A 32-Year-Old Man Comes for Evaluation of a Bump on the Right

question 51

Multiple Choice

A 32-year-old man comes for evaluation of a bump on the right side of his chest.  He initially noticed it 4 months ago, and it has grown slightly larger in the past month.  The patient has not experienced any trauma to the area or recent surgeries.  He does not use tobacco or alcohol.
Skin examination is shown below.  There is no drainage from the lesion or tenderness to palpation.  The lesion does not change in shape when pinched at the edges.  The remainder of his physical examination is within normal limits.

Which of the following is the most likely diagnosis?

• A)Acne vulgaris
• B)Dermatofibroma
• C)Epidermal inclusion cyst
• D)Lipoma
• E)Pyogenic granuloma

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Definitions:

Active Transport

Transport of molecules across the membrane of a cell from areas where they are less concentrated to areas where they are more concentrated, which demands energy.

ATP

Adenosine triphosphate, a molecule that stores and transfers energy within cells, facilitating various biochemical processes.

Concentration Gradient

A difference in the concentration of a substance across a distance, which drives the passive movement of particles from an area of high to low concentration.

Exocytosis

A process by which cells release substances to the external environment by vesicles fusing with the plasma membrane.