles what you would find in lymph nodes, containing numerous lymphocytes, which are white blood cells that fight infection, and germinal centers where these immune cells multiply and mature. This lymph node-like stroma, or supporting framework, is unique among salivary gland tumors and helps pathologists distinguish Warthin’s tumor from other growths.^[1][3]

The tumor’s cellular composition and architecture remain stable over time, which explains why these tumors grow slowly and rarely undergo malignant transformation. Unlike some other benign tumors that have higher risks of becoming cancerous, Warthin’s tumor maintains its benign character in the vast majority of cases. When complete surgical removal is performed, the tumor rarely comes back, contrasting with some other benign salivary gland tumors that have higher recurrence rates.^[1][4]