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NUR 105 Week 6: Evaluation and
Management of Dermatologic
Disorders Latest updated exam with
100% accuracy(EVERYTHING YOU
NEED TO PASS)
Objectives:
a. Acne, viral skin eruptions
b. Urticaria, pigmentation disorders
c. Alopecia
d. Candidiasis
e. Burns
f. Herpes Simplex Virus, Herpes Zoster
g. Psoriasis
h. Cellulitis/MRSA
i. Eczema/Atopic Dermatitis
j. Skin Cancers
k. Systemic Lupus erythematosus
l. Bites and Stings
Chapter 177: Screening for Skin Cancers
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Epidemiology and Risk
Factors Basal Cell
Carcinomas
- Basal cell carcinomas (BCCs) are the most common malignancy
in humans. They are distinctly sun related, with the majority
occurring on the head and neck, especially the nose and cheeks.
Recently an increase in frequency has been seen on the male
torso and on the legs of women. Other etiologic factors include a
genetically transmitted autosomal dominant disorder—the basal
cell nevus syndrome—in which multiple basal cell carcinomas
occur in relatively young persons in association with palmar pits,
bone cysts, and frontal bossing. Previously identified BCC is also a
risk factor. Once a single basal cell carcinoma has developed, the
chance that a second one will develop ranges from 36% to 50%.
This observation forms the basis of annual follow-up
examinations after basal cell carcinoma has been detected.
Squamous Cell Carcinomas
- Most squamous cell carcinomas develop from the precursor
lesion—actinic keratosis. Two thirds of these cancers occur on sun-
exposed surfaces, with risk proportional to total accumulated sun
exposure. Other precipitants include arsenic ingestion, radiation-
induced scarring, and thermal burns. Those lesions arising in sun-
damaged skin usually behave in a less biologically aggressive
fashion than do those that occur on non–sun-exposed or mucosal
surfaces and are less likely to metastasize Melanoma
- Melanoma, although far less common than are basal cell
carcinoma and squamous cell carcinoma, accounts for more than
75% of skin cancer deaths. The incidence has been increasing
rapidly during the last few decades and currently exceeds that of
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Hodgkin disease, leukemia, pancreatic cancer, carcinoma of the
thyroid, and carcinoma of the pharynx and larynx. The sex ratio
for melanoma in the United
States is approximately 1:1 with a modest male predominance. A
second primary melanoma develops in up to 10% of nonfamilial
patients; 10% have affected relatives Risk Factors and Precursors for
Melanoma
- Because of the rapid rise in melanoma incidence, attention has
focused on melanoma risk factors and precursors. Persons with
fair skin who tan poorly and burn easily are at greatest risk,
especially those with a history of episodic, intense sun exposure.
Blacks, Asians, and dark-skinned Whites have a much lower risk.
- Precursor lesions include congenital nevi and dysplastic nevi (i.e.,
clinically atypical moles). Although congenital nevi occur in
approximately 1% of all newborns, fortunately most of these are
small (≤1.5 cm in diameter). Melanoma risk has been most clearly
associated with large (>20 cm) nevi. Giant hairy nevus (Fig. 177-1)
is a form of congenital nevus associated with malignant
degeneration; the overall lifetime risk for malignancy is about
6%. Melanomas may arise in these lesions at any time throughout
life, but most often by age 10 years. Melanoma occasionally arises
in smaller pigmented congenital nevi, but the exact risk is
unknown.
- Dysplastic nevi occur in 5% to 10% of light-skinned Whites and
usually are recognizable in early adolescence. Lifetime risk for
melanoma is elevated severalfold in individuals with dysplastic
nevi. An inherited predisposition to dysplastic nevi may
contribute to the 8- to 12-fold increase in melanoma risk among
first-degree relatives of patients with melanoma. In patients with
dysplastic nevi and two or more first-degree relatives with
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cutaneous melanoma, the lifetime risk exceeds 50%. Patients
with a large number (>100) of benign-appearing nevi may also
be at increased risk.
Natural History of Skin Cancers and
Effectiveness of Therapy Basal Cell Carcinoma
- Rarely metastasize or cause death but locally invasive and
disfiguring
- Several effective forms of therapy exist, all yielding a cure rate of
approximately 95%: surgical excision, radiation therapy,
electrodesiccation and curettage, and cryotherapy with liquid
nitrogen applied by special spray apparatus. Treatment of the
5% that recur presents a greater challenge. The cure rate of a
recurrent basal cell carcinoma is about 66% when the four
traditional modalities just listed are applied. A special form of
micrographic surgery, Mohs surgery, is used for difficult, recurrent,
or infiltrative basal cell carcinomas. In Mohs surgery, the excised
tissue is examined microscopically by frozen section to determine
whether the tumor has been completely removed. Additional
sections of skin are removed until all the borders are
histopathologically clear of tumor. With Mohs technique, cure
rates of recurrent tumors exceed 90%, and those for primary
tumors are better than 98%.
- The use of 5-fluorouracil (5-FU) and imiquimod topically has
been advocated by some physicians for the treatment of
superficial basal cell carcinoma. These agents may have some
role in patients with multiple superficial lesions in whom other
techniques cannot easily be employed
Squamous Cell Carcinomas
FOR MORE EXAMS
EMAIL:
EMAIL:
NUR 105 Week 6: Evaluation and
Management of Dermatologic
Disorders Latest updated exam with
100% accuracy(EVERYTHING YOU
NEED TO PASS)
Objectives:
a. Acne, viral skin eruptions
b. Urticaria, pigmentation disorders
c. Alopecia
d. Candidiasis
e. Burns
f. Herpes Simplex Virus, Herpes Zoster
g. Psoriasis
h. Cellulitis/MRSA
i. Eczema/Atopic Dermatitis
j. Skin Cancers
k. Systemic Lupus erythematosus
l. Bites and Stings
Chapter 177: Screening for Skin Cancers
FOR MORE EXAMS
EMAIL:
,FOR MORE EXAMS
EMAIL:
Epidemiology and Risk
Factors Basal Cell
Carcinomas
- Basal cell carcinomas (BCCs) are the most common malignancy
in humans. They are distinctly sun related, with the majority
occurring on the head and neck, especially the nose and cheeks.
Recently an increase in frequency has been seen on the male
torso and on the legs of women. Other etiologic factors include a
genetically transmitted autosomal dominant disorder—the basal
cell nevus syndrome—in which multiple basal cell carcinomas
occur in relatively young persons in association with palmar pits,
bone cysts, and frontal bossing. Previously identified BCC is also a
risk factor. Once a single basal cell carcinoma has developed, the
chance that a second one will develop ranges from 36% to 50%.
This observation forms the basis of annual follow-up
examinations after basal cell carcinoma has been detected.
Squamous Cell Carcinomas
- Most squamous cell carcinomas develop from the precursor
lesion—actinic keratosis. Two thirds of these cancers occur on sun-
exposed surfaces, with risk proportional to total accumulated sun
exposure. Other precipitants include arsenic ingestion, radiation-
induced scarring, and thermal burns. Those lesions arising in sun-
damaged skin usually behave in a less biologically aggressive
fashion than do those that occur on non–sun-exposed or mucosal
surfaces and are less likely to metastasize Melanoma
- Melanoma, although far less common than are basal cell
carcinoma and squamous cell carcinoma, accounts for more than
75% of skin cancer deaths. The incidence has been increasing
rapidly during the last few decades and currently exceeds that of
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EMAIL:
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Hodgkin disease, leukemia, pancreatic cancer, carcinoma of the
thyroid, and carcinoma of the pharynx and larynx. The sex ratio
for melanoma in the United
States is approximately 1:1 with a modest male predominance. A
second primary melanoma develops in up to 10% of nonfamilial
patients; 10% have affected relatives Risk Factors and Precursors for
Melanoma
- Because of the rapid rise in melanoma incidence, attention has
focused on melanoma risk factors and precursors. Persons with
fair skin who tan poorly and burn easily are at greatest risk,
especially those with a history of episodic, intense sun exposure.
Blacks, Asians, and dark-skinned Whites have a much lower risk.
- Precursor lesions include congenital nevi and dysplastic nevi (i.e.,
clinically atypical moles). Although congenital nevi occur in
approximately 1% of all newborns, fortunately most of these are
small (≤1.5 cm in diameter). Melanoma risk has been most clearly
associated with large (>20 cm) nevi. Giant hairy nevus (Fig. 177-1)
is a form of congenital nevus associated with malignant
degeneration; the overall lifetime risk for malignancy is about
6%. Melanomas may arise in these lesions at any time throughout
life, but most often by age 10 years. Melanoma occasionally arises
in smaller pigmented congenital nevi, but the exact risk is
unknown.
- Dysplastic nevi occur in 5% to 10% of light-skinned Whites and
usually are recognizable in early adolescence. Lifetime risk for
melanoma is elevated severalfold in individuals with dysplastic
nevi. An inherited predisposition to dysplastic nevi may
contribute to the 8- to 12-fold increase in melanoma risk among
first-degree relatives of patients with melanoma. In patients with
dysplastic nevi and two or more first-degree relatives with
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cutaneous melanoma, the lifetime risk exceeds 50%. Patients
with a large number (>100) of benign-appearing nevi may also
be at increased risk.
Natural History of Skin Cancers and
Effectiveness of Therapy Basal Cell Carcinoma
- Rarely metastasize or cause death but locally invasive and
disfiguring
- Several effective forms of therapy exist, all yielding a cure rate of
approximately 95%: surgical excision, radiation therapy,
electrodesiccation and curettage, and cryotherapy with liquid
nitrogen applied by special spray apparatus. Treatment of the
5% that recur presents a greater challenge. The cure rate of a
recurrent basal cell carcinoma is about 66% when the four
traditional modalities just listed are applied. A special form of
micrographic surgery, Mohs surgery, is used for difficult, recurrent,
or infiltrative basal cell carcinomas. In Mohs surgery, the excised
tissue is examined microscopically by frozen section to determine
whether the tumor has been completely removed. Additional
sections of skin are removed until all the borders are
histopathologically clear of tumor. With Mohs technique, cure
rates of recurrent tumors exceed 90%, and those for primary
tumors are better than 98%.
- The use of 5-fluorouracil (5-FU) and imiquimod topically has
been advocated by some physicians for the treatment of
superficial basal cell carcinoma. These agents may have some
role in patients with multiple superficial lesions in whom other
techniques cannot easily be employed
Squamous Cell Carcinomas
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