Skin Lesions, C63 P469-471

Question 1

What are the most common
skin cancers?
P469

Answer 1

1. Basal cell carcinoma (75%)
2. Squamous cell carcinoma (20%)
3. Melanoma (4%)

Question 2

What is the most common
fatal skin cancer?
P469

Answer 2

Melanoma

Question 3

What is malignant

melanoma?

Answer 3

A redundancy! All melanomas are

considered malignant!

Question 4

SQUAMOUS CELL CARCINOMA
What is it?
P469

Answer 4

Carcinoma arising from epidermal cells

Question 5

SQUAMOUS CELL CARCINOMA
What are the most common
sites?
P469

Answer 5

Head, neck, and hands

Question 6

SQUAMOUS CELL CARCINOMA
What are the risk factors?
P469

Answer 6

Sun exposure, pale skin, chronic
inflammatory process, immunosuppression,
xeroderma pigmentosum, arsenic

Question 7

SQUAMOUS CELL CARCINOMA
What is a precursor skin
lesion?
P469

Answer 7

Actinic keratosis

Question 8

SQUAMOUS CELL CARCINOMA
What are the signs/symptoms?
P469

Answer 8

Raised, slightly pigmented skin lesion;

ulceration/exudate; chronic scab; itching

Question 9

SQUAMOUS CELL CARCINOMA
How is the diagnosis made?
P469

Answer 9

Small lesion—excisional biopsy

Large lesions—incisional biopsy

Question 10

SQUAMOUS CELL CARCINOMA
What is the treatment?
P469

Answer 10

Small lesion ( < 1 cm): Excise with 0.5-cm
margin
Large lesion ( >1 cm): Resect with 1- to
2-cm margins of normal tissue (large
lesions may require skin graft/flap)

Question 11

SQUAMOUS CELL CARCINOMA
What is the dreaded sign of
metastasis?
P469

Answer 11

Palpable lymph nodes (remove involved

lymph nodes)

Question 12

SQUAMOUS CELL CARCINOMA
What is Marjolin’s ulcer?
P469

Answer 12

Squamous cell carcinoma that arises in an
area of chronic inflammation (e.g., chronic
fistula, burn wound, osteomyelitis)

Question 13

SQUAMOUS CELL CARCINOMA
What is the prognosis?
P470

Answer 13

Excellent if totally excised (95% cure rate);
most patients with positive lymph node
metastasis eventually die from metastatic
disease

Question 14

SQUAMOUS CELL CARCINOMA
What is the treatment for
solitary metastasis?
P470

Answer 14

Surgical resection

Question 15

BASAL CELL CARCINOMA
BASAL CELL CARCINOMA
What is it?
P470

Answer 15

Carcinoma arising in the germinating

basal cell layer of epithelial cells

Question 16

BASAL CELL CARCINOMA
What are the risk factors?
P470

Answer 16

Sun exposure, fair skin, radiation, chronic

dermatitis, xeroderma pigmentosum

Question 17

BASAL CELL CARCINOMA
What are the most common
sites?
P470

Answer 17

Head, neck, and hands

Question 18

BASAL CELL CARCINOMA
What are the signs/symptoms?
P470

Answer 18

Slow-growing skin mass (chronic, scaly);
scab; ulceration, with or without pigmentation,
often described as “pearl-like”

Question 19

BASAL CELL CARCINOMA
How is the diagnosis made?
P470

Answer 19

Excisional or incisional biopsy

Question 20

BASAL CELL CARCINOMA
What is the treatment?
P470

Answer 20

Resection with 5-mm margins (2-mm

margin in cosmetically sensitive areas)

Question 21

BASAL CELL CARCINOMA
What is the risk of
metastasis?
P470

Answer 21

Very low (recur locally)

Question 22

MISCELLANEOUS SKIN LESIONS
What is an Epidermal
Inclusion Cyst?
P470

Answer 22

EIC = Benign subcutaneous cyst filled
with epidermal cells (should be removed
surgically) filled with waxy material; no
clinical difference from a sebaceous cyst

Question 23

MISCELLANEOUS SKIN LESIONS
What is a sebaceous cyst?
P470

Answer 23

Benign subcutaneous cyst filled with
sebum (waxy, paste-like substance)
from a blocked sweat gland (should be
removed with a small area of skin that
includes the blocked gland); may become
infected; much less common than EIC

Question 24

MISCELLANEOUS SKIN LESIONS
What is actinic keratosis?
P471

Answer 24

Premalignant skin lesion from sun
exposure; seen as a scaly skin lesion
(surgical removal eliminates the 20% risk
of cancer transformation)

Question 25

MISCELLANEOUS SKIN LESIONS What is seborrheic keratosis? P471

Answer 25

Benign pigmented lesion in the elderly; observe or treat by excision (especially if there is any question of melanoma), curettage, or topical agents

Question 26

``` MISCELLANEOUS SKIN LESIONS How to remember actinic keratosis vs. seborrheic keratosis malignant potential? P471 ```

Answer 26

Actinic Keratosis = AK = Asset Kicker  premalignant Seborrheic Keratosis = SK = Soft Kicker = benign

Question 27

MISCELLANEOUS SKIN LESIONS What is Bowen’s disease of the skin? P471

Answer 27

Squamous carcinoma in situ (should be removed or destroyed, thereby removing the problem)

Question 28

MISCELLANEOUS SKIN LESIONS What is “Mohs” surgery? P471

Answer 28

``` Mohs technique or surgery: repeats thin excision until margins are clear by microscopic review (named after Dr. Mohs)—used to minimize collateral skin excision (e.g., on the face) ```