ABD - American Board of Dermatology Dermatologic Surgery Questions and Answers 1

Question 1

A 68-year-old male with a history of a renal transplant presents with a 2.5 cm, poorly demarcated, recurrent basal cell carcinoma on his left temple. The biopsy shows an infiltrative growth pattern. According to the Appropriate Use Criteria, which of the following is the most appropriate next step in management?

Accepted Answer

Mohs micrographic surgery

Answer

Mohs micrographic surgery is the standard of care for high-risk basal cell carcinomas. This patient has multiple high-risk features including a large size (>1 cm on the face), location in a high-risk anatomic area (temple), recurrent tumor, immunosuppression, and an aggressive histologic subtype (infiltrative). Mohs surgery offers the highest cure rate while maximizing tissue conservation, which is critical in this cosmetically sensitive area.

Question 2

A surgeon is planning to repair a 3 cm circular defect on the cheek of a 55-year-old patient following Mohs surgery. To achieve the best cosmetic outcome with minimal tension, which of the following local flaps is most suitable for this type of defect?

Accepted Answer

A rotation flap

Answer

A rotation flap is ideal for closing circular or triangular defects. It is designed by incising a curvilinear line from the edge of the defect, allowing a semicircular flap of tissue to pivot or 'rotate' into the defect. This technique is particularly effective on the cheek where there is sufficient skin laxity to allow for movement with good cosmetic results.

Question 3

Which of the following laser-tissue interactions is the primary mechanism for the selective destruction of a target chromophore, such as melanin in a pigmented lesion, while minimizing damage to the surrounding tissue?

Accepted Answer

Selective photothermolysis

Answer

Selective photothermolysis is the principle that allows for the specific targeting of a chromophore (e.g., melanin, hemoglobin). It requires using a wavelength of light that is preferentially absorbed by the target chromophore and a pulse duration that is shorter than the thermal relaxation time of that target. This confines the thermal energy to the target, causing its destruction with minimal collateral damage to surrounding structures.

Question 4

A 45-year-old patient undergoes cryosurgery with liquid nitrogen for a large, thick seborrheic keratosis on the back. Which of the following is the most common potential complication the patient should be counseled about?

Accepted Answer

Dyspigmentation

Answer

Dyspigmentation, particularly hypopigmentation, is the most common complication following cryosurgery. This occurs because melanocytes are very sensitive to cold injury and can be easily destroyed by the freezing process. While other complications like scarring, infection, and nerve damage can occur, they are less frequent than pigmentary changes.

Question 5

When repairing a large surgical defect, what is the primary advantage of using a local flap reconstruction compared to a full-thickness skin graft?

Accepted Answer

It maintains its own intrinsic blood supply.

Answer

The fundamental difference between a flap and a graft is the blood supply. A flap is tissue that is moved from a donor site to a recipient site while maintaining its own vascular pedicle, or blood supply. In contrast, a skin graft is completely detached from its blood supply and relies on the recipient bed for revascularization. This intrinsic blood supply makes flaps more robust and generally leads to better cosmetic outcomes.

American Board of Dermatology (ABD) Practice Test

American Board of Dermatology (ABD) Practice Test

ABD - American Board of Dermatology Dermatologic Surgery Questions and Answers 1