Rare malignant tumor in the ear, which took place in the ear by 85%, 10% of external ear, middle ear 5%. In the early ear cancer, the most common predilection sites for the helix, accounting for 50%, followed by the central part of the auricle (including ear A, scaphoid fossa of the helix, etc.) accounted for 30%, occurred in the posterior auricular accounted for 12%, occurred in other parts account for only 8%.
Ear tumor in the incidence between males and females are similar base, but the incidence of the external auditory canal cancer more women than men. In addition to embryonal rhabdomyosarcoma more common in children, the ear cancer generally occurs in the elderly. With disease site, ear cancer, the average age of onset was 70 years old, 55-year-old canal cancer, middle ear and mastoid carcinoma was 56 years old. According to histological type, squamous cell carcinoma average age was 64 years old, basal cell carcinoma was 69 years, salivary gland 47 years.
Cause of ear canal tumors and other tumors, as the current is still not very clear, the external auditory canal tumor virulence factors may be with the following factors:
1 canal cancer risk factors. Otitis externa and otitis media in the external ear and middle ear cancer most associated with long-term recurrent ear purulent discharge.
External auditory canal tumor risk factors 2. External stimuli sun, dust or chemical substances can induce long-term stimulation of auricular malignant tumors, such as the incidence of malignant melanoma and sun exposure may be related.
3. Papilloma virus infection of the external auditory canal and the occurrence of subtypes of HPV 6 (HPV6) relevant, easy to malignant disease, whether malignant transformation of HPV infection caused by the is not yet sure. The EDV in the pathogenesis of lymphoma, the role, now more positive. Known occurrence of Kaposi's sarcoma and HIV infection are closely related.
External auditory canal tumor risk factors 4. Carcinogenic substances stimulate aflatoxin found in the external auditory canal R have significant carcinogenic suspicious. The role of other carcinogens can not be ignored.
5. Radiation induced occupational ties or head and neck cancer radiotherapy, many years later the ear can be induced malignant tumors, such as nasopharyngeal cancer after radiotherapy can induce middle ear or malignant histiocytoma.
6. Immune suppression or absence of immunosuppressants after organ transplantation therapy, can induce the body parts of the tumor. AIDS, acquired immune deficiency syndrome, also known, can occur in the dominant period of Kaposi's sarcoma or network system tumors.
External auditory canal tumor risk factors 7. Oncogenes or tumor suppressor gene in vivo cancer gene mutations lead to cancer, the present study more.
- external ear canal tumor