Nomenclature in macrocephaly–capillary malformation Syndrome


M-CM Network, PO Box 97, Chatham, NY 12037. E-mail:

To the Editor

I am writing as a representative for an advocacy organization for macrocephaly–capillary malformation syndrome, the M-CM Network, regarding a article published in this journal.

“Megalencephaly–capillary malformation (MCAP) and megalencephaly–polydactyly–polymicrogyria–hydrocephalus (MPPH) syndromes: Two closely related disorders of brain overgrowth and abnormal brain and body morphogenesis” by Mirzaa et al. [2012]. This article compares M-CM and MPPH syndromes, which both have megalencephaly as a characteristic. Included in this article is the proposal to rename M-CM from “macrocephaly–capillary malformation” to “megalencephaly–capillary malformation” with a new abbreviated name of MCAP.

The subject of the article is not nomenclature, but this detail has significant implications for M-CM patients. M-CM was first identified in 1997 and at that time was called macrocephaly-cutis marmorata telangiectasia congenita or M-CMTC. In 2007, the current name was proposed because the initial name did not accurately describe the skin markings in M-CM.

The proposed new name, which would be the third for the syndrome since 1997, does not correct an inaccuracy, and we feel that it introduces unnecessary chaos into the business of caring for people with M-CM. From our perspective, there is no problem that this name change solves. In fact, we think that a search on “macrocephaly” is more likely to be performed by someone looking for a diagnosis since “megalencephaly” would only be determined as a result of imaging. We see no reason to change the abbreviation from M-CM to MCAP.

A version of this letter appears on our website and parents of affected children have posted concerns:

“Another name change would make directing people through my son's medical history even more complex. I think I would also end up having to explain to most of my son's care providers (who are mostly not concerned with neurology/neurosurgery) what megalencephaly means … whereas they usually understand macrocephaly without any further explanation.”—Lorraine Yeomans

“As a parent of a child with M-CM, I have read this article with a heavy heart. My son, after many misdiagnoses, was diagnosed with M-CMTC in 2004 when he was 9 years old. Although here in the UK there are a growing number of children and young adults being “re-diagnosed”, I for one am finding the condition not widely known by the medical staff that we deal with. Even now my son is 15, and we have had this diagnosis for 6 years I still find myself having to explain every aspect of M-CMTC to most professionals that we encounter.”—Heidi Frost

“I think my biggest concern about another name change is families and physicians not finding the information they need on the diagnosis. I know many families including our own have done self diagnosis of their children on the internet. If I had not found the older M-CMTC website, my son would have gone on without a diagnosis and appropriate treatment. Still I have physicians that are confused about the diagnosis and I refer them to the M-CM Network website. Another name, more confusion. I have found there really is no formal process that any researcher has to go through to change a syndrome name. No peer review, no consensus.”—Leslie Sanderson

It is our opinion that the purpose of a name is to serve as a stable placeholder for discussion of something, and changing the name again subverts that purpose, causing confusion and problems for patients and for the people who care for them. It may be worth reconsidering the current preference in the medical genetics community of naming newly understood syndromes with descriptive names. Perhaps providing an accurate description of any genetic syndrome that affects multiple body systems and whose natural history is ill-defined is too much to ask of a name.

While we greatly respect the research of the authors of this article, we hope that researchers and clinicians do not adopt this new proposed name and continue to use M-CM, macrocephaly–capillary malformation.