Sebaceous cyst: This is the most common type of cyst found in the ear canal, often resulting from a blocked sebaceous gland. It presents as a small, painless, and usually solitary nodule.

Epidermoid cyst: Also known as keratin cysts, these are benign growths that can occur in the ear canal, often due to the accumulation of keratin from skin cells. They can be similar in appearance to sebaceous cysts but may grow larger.
Acoustic neuroma: Although not a cyst in the traditional sense, an acoustic neuroma is a benign tumor that can present as a mass in the ear canal, affecting hearing and balance. It originates from the nerve that runs from the inner ear to the brain.
Middle ear cyst (e.g., cholesterol granuloma): These cysts occur in the middle ear and can be associated with a history of chronic otitis media or Eustachian tube dysfunction. They may cause hearing loss, ear fullness, or discomfort.

Malignant tumor (e.g., squamous cell carcinoma): Although rare, any mass in the ear canal could potentially be a sign of cancer. Early detection is crucial for effective treatment, making it essential not to miss this diagnosis.
Cerebellopontine angle (CPA) tumor: Tumors in this area, including acoustic neuromas, can present with symptoms similar to those of an ear canal cyst, such as hearing loss or tinnitus. Missing this diagnosis could lead to significant morbidity.

Dermoid cyst: A congenital anomaly that can occur in the ear canal, containing skin and sometimes hair, due to abnormal embryonic development.
Branchial cleft cyst: Typically found in the neck, these congenital anomalies can rarely present in the ear canal, especially if they are related to the first branchial cleft.
Glandular cysts (e.g., ceruminous gland adenoma): These are rare, benign tumors of the ceruminous glands in the ear canal, which can mimic sebaceous or epidermoid cysts in appearance.