Hearing Changes and VHL

If you or anyone in your VHL family experiences hearing loss, hearing changes, persistent ringing in the ears (tinnitus), vertigo (dizziness) or otalgia (earache), it is a good idea to go for a thorough audiology examination to determine the extent of any hearing loss. In addition, an MRI of the internal auditory canal can be used to look for an endolymphatic sac tumor (ELST).

This VHL tumor is thought to be rare, but may be more prevalent, because it is difficult to diagnose and generally does not cause severe problems. It tends to be a very slow-growing tumor, with symptoms reported for as long as thirty years before diagnosis, but which may take only a few years to develop. People report hearing changes which range from subtle changes in the "texture" of the hearing to profound hearing loss. It is a condition which is sometimes misdiagnosed as Menière’s disease. It is only in the last three years that it has been understood that there can be hearing changes associated with VHL. This discovery was due in part to pooling of medical information through the VHLFA.

The endolymphatic sac is a very small structure, about 4 x 4 mm, that plays a major role in inner ear homeostasis (endolymph production and resorption) and inner ear immune defense. We know that its injury causes hearing loss, and we know too that probably the endolymphatic sac is the main cause of Meniere’s disease.

The tumor is not often seen. In Dr. Richard’s study, there were only 59 documented cases of ELST in the literature, two-thirds of which were women, and 13 of which were associated with VHL. In the French registry which he maintains he has found another 15 unpublished cases. Compare this with 495 VHL patients with hemangioblastoma of the cerebellum and spinal cord.

Dr. Richard describes ELST as a locally aggressive papillary tumor of the temporal bone which has not been found to spread to other parts of the body. The tumor may remain in the internal auditory canal, or it may attach to the petrous bone. Sometimes the hearing change comes first before the tumor is seen, and other times the tumor can be clearly seen before there is any change in the hearing.

Dr. Oldfield at the National Institutes of Health sees patients selected after extensive audiometric testing done under the NIH Screening program headed by Dr. Linehan. hoping to learn the indicators to diagnose ELST earlier, but for now they use a combination of MRI and CT scans of the internal auditory canal. Dr. Heffner from the Armed Forces Institute of Pathology added his collection of ELST tumors to the study.

Please report confirmed endolymphatic sac tumors (ELST) to the VHL Family Alliance Research Database to help increase our knowledge. At this time, there is no known routine treatment for these tumors which will preserve hearing, they are often best left in place. Neurosurgeons, neuro-otologists, or Ear Nose & Throat (ENT) specialists who are informed about ELST may evaluate and make recommendations. Contact the VHL Family Alliance at 1-800-767-4VHL or info@vhl.org for referral to the latest information about VHL and hearing issues.

Our thanks to Dr. Edward Oldfield, National Institute for Neurological Disorders and Stroke, Bethesda, Maryland; Dr. Stéphane Richard, Necker Hospital, Paris, France; and Dr. Gladys M. Glenn, National Cancer Institute for their kind assistance in the preparation of this article.

As published in the VHL Family Forum, 4:3, September 1996. For permission to reprint, please contact the VHL Family Alliance, editor@vhl.org. Further information is available from the VHL Family Alliance, info@vhl.org.