Warthin's tumor overview

# Overview
Warthin's tumor is a type of benign tumor of the salivary glands.  It is also known as benign papillary cystadenoma lymphomatosum.  Its etiology is unknown, but there is a strong association with the cigarette smoking.  Smokers are at 8 times greater risk of developing Warthin's tumor than the general population. Warthin's tumor arises from salivary gland epithelium, which are secretory cells of the salivary gland. On gross pathology, cystic and multicentric appearance are characteristic findings of Warthin's tumor. On microscopic histopathological analysis, papillae, fibrous capsule, and cystic spaces are characteristic findings of Warthin's tumor. Warthin's tumor must be differentiated from salivary gland cysts, salivary gland lymphoma, and salivary gland cancer. The prevalence of Warthin's tumor is estimated to be 2000 to 2500 cases annually. Warthin's tumor commonly affects elderly patients greater than 60 years old. Males are more commonly affected with Warthin's tumor than females. The male to female ratio ranges from 2.6:1 to 10:1. The most potent risk factor in the development of Warthin's tumor is smoking. Other risk factors include irradiation, Epstein-Barr virus, and alcohol. If left untreated, few patients with Warthin's tumor may progress to develop facial paralysis. Common complications of Warthin's tumor include squamous cell carcinoma and facial paralysis. Prognosis is generally good. The most common symptoms of Warthin's tumor include swollen salivary gland, lump near the back of the lower jaw, jaw pain, the sensation of pressure, facial nerve paralysis, tinnitus, impaired hearing, earache, etc. X-ray, computed tomography (CT) scan and magnetic resonance imaging (MRI) may help diagnosis. Surgery is the mainstay of treatment for Warthin's tumor. As a benign tumor, the prognosis of Warthin's tumor is good.

# Historical Perspective
Warthin's tumor was first discovered by Hildebrand, a German surgeon, in 1895.

# Pathophysiology
Warthin's tumor arises from salivary gland epithelium, which are secretory cells of the salivary gland. On gross pathology, cystic and multicentric appearance are characteristic findings of Warthin's tumor. On microscopic histopathological analysis, papillae, fibrous capsule, and cystic spaces are characteristic findings of Warthin's tumor.

# Causes
There are no known direct causes for Warthin's tumor.

# Differential Diagnosis
Warthin's tumor must be differentiated from salivary gland cysts, salivary gland lymphoma, and salivary gland cancer.

# Epidemiology and Demographics
The prevalence of Warthin's tumor is estimated to be 2000 to 2500 cases annually. Warthin's tumor commonly affects elderly patients greater than 60 years old. The male is more commonly affected with Warthin's tumor than female. The male to female ratio ranges from 2.6:1 to 10:1.

# Risk Factors
The most potent risk factor in the development of Warthin's tumor is smoking. Other risk factors include irradiation, Epstein-Barr virus, and alcohol.

# Natural history, Complications and Prognosis
If left untreated, few patients with Warthin's tumor may progress to develop facial paralysis. Common complications of Warthin's tumor include squamous cell carcinoma and facial paralysis. Prognosis is generally good.

# History and Symptoms
The hallmark of Warthin's tumor is swelling of jaw, cheek, mouth, or neck. A positive history of swollen salivary gland and jaw pain is suggestive of Warthin's tumor. The most common
symptoms of Warthin's tumor include tinnitus, an earache, and blood in saliva.

# Physical Examination
Patients with Warthin's tumor usually appear well. Physical examination of patients with Warthin's tumor is usually  remarkable for mobile nontender mass which is firm, solitary, and normal in color and appearance.

# Laboratory Findings
There are no diagnostic lab findings associated with Warthin's tumor.

# CT
Neck CT scan may be helpful in the diagnosis of Warthin's tumor. Findings on CT scan suggestive of Warthin's tumor include cystic lesion posteriorly within the parotid with a focal tumor nodule and absence of calcifications.

# MRI
On MRI, Warthin's tumor is characterized by well-defined bilateral lesions which are heterogeneous and variable in signal intensity.

# Echocardiography or Ultrasound
Neck ultrasound may be helpful in the diagnosis of Warthin's tumor. Findings on neck ultrasound suggestive of Warthin's tumor include  well defined, ovoid, hyperechoic mass with internal cystic areas and hypervascularity.

# Other Imaging Findings
Other diagnostic studies for Warthin's tumor include scintigraphy, which demonstrates uptake of with Tc99-pertechnetate, thallium, and FDG-PET.

# Biopsy
On biopsy, Warthin's tumor is characterized by cystic spaces surrounded by two uniform rows of cells with centrally placed pyknotic nuclei, papillae with a two rows of pink epithelial cells, and lymphoid stroma.

# Surgery
Surgery is the mainstay of treatment for Warthin's tumor.

# Reference