Cutaneous Mastocytoma : Intro & Clinical

Comments:
Solitary cutaneous mastocytoma (SCM) is a benign solitary collection of mast cells seen almost exclusively in children. It accounts for 10-20% of cases of mastocytosis. It is self-limiting and resolves spontaneously by puberty or can be cured by excision. Mast cell tumors are quite common in certain animals such as dogs and cats.

SCM is most often diagnosed in infants 0-3 months of age. It is rare in adults. It occurs as a solitary macule, nodule, or indurated plaque ranging in size from 1 to 2 cm. The surface may be pitted (peau d'orange appearance). It may be yellowish, red, pink, or brownish in color. In rare cases, there may be 2-3 lesions. It can occur at any site, although the most frequent location is the extremities - especially dorsum of hand and wrist (as shown in this photograph). Rare cases have been reported in lungs.

The lesion may itch and the patient may experience flushing attacks. Rubbing the lesion causes it to become red and swollen (positive Darier sign). Blistering may occur.