Dr. Edward H. Oldfield of the National Institute for Neurological Disorders and Stroke, Bethesda, Maryland, USA, is heading a study of endolymphatic sac tumors (ELST).
In addition to being associated with tumors of the kidneys, brain, spinal cord, adrenal glands and retinas, VHL has recently been associated with tumors of the inner ear. More specifically, the endolymphatic sac (ELS) has been found to be the site of origin for specific VHL-associated inner ear tumors. The ELS is thought to be a site of regulation of inner ear fluids. Tumors of this sac (ELST) have been associated with hearing loss (either sudden or gradual) as well as vertigo (balance disorder) and tinnitus (noise in the ear). In the limited cases that have been described in the literature, the recommendation has been for immediate surgical removal of the tumor. However, the rarity of this tumor has resulted in most tumors only being recognized after they have grown quite large and already caused deafness and balance dysfunction.
At NIH, one of the largest groups of VHL patients has been studied and followed on a regular basis. This has provided the unique opportunity to closely examine patients with this disease and detect these inner ear tumors very early in their development. The advantage is that ELST’s can be removed before they can cause permanent hearing loss and vertigo. Since there have been no reports on early intervention for early stage ELST’s, the basis for recommending this surgery for early tumors is preliminary data from the NIH experience. Of the 13 patients with late stage ELST’s diagnosed at the NIH, all 13 have shown severe deafness and balance dysfunction. A review of the case reports in the literature seem to support this observation. Therefore it seems that untreated ELST’s will eventually cause hearing loss and/or balance dysfunction. The exact timeframe for development of these problems is not known.
Candidates for this study will have confirmed or suspected ELST based on audiologic or vestibular testing. Candidates may choose surgery, or non-surgical follow-up at 6-12 month intervals for five years, with neurologic, audologic testing, and MRI scanning of the inner ear region. If necessary, you and your doctors could elect to change your management to one involving surgery. The goals of the study are to find better ways of diagnosing ELSTs early, and finding optimal treatments that preserve hearing and balance.
Eligible patients who have already been seen at NIH will be invited to participate. If you believe that you may also be a candidate for this study, you are welcome to contact Suzanne Lischynsky, R.N., of the office of Dr. Edward H. Oldfield, 301-496-5728, Fax: 301-402-0380.
People will be excluded from the study if they are: pregnant or lactating; have multiple abnormalities of the middle and inner ear that would complicate analysis of the cause of hearing loss; patients undergoing chemotherapy with ototoxic agents. Additional inclusion and exclusion criteria are available from Ms. Lischynsky.
The U.S. National Institutes of Health (NIH) is performing research to understand the genetic abnormalities that lead to the development of tumors in people with VHL. This work has led to the identification of the VHL gene, as well as an understanding of which types of mutations lead to the growth of different tumors in people with VHL. Ongoing natural history studies are describing the growth of different tumors over time, the correlation with VHL gene mutation type, and the effect of smoking on tumor growth.
The NIH has continued interest in evaluating the natural history of tumors found in people with VHL, genetic abnormalities associated with these tumors, and the role of environmental exposure to the growth of these tumors. Medical care and travel expenses are provided by the U.S. Government.
Interested people with VHL should call +1 (301) 496-6353.
The clinical trial of an angiogenesis inhibitor starting in Boston this year is still looking for subjects. Details are in the December 1998 issue of VHLFF, or at www.vhl.org. For more information, please contact Sarah Mott at the office of Dr. William Kaelin, 617-632-4747, Fax 617-632-4381, or e-mail: sarah_mott@dfci.harvard.edu
As printed in the VHL Family Forum 7:1, March 1999. For permission to reprint, please contact VHL Family Alliance, info@vhl.org.
