WARNING: This post may be deep!!
Today we had the official first full day of the conference. First we had Nevus 101 Part 1! Dr. Ashfaq Marghoob spoke about CMN (Congenital Melanocytic Nevus...which is the long name for a nevus). He talked about the size of them: Small, Medium, Large, Giant. They will grow in proportion to the child. For example, Brooklyn's nevus was 9cm x 10cm at birth. At 2 months it was 10cm x 11cm. I need to measure it again b/c I'm sure it's bigger by now. The risks of having a CMN include: melanoma, NCM (neurocutaneous malanocytosis), tumors, and cosmetic issues. 1:100 births have a small CMN, 1:1000 births have a medium; 1:20,000 births have a large; and 1:500,000 have a giant. CMN's form in the neural crest in the cells at a very early gestation. There is a melanocytic cell in the neural crest that goes thru the meninges in the brain and spinal cord then to the skin and that's when the skin gets pigmented. The lightness/darkness is dependent on how far towards the skin surface it is. If it's ventral then it goes on the neural route so it'll be larger and thicker. The gene that they're talking about is the C-met-proto oncogene. There COULD be a genetic component, but for it to manifest is a total chance occurrance. Symptoms of a CMN include: decreased sweating, pruritis (itching), exzema, and skin fragility. 1/3 of Large CMN's become lighter. Often scalp nevi's will disappear, BUT the nevi cells are still present...so they still do need to be removed. A large CMN has a 1%-10% risk of becoming malignant...which means that 90% won't turn cancerous. 7% of the patients studied got melanoma. 3% of people who had a truncal nevus got melanoma and just 1% of people who had a head/limb nevus got melanoma. Most turn cancerous by age 5. NCM is neurocutaneous melanocytosis. This is when deposits on the skin go to the brain. Of the people who have a CMN, 5%-22% develop NCM. The risk is higher if they have a lot of satellites. Satellites are like mini-CMN's and they can occur all over the body. People can have anywhere from several to thousands. The larger the nevus, the larger the risk is of developing NCM. 1% of people with head nevi's get NCM and 0% have died from this. They have a 5x greater risk of getting NCM if the nevus is on their spine or they have more than 20 satellites. The number of satellites determines the risk, NOT the location of the satellites. For the risk of melanoma: the size - the larger the nevus the greater the risk; torso has a greater risk; satellites aren't important (no melanoma has ever been reported in a satellite). For the risk of NCM: the size - the larger the nevus the greater the risk; location is not important; the greater the number of satellites the greater the risk. 76% of patients prefer a scar over the nevus; 74% believe that scars are more socially acceptable; and 24% regretted ever having surgery. Surgical excision of the nevus doesn't reduce the risk of melanoma to zero, but it significantly decreases the risk. Residual cells remain and melanoma cells can develop from these.
Nevus 101 Part 2: Veronica Kinsler from the Great Ormond Street Hospital for Children in London spoke next. She answered a very important question: Was it something I did to cause my child's nevus? Answer is NO! A positive correlation of mom's with nevus babies include: pre-eclampsia, threatened miscarriage, severe nausea & vomiting, and smoking. I never had any of these myself! The size of the nevus depends on how early in gestation the change happend with the neural cells and the melanocytes.
Next speaker was Yasmin Khakoo, MD from the Memorial Sloan-Kettering Cancer Center in NY, NY. She said that 7% of kids with a large CMN have NCM. Neurological complications from NCM include: hydrocephalus (water on the brain - caused by an inability for the brain to absorb water like it should b/c the melanocytes are in the way, basically), seizures, developmental/behavioral issues, cranial nerve issues, and spinal nerve root/cord compression. Recommends an MRI before 4 months of age with a GRE sequence (gradient echo). If a child gets CNS (central nervous system) melanoma that is fatal....and also rare.
Research Update Part 1: Dr. Sven Krengel - dermatologist from Germany. Classifies Giant CMN as greater than 1% of body if it's on the head/face - which Brooklyn's is. Laser and dermabrasion are not recommended treatment options for nevi's.
Next speaker: Dr. Miguel Reyes from the Children's Hospital in Pittsburgh and he talked about the role of the pathologist. There's diagnostic or research pathology. 3 types of nevi's: epiderman, melanocytic, and connective tissue.
Research Update Part 2: Veronica Kinsler again about research done on facial features of kids with CMN. Very interesting! Children with congenital menanocytic nevi's DO look alike. This is a confirmed, extended study done in England. They all have a broad, round face, wide forehead, eyebrow changes, fullness around the eyes, short nose, broad lips, full cheeks, long/deep philtrum, prominent lower lip, broad face, and are attractive. There's question whether or not to call this CMN Syndrome.
Next speaker: Heather Etchevers spoke about Nevus Development, Molecular Genetics, & You.
Next speaker: Bernard Wehrle-Haller from the Univ of Geneva, Switzerland spoke about Controlling the Replication of Melanocytes.
WHEW! Very exhausting, informative day!