[4] A zebrafish animal model with reduced GALNT3 expression also showed HFTC-like phenotype,[5] indicating an evolutionary conserved mechanism that is involved in developing tumoral calcinosis.

The name indicates calcinosis (calcium deposition) which resembles tumor (like a new growth).

They have propensity to enlarge progressively and ulcerate the overlying skin and extrude.

Laboratory evaluation reveal normal serum calcium levels and hyperphosphatemia.

Rarely ALP (alkaline phosphatase – an enzyme active at sites of bone formation) may be elevated.