Mr. Shukla, 35- year old man presents with 0.3-cm flat light brown lesion on his left forearm. The lesion is excised , and microscopy reveals nest of round nevus cells within the lower epidermis at the dermal –epidermal junction. There is no “fusion” present of the adjacent nests of nevus cells.
Cytologic atypia is not present , nor are seen in the superficial or deep dermis. Which of the following is most likely diagnosis? (AIIMS May 2013)
a. Melanocytic hyperplasia, which causes hyperpigmentation of the skin, can be classified into several types of lesions.
b. A lentigo consists of melanocytic hyperplasia in the basal layers of the epidermis along with elongation and thinning of the rete ridges.
c. Increased numbers of melanocytes may form clusters located at the tips of the rete ridges in the epidermis (junctional nevus), within the dermis (intradermal nevus), or both at the tips of the rete ridges and within the dermis (compound nevus).
d. A blue nevus is composed of highly dendritic melanocytes that penetrate more deeply into the dermis.
e. This deep location gives the lesion its characteristic blue color.
f. The Spitz tumor (epithelioid cell nevus) is a benign lesion composed of groups of epithelioid and spindle melanocytes and is found in children and young adults.
g. It may be mistaken histologically for a malignant melanoma.
h. A freckle (ephelis) is a pigmented lesion caused by increased melanin pig mentation within keratinocytes of the basal layer of the epidermis.
i. These lesions fade with lack of sun exposure.