Chapter 10: Melanocytic Proliferations

QUESTIONS

QUESTION 10-1. A 30-year-old Caucasian male presents with multiple stellate brown macules on the shoulder after a severe sunburn from last summer. The lesions are all of about the same size and are sharply marginated. A biopsy is performed and the findings are illustrated below. Melan-A stain reveals a normal concentration of intraepidermal melanocytes. Which of the following diagnoses is CORRECT?

A) Pigmented actinic keratosis

B) Lentigo maligna melanoma

C) Solar lentigo

D) Junctional melanocytic nevus

E) Freckle

QUESTION 10-2. A young adult patient presents with a well-circumscribed, dark, uniformly pigmented macule on the shoulder. The lesion has been present for several years. A biopsy is performed and the findings are illustrated below. Melan-A stain reveals a slight increase in dendritic melanocytes along the basal layer. Which of the following diagnoses is CORRECT?

A) Lentigo simplex

B) Junctional nevus

C) Freckle

D) Primary acquired melanosis

E) Melanotic macule

QUESTION 10-3. Which of the following statements regarding benign acquired neoplastic melanocytic proliferations is INCORRECT?

A) Pigmented macules are typically histopathologically characterized by either lentiginous or nested melanocytes along the basal layer of the epidermis.

B) Pigmented papules are typically histopathologically characterized by nested melanocytes along the basal layer of the epidermis and within the dermis.

C) Lightly pigmented or flesh-colored papules are typically histopathologically characterized by nests of melanocytes within the dermis only.

D) The presence of mitoses in basal layer melanocytes indicates malignant transformation.

E) As melanocytes descend into the deeper aspects of the dermis, there is a shift in cellular morphology and gene expression toward neural differentiation.

QUESTION 10-4. A 35-year-old patient presents with a uniformly dark brown papule with well-circumscribed borders on the arm (Fig. 10-4 (A)...