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Last Updated: December 11, 2006
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Synonyms and related keywords: basal cell carcinoma of the skin, BCC, basal cell Miscellaneous
epithelioma, rodent ulcer, squamous cell carcinoma, SCC, nodular basal cell
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carcinoma, noduloulcerative basal cell carcinoma, morpheaform basal cell carcinoma, Bibliography
sclerosing basal cell carcinoma, superficial basal cell carcinoma, basosquamous
carcinoma, basisquamous carcinoma, basal squamous cell carcinoma, skin BCC
Skin Cancer: Basal Cell
Carcinoma
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Section 1 of 10
Author Information Introduction Clinical Differentials Workup Treatment Follow-up Miscellaneous Pictures
Bibliography
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[Squamous Cell
Author: M Abraham Kuriakose, MD, DDS, FRCS, Chairman, Head
Carcinoma of the
and Neck Institute, Amrita Institute of Medical Sciences
Skin]
M Abraham Kuriakose, MD, DDS, FRCS, is a member of the following
medical societies: American Head and Neck Society, British
Association of Oral and Maxillofacial Surgeons, and Royal College of
Surgeons of England
Patient Education
Editor(s): Jaime R Garza, MD, DDS, FACS, Consulting Staff, Private Cancer and
Practice; Francisco Talavera, PharmD, PhD, Senior Pharmacy Editor, Tumors Center
eMedicine; Karen Hall Calhoun, MD, Chair, Professor, Department of
Otolaryngology-Head and Neck Surgery, University of Missouri;
Skin Cancer
Overview
Christopher L Slack, MD, Otolaryngology-Facial Plastic Surgery,
Private Practice, Associated Coastal ENT; Medical Director, Treasure
Skin Cancer
Coast Sleep Disorders; and Arlen D Meyers, MD, MBA, Professor,
Causes
Department of Otolaryngology-Head and Neck Surgery, University of
Colorado School of Medicine
Skin Cancer
Symptoms
Disclosure
Skin Cancer
Treatment
Skin Biopsy
Introduction
Skin Biopsy
Preparation
INTRODUCTION
Section 2 of 10
Author Information Introduction Clinical Differentials Workup Treatment Follow-up Miscellaneous Pictures
Bibliography
Background: Basal cell carcinoma (BCC) constitutes approximately
80% of all nonmelanoma skin cancers. The tumors most often appear in
individuals aged 40-60 years. BCC's predilection for the head and neck
is notable and is related to its primary etiology—solar exposure.
Approximately 75-86% of primary BCCs are found on the head or neck.
The most common location on the head is the nose, specifically the
nasal tip and alae. Australia has the highest incidence of basal cell
carcinoma in the world.
Sun exposure is the primary etiologic agent for the development of
BCC. Risk is related to skin type and the degree of exposure to sunlight,
particularly UV-B radiation. The tumors are more frequent in individuals
with fair complexions. Fitzpatrick skin-type scale, which ranges from
very fair (skin type I) to very dark (skin type VI), categorizes cutaneous
sensitivity to UV radiation. It is based on the individual's tendency to
burn and tan and is a good predictor of relative risk among whites. The
prevalence of BCC increases in areas of higher altitude and in areas of
lower latitude. The incidence of BCC is rising, partly because of
atmospheric changes and the increased popularity of sunbathing.
Pathophysiology: BCC primarily affects sun-exposed skin, particularly
the upper two thirds of the face.
Frequency:

In the US: For statistical purposes, BCC and squamous cell
carcinomas (SCCs) are grouped as nonmelanoma skin cancer.
Incidence of non-melanoma skin cancer varies depending on
geographic location. These cancers cause about 300 cases per
100,000 population in Texas and Arizona. The incidence is about
half that figure in New York and Maine.

Internationally: Australia has the highest incidence of BCC,
ranging from 650-1560 cases per 100,000 population.
Mortality/Morbidity: The estimated annual death rate from this tumor is
0.44 per 100,000 persons. Most of these deaths are due to SCC. BCC
rarely causes death. Morbidity is associated with uncontrolled advanced
disease.
Race: Whites of Celtic ancestry have the highest risk for BCC.
Incidence is low in blacks, Asians, and Hispanics.
Sex: BCC has a male predilection, with a 2:1 male-to-female ratio.
Age: Incidence peaks in persons aged 55-75 years.
CLINICAL
Section 3 of 10
Author Information Introduction Clinical Differentials Workup Treatment Follow-up Miscellaneous Pictures
Bibliography
History: BCC appears as insidious, painless, nonhealing ulcers or
nodules on the sun-exposed parts of the body. BCC has a particular
predilection for the upper two thirds of the face and is common among
white men who are elderly. Because of changing sun-exposing lifestyle
patterns among the sexes, the male sex predilection is gradually
decreasing. During the clinical evaluation, the patient's social and
occupational history of sun exposure, family history of skin cancer, and
geographic area of origin are determined to estimate the likelihood that
a second primary tumor will develop. Obtain a past history of treatment
of the index tumor or other skin tumors. In patients with recurrent
tumors, deeper invasion should be expected. Recurrence following
radiation therapy is often biologically more aggressive.
Physical: Physical examination should attempt to elicit the subtype of
BCC, extent of the tumor, and involvement of important cosmetic and
functional structures. Palpation should be used to attempt to estimate
the depth of invasion and fixation to the underlying structures. In
patients with recurrent or deeply infiltrative tumors, involvement of the
facial nerve or branches of the trigeminal nerve should be tested. Facial
nerve function can be monitored by comparing facial symmetry during
voluntary facial movements with that at rest. Sensory nerve function can
be tested and compared to the nonaffected side by means of light touch
and pinprick. Orbital invasion can cause diplopia, proptosis, and
ophthalmoplegia. Any limitation in ocular movements and/or diplopia
should be tested.
BCC seldom causes regional or distant metastasis, with the exception of
the metatypical basosquamous type. To evaluate for lymph node
metastasis, particular attention should be taken to examine the parotid
posterior auricular, suboccipital, and upper cervical groups of lymph
nodes. Four different clinicopathologic types of BCC exist, each with
distinct biologic behavior.

Undifferentiated BCC

Nodular or noduloulcerative BCC
o
o



More than 60% of BCCs belong to this subtype.
These lesions appear as well-circumscribed, domeshaped, pearly nodules with or without ulceration.
Superficial BCC
o
This BCC subtype appears as a red scaly patch that
resembles the chronic dermatitis predominantly seen in
the extremities.
o
These tumors spread superficially and can involve a large
surface area.
o
Although satellite islands appear multifocal on standard
histopathologic examination, 3-dimensional reconstruction
shows that they are interconnected.
Morpheaform or sclerosing BCC
o
This form accounts for 10% of lesions.
o
Lesions appear as flat or slightly depressed, fibrotic, and
firm.
o
The tumor has a deeply infiltrative character, which may
extend beyond the clinically obvious tumor. This feature
increases the recurrence potential of morpheaform or
sclerosing BCC.
Micronodular BCC
o
This type manifests as a plaquelike indurated lesion with
poorly demarcated contours.
o

Other BCCs
o
o
o

They have increase incidence of recurrence and an
aggressive behavior.
Aggressive-growth BCC
Infiltrative-growth BCC
Metatypical BCC
Differentiated BCCs
o Keratotic BCC
o Infundibulocystic BCC
o Follicular BCC
o Pleomorphic BCC
Causes: Incidence of BCC correlates with the amount of accumulated
sun exposure. Epidemiologic and molecular studies have confirmed that
the UV radiation (UVR) spectrum of sunlight, in synergy with genetic
susceptibility, is responsible for BCCs.


UV radiation
o
The UVR spectrum of sunlight is divided into 3 parts: long
wave UV-A (320-400 nm), intermediate wave UV-B (290320 nm), and shortwave UV-C (200-290 nm).
 UV-B and UV-C can modify unsaturated chemical
bonds of nucleic acids, which may lead to
mutations.
 UV-C does not penetrate the atmospheric ozone
layer; therefore, UV-B is the primary agent
responsible for most skin cancers.
 The UV-A spectrum is absorbed by melanin and,
through free-radical transfer, affects cellular
deoxyribonucleic acid (DNA).
o
Mutations caused by UVR typically include cytosine (C) to
thymine (T) or CC to TT translocation. This process can
cause activation of oncogenes or inactivation of tumor
suppressor genes, leading to tumor initiation and
progression.
Host factors
o
In addition to environmental factors, host factors play a
critical role in the pathogenesis of BCC. Host factors
include racial predilections, genetic syndromes,
predisposing syndromes, and immunologic factors.

o
Racial and ethnic factors
 White race with Celtic ancestry (eg, Irish, Scottish,
Welsh) has the highest predilection for BCC.
 Predilection is primarily related to the pigmentary
characteristics of the skin and sun sensitivity.
 Ability to tan is the most important protective factor.
 Light eye color; red, blonde, or light-brown hair
color; and freckling are strong predictors of BCC.
o
Genetic syndromes
 Xeroderma pigmentosa is a rare autosomal
recessive disorder characterized by hypersensitivity
to UVR. It causes defects in DNA repair and
synthesis, resulting in cutaneous cancers (eg, BCC,
SCC, melanoma).
 Nevoid basal cell syndrome is an autosomal
dominant disorder associated with multiple BCCs,
odontogenic keratocysts, calcification of falx
cerebri, and rib abnormalities.
 Epidermodysplastic verruciformis is an autosomal
recessive disorder characterized by the
development of BCC and SCC from warts.
Molecular alterations
o
Inappropriate activation of the hedgehog (HH) signaling
pathway is found in both sporadic and familial cases of
BCC. This results in loss-of-function mutations in tumorsuppressor protein patched homologue 1 (PTCH1) and
gain-of-function mutations in SHH, SMO, and GLI.
o
Mutations in TP53 are found in about 50% of sporadic
cases. Most show signature mutations that indicate
exposure to UV-B radiation.
DIFFERENTIALS
Section 4 of 10
Author Information Introduction Clinical Differentials Workup Treatment Follow-up Miscellaneous Pictures
Bibliography
[Squamous Cell Carcinoma of the Skin]
Other Problems to be Considered:
Eczema
Psoriasis
Actinic keratitis
WORKUP
Section 5 of 10
Author Information Introduction Clinical Differentials Workup Treatment Follow-up Miscellaneous Pictures Bibliography
Imaging Studies:

Perform diagnostic imaging studies for advanced tumors when there is question
of invasion or involvement of underlying soft tissue or bone.

CT scanning with bone windows is the imaging study of choice. As incidence of
nodal metastasis is very low, evaluation of the neck is not essential.

For early BCC, clinical examination suffices to determine extent of lesion.
Other Tests:

Photo documentation
Procedures:

Obtain a biopsy of the tumor to confirm the diagnosis and determine the
histologic subtypes. Complete an incision or punch biopsy prior to definitive
treatment.
o
Obtain the biopsy from the margins of the lesion to include both tumor and
normal tissue.
o
A shave biopsy may be difficult to interpret because of tangential
sectioning and should be avoided.
Histologic Findings: The basaloid appearance of the epithelial islands is the
pathognomonic feature of BCC. The cells mimic germinative epithelium and have an
increased nuclear cytoplasmic ratio. These cells show peripheral palisading, in which
they are arranged perpendicular to the basement membrane. The tumor has a
characteristic invasive pattern with the formation of large islands, cords, and teardrops.
Cells within the center of the epithelial islands have nondiscrete cytoplasmic borders
and mimic syncytium. The cells do not have prominent nucleoli and lack intercellular
bridges. The stomas show varying amounts of collagen deposition with abundant mucin.
Staging:



Primary tumor TX: Primary tumor cannot be assessed.
o
T0 - No evidence of primary tumor
o
T1 - Tumor 2 cm or less in greatest dimension
o
T2 - Tumor more than 2 cm but not more than 5 cm in greatest dimension
o
T3 - Tumor more than 5 cm in greatest dimension
o
T4 - Tumor invading deep extradermal structures
Regional lymph node NX: Regional lymph node cannot be assessed.
o
N0 - No regional lymph node metastasis
o
N1 - Regional lymph node metastasis
Distant metastasis MX: Presence of distant metastasis cannot be assessed.
o M0 - No distant metastasis
o M1 - Distant metastasis
TREATMENT
Section 6 of 10
Author Information Introduction Clinical Differentials Workup Treatment Follow-up Miscellaneous Pictures Bibliography
Medical Care: The treatment of BCC is surgical. Chemotherapy does not play a role in
the management of BCC. In patients with unresectable tumors, radiotherapy may be
attempted as palliative treatment. Radiotherapy may be considered as an adjuvant to
surgery in patients with advanced tumors or as a definitive treatment in selected
patients with early tumors.
Surgical Care: Curettage, cryotherapy, and laser ablation may be used to treat small
superficial BCC. Surgical excision with a margin of normal tissue is generally
recommended for all other lesions. This practice allows histologic examination of the
specimen for confirmation of the adequacy of excision. Surgery also provides a high
cure rate. Excise early tumors with a margin of normal tissue; the defect can be closed
primarily or with skin grafts or local flaps. Advanced-stage tumors require a
multidisciplinary approach, involving head and neck surgical oncologists, Mohs
micrographic surgeons, pathologists, reconstructive plastic surgeons, prosthodontists,
and anaplastologists. Neurosurgeons, ophthalmic surgeons, and radiotherapists may be
included in selected patients.

The principal aim of surgical treatment is to obtain complete excision of tumor
with uninvolved margins. Cosmetic and functional concerns are secondary. The
extent of surgical margin required depends on the histologic types. Although
tumor clearance can be achieved with a narrow margin in noduloulcerative BCC,
morpheaform BCC requires a wider margin. Expect deeper and/or wider
infiltration in tumors arising in the midface, patients with a previous history of
radiation, and patients with recurrent tumors. Smaller tumors can be excised in
the clinic under local anesthesia with or without sedation. Larger lesions or
lesions involving selected anatomic subsites (eg, eyelids) are best managed in
the operating room.

Two distinct surgical approaches are practiced in BCC excisions: en bloc
excision and Mohs micrographic surgery. In the first option, perform en bloc
surgical resection with the aim to remove tumor with a clear margin. After clearly
orienting the specimen, check margins by using frozen section. Histologic studies
have confirmed that the subclinical extension of disease varies from 1-6 mm.
Tumors larger than 2 cm have wider subclinical invasion than smaller lesions;
therefore, a tumor smaller than 2 cm requires a margin of only 4 mm to achieve
adequate clearance. Larger morpheaform BCC requires a resection margin of 12 cm. The incidence of recurrence following surgical excision is 30% for patients
with positive margin, 12% with close margin, and less than 5% for complete
excision.

In Mohs micrographic surgery, excise the tumor with close margins and process
specimens by using frozen section. This technique identifies the precise
anatomic location of the residual tumors, which then can be re-excised. By serial
frozen section examination and re-excision, this procedure allows complete
excision of tumor and limited removal of normal structures, thereby preserving
function and cosmoses without compromising the cure rate. Mohs micrographic
surgery is a labor-intensive procedure. Current indications of Mohs micrographic
surgery are recurrent tumors, tumors larger than 2-cm diameter, morpheaform
BCC, and tumors located at the high-risk periorbital and nasal region.

Depending on complexity of the procedure, the principle of reconstructive ladder
may be followed in reconstructing BCC surgical defects. This principle includes
allowing healing by means of secondary intention, primary closure, skin graft,
local flap, free flap, or prosthesis use. The reconstructive procedure can be
performed concurrent with surgery or as a secondary procedure after obtaining
final pathologic result.
Consultations: Although early BCC can be treated adequately by means of local
excision, advanced and recurrent tumors are best managed by a multidisciplinary
approach involving head and neck surgical oncologists, Mohs micrographic surgeons,
reconstructive plastic surgeons, pathologists, prosthetists, and radiation oncologists.
During the initial consultation, counsel the patient regarding the extent of resection, type
of reconstructive procedure, and attendant morbidity. Attach great importance to
adequately preparing the patient regarding the cosmetic and functional result of
treatment. During posttreatment follow-up, counsel the patient regarding sunlight
exposure and the risk of second primary skin tumors.
Diet: No dietary restrictions are indicated.
Activity: No restrictions in physical activities are indicated. To prevent second primary
skin tumors, counsel the patient to avoid lifestyles that risk excessive sunlight exposure.
FOLLOW-UP
Section 7 of 10
Author Information Introduction Clinical Differentials Workup Treatment Follow-up Miscellaneous Pictures Bibliography
Further Inpatient Care:

The reconstruction of the surgical defect may be performed concurrent with the
primary resection or following the final pathology result as a second procedure.
Further Outpatient Care:

Patients with BCC require lifelong follow-up care. In the initial period, perform
close examination of the primary tumor site to detect recurrence at an early
stage. During follow-up, examine the sun-exposed area of the skin to identify
second primary tumors. A general follow-up schedule calls for a 2-3 month
intervals for 2 years, with annual follow-up thereafter.
Deterrence/Prevention:

Prevention of BCC centers on measures to decrease UVR exposure. The peak
period of UVR occurs from 10 AM to 4 PM. Lifestyle modification, protective
clothing, and use of sunscreen preparations with a protective factor of 15 or more
should be considered. Initiation of preventive measures from childhood
decreases the incidence of BCC.

Patients with a high risk for BCC (eg, whites with Celtic ancestry), a previous
history of BCC, or a lifestyle involving excessive sun exposure should be
screened for BCC.
Complications:

Early postoperative complications

o
Bleeding
o
Infection
o
Loss of skin graft
Late postoperative complications
o
Facial scar
o
Ectropion
o
Epiphora
o
Tumor recurrence
Prognosis:

Incidence of recurrence following surgical excision is 30% in patients with a
positive margin, 12% in patients with a close margin, and less than 5% in
patients with a complete excision. With adequate treatment, a cure rate of more
than 95% can be expected. Recurrent tumors following radiotherapy have a low
tumor control rate.
Patient Education:

Counsel patients regarding the need for preventive measures to decrease UVR
exposure. The peak period of UVR occurs from 10 am to 4 pm. Advise patients
to wear of protective clothing and the use of sunscreen preparations with a
protective factor of 15 or more.

For excellent patient education resources, visit eMedicine's Cancer and Tumors
Center. Also, see eMedicine's patient education articles Skin Cancer and Skin
Biopsy.
MISCELLANEOUS
Section 8 of 10
Author Information Introduction Clinical Differentials Workup Treatment Follow-up Miscellaneous Pictures Bibliography
Medical/Legal Pitfalls:

Early BCC is an indolent lesion, which may be confused with other benign
dermatologic conditions, thus delaying diagnosis. Rule out BCC in elderly
patients who have any persistent nodular or scaly lesions in the upper two thirds
of the face.

Adequate excision of BCC results in a much wider defect than the clinical lesion.
Adequately prepare patients for the functional and aesthetic results of surgery.

During postoperative surveillance, take care to detect early recurrence and new
BCCs. Diagnosis of early recurrence may be difficult because of surgical
scarring, fibrosis, and the presence of skin graft. Delay in diagnosis of tumor
recurrence can affect the success of salvage treatment and its functional and
aesthetic results.
PICTURES
Section 9 of 10
Author Information Introduction Clinical Differentials Workup Treatment Follow-up Miscellaneous Pictures Bibliography
Caption: Picture 1. Basal cell carcinoma of the skin. A 68-year-old patient
presenting with an advanced basal cell carcinoma (BCC) of the right periorbital
region (frontal view).
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Picture Type: Photo
Caption: Picture 2. Basal cell carcinoma of the skin. Lateral view of face showing
extent of tumor.
View Full Size Image
Picture Type: Photo
Caption: Picture 3. Basal cell carcinoma of the skin. Intraoperative view outlining
the extent of resection (lateral view). The surgical resection consisted of zygomatic
bone and the lateral orbit. The eye was spared.
View Full Size Image
Picture Type: Photo
Caption: Picture 4. Basal cell carcinoma of the skin. Intraoperative view showing
the extent of resection (inferior view).
View Full Size Image
Picture Type: Photo
Caption: Picture 5. Basal cell carcinoma of the skin. The surgical defect was
reconstructed using a sensate osteocutaneous radial forearm free flap. The
osteotomized radial form was used to reconstruct the zygomatic bone and the
lateral orbital rim. To provide sensation to the flap, the antebrachial cutaneous
nerve was anastomosed to branches of the trigeminal nerve.
View Full Size Image
Picture Type: Photo
Caption: Picture 6. Basal cell carcinoma of the skin. Nodular basal cell carcinoma.
Nodular aggregates of basalioma cells are present in the dermis and exhibit
peripheral palisading (PP) and retraction artifact (RA). Melanin is also present
within the tumor and in the surrounding stroma, as seen in pigmented basal cell
carcinoma. Image courtesy Michael L. Ramsey, MD.
View Full Size Image
Picture Type: Photo
Caption: Picture 7. Basal cell carcinoma of the skin. Scale, erythema, and a
threadlike raised border are present in this superficial basal cell carcinoma on the
trunk. Image courtesy Michael L. Ramsey, MD.
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Picture Type: Photo
Caption: Picture 8. Basal cell carcinoma of the skin. Larger superficial basal cell
carcinoma. Image courtesy Michael L. Ramsey, MD.
View Full Size Image
Picture Type: Photo
Caption: Picture 9. Basal cell carcinoma of the skin. Histology of superficial basal
cell carcinoma. Nests of basaloid cells are seen budding from the undersurface of
the epidermis. Image courtesy Michael L. Ramsey, MD.
View Full Size Image
Picture Type: Photo
Caption: Picture 10. Basal cell carcinoma of the skin. Pigmented basal cell
carcinoma has features of nodular basal cell carcinoma with the addition of darker
pigmentation from melanin deposition. The pigmentation often has the appearance
of dark droplets within the lesion, as seen in this picture. Image courtesy Michael L.
Ramsey, MD.
View Full Size Image
Picture Type: Photo
Caption: Picture 11. Basal cell carcinoma of the skin. This infiltrating basal cell
cancer has ill-defined borders and telangiectases. Image courtesy Michael L.
Ramsey, MD.
View Full Size Image
Picture Type: Photo
Caption: Picture 12. Basal cell carcinoma of the skin. Postoperative wound after
Mohs micrographic surgery demonstrates extensive subclinical involvement typical
of many infiltrating and morpheaform basal cell carcinomas. Image courtesy
Michael L. Ramsey, MD.
View Full Size Image
Picture Type: Photo
Caption: Picture 13. Basal cell carcinoma of the skin. Large scarlike morpheaform
basal cell cancer. Image courtesy Michael L. Ramsey, MD.
View Full Size Image
Picture Type: Photo
BIBLIOGRAPHY
Section 10 of 10
Author Information Introduction Clinical Differentials Workup Treatment Follow-up Miscellaneous Pictures Bibliography


American Joint Committee on Cancer: Manual for Staging of Cancer. JB
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Skin Cancer: Basal Cell Carcinoma excerpt