In Texas, a biopsy taken from Kadynce was sent to three pathology labs before she was diagnosed with melanoma. In total, it took appropriately six weeks from when Royer first took her daughter to her pediatrician for Kadynce to receive her diagnosis.
Royer said she saw a pediatrician, dermatologist and plastic surgeon, all of whom first believed the spot was nothing to worry about and just a minor growth.
However, Royer said the plastic surgeon was the most concerned and biopsied her tumor. According to Royer, the initial lab test came back positive for melanoma, but the doctor wanted a second opinion. The second lab test came back with the recommendation that Kadynce be treated for a benign spitz nevus, the original diagnosis for John Randall. But Royer said Kadynce's plastic surgeon was concerned and sent the biopsy to a third lab, which finally confirmed that Kadynce had cancer.
"There is that immediate sense of relief that, 'Now we have an answer,'" said Royer. "You have 10 seconds to be sad and then you go to kick-butt-warrior mode."
'If You See Horses, You're Not Looking for Zebras'
Experts say that both Kadynce and John Randall's experiences of spending weeks to months of being misdiagnosed is fairly common. Melanoma in children often looks very different than melanoma in adults, often lacking the telltale irregularly pigmented moles. Even lab tests, like Kadynce's, can be inconclusive.
Dr. Ashfaq Marghoob, director of Memorial Sloan-Kettering's regional skin cancer clinic in Hauppauge, N.Y., and spokesman for the Skin Cancer Foundation, said melanoma presents very differently in children versus adults.
"You're asking these doctors to look for zebras," said Marghoob. "If you usually see horses you're not looking for zebras. Their mind is not in tune with looking for these melanomas. The morphology of melanoma in kids is different from adults."
A 2011 study presented at the Pediatric Dermatology Annual Meeting found that 60 percent of children between the ages of 0 and 10 in the study with melanoma did not meet the common melanoma-detection criteria. The criteria is broken down by the "ABCDE warning signs," which stands for Asymmetry, Border irregularity, Color variation and Diameter over six millimeters, and Evolution of the lesion.
For children between the ages of 10 and 20, approximately 40 percent did not strictly meet the ABCDE criteria.
Instead, many children in the study had tumors that were symmetrical and amelanosis (lacking pigment). The differences were so significant that the study's authors proposed creating alternative ABCD criteria for pediatric patients, where A is for amelanosis, B for bumps or bleeding, C for uniform Color, and D for various Diameters or de novo (or new) Development.
Marghoob cautioned that even when doctors look for the right warning signs, they can still have difficulty making the correct diagnosis. One problem is that in young children melanoma can be nearly difficult to distinguish from a benign spitz nevus, a kind of harmless mole.
"The clinical [and] the subclinical morphology, they overlap," said Marghoob. "There are features more commonly seen in melanoma in spitz nevus [and the other way around. Sometimes] one cannot, with 100 percent assurance, know if it's a spitz [nevus] or melanoma."