Nasopharyngeal cancer invading into pterygoid sinus belongs to stage III or IV clinically. Nasopharyngeal cancer is a kind of malignant tumor disease of head and neck, which is caused by abnormal proliferation and differentiation of nasopharyngeal cells, and patients need to implement appropriate treatment plans according to the clinicopathological stage. According to AJCC TNM staging of nasopharyngeal cancer, when the primary tumor invades the skull base, cervical vertebrae, pterygoid structure and/or paranasal sinus, it belongs to T3, and the pterygoid sinus belongs to paranasal sinus, therefore, once nasopharyngeal cancer invades the pterygoid sinus, it means that the patient is in stage III and above of nasopharyngeal cancer, and the specific staging also needs to depend on the metastasis of the regional lymph nodes and whether the metastasis is in the distant place or not. If you find abnormal symptoms in nasopharynx, you should consult doctor in time to avoid delaying treatment.