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Skin cancer Non-melanoma

Basal cell carcinomaSquamous cell carcinomaDermatofibrosarcomaMerkel cell carcinomaKaposi sarcomaAngiosarcoma

Melanoma

Non-melanoma skin cancerNon-melanoma skin cancer

Non-melanoma skin cancer

Most common cancer in the USA

Over 1,000,000 new cases in the USA per year Fair skinned population

Risk factors

Environmental factors Sunlight exposure (Ultraviolet radiation)

Ionizing radiation Chemical exposure eg. arsenic agent

Patient factors Genetics disease Precursor lesion HIV and HPV infection

UV radiation

95%

More carcinogenic

Basal cell carcinoma


75% of non-melanoma skin cancerMale : female = 3:2Sunlight exposureHead & neckSlow growingRarely metastasizes

Basal cell carcinomaNodular

most common, pearly appearing papule

Pigmented more frequent in darker-skinned population

Cystic bluish or gray cystic nodule

Superficial scaly patch-like lesion pink to red to brown


Micronodularaggressive variant

Morpheaform (infiltrating)aggressive variantscar-like appearance with il

l-defined border

Squamous cell carcinoma


Second most common skin cancerMale : female = 2-3:1

Sunlight exposureOld scar, chronic inflammation and ulce

rArea of pre-exiting skin damageFaster growing


Actinic keratosis: precursorBowen's disease: SCC in-situUnhealed ulcer with "heaped up" edgeEnlarging lesion irregular borderCranial nerve dysfunction

perineural invasion

Diagnosis

Clinical diagnosis Incisional / excisional biopsy Imaging

TreatmentTreatment

Surgical excision

Major treatment methodHigh clearance rate

~95% in both SCC and BCC Low recurrence rate (in 5 year)

5.8% in SCC, <2% in BCC

N.R. Telfer et al. British J of Dermatology. 2008Murad Alam et al. N Engl J Med. 2001

How much marginmargin should we take?

BCCLesion Low risk

Trunk & extremities <2cm Head &neck <1cm Around eyes, ears, nose, mouth, hand and fe

et <6mm

High risk Recurrent tumor Immunocompromised Previous radiation site Perineural invasion Micronodular, sclerosing, morpheaform

Margin (mm)

4-5

10

SCCLesion Low risk

Trunk & extremities <2cm Head &neck <1cm Around eyes, ears, nose, mouth, hand and feet <6

mm

High risk Recurrent tumor Immunocompromised Previous radiation site Perineural invasion Poorly differentiated Adenoid, adenosquamous, desmoplastic

Margin (mm)

4-5

10

Facial H area

Mohs' micrographic surgery Frederic E. Mohs in 1938 Complete circumferential peripheral and deep margin

assessment Performed in stages / single day

5 year local control rateSCC BCC

Primary 96.9% 99%

Recurrent 90-93.3% 94.4%

Murad Alam et al. N Engl J Med. 2001Nicole W.J. et al. The Lancet 2004

Mohs' micrographic surgery

Preserve healthy skin tissue Time consuming High cost

Mohs' micrographic surgeryImportant site:

eyelids, ear, nose, lips, nasolabila fold, forehead, scalp or embryonic fusion plane

RecurrenceSize >2cmPerineural involvementPoorly defined margins in high-risk area

Nicole W.J. et al. The Lancet 2004

Radiation therapyPrimary vs adjuvant5-year local control rate ~90%Multiple visitsNo histological resultSide effect: dermatitis, telangiectasia

Contraindication:Genetic condition eg. xeroderma pigmentosaConnective tissue disease

I.R. Aguayo-Leiva et al. Actas Dermosifiliogr. 2010

Electrodesiccation and CurettageIndication:

Small lesion <1cmSuperficialWell-defined

5-year local control rate: 95% in low risk BCC

Multiple attemptsNo histopathology

I.R. Aguayo-Leiva et al. Actas Dermosifiliogr. 2010N.R. Telfer et al. British J of Dermatology. 2008

CryotherapyLiquid nitrogenFrozen the skin -> tissue necrosis

Multiple cycles5-year recurrence rate: 8% in low risk BCCNo histopathologyGood cosmetic result


CryotherapyIndication: Low risk BCC

Size <1cmSuperficial, nodular Well-defined margin


Topical immunotherapy Imiquimod

Toll-like receptor 7 agonist Modify the immune response -> antitumor activity -> tumor cell apoptosis 5 application a week for 6 week

Indication: Small superficial BCC Initial response rate 89.6% Lack of long term data Excellent cosmetic result


Photodynamic therapyPhotosensitizing agent followed by illu

mination of visible lightProduced activated oxygen molecule ->

destroy target cellUsually 2 cycles5-year recurrence rate: 14%Excellent cosmetic effect


Photodynamic therapyLimited penetrationIndication:

Superficial lesionDepth <2mm


5-Fluorouracil Topic chemotherapeutic agent Blocking DNA synthesis Apply twice a day for minimum 6 week Cure rate: 93%

Indications:Superficial BCCSmall ~1cm

Local inflammatory response


InterferonIntralesional injectionInduce apoptosis3 injections per week for 3 weekComplete response rate: 50-80%

Indications:Surgery could be disfiguringNot a surgical candidate

Influenza-like symptom


Conclusion

Non-melanoma skin cancer Common Rate of cure is high with proper treatment in local di

sease Surgical excision is associated with lowest recurrenc

e rate Other non-surgical treatment

Early superficial diseaseNon-surgical candidates

Thank you

SLN

No definite guideline Lack of large scale study on non-melanoma sk

in cancer Renzi et al.: 22 patients Reschly et al.: 9 patients

Useful in high risk SCC

Involved margin

~30-41% do not recur

Re-excision of margin Mohs micrographic surgery Radiotherapy

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