1. Medical Student Core Curriculum in Dermatology
Basal Cell Carcinoma
Medical Student Core Curriculum
in Dermatology
Updated September 6, 2011

2. Module Instructions
The following module contains a number of underlined terms which are hyperlinked to the dermatology glossary, an illustrated interactive guide to clinical dermatology and dermatopathology.
We encourage the learner to read all the hyperlinked information.

3. 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 non- melanoma skin cancer to dermatology

4. Clinical Case History
Mr. Carter is a 62-year-old 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.

5. 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.

6. How would you describe his facial growth?
© 2009 A. Garg, MD

7. How would you describe his facial growth?
© 2009 A. Garg, MD
Solitary, 5 mm pearly pink papule with telangiectasias

8. What is your differential diagnosis?
After you have considered the differential diagnosis, go to the next slide for a list of possible diagnoses.

9. What is your differential diagnosis?
Basal cell carcinoma
Intradermal nevus
Sebaceous hyperplasia
Seborrheic keratosis
Squamous cell carcinoma

10. Evaluation What is your next step in evaluating this patient?
Liquid nitrogen cryotherapy
Reassurance with close follow-up
Shave biopsy
Surgical removal
Topical antibiotics

11. Evaluation
Answer: c
What is your next step in evaluating this patient?
Liquid nitrogen cryotherapy (cyrotherapy will not help diagnose the lesion)
Reassurance with close follow-up (this is a suspicious lesion and should be biopsied)
Shave biopsy
Surgical removal (best to biopsy the growth in order to obtain histologic confirmation prior to surgical removal)
Topical antibiotics (the lesion does not appear to have a bacterial etiology)

12. Shave Biopsy Reveals… Rounded nests of “basaloid” cells
Peripheral palisading
Fibromyxoid stroma
Cleft formation

13. 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

14. Shave Biopsy Click here to watch a video on local anesthesia
Click here to watch a video on how to perform a shave biopsy

15. What is the diagnosis? Basal cell carcinoma Intradermal nevus
Sebaceous hyperplasia
Seborrheic keratosis
Squamous cell carcinoma

16. What is the diagnosis? Answer: a Basal cell carcinoma
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)
Sebaceous hyperplasia (Can have telangiectasias but tend to be yellowish or pink. Histologically, they show groups of normal looking sebaceous glands)
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)
Squamous cell carcinoma (Red nodule with keratin. Histologically, there are atypical keratinocytes in the epidermis and invading the dermis)

17. Management What is your next step in management? Shave biopsy
Liquid nitrogen cryotherapy
Reassurance with close follow-up
Surgical removal
Topical antibiotics

18. Management Answer: d What is your next step in management?
Shave biopsy (You already have a diagnosis and there is no need for another biopsy)
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)
Reassurance with close follow-up (Basal cell carcinomas are malignant and produce significant local tissue destruction. They must be treated early)
Surgical removal (The treatment of choice for basal cell carcinoma is surgical excision. Alternatively, electrodesiccation and curettage or radiation therapy can be used)
Topical antibiotics (Basal cell carcinoma is a tumor not an infection)

19. 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

20. 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

21. 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

22. 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

23. 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
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

24. There are other clinical subtypes of BCC:

25. 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

26. 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

27. 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

28. Pigmented BCC
Presents with features typical of a BCC along with globules of dark pigment
The differential diagnosis may include malignant melanoma

29. 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

30. 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

31. 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

32. 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

33. Mohs Micrographic Surgery
Need to get permission

34. 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: SPOT Skin Cancer™ initiative
American Cancer Society: Skin Cancer Prevention and Early Detection
The following slides are adapted from the AAD SPOT Skin Cancer™ program and reflect recent, Board-approved changes to public messages about sun safety:

36. Patient Education: SPOT Skin Cancer™
Seek shade when appropriate. Remember that the sun's rays are strongest between 10 a.m. and 2 p.m. If your shadow appears to be shorter than you are, seek shade.
Wear protective clothing, such as a long-sleeved shirt, pants, a wide-brimmed hat, and sunglasses, where possible.
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 ultraviolet A (UVA) and ultraviolet B (UVB) rays. Reapply approximately every two hours, even on cloudy days, and after swimming or sweating.

37. Patient Education: SPOT Skin Cancer™
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 sunburn.
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 or spray, but continue to use sunscreen with it.

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.
Examine the back of your neck and scalp with a hand mirror. Part hair for a closer look.
Bend elbows and look carefully at forearms, upper underarms, and palms.

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
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.

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:
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:
McGovern TW and Leffell DJ. Actinic Keratoses and Non-Melanoma Skin Cancer, Clinical Dermatologic Curriculum for Medical Students,
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:

42. Additional Resources
Berger T, Hong J, Saeed S, Colaco S, Tsang M, Kasper R. The Web-Based Illustrated Clinical Dermatology Glossary. MedEdPORTAL; Available from:
Nguyen L, Mahalingam M, Garg A. Dermatology Clinical Case Modules: 62- Year-Old Man With a Facial Growth. MedEdPORTAL. 2010; Available from: d=7751
Nguyen L, Mahalingam M, Garg A. Dermatology Clinical Case Modules: 70- Year-Old Man with a Red Crusty Bump on his Right Arm. MedEdPORTAL; Available from: d=8055
Nguyen L, Mahalingam M, Garg A. Dermatology Clinical Case Modules: 40- year-old Woman with a Dark Mole. MedEdPORTAL; Available from: d=8067