Cutaneous Malignancies Flashcards
What are the layers of the epidermis from superficial to deep?
- Stratum corneum
- Stratum licidum
- Stratum granulosum
- Stratum spinosum
- Stratum basale (dermis is immediately deep to this)
Mneumonic: Come Lets Get Sun Burnt
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.
- Denotes where SCC and BCC of the face potentially demonstrate a more aggressive course.
Which skin cancer is most common on the lower lip
SCC
Risk factors associated with lymphatic metastasis of cutaneous SCC?
- Area greater than 20mm
- Recurrent tumors
- Site of prior radiation or scar
- Rapidly growing tumor
- Perineural invasion
- Poorly differentiated tumors or high grade
- Depth >5mm
- Lymphovascular invasion
- Immunosuppression
Metastasis from cutaneous head and neck SCC commonly occur in which lymphatics
- 75% in the parotid bed
- 40% in level II
Risk factors for cutaneous SCC of the head and neck
- UV radiation
- Light skin pigmentation
- Ionizing radiation
- Immunosuppression
- Exposure to coal tar, asphalt, arsenic consumption
- Xeroderma pigmentosa, basal cell nevus syndrome
- Tendency to burn or freckle
- Male sex
Fitzpatrick scale
Classification of the color of skin and associated with decreasing risk of cutaneous malignancy
Type 1: pale white, blond or red hair, blue eyes, always burns never tans, freckles
Type 2: white, fair, blond or red, blue, green or hazel eyes, tans minimally, often burns
Type 3: fair skin, any hair and eye color, tans evenly, sometimes burns
Type 4: Mediterranean skin, rarely burns, tans easily
Type 5: dark brown skin, rarely burns, tans easily
Type 6: dark brown to black skin, never burns, tans very easily
Actinic keratosis
Also called a solar keratosis is a rough patch on the skin caused by years of sun exposure. Immunosuppressed individuals can also develop these. Fewer than 1/1000 will go on to become SCC but 60% of SCC can be traced back to an AK
Marjolin ulcer
A term used to describe an ulcerative SCC at the site of prior trauma, inflammation or scarring such as radiation or a burn
What % of nonmelanoa cutaneous malignancies are made up of SCC
20%
What pathologic finding in SCC is associated with the highest recurrence rate and regional metastasis?
Perineural invasion. This is associated with metastasis in 47% of patients.
Bowen disease
An intraepidermal SCC that manifests as enlarging, well demarcated erythematous plaque with surface crusting. Histologically it resembles SCC with atypical keratinocytes replacing epidermis. More common in women in the 6th and 7th decades of life. Can appear anywhere but more common in lower legs. Risks include sun exposure, arsenic, immunosuppression, viral infection. Tx with cryotherapy, curettage, excision, laser, PDT, 5-FU
What type of skin cancer is known for rapid progression of a swelling, dome shaped lesion that eventually resolves by sloughing off and scarring. It can have a central crater containing keratinous debris.
Keratoacanthoma
Symptoms to be elicited in an HPI for a newly diagnosed cutaneous SCC
Symptoms of advanced disease: numbness, pain, weakness, other perineural symptoms; weight loss, bone pain, shortness of breath, rapid growth, bleeding, fixation, neck mass to suggest locally advanced disease
What features of cutaneous SCC merit radiologic workup?
- Locally advanced disease (>2cm, fixation, numbness, perineural or lymphovascular invasion)
- Regionally advanced disease (palpable lymphadenopathy)
- Distant metastasis risk
- High risk patients (recurrent lesions, immunosuppression, history of radiation)
What is the most appropriate biopsy technique for deep ulcerated lesions of the skin of the head and neck?
Punch 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.
T staging of head and neck nonmelanoma skin cancer
T1: smaller or equal to 2cm in greatest dimension
T2: 2-4cm or 2+ high risk features (>2mm invasion, clark level >IV, perineural invasion, primary site of the ear, primary site of non hair bearing lip, poorly or undifferentiated tumor)
T3: 4+ with minor bone erosion or perineural invasion
T4: gross cortical bone/marrow, skull base invasion
What locations of the head and neck are more likely to exhibit recurrence of cutaneous SCC
H zone due to these sites being the location of embryologic fusion affording tumor planes that provide avenues for spread.
What are appropriate margins for low risk cutaneous SCC?
4-6mm
Imiquimod
A local immune response modifier that induces activity or interferon alpha and other cytokines. Commonly used as a cream (brand name Aldara)
When is Mohs surgery indicated for cutaneous SCC of the head and neck?
Anatomically or aesthetically sensitive areas, where wide margins are not achievable (periorbital, nasal, periauricular, auricular, oral) or positive margins after WLE and potential extension into an area fulfilling the first criteria
When is radiation indicated for cutaneous SCC?
- Nonoperative candidates
- Positive margins or incomplete excision
- Solitary node >3cm or with extracapsular extension
- Multiple positive nodes
- Multiple recurrent disease despite appropriate treatment
- Perineural invasion
- T4 disease
Appropriate treatment of keratoacanthoma?
WLE can also use intralesional methotrexate and 5-FU for nonoperative cases
What proportion of BCC occur on the head and neck?
4 of 5 cutaneous BCC
Is upper lip cancer more common in men or women?
Women - 21% of lip cancers on the upper lip vs 3% of lip cancer in men
What % of cutaneous malignancies occur on the lower lip?
90%
Is basal cell carcinoma more likely on the upper lip or lower lip?
Upper lip (13% vs 1% of lower lip cancers)
What is the significance of BCC found in the folds of the face?
More likely recurrence and higher risk of spread due to embryonic fusion plates. Need close follow up.
Likelihood of regional nodal metastasis in BCC?
Rare. Occurs in less than 0.5% of patients
What is the mechanism by which UV B light damages skin?
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 corresponding TT is added to the growing strand.
Risk factors for BCC
Sun exposure, lightly pigmented skin, blue or green eyes, genetic conditions, tanning beds, arsenic, prior trauma, ionizing radiation, immunosuppression
High risk features for staging BCC
- Poor differentiation
- Perineural spread
- Origination of the ear or hair bearing lip
- Depth >2mm
- Clark level IV or V invasion
Clark levels
Clark levels of skin cancer. In Clark Level I, the cancer is in the epidermis only. In Clark Level II, the cancer has begun to spread into the papillary dermis (upper layer of the dermis). In Clark Level III, the cancer has spread through the papillary dermis into the papillary-reticular dermal interface but not into the reticular dermis (lower layer of the dermis). In Clark Level IV, the cancer has spread into the reticular dermis. In Clark Level V, the cancer has spread into the subcutaneous tissue.
What % of nonmelanocytic cutaneous neoplasms are BCC?
80%
Common types of BCC
There are 26 subtypes. The most common -
- Nodular: most common form, described as pearly with rolled borders and occasional central ulceration and peripheral telangectasias
- Morpheaform: (or sclerosis or fibrosing), irregular borders on yellow plaques, most aggressive type, high recurrence and worse prognosis
- Fibroepithelial: often a pink papule on the trunk
- Superficial: most common type on the trunk, irregularly shaped, waxy
- Other: commonly described as pigmented or micronodular
What % of BCC are nodular type?
56-78%
What subtype of BCC has the youngest average age at initial diagnosis?
Superficial
What aspect of morpheaform or sclerosing BCC type make them more aggressive?
They secrete collagenases enabling movement between anatomic subsites
What subtype of BCC is more common in Asian and African patients compared to Caucasians?
Pigmented BCC
Clinical constellation of basal cell nevus syndrome
Aka Gorlin syndrome - patients diagnosed at an early age with multifocal BCC, odontogenic keratocytes, bifid ribs, scoliosis, developmental delay and frontal bossing
Features associated with arsenic exposure
Truncal BCC
Keratoses of the palms and soles
Nail changes (Mees lines)
What type of biopsy should be performed for a suspected BCC?
Shave biopsy. When lesions are pigmented a punch biopsy should be performed as assess the depth of the lesion
When is imaging required for BCC?
Rarely. Done in large tumors, suspicion of invasion of deeper structures, symptoms of perineural invasion, palpable lymphadenopathy
When can cryotherapy be considered for management of BCC?
Small <1cm nonaggressive tumors
Advantages of Mogs surgery over simple excision?
Maximal preservation of normal tissue. Optimization of functional/cosmetic outcomes, assessment and clearing of entire margin, lower recurrence rates, immediate reconstruction (usually)
Nonsurgical management options for BCC
- Radiation therapy
- PDT
- Immunotherapy
- Chemotherapy
- Vismodegib : an agent that targets the hedgehog signaling pathway
In patients with cutaneous BCC when should neck dissection be considered?
Only in instances when there is clinical evidence of nodal metastasis
Why is best to defer reconstruction in morpheaform type of BCC
Classically exhibits subdermal spread resulting in more common recurrence than other variants
What % of mucosal melanomas present in the head and neck?
5%
Most common site of head and neck mucosal melanoma?
Nasal cavity
Incidence of lymphatic spread in malignant melanoma
Depends on subtype, depth and location
- < .75mm: <5%
- 0.75-4mm: 15-20%
- 4.0mm: 34%
- Incidence increases with ulceration, nodular type, Clark level IV or V and elevated mitotic rate
Where do 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
Metastatic rate of desmoplastic melanoma?
0-2.2% of cases of pure desmoplastic melanoma. It is more in mixed desmoplastic cases
How has melanoma changes in the US in the last 30 years?
It has seen a 3 fold increase in Caucasian population and been stable in black population
Risk factors for cutaneous mealnoma?
Family history, light skin, tendence to burn, red hair, DNA repair defects, sun exposure, equatorial residence, tanning bed use, immunosuppresion, >100 melanocytic nevi, more than 5 atypical melanocytic nevi, multiple solar lentigines, personal history of melanoma
What familial AD disorder greatly increases risk of melanoma?
Atypical mole syndrome
Common subtypes of cutaneous melanoma?
- Superficial spreading (57%)
- Nodular melanoma (21%) - most aggressive subtype
- Lentigo maligna (9%) - the least aggressive with a long radial growth phase
- Acral lentiginous (4%) - found on the soles of feet and palms of hands
- Unclassifiable (4%)
- Other (5%)
What sizes of congenital nevus have an increased risk of developing into melanoma?
Giant congenital nevus 2cm or larger
What differentiates lentigo maligna and lentigo maligna melanoma?
Lentigo maligna melanoma has invasion into the dermis
Most common genetic aberrations found in melanoma?
- Chronic sun damaged skin: KIT>KIT+NRAS=BRAF=NRAS
- Nonchronic sun damaged skin: BRAF»_space; NRAS
- Mucosal: KIT»_space; NRAS
ABCDEs of melanoma
Asymmetry Border irregularity Color variability Diameter greater than 6mm Evolving over time
What clinical evaluation should patients with newly diagnosed melanoma receive?
Full body skin exam
When should imaging be performed in malignant melanoma?
Extensive primary (fixation, perineural spread)
Abnormal or equivocal adenopathy
Stage III disease +
Specific signs to suggest metastatic spread
Most ideal method to obtain a biopsy of a lesion suspicious for mealnoma?
Narrow margin excisional biopsy with adequate depth to determine breslow depth
Histologic markers commonly used to identify melanoma
- HMB-45
- S-100 protein
- MART-1
Potential sites for occult primaries in patients with metastatic melanoma of the head and neck?
Ocular, mucosal, external auditory canal, hair bearing areas, tumor regression
T staging of cutaneous melanoma
T1a: thickness <0.88mm without ulceration
T1b: thickness0.8-1mm with or without ulceration
T2: thickness >1-2mm
T3: thickness >2-4mm
T4: thickness >4mm
a: without ulceration
b: with ulceration
M staging of cutaneous melanoma
M1a: metastasis to the dermis, soft tissue, nonregional lymph node
M1b: metastasis to the lung
M1c: metastasis to other visceral organs
(0) : LDH not elevated
(1) : LDH elevated
N staging for cutaneous melanoma
N1: one node
N2: 2-3 nodes
N3: 4+ nodes
a: occult
b: clinically detected
c: presence of in transit, satellite and or microsatellite metastasis
What is the most common site of melanoma metastasis?
regional lymph nodes
Lifetime risk of developing a second primary melanoma?
4-8%
In localized melanoma what is the most important prognostic factor?
tumor thickness
Respective 5 year survival rates for melanoma patients with positive and negative sentinel lymph nodes?
56% vs 90%
5 year survival for patients with metastatic melanoma?
10-20%
What serum factor is an independent predictor of survival in stage IV metastatic melanoma?
LDH
Treatment of choice for superficial thickness melanomas (1mm)
WLE with 1cm margins
When should SLNB be considered in melanoma measuring 0.75-1.0mm thickness?
Tumors with ulceration or one or more mitosis/mm2
Treatment of choice for intermediate thickness and deep melanomas (1-4+mm)
WLE with 2cm margins and SLNB
Which chemotherapeutic agent is approved for treatment of stage IV melanoma?
Dacarbazine
What adjuvant therapy is approved for use after surgery for stage III melanoma?
Interferon alpha2b
What is the recommended treatment for Spitz nevus?
Complete excision
Contraindications to methylene blue die injection
Previous hypersensitivity
Pregnancy
Concurrent use of SSRIs
Glucose 6 phosphate dehydrogenase deficiency
Most common complications associated with Mohs surgery?
Complications are rare. Hematoma and graft necrosis are most common.
Merkel cell carcinoma
A neuroendocrine tumor. Arises from Merkel cells which are specialized touch receptors found in the basal layer of the epidermis. Very aggressive. About 80% of tumors have cells that exhibit merkel cell polyoma virus
What immunohistochemical stains are used for Merkel cell carcinoma?
Cytokeratin 20 (CK20), chromogranin, Cam5.2
Syringomata
Benign sweat gland tumors that commonly occur in multiples. More common in women and occur predominantly on the face at the eyelids, upper cheeks and neck
Pilomatrixoma
Benign appendageal tumors that commonly affect the head and neck and contain differentiation toward hair cells, rarely associated with carcinoma. Typically presents as a single firm, skin colored or slightly bluish nodule
What is the appropriate management of a 1cm skin only central cheek defect?
Primary closure
What is the appropriate management of a 2-4cm skin only central cheek defect?
Local flap
What is the appropriate management of a >4cm skin only central cheek defect?
Facial or cervicofacial rotation flap
What is the appropriate closure of a skin only defect of less than half of the lip (orbicularis oris intact)
Primary closure
What is the appropriate closure of a full thickness defect of half to two thirds of the lip (commissure intact)
Abbe-Estlander flap
What is the appropriate closure of a full thickness defect of half to two thirds of the lip involving the commissure?
Karapandzic flap
What is the appropriate closure of a full thickness defect involving greater than 2/3 of the lip?
Radial forearm free flap or ALT
What is the vascular supply for paramedian forehead flap
Supratrochlear artery and vein
What components of the nose must be considered during reconstruction?
Skin, cartilage, bone, mucosal lining. Failure to reconstruct each of these will lead to poor cosmetic and functional outcome
What is the aesthetic subunit principle of nasal reconstruction?
Reconstruct each of the 9 subunits separately. When greater than half of a subunit is resected, resection of the remainder of the subunit is desirable for cosmesis
What local flap is most commonly used for nasal sidewall defects when primary closure is not achievable?
Bilobed flap
General reconstruction ladder for full thickness lower eyelid defects?
<30% - primary closure with or without lateral cantholysis for larger defects
30-50%: semicircular flap with or without periosteum
>50%: transconjunctival flap with flap or graft closure of the skin
Tenzel flap
Periorbital semicircular advancement flap for eyelid reconstruction
Hughes flap
A pedicled tarsoconjunctival flap used in reconstruction of large >50-60% full thickness eyelid defects
Limiting factors in using split thickness skin grafts in scalp reconstruction
- Require a vascular bed; is periosteum is absent must drill to bleeding bone or rotate vascular tissue into defect
- Poor color, texture, thickness and hair match
- If postop radiation required a split thickness graft on bone will likely die
What is the flap of choice for large scalp defects?
Latissimus dorsi myocutaneous free flap with split thickness skin graft
