Updating the Screening Protocol

The screening protocol in the VHL Handbook has been working well throughout the world. It has been evaluated in studies in the US, UK and Denmark, and has been found to be very helpful in identifying issues early enough to be helpful in influencing treatment decisions.

The only issue we have had with it since the beginning is that it calls for a great deal of imaging, which is expensive and requires a lot of time on the part of the patient each year. In light of the concerns raised in the press in the last year about radiation dosages in imaging, we convened an international working group (12 people from six countries) prior to the Rio meeting to see what adjustments we might want to make in the 2011 version of the Handbook, especially in the Screening Protocol.

As ever, the Handbook is intended to be used by a patient and their local doctor, to help both get up to speed on the recommendations of the experts on VHL. It is not intended to replace your local medical team, but to supplement what they know, add information about what is different about VHL that they might not be familiar with, and provide leads to key journal articles and sources of second opinions. In the case of the screening protocol, it outlines what we have learned about how best to manage the health of someone with a diagnosis of VHL, but who has not yet experienced symptoms in a particular area of the body. Once there are symptoms, the local team will be assumed to know best and can contact one of the experts listed if they would like assistance. But in the absence of symptoms, the relevant section of the screening protocol should apply.

We decided that CT’s should be avoided for all pre-symptomatic people. That allowed us to simplify the categories to only three: ages zero to four; ages 5–15; and ages 16+. Once a tumor has been identified, CT still has an important role to play.

In testing for pheochromocytoma or paraganglioma, the new handbook should state that the Plasma Free Metanephrines (PFM) blood test is the preferred test. Because it is not always available, 24-hour urine is still good, but PFM is better. It should also be noted that MIBG only finds about 85% of pheos, whereas F-DOPA PET finds 98%. Again, F-DOPA PET has only limited availability, so MIBG will still be used.

In the 16+ age category, the recommendation is to schedule an MRI of the abdomen every two years, alternating with a Quality Ultrasound. We define Quality as having a good quality ultrasound machine and an operator experienced in sonography of the kidneys, adrenals, and pancreas. Ultrasound results are highly dependent upon the quality and experience of the operator. While ultrasound is less expensive, it can also miss a large number of tumors. It was felt that it is better to avoid the radiation of a CT, and having the MRI every two years should catch anything missed on the US in time to make
a difference in treatment.

Also in the 16+ category, for monitoring of the central nervous system, the group recommendation is every two years to perform “MRI with contrast of brain and cervical spine, with thin cuts through the posterior fossa, and attention to inner ear/petrous temporal bone to rule out both ELST and hemangioblastomas of neuroaxis.” The thinking is that these are the areas where early diagnosis is critical, and symptoms are sometimes slow to develop, so that imaging is particularly important in finding issues before they become difficult to treat successfully. This combination image can be done in one sitting, lowering the total cost of CNS scanning.

We will be validating these recommendations with the worldwide community of VHL clinical care centers and physicians treating people with VHL. Please share this information with your own team.

We will be happy to hear comments from families or physicians. Please send comments to editor@vhl.org.something here or a picture?

As printed in the VHL Family Forum 19:1, January/February 2011. For permission to reprint, please contact VHL Family Alliance, editor@vhl.org. Further information is available from the VHL Family Alliance, info@vhl.org.