Diagnosis and treatment of nasal invagination papilloma

  Nasal inverted papilloma (NIP) is one of the most common benign neoplasms in rhinology. It is characterized by a high degree of epithelial hyperplasia and a tubular or finger-like penetration of the epithelial mass into the subcutaneous mesenchyme, resulting in a characteristic morphological appearance. The appearance is generally papillary or myxoid as shown in Figure 1, and sometimes the tumor has polyp-like changes, so it is often misdiagnosed as nasal polyp.  Symptoms: It may manifest as nasal congestion, pus, or blood in the nose. The onset is mostly unilateral.  Onset characteristics: Individuals with the first onset of the disease often have a local origin of the tumor, and this is the center of origin, which can be located in the nasal cavity or in the sinuses, and the order of the most frequent sinuses is generally: septal sinus 〉 maxillary sinus 〉 pterygoid sinus 〉 frontal sinus. The tumor’s trophoblastic vessels are often present in this germinal center, which often cause more obvious bleeding when the tumor is removed to the root tip during surgery. At the same time, due to the influence of tumor tissue invasion on the adjacent bone, the adjacent bone at the origin of this tumor often shows gross, blurred or thickened phenomena (e.g. Figure 2). This provided the basis for our preoperative diagnosis of the disease by imaging data (mainly sinus CT). In contrast, this imaging feature is atypical in recurrent cases because of the multicentric origin or even extensive involvement. In addition, the disease may show a distinct “cerebral gyrus sign” on enhanced MRI.  Treatment: Once the tumor is diagnosed, it should be treated surgically as soon as possible. The most ideal procedure is nasal endoscopic resection of the tumor. Of course, if local hospitals are not equipped with nasal endoscopic surgery, open surgery with lateral nasal incision is also possible as long as complete resection is possible. The first chance of surgery should be especially cherished because it is probably the highest chance of complete removal of the tumor. If the site of origin of the tumor can be clearly identified during the surgery, and the tumor can be adequately excised locally (sometimes by grinding away the lesioned bone), then it will be possible to “finish the job in one go”. Generally speaking, the more recurrent the case is, the more difficult the surgery will be. This is because the site of tumor is no longer typical and may be diffuse, and the scar formed during the previous surgery may affect the identification and removal of the tumor during surgery.  Prognosis: The disease has a certain tendency of malignant transformation, therefore, doctors should cherish every surgical opportunity. Therefore, doctors should cherish every opportunity to operate and try to “end” the tumor in their own hands before it becomes malignant.  Other: Endoscopic surgical techniques are the best choice for the treatment of involuted papilloma because of the minimal trauma and quick recovery. At the current technical level, the most difficult is the tumor of the primary frontal sinus, which requires skilled endoscopic skills at large angles (70°) and the necessary adjuvant incisions (e.g., brow arch incision) to complete the procedure. The greatest risk is for tumors of the primary pterygoid sinus, especially in cases with osseous destruction of the lateral wall of the pterygoid sinus. This is because of the possibility of fatal hemorrhage caused by intraoperative injury to the internal carotid artery.