Neoplasia Case Studies II


CASE 4: Schwannoma of eighth nerve


History:

A 49-year-old woman has been bothered by headaches for several months. She also has difficulty hearing on the left. She blames it on the teenagers at the house next door playing loud rock music.

Image 4.1:

This is the gross appearance of a similar lesion in another patient. Describe the location and appearance. The tumor is well-circumscribed and is located in the region of the cerebellopontine angle, which is where the eighth nerve is. The tumor is tan and homogenous.

Image 4.2:

This is the low power microscopic appearance of the lesion. Describe the findings. The cells are fairly monotonous, without areas of hemorrhage or necrosis. There is no evidence for invasion.

Image 4.3:

What do you see in this high power microscopic appearance? What is the cell of origin? The cells have long, thin nuclei and abundant pale pink cytoplasm resembling the Schwann cells of nerve trunks. The cells show minimal hyperchromatism and pleomorphism.
  1. What further procedure(s) can be done to determine what her problem is?

    2. Simple physical examination will determine a not so subtle hearing loss, though audiometry could be helpful in determing the nature of the loss. In her case, there was evidence for nerve-deafness on the left. If an intracranial mass lesion is suspected, a CT or MRI scan of the head will aid diagnosis.

  2. How do you tell a benign from a malignant neoplasm?

    3. Benign tumors are characterized by their greater degree of differentiation, slower growth, circumscription, lack of metastases, etc.

  3. How can a histologically benign neoplasm still cause problems for the patient?

    4. Even benign neoplasms can cause problems based upon their location--they can produce a mass effect to occlude, obstruct, or cause pressure injury to surrounding structures.