Cutaneous SCC Flashcards
What are the layers of the epidermis from superficial to deep?
● Stratum corneum (cornified layer) ● Stratum granulosum (granular layer) ● Stratum spinosum (spinous layer) ● Stratum germinativum (basal layer) The dermis is immediately deep to this.
Name the four cell types of the epidermis.
● Keratinocytes (80%)
● Merkel cells (mechanoreceptors)
● Langerhans cells (antigen processing and presenting cells
● Melanocytes (pigmented dendritic cells)
What is the “H-zone” of the head and neck?
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.
Which skin cancer type is most common on the
lower lip?
Squamous cell carcinoma
What risk factors are associated with lymphatic metastasis of cutaneous squamous cell carcinoma?
● Area > 20 mm (less in the H-zone) ● Recurrent tumors ● Site of prior radiation or scar ● Rapidly growing tumor ● Perineural invasion ● Poorly differentiated tumors, high-grade tumors ● Depth > 5 mm or subcutaneous fat ● Lymphovascular invasion ● Immunosuppression
Metastasis from cutaneous head and neck squamous cell carcinoma most commonly occurs in which lymphatics?
About 75% of cutaneous lymphatic metastases occur in the
parotid bed; 40% occur in level II.
What are risk factors for cutaneous squamous cell
carcinoma of the head and neck?
● 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
Describe the Fitzpatrick scale.
Classification schema for the color of skin. Associated with decreasing risk of cutaneous malignancy:
● Type I: Pale white, blond, or red hair; blue eyes; always
burns, never tans; freckles
● Type II: White, fair, blond or red hair; blue, green, or hazel
eyes; tans minimally, often burns
● Type III: Fair skin; any hair and eye color; tans evenly,
sometimes burns.
● Type IV: Mediterranean skin, rarely burns, tans easily
● Type V: Dark brown skin, rarely burns, tans easily
● Type VI: Dark brown to black, never burns, tans very easily
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?
Sun exposure is the most important risk factor, but immune suppression is also important (immunsuppressed 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.
What is Marjolin ulcer?
Marjolin ulcer is a term used to describe an ulcerative
squamous cell carcinoma at the site of prior trauma,
inflammation, or scarring such as radiation or a burn.
What percentage of nonmelanoma cutaneous
malignancies are made up of squamous cell
carcinoma?
20%
Which pathologic finding in squamous cell carcinoma is associated with the highest recurrence rate and regional metastasis?
Perineural invasion. This is associated with metastasis in
47% of patients.
How many solar keratoses eventually undergo
malignant transformation?
Fewer than 1 in 1,000 solar keratoses will become
squamous cell carcinoma.
What percentage of squamous cell carcinomas can
be traced to actinic keratosis?
60%
Describe the clinical and pathological characteristics of Bowen disease.
Bowen disease is an intraepidermal squamous cell carcinoma
that manifests as an enlarging, well-demarcated erythema-
tous plaque with surface crusting. Histologically, it resembles
squamous cell carcinoma with atypical keratinocytes replac-
ing 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.
What type of skin cancer is known for rapid
progression of a swelling, dome-shaped lesion that
eventually resolves by sloughing off and scarring?
Keratoacanthoma
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?
Keratoacanthoma
Describe the typical manifestation of a keratoacanthoma.
Keratoacanthomas are rapidly growing lesions that may
then slowly spontaneously involute after a plateau phase.
Describe the typical manifestation of cutaneous
squamous cell carcinoma.
Cutaneous squamous cell carcinoma can present in a number
of ways: A thick, scaly patch, an ulcerated patch with rolled
borders, a nodular lesion, or scale with pigmentation
What symptoms should be elicited in an history of
present illness for a patient with newly diagnosed
cutaneous squamous cell carcinoma?
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
What features of cutaneous squamous cell carcinoma merit radiologic workup?
● Locally advanced disease: Fixation, numbness, weakness,
pain or trismus, extensive lesions (> 2 cm), or perineural
or lymphovascular invasion
● Regionally advanced disease: Palpable lymphadenopathy,
intransit metastasis
● Distant metastasis risk: Axillary adenopathy, bone pain, shortness of breath, unexplained weight loss, unex-
plained neurologic symptoms
● High-risk patients: Recurrent lesions, immunosuppres-
sion, history of radiation
What is the most appropriate biopsy technique for
deep ulcerated lesions of the skin of the head and
neck?
● 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.
What features of head and neck nonmelanoma
skin cancer are associated with American Joint
Committee on Cancer (AJCC) T2 tumors?
Greater than 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-hairbearing lip ● Poorly or undifferentiated tumor Note: Excludes cutaneous squamous cell carcinoma of the eyelid
What features of head and neck nonmelanoma
skin cancer are associated with T3 and T4 tumors
(AJCC seventh edition)?
● T3: Invasion of the maxilla, mandible, orbit, or temporal
bone
● T4: Perineural invasion of the skull base
