Dermoids

Help! My child has a strange bump!

Lumps and bumps in children can be a source of alarm for parents. A sense of panic and fear that the lesion is a cancer is usually a first response. While cancers definitely do occur in children, they are very rare; however it is extremely important that cancer be ruled out. The specialists at the Craniofacial Team of Texas are experts in children with lumps and bumps and pediatric plastic surgery.

What causes these lumps or bumps?

As most parents know, humans have a lot of lumps and bumps.  Why is that?  Well, after an egg and a sperm fuse to form a single cell, zygote, a true miracle happens to form a baby. That one cell not only multiplies to form billions of cells, but they also start to take on very unique and different shapes and functions to make everything from an eyeball to a toe nail.  The sheer diversity of function of the various portions of the human body is mind boggling, and so it is not too surprising that sometimes some cells can go a little awry.  These cells do not behave and/or form the right structure or perform the right function.  In the young child, this is often discovered as an area that looks a little different, acts a little different, causes a mass or something noticeable.

If the tissue in question forms a very small “lump” or irregular area you may hear us call it a “lesion”.  If it forms a swelling or a “bump”, you may hear us call it a “mass”.  Most of the these things in children are very different from cancer, which is a clonal proliferation of cells that have lost their ability to control their replication, lost their original functional capabilities, and begin to spread outside the confines of their original anatomic boundaries.  While cancers definitely do occur in children, and we are involved in a great many of them, they are very, very rare.  For the most part, cancer is an older people’s phenomena.  That does not mean that lump and bumps, or lesions and masses, should be ignored.  They often expand with either cells or tissue fluids of one sort or another and cause harm by pressing on and destroying adjacent structures.  And sometimes they are just annoying and unsightly so we want to get rid of them. Some common benign lumps and bumps we treat at the Craniofacial Team of Texas are: congenital nevi, sebaceous nevi, dermoid cysts, atypical nevi, pilomatrixoma, epidermoid or sebaceous cyst.

What is a dermoid?

The term dermoid is very confusing because the Pathologists and Gynecologists often refer to a type of ovarian tumor as a

“dermoid”.  In reality, the ovarian tumor is a teratoma, but because some of the elements of the benign tumor for hair, nails and teeth (all derivatives of embryological ectodermal layer), the term dermoid has persisted.  The dermoid that we see in a child occurs in the periorbital region, between the eyes close the bridge of the nose, or on the scalp.  These represent true congenital malformations.  Cells that are forming skin elements are buried deep, usually around one of the joints between facial bones.

When the cells of a dermoid start forming skin under the surface, there is no place for the sloughing skin cells to go, so they start forming a cyst.  The most common area is the lateral orbital region.

Does my child need a CT scan or MRI?

Usually there is no need to image these lesions in the periorbital region, and it takes a fairly short procedure under anesthesia since we are working around the eye to remove it.  Imaging is sometimes needed if there is suspicion that the cyst has a “dumbbell” configuration with an intracranial (near the brain) extension; typically masses in the midline nasal region need an MRI because a higher percentage of these dermoids have deeper extensions.

Does my child need surgery?

Dermoid cysts NEVER go away by themselves and can cause erosion of adjacent tissues including the skull with penetration into the cranial cavity. We usually recommend surgery for excision within 2-3 months of diagnosis and if the patient is at least 4 months of age; removal near time of diagnosis reduces chance of rupture and disruption of involved tissues. If the cyst has an intracranial extension then surgery is more complex and usually requires a team approach with a neurosurgeon for excision. When the cyst is removed unruptured, the chance of recurrence is almost negligible. Care is taken not to rupture the cyst because the cyst contents can be highly inflammatory.