Skin Lesions Flashcards
How are pigmented lesions evaluated?
ABCDE: asymmetry, Border irregularity, colors variable, diameter of more than 6 mm, erythema.
Differential diagnosis for skin lesions?
Benign lesions – keratoses or pigmented lesions. Malignant lesions – BCC, SCC, adnexal tumors, cutaneous melanoma
Name the types of keratoses
“SACKS” Seborrheic keratoses, actinic keratoses, cutaneous horns, keratocanthomas
Describe some characteristics of seborrheic keratoses?
Common benign lesions, trunks of elderly patients, multiple rounds tan to black well demarcated plaque like, biopsy not necessary
Describe general characteristics of actinic keratoses
Common, sun exposed areas, 20% progress to squamous cell carcinoma within one year if not treated, raised, red, gritty, scaley
Treatment for actinic keratoses?
Removal by excision, topical 5– fluorouracil, cryotherapy and electrodesiccation.
Describe characteristics of Keratoacanthomas
Solitary usually benign, sun exposed skin and adults older than 40, rapidly enlarge over 6–8 weeks, painless firm well circumscribed and raised nodules with shiny unpigmented rim and scaly cratered Center. Should excise.
Cutaneous horns
Hard scaly conical projections up to several centimeters in length. Most common on face or scalp of elderly, 25% arise from premalignant bases of actinic keratoses and bowens disease, 15% from SCC
Bowen’s disease
SCC in situ
- ill-defined, scaly red plaques
- head and neck
- biopsy necessary to differentiate from superficial basal cell carcinoma or actinic keratosis
Rx for bowen’s disease
Treat with superficial removal curettage, electrodesiccation, cryotherapy, shave excision
What are the four types of nevi?
Melanocytic, compound, junctional, architectural disorder
Melanocytic Nevus
- benign proliferation of melanocytes in the dermis
- no need for excision unless suspicious
Compound melanocytic nevus
- Melanocytes at dermoepidermal junction and dermis
- raised, flesh colored to Brown
Junctional melanocytic nevus
- melanocytes at the dermoepidermal junction
- m/c in children
- transforms to compound nevus by adulthood
- small, flat, brown, regular borders with no distortion of surrounding skin
Nevus with architectural disorder
- acquired lesion
- appeared similar to malignant melanoma, large-size 5 to 10 mm
- often seen in familial disorders
Basal Cell Carcinoma
- incidence?
- Cause?
- Where on body?
- m/c skin malignancy, 800,000 cases per year
- Chronic UV A or B exposure, immunosupppresion
- sun exposed parts of body
- pigmented or black
Types of BCC
Superficial BCC
Nodular BCC
Morpheaform or sclerosing BCC
Superficial BCC
least aggressive
red scaly patch grows to peripheral extension
usually on trunk/extremities
Nodular BCC
- M/C
- more aggressive
- pink, elevated, firm and shiny with rolled borders and pearly appearance, usually overlying telangietasia
Morpheaform or sclerosing BCC
- more aggressive
- yellowish or pale plaquelike lesion
- ill defined borders blend into surrounding skin
Treatment for BCC?
- surgical excision with negative histologic margins (2-4 mm normal appearing skin)
- small well defined lesions with radiation or cryotherapy but rate of recurrence higher and cosmetic results poorer
What is the cure rate for BCC?
with treatment, >90%
Incidence of SCC?
2nd m/c skin malignancy
200,000 cases/year
Risk factors for SCC
sun-exposure, fair skin, hydrocarbons and arsenic, immunosuppression, chronic inflammation
Appearance of SCC?
Hyperkeratotic, flesh colored, raised, may have ulceration or surrounding erythema
Rx for SCC?
Surgical excision with negative margins (2-4mm normal appearing skin)
What are adnexal tumors?
Tumors arising from skin appendages (hair follicles, eccrine, apocrine, and sebaceous glands, fibrous tissue and neural tissue)
-examples: pilomatricoma, merkel cell carcinoma, cylindroma
Rx adnexal tumors. Prognosis?
Surgical excision, depends on origin of tumor.
Incidence of cutaneous melanoma?
54,200/year, incidence increased significantly over last 40 years
5th m/c cause cancer in men
7th m/c cause cancer in women
Diagnosis of skin lesions?
Asymmetry Border irregularity Color variation Diameter > 6mm Evolution or elevation
Types of biopsies?
Excisional biopsy preferred. Punch biopsy acceptable for larger.
- Thickness of tumor most important prognostic indicator, full thickness biopsy.
- AVOID SHAVE BIOPSY
When should sentinel node biopsy be considered?
patients without clinical evidence of nodal involvement (palpable nodes) but with reasonable possibility of occult nodal involvement, absence of widely metastatic disease.
-intermediate thickness (1-4mm) most likely to benefit from SNB
Is SNB offered for lesions <1mm?
if lesion <6% risk of nodal metastasis so SNB not routinely offered. If other risk factors for mets including ulceration, regression, male gender, or axial location.
Prognosis for thick melanomas?
70% risk of occult systemic mets and 60-70% risk of occult nodal mets.
Indications for radical lymphadenectomy?
Standard treatment for all patients with REGIONAL NODAL METS (clinically palpable disease proven to be mets by FNA or excisional biopsy of palpable node or SNB+)
Indication for adjuvant therapy?
interferon alfa-2b improves survival in patients with high risk melanoma (>4mm thickness or nodal mets)
What determines risk of recurrence for melanoma?
Thickness and +/- nodal mets
Where will recurrence of melanoma occur?
Wide local excision site and regional nodal basin. Distant mets possible: nods, lung, liver, brain, bone, GIT
F/u for patients with thin melanoma?
node negative followed q6mo for 2-3 years, then annually 2-3 years
F/u for patients with intermediate or thick melanoma?
q3-6 months for 3 years, q4-12 months for 2 years, then annually
Which factors lead to a poor prognosis and melanoma?
Lesions > 0.75mm lesions on the back, arms, neck, and scalp; and female gender
Tumor stage Tis
Description and what are the surgical margins?
Tumor confined to epidermis.
Surgical margins 5 mm
T1 melanoma
Description and surgical margins?
Tumor depth < or = 1mm
Surgical margins 1 cm
T2 melanoma
Description and surgical margins?
Tumor depth of 1.01-2 mm
Surgical margins 1-2 cm
T3 melanoma
Description and surgical margins?
Tumor depth 2.01 - 4mm
Surgical margins 2 cm
T4 melanoma
Description and surgical margins?
Tumor depth > 4 mm
Surgical margins > 2 cm
