Nasal cancer refers to malignant tumors that originate in the nasal cavity, mostly in the lateral wall of the nasal cavity, such as the middle turbinate, middle nasal passage and inferior turbinate. However, septal cancer is more likely to have cervical lymph node metastasis than lateral nasal wall cancer. Undifferentiated carcinoma and squamous cell carcinoma are the most common types of nasal cavity cancer. Other types of carcinoma include adenoid cystic carcinoma, adenocarcinoma, basal cell carcinoma, olfactory neuroepithelial carcinoma and lymphoepithelial carcinoma. Secondary nasal cancers mostly originate from the sinuses, such as maxillary sinus cancer and septal sinus cancer, which often invade the nasal cavity. Occasionally, malignant tumors from distant organs may metastasize to the nasal cavity, including adrenal cancer, kidney cancer, laryngeal cancer, lung cancer, breast cancer, gastric cancer, liver cancer, etc., but they are rare. The biological behavior of secondary nasal cancer varies greatly depending on its primary site. The symptoms of nasal malignancy show progressive aggravation and are mostly asymptomatic in the early stage, while nasal congestion and bloody mucus may be present in the late stage. However, early signs of nasal cancer can be detected if observed carefully. What are the early signs of nasal cancer? I. Long-term persistent one-sided nasal congestion with progressive aggravation and nasal flow with large amount of foul-smelling nasal mucus. II. Recent frequent blood in the nose or nasal bleeding, frequent bleeding from nasal polyps, facial headache and numbness, or painful or loose teeth grinding, sometimes pus in the teeth. Third, from intermittent headache to persistent aggravation, after the original nasal disease appears trigeminal neuralgia, unexplained facial muscle spasm. IV. Recent sudden loss of smell, foreign body sensation in breathing, persistent eyelid spasm, or tearfulness, or ectopic eyes. V. Sudden unilateral hearing and vision loss. Routine diagnosis Nasal cancer is more common in males. Nasal bleeding, nasal congestion and nasal swelling are the three major symptoms of nasal cancer. In the early stage, there are often only unilateral nasal congestion and nasal bleeding, and nasal bleeding often occurs frequently and the bleeding volume is not much, which may only be manifested as nasal discharge with blood, which is easy to be ignored or misdiagnosed. With the development of the lesion, numbness and fullness of the face and nose, intractable headache, progressive and persistent unilateral nasal congestion, bleeding mucus and olfactory disturbance may appear, and sometimes patients may complain of finding nasal masses or changes in the shape of the nose. With the development of lesion, it may be accompanied by infection, tumor ulceration, foul-smelling bloody pus, and repeated heavy nasal bleeding. In long history, the tumor may block the nasal cavity, push the nasal septum to the opposite side, or break through the septum to involve the opposite nasal cavity. In advanced stage, the tumor may expand widely in the nasal cavity, often invading the sinuses, nasopharynx, orbit, palate, alveolus and other parts of the nose and showing corresponding clinical symptoms, such as vision loss, diplopia, eye displacement, proptosis, cheek bulge, palatal mass, tinnitus, hearing loss and severe headache. Eventually, patients may develop anemia, cachexia, cervical lymph node metastasis or distant metastasis. Physical examination shows that the tumor is generally exostotic cauliflower-like papillae or mulberry-like masses with bleeding and ulceration, pink to red in color, hard and brittle in texture, prone to infection and necrosis, often accompanied by polyps or purulent sinusitis. Most of the patients are already in advanced stage when they visit the clinic, and the tumor has already extended beyond the nasal cavity to the adjacent organs, so it is difficult to determine its primary site. Early diagnosis depends on the attention and vigilance of early symptoms and timely biopsy. For those over 40 years old who have recently developed unilateral progressive nasal congestion with bloody nasal discharge, or those with long-term sinusitis and recent severe headache and nasal bleeding, and those who recur rapidly after repeated removal of polyps, the possibility of nasal cancer should be suspected and should be repeatedly investigated in detail. CT scan of sinus can help to clarify the primary site of tumor and its extended invasion range, and should be listed as routine examination. CT scan of sinus can show tumor invasion of bone more clearly, but sometimes it is not easy to distinguish from obstructive inflammation of sinus, so intensive CT examination should be performed at this time. If the tumor involves cavernous sinus, infratemporal fossa, saddle area or invades important structures such as frontal lobe, MRI examination can obtain details of the extent of soft tissue destruction by the tumor in the above areas. For the diagnosis of nasal cavity cancer, it depends on biopsy, but sometimes there is a layer of necrotic tissue on the surface of nasal cavity cancer, if the biopsy is superficial, the tumor may not be retrieved, but if a large piece of tissue is biopsied in depth, it may cause a large amount of bleeding, therefore, when biopsy is performed, the surface necrotic tissue is removed first, and then the outer layer of the tumor entity is retrieved, and the piece of tissue should be sufficient. CT scan of sinus can help to clarify the primary site of tumor and its extended invasion range. Nasal cavity cancer can be clinically divided into four stages Stage I: tumor is confined to the nasal cavity without metastasis or extension manifestation. Stage II: The tumor destroys the bone wall of nasal cavity, invades into one of the adjacent sinuses or extends into the contralateral nasal cavity, but there is no definite cervical lymph node metastasis or stage I tumor is accompanied by movable suspicious lymph node metastasis. Stage III: The tumor has obviously invaded into the sinus or orbit, without or with movable cervical lymph node metastasis or stage I and II tumors with fixed cervical lymph node metastasis. Stage IV: The tumor invades the skull base with or without metastasis, or any stage of tumor with distant metastasis.