Inverting papilloma

Inverting papilloma is also known as the shneiderian papilloma, in memory of Victor Conrod Shneider who described its histology.

The schneiderian mucosa lines the nasal cavity and the paranasal sinuses and it is embryologically unique in the sense that it is derived from the ectoderm. Also the tumors from this epithelium are very peculiar in their history, evolution and localization. They are associated to the human papiloma Virus (HPV).

The inverting papillomas are found to be growing inwardly and hence the term "Inverted" papilloma. Males are affected 3 times more often than females and the tumor appears between the second and the seventh decades of life.

Anatomically, papillomas can be classified depending on the site of its occurrence. They can either grow from the lateral nasal wall, or paranasal sinuses, or the nasal septum. Usually it presents as a single unilateral mass that can be mistaken with a nasal polyp.

This distinction has prognostic significance because malignant growth occurs in as many as 15% of cases of papilloma arising from the lateral nasal wall.

Most common symptoms

Usually, the patient manifests unilateral nasal obstruction with or without sinus infection, rhinorrhea and epistaxis (nose bleeds). Occasionally they suffer from headaches, facial pain, anosmia (loss of the sense of smell), and sometimes even nasal deformity or proptosis (eye bulging) if the lamina papyracea is breached.

Here is an interesting fact; 1 out of every 50 patients with nasal polyps presents an inverting papilloma.

Diagnosis

Normally, symptoms give you the most important clue about the disease and most (but not all) inverting papillomas can be found during a physical examination of the nasal cavity usually with an instrument called an nasofibroscope. Later on a CT scan of the nose and the paransal sinuses will provide important elements such as the extent of how the tumor has spread, localization and the degree of bone destruction. In some cases Magnetic Resonance Imaging (MRI) may be needed. Nevertheless a biopsy is necessary to make a definitive diagnosis.

Which is the best treatment?

Surgery is the primary treatment for inverted papillomas, especially the endoscopic endonasal approach (EEA) since this technique allows the surgeon to see and access the tumor, without making incisions on the face, giving the benefit to the patients of no incisions to heal (meaning, no scars) and a shorter recovery time.

Recurrence

Despite a successful surgery there is a recurrence rate of 40% to 80%, and multiple procedures may be needed to control the disease.