Basal cell carcinoma - American Academy of Dermatology

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Basal Cell Carcinoma
Basic Dermatology Curriculum
Updated September 6, 2011
1
Module Instructions
 The following module contains a number of
underlined terms which are hyperlinked to
the dermatology glossary, an illustrated
guide to clinical dermatology and
dermatopathology.
 We encourage the learner to read all the
hyperlinked information.
2
Goals and Objectives
 The purpose of this module is to help medical students
develop a clinical approach to the evaluation and initial
management of patients presenting with suspicious
lesions.
 By completing this module, the learner will be able to:
• Identify and describe the morphology of basal cell
carcinoma
• Formulate a differential diagnosis based on the patient’s
history and physical findings
• Refer patients with skin lesions suspicious for nonmelanoma skin cancer to dermatology
3
Clinical Case History
 Mr. Carter is a 62-yearold man who presents
to your office with a
growth by his right ear.
He first noticed the
growth about six months
ago. He states that it
has increased in size,
but it otherwise does not
bother him.
4
You learn more about Mr. Carter’s
history…
 Past Medical History:
• Extensive history of sun exposure, especially in childhood
• Fair skin, usually burns, rarely tans
• No history of skin cancer
• No history of arsenic exposure or radiation
• Hypertension, dyslipidemia, diabetes
 Medications: Aspirin, Insulin, Lisinopril, Simvastatin
 Family history: No history of skin cancer
 Social history: Married with 3 children.
 Health-related behaviors: 10-pack year smoking history;
quit 10 years ago. No alcohol or drug use.
5
© 2009 A. Garg, MD
How would you describe his facial
growth?
6
© 2009 A. Garg, MD
How would you describe his facial
growth?
Solitary, 5 mm pearly pink papule with telangiectasias
7
What is your differential diagnosis?
After you have considered the differential
diagnosis, go to the next slide for a list of
possible diagnoses.
8
What is your differential diagnosis?
•
•
•
•
•
Basal cell carcinoma
Intradermal nevus
Sebaceous hyperplasia
Seborrheic keratosis
Squamous cell carcinoma
9
Evaluation
 What is your next step in evaluating this
patient?
a.
b.
c.
d.
e.
Liquid nitrogen cryotherapy
Reassurance with close follow-up
Shave biopsy
Surgical removal
Topical antibiotics
10
Evaluation
Answer: c
 What is your next step in evaluating this patient?
a. Liquid nitrogen cryotherapy (cyrotherapy will not help
diagnose the lesion)
b. Reassurance with close follow-up (this is a suspicious
lesion and should be biopsied)
c. Shave biopsy
d. Surgical removal (best to biopsy the growth in order to
obtain histologic confirmation prior to surgical
removal)
e. Topical antibiotics (the lesion does not appear to have
11
a bacterial etiology)
Shave Biopsy Reveals…
• Rounded nests of
“basaloid” cells
• Peripheral palisading
• Fibromyxoid stroma
• Cleft formation
12
Ordering Pathology
 Note that the pathologist did not comment
on the margins
 This is because we ordered a biopsy (for
diagnosis) and not an excision (to confirm
it is all out)
 Click here to watch a video on pathology
requests
13
Shave Biopsy
 Click here to watch a video on local
anesthesia
 Click here to watch a video on how to
perform a shave biopsy
14
What is the diagnosis?
a.
b.
c.
d.
e.
Basal cell carcinoma
Intradermal nevus
Sebaceous hyperplasia
Seborrheic keratosis
Squamous cell carcinoma
15
What is the diagnosis?
Answer: a
a. Basal cell carcinoma
b. Intradermal nevus (Pigmented or skin colored, appears early in life, and
would not be expected to develop in this age group. Histologically,
melanocytic nevi show nests of nevo-melanocytic cells in the dermis,
without palisading or clefting)
c. Sebaceous hyperplasia (Can have telangiectasias but tend to be yellowish
or pink. Histologically, they show groups of normal looking sebaceous
glands)
d. Seborrheic keratosis (Verrucous (irregular surfaced) and NOT smooth.
Also, they are not pearly and do not have surface telangiectasias.
Histologically, they show thickend and verrucous epidermis with keratin
cysts)
e. Squamous cell carcinoma (Red nodule with keratin. Histologically, there
are atypical keratinocytes in the epidermis and invading the dermis)
16
Management
 What is your next step in management?
a.
b.
c.
d.
e.
Shave biopsy
Liquid nitrogen cryotherapy
Reassurance with close follow-up
Surgical removal
Topical antibiotics
17
Management
Answer: d
 What is your next step in management?
a. Shave biopsy (You already have a diagnosis and there is no need
for another biopsy)
b. Liquid nitrogen cryotherapy (Liquid nitrogen cryotherapy is the
treatment of choice for several benign and pre- cancerous skin
lesions (e.g. actinic keratoses). It is not 1st-line treatment for BCC)
c. Reassurance with close follow-up (Basal cell carcinomas are
malignant and produce significant local tissue destruction. They
must be treated early)
d. Surgical removal (The treatment of choice for basal cell carcinoma
is surgical excision. Alternatively, electrodesiccation and curettage
or radiation therapy can be used)
e. Topical antibiotics (Basal cell carcinoma is a tumor not an infection)
18
Biopsy vs. Excision
 How come we did not excise the whole lesion to
begin with?
 It is best to biopsy the growth in order to obtain
histologic confirmation prior to surgical removal, as
biopsy may have revealed:
• A benign growth, in which case excision would have
been unnecessary
• A tumor different from BCC that may have required a
different management approach
19
At the follow-up visit 6 months
later…
 Mr. Carter healed well following surgical removal.
There is no evidence of tumor recurrence or new
primary tumors.
 You counsel Mr. Carter on the importance of
continued sun protection and regular self-skin
exams, and you schedule him for routine full-skin
exams every 6 months to a year in order to monitor
for skin cancers.
Now, let’s review Basal Cell Carcinoma
20
Basal cell carcinoma (BCC)
 Most common skin cancer
• >1 million new cases per year in the US
• Neoplasm arises from nonkeratinizing
keratinocytes that originate in the basal layer of
the epidermis
 Etiology
• Ultraviolet radiation induces DNA damage
• PTCH (tumor suppressor gene) mutation
– Spontaneous/acquired mutations from UV-induced
DNA damage
21
Basal cell carcinoma (BCC)
 Risk factors
• Skin types I, II (fairer skin types)*
• History of intense or prolonged ultraviolet light
exposure
• History of ionizing radiation exposure or arsenic
ingestion
• Immune suppression (transplant patients, systemic
immunosuppressive medications)
• Genetic conditions that increase skin cancer risk
* BCC is still commonly seen in darker skin types
22
Classifying Skin Types
 The Fitzpatrick Skin Phototype Classification is used
to classify skin based on the ability to burn and tan
when challenged with UV radiation
I.
II.
III.
IV.
V.
VI.
White skin, always burns, never tans
White skin, always burns, minimal tan
White skin, burns minimally, tans moderately and gradually
Light brown skin, burns minimally, tans well
Brown skin, rarely burns, tans deeply
Dark brown/black skin, never burns, tans deeply
Note: sunscreen is recommended for all skin types, including the darkest
of skin
23
There are other clinical subtypes of
BCC:
24
Nodular BCC
 Most common subtype
 Presents as a pearly
papule or nodule with
rolled border and
telangiectasias
 Although any part of the
body may be involved,
the lesions are most
frequently found on the
head and neck
25
Superficial BCC
 Presents with features
suggestive of BCC including
a pink or translucent color,
telangiectasia, and a slightly
rolled border
 Morphology is a patch or a
thin plaque, which may be
scaly
 Differential diagnosis may
include squamous cell
carcinoma in situ or actinic
keratosis
26
Ulcerated BCC
 Presents with features
suggestive of BCC
including a translucent
color, telangiectasia, and
a rolled border
 In addition, the growth is
grossly or microscopically
ulcerated, which often
results in crusting over
the growth
27
Pigmented BCC
 Presents with features
typical of a BCC along
with globules of dark
pigment
 The differential
diagnosis may include
malignant melanoma
28
Morpheaform BCC
 Presents with features
suggestive of BCC
including a translucent
color, telangiectasia,
and a rolled border
 In addition, the plaque
appears white and
bound down or scar-like
in areas
29
BCC: Treatment
 There are several surgical and non-surgical
treatment options.
 The best option is selected after
consideration of clinical and histologic
features.
 To select the optimum therapy, refer to a
dermatologist
30
BCC: Treatment
 Surgical Treatment Options:
•
•
•
•
Curette and Desiccation
Cryosurgery
Excision with standard 3-4mm margins
Mohs micrographic surgery – permits real time evaluation of tumor
margins and consequent tissue conservation to minimize defect
size
 Non-Surgical Treatment Options:
•
•
•
•
Imiquimod cream – FDA approved for superficial BCC
5% fluorouracil cream for superficial BCC
Photodynamic therapy for superficial BCC
Radiation
31
Mohs Micrographic Surgery (MMS)
 MMS offers superior histologic analysis of tumor margins
while permitting maximal conservation of tissue compared
with standard surgical excision
 Recurrence rates tend to be lower with MMS compared to
other modalities, including standard excision, curettage and
desiccation, radiation, and cryotherapy
 Indications include:
• Location: nose, ears, eyes, lips, scalp, hands
• Aggressive histologic subtypes: infiltrative, sclerosing,
morpheaform, or micronodular
• Large tumors or tumors with indistinct clinical borders
• Recurrent tumors
32
Mohs Micrographic Surgery
Step 1: The roots of a skin cancer may extend
beyond the visible portion of the tumor. If these
roots are not removed, the cancer will recur.
Step 2: The visible tumor is surgically
removed.
Step 3: A layer of skin is removed and divided
into sections. The surgeon then color codes
each of these sections with dyes and makes
reference marks on the skin to show the
source of these sections. A map of the surgical
site is then drawn.
Mohs Micrographic Surgery
Step 4: The undersurface and edges of each
section are microscopically examined for evidence
of remaining cancer.
Step 5: If cancer cells are found under the
microscope, the surgeon marks their location onto
the "map" and returns to the patient to remove
another layer of skin - but only from precisely
where the cancer cells remain.
Step 6: The removal process stops when there is
no longer any evidence of cancer remaining in the
surgical site.
BCC: Course & Prognosis
 BCC is locally invasive
 Metastasis is rare
 Patients with BCC are at risk for
developing other non-melanoma and
melanoma skin cancers
 They should have follow-up at regular
intervals (e.g. every 6 months to 1 year)
35
Patient Education
 There are multiple resources to help educate
patients about sun safety and skin cancer
prevention, including:
• American Academy of Dermatology: Skin
Cancer Prevention
• American Cancer Society: Skin Cancer
Prevention and Early Detection
 The following slides are adapted from the AAD
Be Sun Smart® program
36
Patient Education: Be Sun Smart®
 Generously apply a broad-spectrum, water-resistant
sunscreen with a Sun Protection Factor (SPF) of 30 or more
to all exposed skin.
• “Broad-spectrum” provides protection from both UVA and UVB rays.
• Reapply approximately every two hours, even on cloudy days, and
after swimming or sweating.
 Wear protective clothing, such as a long-sleeved shirt,
pants, a wide-brimmed hat, and sunglasses.
 Seek shade.
• Remember that the sun's rays are strongest between 10 AM – 4PM.
• If your shadow appears to be shorter than you are, seek shade.
37
Patient Education: Be Sun Smart®
 Use extra caution near water, snow, and sand because
they reflect and intensify the damaging rays of the sun, which
can increase your chances of a sunburn.
 Get vitamin D safely through a healthy diet that may include
vitamin supplements. Don't seek the sun.
 Avoid tanning beds. Ultraviolet light from the sun and
tanning beds can cause skin cancer and wrinkling. If you want
to look tan, consider using a self-tanning product, but
continue to use sunscreen with it.
 Check your birthday suit on your birthday. If you notice
anything changing, growing, or bleeding on your skin, see a
dermatologist.
38
How to perform a skin self-examination
Examine your body front
and back in the mirror,
then look at the right
and left sides with your
arms raised.
Look at the backs of
your legs and feet, the
spaces between your
toes, and the soles of
your feet.
Bend elbows and look
carefully at forearms,
upper underarms, and
palms.
Examine the back of
your neck and scalp
with a hand mirror.
Part hair for a closer
look.
39
Take Home Points
 BCC is the most common skin cancer
 It is most common in the head and neck
 BCC is locally destructive but metastases are
extremely rare
 Diagnosis is established by biopsy
 Treatment depends on clinical and histological
features but is usually surgical
 Educate patients about skin cancer prevention
40
Acknowledgements
 This module was developed by the American Academy of
Dermatology Medical Student Core Curriculum Workgroup from
2008-2012.
 Primary authors: Amit Garg, MD, FAAD; Lisa Nguyen, MD;
Meera Mahalingam, MD.
 Contributor: Sarah D. Cipriano, MD, MPH.
 Peer reviewers: Timothy G. Berger, MD, FAAD; Patrick
McCleskey, MD, FAAD; Carlos Garcia, MD; Isaac M. Neuhaus,
MD, FAAD.
 Revisions: Sarah D. Cipriano, MD, MPH. Last revised
September, 2011.
 Thank you to the American College of Mohs Surgery for
providing images of the Mohs surgery process
41
References






Carucci John A, Leffell David J, "Chapter 115. Basal Cell Carcinoma" (Chapter).
Wolff K, Goldsmith LA, Katz SI, Gilchrest B, Paller AS, Leffell DJ: Fitzpatrick's
Dermatology in General Medicine, 7e:
http://www.accessmedicine.com/content.aspx?aID=2954299.
Chartier TK. Treatment and prognosis of basal cell carcinoma. In: UpToDate,
Basow, DS (Ed), UpToDate, Waltham, MA, 2011.
James WD, Berger TG, Elston DM, “Chapter 29. Epidermal Nevi, Neoplasms, and
Cysts” (chapter). Andrews’ Diseases of the Skin Clinical Dermatology. 11th ed.
Philadelphia, Pa: Saunders Elsevier; 2011: 633-637.
McGovern TW and Leffell DJ. Actinic Keratoses and Non-Melanoma Skin Cancer,
Clinical Dermatologic Curriculum for Medical Students, http://www.aad.org.
Neville JA, et al. Management of nonmelanoma skin cancer in 2007, Nat Clin Pract
Oncol, 2007;4(8):462-9.
Wolff K, Johnson RA, "Section 11. Precancerous Lesions and Cutaneous
Carcinomas" (Chapter). Wolff K, Johnson RA: Fitzpatrick's Color Atlas & Synopsis
of Clinical Dermatology, 6e:
http://www.accessmedicine.com/content.aspx?aID=5186831.
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Additional Resources
 Berger T, Hong J, Saeed S, Colaco S, Tsang M, Kasper R. The Web-Based
Illustrated Clinical Dermatology Glossary. MedEdPORTAL; 2007. Available
from: www.mededportal.org/publication/462
 Nguyen L, Mahalingam M, Garg A. Dermatology Clinical Case Modules: 62Year-Old Man With a Facial Growth. MedEdPORTAL. 2010; Available from:
http://services.aamc.org/30/mededportal/servlet/s/segment/mededportal/?subi
d=7751
 Nguyen L, Mahalingam M, Garg A. Dermatology Clinical Case Modules: 70Year-Old Man with a Red Crusty Bump on his Right Arm. MedEdPORTAL;
2010. Available from:
http://services.aamc.org/30/mededportal/servlet/s/segment/mededportal/?subi
d=8055
 Nguyen L, Mahalingam M, Garg A. Dermatology Clinical Case Modules: 40year-old Woman with a Dark Mole. MedEdPORTAL; 2010. Available from:
http://services.aamc.org/30/mededportal/servlet/s/segment/mededportal/?subi
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d=8067
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