8 Cut Malignancies Flashcards

(134 cards)

1
Q

1 What are the layers of the epidermis from super ficial to deep? (▶ Fig. 8.1)

A
  • Stratum corneum (cornified layer)
  • Stratum granulosum (granular layer)
  • Stratum spinosum (spinous layer)
  • Stratum germinativum (basal layer)

The dermis is immediately deep to this.

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2
Q

2 Name the four cell types of the epidermis.

A
  1. Keratinocytes (80%)
  2. Merkel cells (mechanoreceptors)
  3. Langerhans cells (antigen processing and presenting cells)
  4. Melanocytes (pigmented dendritic cells)
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3
Q

3 What is the “H-zone” of the head and neck? (▶ Fig. 8.2)

A

This area extends vertically from the angle of the mandible through the ear and preauricular region to the temple and is connected horizontally through the periorbital skin, nasal skin, and upper lip.

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4
Q

4 Which skin cancer type is most common on the lower lip?

A

Squamous cell carcinoma

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5
Q

5 What risk factors are associated with lymphatic metastasis of cutaneous squamous cell carcinoma?

A
  • Area > 20 mm (less in the H-zone)
  • Depth > 5 mm or subcutaneous fat
  • Recurrent tumors
  • Site of prior radiation or scar
  • Rapidly growing tumor
  • Poorly differentiated tumors, high-grade tumors
  • Perineural invasion; Lymphovascular invasion
  • Immunosuppression
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6
Q

6 Metastasis from cutaneous head and neck squamous cell carcinoma most commonly occurs in which lymphatics?

A

75% of cutaneous lymphatic metastases occur in the parotid bed

40% occur in Level II.

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7
Q

7 What are risk factors for cutaneous squamous cell carcinoma of the head and neck?

A
  • Ultraviolet radiation is the number 1 risk factor
  • Light skin pigmentation
  • Ionizing radiation
  • Immunosuppression
  • Exposure to coal tar, asphalt, and arsenic consumption
  • Xeroderma pigmentosa, basal cell nevus syndrome
  • Tendency to burn or freckle (rather than tan)
  • Male sex
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8
Q

8 Describe the Fitzpatrick scale.

A

Classification schema for the color of skin. Associated with decreasing risk of cutaneous malignancy:

  1. Type I: Pale white, blond, or red hair; blue eyes; always burns, never tans; freckles
  2. Type II: White, fair, blond or red hair; blue, green, or hazel eyes; tans minimally, often burns
  3. Type III: Fair skin; any hair and eye color; tans evenly, sometimes burns.
  4. Type IV: Mediterranean skin, rarely burns, tans easily
  5. Type V: Dark brown skin, rarely burns, tans easily
  6. Type VI: Dark brown to black, never burns, tans very easily
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9
Q

9 What are the risk factors for development of solar keratosis, how many of these eventually undergo malignant transformation, and what percentage of squamous cell carcinomas can be traced to actinic keratosis?

A

Sun exposure is the most important risk factor, but immune suppression is also important (immune-suppressed individuals are 250 times more likely to develop solar keratoses). Fewer than 1/1,000 solar keratoses will go on to become squamous cell carcinoma; 60% of squamous cell carcinomas can be traced back to solar keratoses.

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10
Q

10 What is Marjolin ulcer?

A

Ulcerative squamous cell carcinoma at the site of prior trauma, inflammation, or scarring such as radiation or a burn.

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11
Q

11 What percentage of nonmelanoma cutaneous malignancies are made up of squamous cell carcinoma?

A

20%

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12
Q

12 Which pathologic finding in squamous cell carcinoma is associated with the highest recurrence rate and regional metastasis?

A

Perineural invasion. This is associated with metastasis in 47% of patients.

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13
Q

13 How many solar keratoses eventually undergo malignant transformation?

A

Fewer than 1 in 1,000 solar keratoses will become squamous cell carcinoma.

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14
Q

14 What percentage of squamous cell carcinomas can be traced to actinic keratosis?

A

60%

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15
Q

15 Describe the clinical and pathological characteristics of Bowen disease.

A

Bowen disease is an intraepidermal squamous cell carcinoma that manifests as an enlarging, well-demarcated erythematous plaque with surface crusting. Histologically, it resembles squamous cell carcinoma with atypical keratinocytes replacing epidermis. It appears more commonly in women (70 to 85%) and in the sixth or seventh decades of life. It can appear anywhere, but it is more common in the lower legs. The cause has been traced to sun exposure, arsenic, immune suppression, and viral infection.

Treatment is most often provided with cryotherapy, curettage, excision, laser, photodynamic therapy and topical 5-fluorouracil (5-FU), with no treatment showing a clear superior effect.

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16
Q

16 What type of skin cancer is known for rapid progression of a swelling, dome-shaped lesion that eventually resolves by sloughing off and scarring?

A

Keratoacanthoma

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17
Q

17 Your patient, a 67-year-old farmer, has a rapidly expanding, symmetric, dome-shaped lesion on his neck. The lesion is surrounded by smooth, inflamed skin, but it has a central crater containing keratinous debris. What is the most likely diagnosis?

A

Keratoacanthoma

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18
Q

18 Describe the typical manifestation of a keratoacanthoma.

A

Keratoacanthomas are rapidly growing lesions that may then slowly spontaneously involute after a plateau phase.

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19
Q

19 Describe the typical manifestation of cutaneous squamous cell carcinoma.

A

A thick, scaly patch, an ulcerated patch with rolled borders, a nodular lesion, or scale with pigmentation

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20
Q

20 What symptoms should be elicited in an history of present illness for a patient with newly diagnosed cutaneous squamous cell carcinoma?

A

Symptoms of advanced disease: numbness, pain, weakness or other perineural symptoms; weight loss, bone pain, shortness of breath to suggest distant disease; rapid growth, bleeding, fixation, neck mass to suggest locally advanced or aggressive disease

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21
Q

21 What features of cutaneous squamous cell carcinoma merit radiologic workup?

A
  • Locally advanced disease: Fixation, numbness, weakness, pain or trismus, extensive lesions (> 2 cm), or perineural or lymphovascular invasion
  • Regionally advanced disease: Palpable lymphadenopathy, in transit metastasis
  • Distant metastasis risk: Axillary adenopathy, bone pain, shortness of breath, unexplained weight loss, unexplained neurologic symptoms
  • High-risk patients: Recurrent lesions, immunosuppression, history of radiation
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22
Q

22 What is the most appropriate biopsy technique for deep ulcerated lesions of the skin of the head and neck?

A
  • Punch of incisional biopsy at the thickest portion of the lesion
  • Full-thickness biopsy should be attempted and should involve the reticular dermis or subcutaneous fat when possible.
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23
Q

23 What features of head and neck nonmelanoma skin cancer are associated with American Joint Committee on Cancer (AJCC) T2 tumors?

A

>2 cm greatest dimension or Two or more high-risk features:

  • > 2-mm invasion
  • Clark level ≥ IV
  • Perineural invasion
  • Primary site ear
  • Primary site non-hair bearing lip
  • Poorly or undifferentiated tumor

Note: Excludes cutaneous squamous cell carcinoma of the eyelid

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24
Q

24 What features of head and neck nonmelanoma skin cancer are associated with T3 and T4 tumors (AJCC seventh edition)?

A
  • T3: Invasion of the maxilla, mandible, orbit, or temporal bone
  • T4: Perineural invasion of the skull base
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25
25 What are the high-risk features of head and neck cutaneous squamous cell carcinoma?
* Deep lesions (\< 2 mm, Clark level IV) * Perineural invasion * H-zone lesions * Recurrent lesions Lesions arising in radiated fields or scar * Size \> 1.5 cm * Poorly differentiated lesions * Immunosuppression
26
26 What locations of head and neck cutaneous squamous cell carcinoma are more likely to exhibit recurrence and why?
High-risk sites for recurrence include the so-called **H-zone** along the preauricular and postauricular areas as well as across the midface, including the nose. This has been attributed to these sites being **the location of embryologic fusion**, affording tumors planes that **provide avenues for spread**.
27
27 True or False: Pathologic involvement of neck nodes with metastatic cutaneous squamous cell carcinoma is associated with worse survival in patients who also have parotid metastasis.
True. Andruchow et al 2006
28
28 What are appropriate margins for low-risk cutaneous squamous cell carcinoma?
4- to 6-mm clinical margins.
29
29 Although not yet approved by the Food and Drug Administration (FDA), **imiquimod** has shown some promise of utility for the treatment of cutaneous squamous cell carcinoma. What is the mechanism of action for imiquimod?
A local immune response modifier that induces activity of **interferon-α** and other cytokines.
30
30 Describe the technique for electrodessication and curettage (EDC) used in cutaneous squamous cell carcinoma and basal cell carcinoma.
In EDC, a curette is used to scrape tumor off **down to the dermis**, following which an **electrodessication is performed to denature any cells along the surface**. This is repeated til a satisfactory depth of excision is reached
31
31 When is Mohs surgery indicated for cutaneous squamous cell carcinoma of the head and neck?
* Anatomically or aesthetically sensitive areas where wide margins are not achievable (periorbital, nasal, periauricular and auricular, and perioral) * Positive margins after wide local excision and potential extension into an area fulfilling the first criteria
32
32 When is radiation indicated for cutaneous squamous cell carcinoma?
* Nonoperative candidates (surgical risk or unresectable) * Positive margins or incomplete excision * Solitary node ≥ 3 cm or with extracapsular extension * Multiple positive nodes * Multiple recurrent disease despite appropriate treatment * Perineural invasion of major (named ) nerve or extensive perineural invasion * T4 disease
33
33 What is the appropriate treatment of keratoacanthoma?
* Wide local excision is preferred * Intralesional methotrexate, steroids, and 5-FU can be used for nonoperative cases.
34
34 What proportion of BCCs occur on the head and neck?
80%
35
35 Is upper lip cancer more common in men or women?
It is more common in **women**: 21% of lip cancers on the upper lip versus only 3% of lip cancer in men.
36
36 What percentage of cutaneous malignancies occur on the lower lip?
90%
37
37 What is the significance of BCC found in the folds of the face?
These tumors develop at the site of **embryonic fusion plates**, resulting in more likely **recurrence** and **higher risk of spread**. They therefore require close follow-up.
38
38 Is BCC more likely on the upper or lower lip?
Upper lip (13% vs. 1% of lower lip cancers)
39
39 What is the likelihood of regional nodal metastasis in BCC?
Nodal spread is **rare**, occurring in \<0.5%
40
40 What is the mechanism by which ultraviolet (UV) B-wave light damages skin?
UV light in the B-band **(280 to 320 nm)**, which is the same wavelength responsible for sunburn, causes direct damage to DNA by exciting DNA molecules, resulting in **covalent bonds between adjacent cytosine bases**. These dimers are read as "AA" by DNA polymerase, and therefore the **corresponding "TT" is added to the growing strand**.
41
41 What are the risk factors for BCC?
**Sun exposure** is the most important risk factor, with other factors including lightly pigmented skin, blue or green eyes, and white ethnicity. Certain genetic conditions also predispose individuals to basal cell carcinoma, including **basal cell nevus syndrome** (also called **Gorlin syndrome**) and **xeroderma pigmentosum**. Exposure risks include tanning beds, arsenic, prior trauma, ionizing radiation, and immune suppressants.
42
42 What are the so-called high-risk features used in staging of BCC?
* Poor differentiation * Perineural spread * Origination in the ear or the hair-bearing lip * Depth \> 2 mm * Clark level IV or V invasion
43
43 What percentage of nonmelanocytic cutaneous neoplasms are BCC?
80%
44
44 What are the most commonly described types of BCC?
There are **26 different subtypes** of basal cell. The following are the most commonly described: 1. **Nodular** is the MC form of BCC (80%), often described as pearly with rolled borders and occasionally central ulceration. 2. **Morpheaform** (or sclerosing or fibrosing) has irregular borders on yellow plaques and is the _most aggressive_ type of BCC, with higher recurrence and worse prognosis. 3. **Fibroepithelial** 4. **Superficial** is most common type on the trunk, irregularly shaped, waxy, and with an occasionally eczematous or psoriatic appearance. 5. Other commonly described types are **pigmented** and **micronodular**.
45
45 What percentage of BCC are nodular?
80%
46
46 Which subtype of BCC has the youngest average age at initial diagnosis?
**Superficial**, which is more common on the trunk
47
47 What aspect of **morpheaform** tumors render them able to spread along embryogenic fusion planes and therefore makes them more aggressive with worse prognosis?
Morpheaform tumors secrete **collagenases**, enabling movement between anatomic subsites.
48
48 Which subtype of BCC is much more common in patients of African and Chinese descent than those that are found in white patients?
**Pigmented** BCC
49
49 Describe the clinical constellation known as **nevoid basal cell carcinoma syndrome** (or **Gorlin syndrome**)
Patients are diagnosed at an early age with multifocal basal cell carcinomas, **odontogenic keratocysts (keratocystic odontogenic tumor)**, and often also bifid ribs, scoliosis, developmental delay, and frontal bossing.
50
50 Describe the characteristic features of nodular BCC.
Classically, nodular BCC is described as a **pearly lesion with rolled borders, central ulceration, and peripheral telangiectasias**
51
51 Describe the features associated with **arsenic** exposure.
* Truncal BCC * Keratoses of the palms and soles * Nail changes (Mees lines)
52
52 What type of biopsy should be performed for a suspected BCC?
**Shave biopsy** is appropriate for the vast majority of BCC. When lesions are **_pigmented_**, **a punch biopsy** should be performed to assess the depth of the lesion.
53
53 When is imaging required in BCC?
Rarely: Large tumors, suspicion of invasion of deeper structures (e.g., fixation, bone invasion), symptoms of perineural invasion, palpable lymphadenopathy
54
54 What parts of the head and neck are at highest risk of recurrence when affected by cutaneous malignancies?
The preauricular and postauricular regions, floor of nose/columella, medial and lateral canthi, nasolabial fold, aka the so-called **H-zone**
55
55 Under what circumstances should cryosurgery be considered for management of BCC?
Cryosurgery can be used in **small (\< 1 cm)** nonaggressive tumors.
56
56 In the management of BCC, what tumor attributes favor excisional curettage and electrodessication?
**Small (\< 2 cm)**, nonaggressive tumors can be removed with excisional curettage with 90% success. Excisional curettage is not optimal for management of functionally and cosmetically important tumors.
57
57 What rate of cure can be expected with Mohs surgery in BCC?
96 to 99% cure rate in **recurrent** and **primary** resections, respectively
58
58 What are the advantages of Mohs surgery over simple excision with electrodessication?
* Maximal preservation of normal tissue * Optimization of functional/cosmetic outcomes * Assessment and clearing of entire margin * Lower recurrence rates * Immediate reconstruction (usually) * Only one practitioner involved at all phases of management
59
59 What are the nonsurgical options for management of BCC?
* Radiation therapy (MC, although waning in popularity) * Photodynamic therapy * Immunotherapy * Chemotherapy * **Vismodegib**, an agent that targets the **hedgehog signaling pathway** and was approved in 2012 for treatment of basal cell carcinoma
60
60 In patients with cutaneous BCC, when should neck dissection be considered?
Neck dissection should be used only in instances when there is **clinical evidence of nodal metastasis** because BCC metastasizes to the lymph nodes in **only 0.5% of cases.**
61
61 Why is it best to defer reconstruction in the **morpheaform type** of BCC?
Morpheaform BCC classically exhibits **subdermal spread** that results in **more common recurrence** than other variants of BCC. Reconstruction either with grafting or tissue rearrangement may cover this subdermal extension and delay diagnosis of recurrence, sometimes with devastating consequences for the patient.
62
62 What percentage of mucosal melanomas present in the head and neck?
55%
63
63 What is the most common head and neck site where mucosal melanoma is found?
Nasal cavity
64
64 Where do most melanomas arise?
* Most melanomas arise on the trunk and extremities. * **Nodular melanoma** and **lentigo maligna melanoma** more commonly occur in the head and neck than other subtypes.
65
65 What is the incidence of lymphatic metastasis in malignant melanoma?
Incidence varies by subtype, depth, and location. * \< 0.75 mm: \< 5% * 0.75 to 4.0 mm: 20% * \>4.0 mm: 30% Incidence increases with ulceration, nodular type, Clark level IV or V, and elevated mitotic rate.
66
66 What is the metastatic rate of **desmoplastic melanoma**?
**Pure desmoplastic melanoma** displays regional lymph node involvement in 2% of cases, whereas **mixed desmoplastic melanoma** has regional lymph node involvement in 20%. Distant metastasis is similar in the two subtypes, at 12%.
67
67 How has the incidence of melanoma changed in the United States in the last 30 years?
* It has seen a **threefold increase** in the white population. * The rate has been stable in the black population
68
68 What are the risk factors for cutaneous melanoma?
* Personal or Family hx melanoma * Lightly pigmented skin, red hair * Tendency to burn * DNA repair defects (e.g., xeroderma pigmentosum) * Chronic and intense sun exposure * Equatorial residence, tanning bed use * Immunosuppression * \> 100 melanocytic nevi, \> 5 atypical melanocytic nevi * Multiple solar lentigines
69
69 What familial autosomal dominant disorder greatly increases the risk of melanoma?
Atypical mole syndrome
70
70 What are the common subtypes of cutaneous melanoma?
* Superficial spreading (57%) * **Nodular melanoma (21%)** * **Lentigo maligna (9%)** * Acral lentiginous (4%) * Unclassifiable (4%) * Other (5%)
71
71 What sizes of congenital nevus have an increased risk of developing into melanoma?
Giant congenital nevus (2 cm or larger)
72
72 What is the most common histologic subtype of melanoma?
Superficial spreading (57%)
73
73 What is the second most common histologic subtype of melanoma and the most aggressive subtype?
Nodular melanoma (21%)
74
74 What differentiates **lentigo maligna** from **lentigo maligna melanoma**?
Lentigo maligna melanoma has **invasion** into the dermis.
75
75 What subtype of melanoma is found on the soles of feet or palms of hands?
Acral lentiginous (4%)
76
76 Which melanoma subtype is considered the least aggressive?
**Lentigo maligna melanoma (9%)**. It displays a long radial growth phase relative to other subtypes
77
77 What are the most common genetic aberrations found in melanoma?
* Chronic sun-damaged skin: KIT \> KIT + NRAS = BRAF = NRAS * Nonchronic sun-damaged skin: **BRAF** \> \> NRAS * Mucosal: **KIT** \> \> NRAS
78
78 What are the ABCDEs of melanoma?
* A = asymmetry * B = border irregularity * C = color variability * D = diameter greater than 6 mm * E = evolving over time
79
79 What is the clinical evaluation that all patients with newly diagnosed melanoma should receive?
Full-body skin examination, including hair-bearing areas and intertriginous areas, and examination of the relevant lymph node basins
80
80 When should imaging be performed in malignant melanoma?
* Extensive primary (fixation, perineural symptoms) * Abnormal or equivocal adenopathy * Stage III or greater disease * Specific signs or symptoms to suggest metastatic disease
81
81 What is the most ideal method to obtain a biopsy of a lesion suspicious for melanoma?
**Narrow-margin excisional biopsy** with **adequate depth** to determine accurate Breslow depth
82
82 What histopathologic markers are commonly used to identify melanoma?
* Homatropine methylbromide (HMB-45) * S-100 protein * Melan-A (MART-1)
83
83 What is the preferred evaluation of **suspicious lymphadenopathy** in patients with cutaneous melanoma?
**FNA** with or without ultrasound. Equivocal adenopathy can be evaluated with ultrasound. Suspicious adenopathy should be biopsied. A normal ultrasound does not replace sentinel lymph node biopsy.
84
84 What are potential sites for occult primaries in patients with metastatic melanoma of the head and neck?
Ocular, mucosal, EAC, hair-bearing areas, or tumor regression
85
85 Describe the Clark levels for melanoma staging. (▶ Fig. 8.3)
1. Level I: Epidermis only 2. Level II: Through basal cell layer into papillary dermis 3. Level III: Fills papillary dermis, to junction with reticular dermis 4. Level IV: Involves reticular dermis 5. Level V: Subcutaneous tissue
86
86 What is the stage of a 2-mm-thick melanoma without ulceration?
T2a, stage IB
87
87 What are the M stages of melanoma metastasis? (▶ Table 8.1)
* M1a: Metastatic melanoma to dermis * M1b: Metastatic melanoma to the lung * M1c: Metastatic melanoma to other visceral organs or abnormally **elevated LDH**
88
88 What is the most common site of melanoma metastasis?
Regional lymph nodes
89
89 How does mitosis impact T stage in cutaneous melanoma?
T1 lesions with one or more mitoses/mm2 are T1b.
90
90 How does ulceration impact T stage in cutaneous melanoma?
Lesions ulceration are upstaged to **b** (i.e., T1a vs. T1b)
91
91 What differentiates Stage III A, B, and C disease in cutaneous melanoma?
* IIIA: Any T-a and N-a (i.e., T4aN2a) * IIIB: One of T or N is a, one is b (i.e., T4aN2b or T4bN2b) or any T1–4aN2c * IIIC: Any T1–4b and N1–2b or N2c or any TN3 (i.e., T1bN2b or T1aN3) All must be M0 (M1 = stage 4)
92
92 What is the lifetime risk of developing a second primary melanoma?
8%
93
93 In localized melanoma, what is the most important prognostic factor?
Tumor thickness (Breslow depth of invasion)
94
94 What is the most significant prognostic factor in patients with stage III melanoma?
Presence of in-transit metastasis or in-satellite metastasis
95
95 What are the respective 5-year survival rates for melanoma patients with positive and negative sentinel lymph nodes?
56% vs. 90%
96
96 What is the 5-year survival for a patient with metastatic melanoma?
20%
97
97 What serum factor is an independent predictor of survival in stage IV metastatic melanoma?
LDH. Adds a suffix for M stage.
98
98 What is the treatment of choice for superficial thickness melanomas (\< 1.01 mm)?
Wide local excision with 1 cm margins This is T1 T1a: \<0.8 mm w/o ulceration T1b: \<0.8 mm w ulceration; 0.8-1.0 mm w/o ulceration
99
99 When should sentinel lymph node biopsy be considered in melanoma?
Primary tumor that is T2 or greater and/or Clark level IV T2 is 1.01-2.0 mm thick (a no ulcer; b ulcer) Clark's lev IV is involving reticular dermis
100
100 What is the treatment of choice for intermediate thickness melanomas (1.01 to 4.00 mm)?
Wide local excision with 2-cm margins and sentinel lymph node biopsy If N1-N3 neck: neck dissection (may require superficial parotidectomy), may consider chemo)
101
101 What is the treatment of choice for deep thickness melanomas (\> 4.00 mm)?
Wide local excision with 2-cm margins down to fascia and sentinel lymph node biopsy
102
102 Which chemotherapeutic agent is approved for treatment of stage IV melanoma?
Dacarbazine
103
103 What is the treatment of choice for melanoma involving the auricle?
Wide local excision
104
104 What adjuvant therapy is approved for use after surgery for stage III melanoma?
Interferon-α2b
105
105 What is the recommended treatment for Spitz nevus?
In many instances, **Spitz nevus** is difficult to distinguish from melanoma even for experienced pathologists. Therefore, complete excision is essential.
106
106 What are the contraindications to methylene-blue dye injection?
* Previous hypersensitivity * Pregnancy * Concurrent use of SSRI or other serotonergic drugs (serotonin syndrome) * Glucose-6-phosphate dehydrogenase deficiency
107
107 What are the most common complications associated with Mohs surgery?
Complication rates in Mohs surgery are quite low, with **hematoma** and **graft necrosis** being among the most common.
108
108 Merkel cell carcinoma is what type of tumor?
**Neuroendocrine.** It arises from Merkel cells, which are specialized _touch receptors_, found in the _basal layer of the epidermis_. They are very aggressive. Pathologic nodal staging (neck dissection) has been associated with better survival, as 23% of patients with no clinical evidence of nodal disease were found to have positive nodes on neck dissection.
109
109 What is the relationship between Merkel cell polyoma virus (MCV) and Merkel cell carcinoma (MCC)?
About **80%** of Merkel cell carcinoma tumors have cells that exhibit MCV infection. MCV infection is widespread among humans, but it is thought to be an important factor in most MCCs.
110
110 What immunohistochemical stains are used for MCC?
1. Cytokeratin 20 (CK20) 2. Chromogranin 3. Cam5.2
111
111 A patient has a rapidly enlarging 6-cm cystic mass of the scalp. Excisional biopsy shows deep dermal and subcutaneous involvement, which histologically shows evidence of a squamous-lined cyst with extensive trichilemmal keratinization. What is the most likely diagnosis?
Proliferating trichilemmal cyst
112
112 What is the recurrence rate of microcystic adnexal tumors treated with wide local excision compared with those treated with Mohs surgery?
Wide local excision 60%, Mohs surgery 12%
113
113 A patient presents with an 8-mm lesion on the upper lateral eyelid. Biopsy shows neoplastic cells with sebaceous differentiation and cytoplasmic vacuolization. What is the preferred treatment?
Sebaceous carcinoma is an aggressive tumor with a proclivity for metastasis. Mohs surgical resection is associated with lower local and distant recurrence rates.
114
114 What are syringomata?
Syringomata are **benign sweat gland tumors** that commonly occur in multiples. They are more common in **women** and occur predominantly on the **face** at the eyelids, upper cheeks, and neck.
115
115 What is a pilomatrixoma?
**Benign appendageal tumors** that commonly affect the head and neck and contain a differentiation toward hair cells; rarely associated with carcinoma
116
116 What is the typical clinical presentation of a pilomatrixoma?
Single, firm, skin-colored or slightly bluish nodule occurring on the face, neck, and shoulders
117
117 What are epidermoid cysts?
Benign cutaneous cysts with epithelial lining that produce keratinized cellular debris. They usually occur after puberty and may rupture, drain, or become infected.
118
118 Which defects require immediate management?
* **Periocular defects** require early treatment to prevent ocular damage either with reconstruction or temporary eye closure. * **Perioral defects** with oral contamination should be reconstructed early to minimize oral contamination. * **Alar defects** should be reconstructed early to prevent tissue contraction.
119
119 What is the appropriate management of a 1-cm skin only central cheek defect?
Primary closure
120
120 What is the appropriate management of a 2- to 4- cm skin only central cheek defect?
Local flap
121
121 What is the appropriate management of a \> 4 cm skin-only central cheek defect?
Facial or cervicofacial rotation flap
122
122 What is the appropriate closure of a skin only defect of less than half the lip (orbicularis intact)?
Primary closure
123
123 What is the appropriate closure of a full thickness defect of half to two-thirds of the lip (commissure intact)?
Abbe-Estlander flap * Height of flap = height of defect * Width of flap = 1/2 width of defect
124
124 What is the appropriate closure of a full-thickness defect of one-half to two-thirds of the lip involving the commissure?
Karapandzic flap: modified the Gillies fan falp, bilateral advancement (melolabial creases are lateral extent), good for lower lip but can also be used for upper lip. Pros: excelelnt oral competence, can recurit cheek tissue Cons: unsightly circumoral scar, risk of microstomia, blunting of oral commissure, tedious dissection of neurovascular budle
125
125 What is the appropriate closure of a full thickness defect involving **greater than two-thirds of the lip**?
**Radial forearm free flap with _palmaris tendon_** or **anterior lateral thigh and _fascia lata_ flap**
126
126 What is the vascular supply for the paramedian forehead flap used in nasal reconstruction?
Supratrochlear artery and vein
127
127 What components of the nose must be considered during reconstruction?
Skin, cartilage, bone, and mucosal lining. Failure to reconstruct each of these elements will lead to poor cosmetic and functional results.
128
128 What is the aesthetic subunit principle of nasal reconstruction?
The nose is made up of **nine** subunits: 1. Dorsum 2. Tip 3. Columella 4. Lateral sidewalls x2 5. Ala x2 6. Soft tissue triangles x2 The best cosmetic result can be achieved when these are reconstructed separately, and **when greater than half of a subunit is resected, resection of the remainder of the subunit is desirable for cosmesis.**
129
129 What local flap is most commonly used for **nasal sidewall defects** when primary closure is not achievable?
**Bilobed flap** Transposition flap that recruits lax tissue (2/2 flap) from a nearby site that allows 1/1 flap to effect closure of the defect Primary flap should be slightly smaller than the defect, 2/2 falp should be 0.5-0.75 the width of the 1/1 flap (except on nasal tip where defect:primary flap = 1:1)
130
130 What is the general reconstructive ladder for full thickness lower eyelid defects?
* \< 30%: Primary closure, with or without lateral cantholysis, for larger defects * 30 to 50%: Semicircular flap with or without periosteum * \>50%: Tarsoconjunctival flap with flap or graft closure of the skin
131
131 What is a Tenzel flap?
Periorbital semicircular advancement flap for eyelid reconstruction
132
132 What is a Hughes flap?
A pedicled tarsoconjunctival flap used in reconstruction of large (\> 50 to 60%) full-thickness eyelid defects
133
133 What are limiting factors in using split-thickness skin grafts in **scalp** reconstruction?
* They require a **vascular bed**; if periosteum is absent, must drill to bleeding bone or rotate vascular tissue (periosteum, temporalis) into defect * Poor color, texture, thickness, and hair match * If postoperative radiation is required, a split-thickness skin graft on bone will very likely undergo necrosis.
134
134 What is the flap of choice for **large** (\> 100 cm2) scalp defects
**Latissimus dorsi myocutaneous free flap** with **split-thickness skin graft**