Skin Cancers and Melanoma

Presentations (Melanoma)

A: Asymmetry B: Border irregular or Bleeding C: Color variegation D: Diameter (> 5mm) E: Elevation or Enlargement

Managment (Skin cancers)

Depends on histology, anatomic site, underlying medical status, and whether the tumor is primary or recurrent. Surgery: Excission (simple surgical versus wide local excision) Mohs micrographic surgery Curettage and electrodessication Cyrosurgery

Radiation Therapy (Nonmelanoma)

Dose Schedule: - BCC -- Smaller than 2 cm -- 4500 cGy -- 2 to 5 cm -- 5000 cGy -- Larger tahn 5 cm -- 6000 cGy - SCC -- Smaller than 2 cm -- 5000 cGy -- 2-5 cm -- 5500 cGy -- Larger than 5cm -- 6500 cGy Lesions larger than 8 cm or with bone invasion -- 65-75 Gy

Clinical Presentation (Merkel cell)

Origin uncertain: epithelial Merkel cell with neuroendocrine differentiation versus totipoent stem cell with neuroendocrine differentiation. Risk factos: UV radiation, immunosuppression, Merkel cell polyomavirus. Histologically mimic small cell cancer of lung. Very aggressive. High prevalence of local microscopic infiltration and satellite mets. Most common in head and neck -- also involved extremetities. LN involvement common: 20-30% at presentation, and less than 50% at some point of disease and developement if untreated. May mets to distant site (occures in less than 1/3 of patients)

Radiation Therapy (Skin Cancer)

Primary therapy: For cancer around nose, eyelids, ears, RT provide better cosmetic and functional results Post-op RT: positivie margins, perineural invasion, bone or cartilage or extensive muscle involvement

Radiation Therapy (BCC)

Radiation (Cure rates of 90% plus, lower to similar success if recurrent) - Patients who are poor candidates for surgical management - High recurrence risk patients --- less than 6 mm in H zone --- less than ten to 20 mm elsewhere --- recurrent tumors --- poorly defined borders --- perineural invasion - Sites such as eyelids, nose, and lips where surgery would be associated with significant functional and cosmetic deficit.

Management (Melanoma)

Stage 1 and 2: Biopsy: Excisional -- preferred Incisional -- reversed only for large lesions Work-up: CXR, LFT for later stages Surgical resection: local recurrence (within 3-5 cm of primary) is low, about 3% or less Wide resection with a margin of 2 cm of tumor less than 1 mm thick Deep margin down to but not including fascia Post-operative radiotherapy may be considered in high risk situations (e.g. positive margins, desmoplastic histology) Sentinal LN Biopsy?? Stage 3: Wide excision Complete LN dissection (or clinical trial) Stage 4: Promising new drug therapies and strategies YERVOY (ipilimumab) -- immune system ZELBORAF (vemurafenib) -- cellular pathways

Types (Melanoma)

Superficial spreading Nodular Lentigo maligna Acral lentiginous Desmoplastic (aggressive)

Management (BCC)

Surgical or ablative therapies preferred for appropriately selected patients (MOHS, excision, staged excision, ED and C)

Epidemiology (Non-Melanoma Skin Cancers)

Non melanoma incidence: Over a million new cases annually - 80% BCC - 20% SCC Deaths: 1000-2000

Side effects (skin cancers)

Acute: Skin changes Alopecia Chronic: Telangiectasis Hyperpigmentation Hair loss Necrosis Fibrosis Permanent Skin changes

Management (MCC)

Adjuvant radiation follwing surgery may only be needed for high risk patients, but this depends on who you talk to.

Staging (Melanoma)

Clark's stage (largely replaced by tumor thickness measurements): Level 1 -- confined to epidermis Level 2 -- Invasion through the basement membrane to the papillary dermis Level 3 -- Invasion to junction of the papillary and reticular dermis Level 4 -- extends into the reticular dermis Level 5 -- penetration into subcutaneous tissue

Risk Factors

Environmental: Sun exposure is the main etiologic facture (SCC, BCC, melanoma) - Evidence: - Occurs in sun-exposed areas. - More common in outdoor people - More common in fair skinned people than dark skinned people. - Depletion of ozone increase UV exposure and skin cancer incidence -Mechanism: - UV light induced DNA damage (DNA photoproducts, especially TT dimer formation) - Failure of DNA damage repair leads to gene mutation Chemical carcinomgen exposure (SCC, BCC) - Arsenic, tar, anthracene, crude paraffin oil Ionizing radiation (SCC, BCC) Smoking (SCC, BCC) Genetic: Xeroderma pigmentosum -- inability to repair DNA damage (SCC, BCC, melanoma) Epidermolysis bullosea (SCC ((Very aggressive)), BCC) Epidermodysplasia verruciformis -- unusual susceptibility to HPV infection (SCC) Basal cell nervus syndrome (BCC) Albinism Other: Age Immunosuppression (SCC more than BCC) -- also increases aggressiveness of tumor. Chronic inflammation from scars, burns, chronic wounds (Marjolin's ulcer) (SCC) HPV infection

Growth Pattern (Melanoma)

Horizonal Vertical

Clincal Representation (Squamous Cell)

Keratinizing cells from squamous epithelial cells More aggressive than BCC, but may still be slow growing. Common in sun exposed areas (back of hand, temples, cheeks, scalp, lip, top of ear) Actinic Keratosis is considered precancerous lesion with low rate of progression Bowmen's disease: SCC in situ (confined to epidermis, does not invade the dermis) Can develop in area of inflammator or trauma -- burn scar or chronic site of infection (Marjolin ulcer) Can invade deeper tissue and neighboring tissue and organs Mets rate (1-5% overall) High risk features: arising at borders of embryonic fusion plates (H zone of the face), arise from chronic inflammation, radiation induced, immunosuppressed patient. What is the H-Zone? Frontal and Temporal Cheek and Chin Nasal and Perinasal Lips Periocular Ears Periaricular

Management (SCC)

Low risk tumors: Cryotherapy, ED and C, excision, for low risk tumors. Radiation for those who are older, not surgical candidates High risk tumors: (large, recurrent, perineural invasion, extension beyond subcutaneous tissue) - Radiation - Excision and MOHS (post op RT for even higher risk patients) - Note: Recurrent SCC worse than recurrent BCC

General (Melanoma)

Melanocytes are distributed singly in the basal layer between basal cells, providing melanin to ther epidermis, which protect skin from UV damage. Melanocytes originated from the neural crest, migrated to the skin during embryonic developement Melanoma is significantly different from other skin cancer in biology, presentation, treatment, and prognosis. Closely associated with UV exposure The 6th and 7th leading cancer in US men and women 8-9000 deaths per year The most common fatal malignancy among young adults Early detection is the key for successful treatment Risk of mets is associated with depth of tumor invasion 30% arise in preexisting melanocytic lesions and 70% arise in normal skin Mostly affects whites, incidence in African American 1/20 of white Mostly affect young and middle aged people, but can occur at any age.

Radiation Therapy (melanoma)

Melanoma initailly considered relatively radioresistant Some data suggesting benefit to hypofractionation (but other data is less convincing) Rarely used as primary therapy Post-op RT may reduce local recurrence but not necessarily overall survival

General (Skin Cancer)

Most common Melignancy Types: Melanoma -superficial spreading melanoma - lentigo maligna - acral lentiginous melanoma - nodular melanoma Nonmelanoma - basal cell carcinoma - squamous cell carcinoma - merkel cell carcinoma

Epidemiology

Most common type of cancer in the US Incidence increased significantly in the last decade, especially melanoma. 11,200 people each year die of cutaneous cancer (75% due to melanoma, although it comprises only 3% of all skin cancers) 1 million non-melanomatous skin cancer per year 62,500 melantomatous skin cancers per year

Clinical Representation (Basal Cell)

Non keratininzing cells originating from basal layer Most commonly seen in the sun exposed areas (head and neck); more common in whites, uncommon in dark skinned Rolled borders -- "pearly papule" with telangiectasias Superficial BCC can present with erythematous, thin plaque, or scaly macule Spread laterally, but rately mets (less than .1%) 30% occur in nose, can be aggressive and destructive, especially if neglected or with deep invasion.

Prognosis (Skin Cancers)

Non melanoma -- 95% early stage Melanoma -- 85% all stages - rapid vertical growth typical - Risk of nodal or mets involvement increases with increased tumor depth