الفهرس 
Anatomy of the nasopharynxOnly 14 pages are availabe for public view
Abstract
Nasopharyngeal cancer is the 20th most common cancer in the world. Nasopharyngeal carcinoma (NPC) represents the majority of it. NPC shows a distinct racial and geographical distribution and it had many interacting risk factors especially Epstein-Barr virus (EBV).
The aim of this work was hospital based registration of different types of malignant tumors of nasopharynx in Ain shams University Hospital and Ain Shams Specialized Hospital during the period of 7 years (2111-2117), in order to confirm the histological diagnosis and to detect the relative frequency in relation to the total malignant tumors.
Revision of H&E stained slides and Immunohisto-chemical staining of cases with unproved diagnosed to verify it by both CK and LCA were done, also the available clinical data regarding age, sex, and presentation was collected from files of Ain Shams Hospitals during the period from 2111-2117. The study included 20 cases; all of them were primary cases.
The results of the study showed that the malignant tumors of the nasopharynx represent approximately 1.00 of all malignant tumors.
Concerning the age of the patients, it ranged from 13 to 83 years. The mean age was 00.0 years with no specific age group predilection. The cases includes 17 male patients (02.70) and . female patients (35.70), with male to female ratio 1.5.1.
The most common clinical presentations were nasal obstruction and neck mass followed by otological symptoms. The mean of the duration passed between onset of symptoms and pathological diagnosis was 5 month and it ranged from 2 to
20 months.
Histopathological examination aided by immunohisto-chimical staining revealed that nasopharyngeal carcinoma was the commonest malignant tumor representing 70.20 of cases (by immunostaining, they were CK positive and LCA negative) followed by non Hodgkin lymphoma representing 01.50 (by immunostaining, they were CK negative and LCA positive). Soft tissue tumors were represented by only one case of malignant prephral nerve sheath tumor (0.20) (by immunostaining, it was both CK and LCA negative and it was focally positive for S111).
Concerning nasopharyngeal carcinoma cases; all of them were nonkeratinised undifferentiated with exception of only one case (5.50) showing features of differentiation. The mean age of cases was 0..1 years and it was more in males with male to female ratio 2.27:1.
Concerning non Hodgkin lymphoma cases; all except one was of diffuse large B cell type and the mean age of the cases was 01.7 years with equal sex distribution.