Tumors I & II (Swick)

Question 1

these two topical agents are used to treat actinic keratosis

Answer 1

topical 5-FU and Imiquimod

*Imiquimod is also indicated for the treatment of genital warts, and 5-FU when administered systemically is used for the treatment of colon cancer.

Question 2

Which of the following statements about squamous cell carcinoma is FALSE?

A. Most cases are due to chronic long term UV exposure

B. Histology shows keratin pearls.

C. Approximately half are attributed to a loss of function mutation in the hedgehog signaling pathway.

D. Risk of metastasis is low when recognized early.

E. A shave or punch biopsy is sufficient for diagnosis

Answer 2

C

This is basal cell carcinoma - loss of function in PTCH1 leads to loss of control of Hh signaling pathway. This loss of inhibition is demonstrated particularly in the hair follicle, which is dependent on Hh for signaling and harbors stem cells that then begin to proliferate out of control.

Question 3

histology of these epithelial lesions: pseudo-horn cysts opening to the surface and flat-bottomed epidermal thickening (acanthosis):

Answer 3

seborrheic keratoses

Question 4

histology shows elongated dermal papillae with a fibrotic or fatty core

Answer 4

acrochordons (skin tags)

*associated with weight gain, diabetes, and pregnancy

Question 5

nevi that are thought to arise from neural crest melanocytes that migrated to and stopped in the dermis (see below) instead of the epidermis during embryogenesis

Answer 5

blue nevi

Question 6

these lesions are derived from the infundibular (top) portion of a hair follicle, have “cheesy” appearing contents with an overlying punctum

Answer 6

epidermoid cysts

Question 7

histology shows:

• lots of blue, due to increased nuclear/cytoplasmic ratio
• mucin-stromal retraction
• lack of keratnization

Answer 7

basal cell carcinoma

Question 8

benign tumor of mature adipose tissue; no treatment necessary unless symptomatic

Answer 8

lipoma

*looks like epidermoid cyst, but is slightly softer and has no puntcum

Question 9

pink firm papules, often appearing on women’s shoulders or legs after minor localized trauma; characteristic dimpling when pinched (positive Fitzpatrick sign)

Answer 9

dermatofibromas

Question 10

most common skin cancer in caucasians that is locally destructive with low mortality, and is associated with a history of intermittent intense UV exposure

Answer 10

basal cell carcinoma

Question 11

disorder of hypopigmentation resulting from non-producing melanocytes

Answer 11

oculocutaneous albinism

Question 12

clinical presentation is varied, and may appear as:

• flesh colored pearly papules with arborizing blood vessels,
• crusted like psoriasis, or
• flat and discolored like a scar

Answer 12

basal cell carcinoma

Question 13

this is the most important prognostic factor in malignant melanoma

Answer 13

Breslow depth - measured from granular layer to deepest portion of melanoma with dermal invasion

*which is why a suspicious pigmented lesion needs to be biopsied into the fat; a full thickness punch biopsy or excisional biopsy will do

Question 14

acquired patchy depigmentation of skin due to absence of melanocytes, often around facial openings and sites of trauma (eg. elbows, knees, hands and feet)

Answer 14

vitiligo

Question 15

lentiginious hyperplasia (ie, melanocytic growth in a linear spread) with melanocytes spreading up the sides of rete ridges but not growing into the epidermis is characteristic of these nevi

Answer 15

dysplastic nevi

Question 16

pigmented or skin colored papules (rarely nodules) with symmetry and border regularity that are confined to the dermis

Answer 16

dermal nevi

Question 17

evenly pigmented papules (rarely nodules) that are found in both the dermis and epidermis, are flat-toppped, and have symmetry and border regularity

Answer 17

compound nevi

Question 18

symmetric flat macules confined to the epidermis with even pigmentation and regular borders

Answer 18

junctional nevi

Question 19

Which of the following statements about melanocytic nevi is FALSE?
A. They are benign accumulations of melanocytes that are usually acquired throughout childhood and young adulthood

B. Most nevi have BRAF and NRAS mutations

C. They tend to peak in number and size at age 40, then start to go away

D. They are considered true hamartomas - disorganized in their distribution but have normal cell cycle regulation

E. The number and type of nevi are secondary to genetic predisposition and early UV exposure

Answer 19

D.

Mealnocytic nevi are actually considered true neoplasms instead of hamartomas.

Question 20

“mask of pregnancy”; more common in darker skin types

Answer 20

melasma (chloasma)

Question 21

this is the second most common cause of skin cancer in Caucasians and is characterized by scaly erythematous papuls or nodules with a keratinous core or ulcer

Answer 21

squamous cell carcinoma

Question 22

histology of this lesion shows:

• keratinization
• no granular cell layer
• central compact pink keratin

Answer 22

trichilemmal (pilar) cysts

Question 23

All of the following statements regarding actinic keratosis are true EXCEPT:

A. It is an in-situ premalignant dysplasia of keratinocytes due to chronic sun exposure

B. 1 in 10 cases progress to basal cell carcinoma

C. It is characterized by a rough “sandpaper” feel when palpated

D. Histology shows less than full thickness epidermal atypia, with alternating para and ortho (hyper) keratosis

E. It is commonly caused by a p53 mutation

Answer 23

B. 1 in 10 cases will progress to squamous cell carcinoma.

Question 24

a subtype of melanoma in which chronic sun damage plays a big role

Answer 24

lentigo maligna melanoma

Question 25

benign proliferation of the epidermis, very common in people over age 30, waxy brown stuck-on appearing macules, papules and plaques

Answer 25

seborreheic keratoses

Question 26

everyone has at least one of these little guys by the time they’re in their 30s, but not PAs, we be goin backwards ya’ll

Answer 26

cherry hemangiomas

Question 27

these epithelial lesions result from activation of the transmembrane tyrosine kinase receptor FGFR3

Answer 27

sebhorreic keratoses

Question 28

All of the following are risk factors for melanoma EXCEPT:

A. Mutations in the CDKN2A gene (a kinase inhibitor)

B. 3 or more dysplastic nevi

C. Pale skin, red or blone hair, tan poorly/burn easily

D. Chronic UV exposure

E. Family history of melanoma

Answer 28

D.

Unlike squamous cell carcinoma, melanoma is associted with intense sun exposure in early life rather than chronic UV exposure

Question 29

histology shows: hyperpigmented, elongated rete ridges

Answer 29

solar lentigo

Question 30

these asymmetric “fried egg” nevi are not necessarily premalignant lesions, although when they appear in multiples they are a phenotypic marker for increased risk of developoing melanoma, especially with a family history

Answer 30

dysplastic nevi

Question 31

All of the following are characteristics associated with superficial spreading melanoma EXCEPT:

A. Early vertical growth phase

B. Upward spreading melanocytes

C. Lentiginous growth

D. Irregular nesting of melanocytes

E. Irregular color on skin

Answer 31

A. This is a characteristic associated with nodular melanoma, and is a negative prognostic factor of that type

Question 32

these immovable lesions are derived from the isthmus (middle) portion of the hair follicle, mostly occur on the scalp, and may be inherited in an autosomal dominant manner

Answer 32

trichilemmal (pilar) cysts

*NO punctum!

Question 33

All of the following are negative prognostic factors of melanoma EXCEPT:

A. Ulceration

B. High mitotic rate

C. Lymph node involvement

D. Regression

E. Inflammation in the tumor

Answer 33

E. This is a positive prognostic factor, indicating a vigorous host immune response to the tumor.