This preview shows page 1. Sign up to view the full content.
Unformatted text preview: iated with SCC is estimated to be approximately
Unlike BCCs, SCCs often arise in precursor lesions, such as actinic keratoses.20 Actinic keratoses, sometimes referred to as solar
keratoses, develop in chronically sun-damaged areas of the body.
These lesions are often multiple, are generally ill-deﬁned and irregular, and may range in size from about 1 mm to a few centimeters.
They have a scaly appearance and exhibit a wide variety of colors,
from dark brown to ﬂesh-pink. Biopsy may be necessary to rule out
the presence of a SCC. Although the rate at which actinic keratosis
undergoes malignant transformation to SCC is less than 0.1% per
year,21 lesions should nevertheless be treated to reduce the chances
of progression. Treatment options include cryotherapy, curettage,
and topical therapy. Surgical excision of actinic keratoses is rarely
necessary but may be indicated if there is a high level of suspicion for
Intraepithelial SCC (carcinoma in situ), also known as Bowen
disease, is thought to be the next step in the progression from actinic keratosis to invasive SCC.The lesions are typically located on sunexposed areas of the head, neck, trunk, or legs; when they are located on the genitalia, the condition is referred to as erythroplasia of
Queyrat. Lesions that develop on non–sun-exposed areas may be associated with internal malignancy.22 Intraepithelial SCCs typically
appear as erythematous, slightly keratotic plaques and are usually
larger than the lesions of actinic keratosis. They should be excised
with a 5 mm to 1 cm margin.
As noted (see above), SCCs are most often associated with sun
exposure, though they may also be seen in patients with old scars,
radiation-damaged skin [see Figure 2a], or chronic open wounds.23
Chronic inﬂammation and irritation appear to be the common denominators. SCC that arises in a burn scar or a chronic, open
wound overlying osteomyelitis is often referred to as a Marjolin ulcer. SCCs that develop from Marjolin ulcers are characterized by
aggressive regrowth after incomplete biopsy.
SCCs typically appear as reddish-brown, pink, or ﬂesh-colored
keratotic papules [see Figure 2b]; ulceration is sometimes, though not
always, present. If there is extensive hyperkeratosis, a cutaneous
“horn” may be evident.18 Symptoms that may suggest malignant
transformation of actinic keratosis into SCC include pain, erythema,
ulceration, and induration. Histologically, SCCs are characterized
by nests of atypical keratinocytes that have invaded into the dermis,
which may be either well or poorly differentiated.
Once the diagnosis of SCC is suspected, careful attention should
be paid to the draining nodal basins with the aim of detecting possible lymph node metastasis. The risk of such metastasis is between
2% and 4% overall but is somewhat higher in patients with relatively large and poorly differentiated lesions and in patients with lesions
located on the scalp, the nose, the ears, the lips, or the extremities.
View Full Document
This note was uploaded on 03/21/2011 for the course ONC 01 taught by Professor Dzodic during the Spring '11 term at Multimedia University, Cyberjaya.
- Spring '11
- The Land