49 yo chinese man comes to GP with sinus pain and difficulty breathing through nose. Has prior episodes of epistaxis. No tabacco history. Came to use 12 years ago works as cook. Vitals are normal. Physical exam shows ulcerated lesion in left nostril and slight asymmetry of posterior pharynx and normal intact tonsils. CT of head shows mass involving nose, pharynx and maxillary sinus. Biopsy shows nonkeratinizing squamous cell carcinoma. 1. What is your diagnoisis? 2. What viral infection is associated with this condition? 3. What other malignancy is associated with this viral infection?

The main function of the respiratory system is gas exchange (O2 and CO2). Ventilation is the movement of air through the respiratory tract into (inspiration) and out of (expiration) the respiratory zone (lungs).