Classification The World Health Organization (WHO) has identified three subtypes of<unk> : * type 1: squamous cell<unk> , typically found in older adults * type 2: non-keratinizing<unk>  * type 3: undifferentiated<unk>  Type 3 is most commonly found among younger children and adolescents, with a few type 2 cases. Both type 2 and 3 have been found to be associated with elevated levels of Epstein-Barr virus titers, but not type 1. Additionally, type 2 and type 3 may be followed with an influx of inflammatory cells, including lymphocytes, plasma cells, and eosinophils, generating the term lymphoepithelioma.<unk> , also known as nasopharyngeal cancer, is classified as a malignant neoplasm, or cancer, arising from the mucosal epithelium of the nasopharynx, most often within the lateral nasopharyngeal recess or fossa of Rosenmüller (a recess behind the entrance of the eustachian tube opening). The World Health Organization classifies<unk>  in three types, in order of frequency: Non-keratinizing squamous cell<unk> ; keratinizing squamous cell<unk> ; and basaloid squamous cell<unk> . The tumor must show evidence of squamous differentiation, with the non-keratinizing type (also known as lymphoepithelioma) the tumor most strongly associated with Epstein-Barr virus infection of the cancerous cells. Image:Lymphoepithelioma met to LN 4.Undifferentiated<unk> —low power Image:Lymphoepithelioma met to LN 1.Undifferentiated<unk> —med. power Image:Lymphoepithelioma met to LN 2.Undifferentiated<unk> —high power Image:Lymphoepithelioma met to LN 6.Undifferentiated<unk> —high power Staging FDG-PET/CT scan of a patient with nasopharyngeal cancer. Transverse slice demonstrating FDG-positive primary site Staging of<unk>  is based on clinical and radiologic examination. Most patients present with Stage III or IV disease. Stage I is a small tumor confined to nasopharynx. Stage II is a tumor extending in the local area, or that with any evidence of limited neck (nodal) disease. Stage III is a large tumor with or without neck disease, or a tumor with bilateral neck disease. Stage IV is a large tumor involving intracranial or infratemporal regions, an extensive neck disease, and/or any distant metastasis. File:Diagram showing stage T1 nasopharyngeal cancer CRUK 249.Stage T1 nasopharyngeal cancer File:Diagram showing stage T2 nasopharyngeal cancer CRUK 257.Stage T2 nasopharyngeal cancer File:Diagram showing stage T3 nasopharyngeal cancer CRUK 264.Stage T3 nasopharyngeal cancer File:Diagram showing stage T4 nasopharyngeal cancer CRUK 270.Stage T4 nasopharyngeal cancer
Nasopharyngeal carcinoma
Laryngeal cancer
Oropharyngeal cancer
Hypopharyngeal cancer
Adenoiditis
Laryngeal papillomatosis
Nasopharyngeal cyst
Laryngeal cyst