Dermatology 5

26/05

Which gene is most frequently associated with Acral Lentiginous Melanoma? (explain relevance in 1 sentence)

c-KIT gene. Treatment implication: targeted by Imatinib

List the most important drugs in treatment of metastatic melanoma

• Tyrosine kinase inhibitors

  • BRAF/MEK inhibitors

  • c-KIT inhibitors

• Immune checkpoint inhibitors

  • anti-CTLA4 monoclonal antibodies

  • anti-PD1 monoclonal antibodies

What are the typical dermoscopy features that enable us to distinguish between acral melanoma and acral nevus?

The presence of parallel ridge pattern (pigmentation on the ridges of acral skin) is a hallmark of acral melanoma

Explain the clinical progression to lentigo maligna melanoma

Chronic UV-radiation exposure leads to Lentigo Maligna (precursor/in situ lesion in the horizontal growth phase) presenting as a macula with suspicious features (ABCDE, ugly duckling sign, etc.) generally on the face, scalp and ears. When not excised, it progresses in 90-95% of cases to Lentigo Maligna Melanoma (invasive melanoma in vertical growth phase) typically presenting as a dark nodule over the macula.

Explain when Mohs micrographic surgery is preferred for treatment of basal cell carcinoma

Mohs micrographic surgery is preferred in the treatment of BCC in these cases:

• Tumor is located in high-risk or cosmetic sensitive area (e.g. face, nose, eylids, ears)

• Recurrent lesion

• Aggressive histological subtype (morpheaform, infiltrative)

• Poorly defined margins.

It gives the highest cure rate with maximal tissue preservation.

Which are the most common sites of seborrheic dermatitis and why?

The most common sites are:

• Sternal area

• Scalp

• Face (forehead, paranasal/nasolabial region, chin, eyebrows, eyelids, jaw, beard area)

The reason is that in these regions there is a higher quantity of sebaceous glands.

List and define what are the key histopathological features of the dermis and epidermis in psoriasis

DERMIS:

• Dilation of blood vessels

• Lymphocyte infiltration

EPIDERMIS:

1. Parakeratosis: thickening of the stratum corneum with presence of nucleated cells

2. Munro’s microabscesses: abscesses in the stratum corneum of the epidermis due to infiltration of neutrophils from the papillary dermis into the stratum corneum

3. Pustules of Kogoy: sterile collections of neutrophils in the stratum spinosum

4. Acanthosis: thickening of the whole epidermis

5. Hypogranulosis: decreased or absent granular layer in the epidermis

List the endogenous risk factors of melanoma (7)

1. MC1R gene variations

2. Germline mitations (CDKN2A, CK4)

3. Personal or family history

4. Individual with numerous nevi

5. Presence of atypical nevi

6. Congenital melanocytic nevus >20cm

7. Fair skin phototypes

List the exogenous risk factors of melanoma

1. Chronic UV radiaiton exposure

2. Sunburns

3. Artificial UV sources

4. Geographical and environmental factors

5. Iatrogenic immunosuppression (e.g. organ-transplant patients)

List the treatment used in actinic keratosis: those indicated for single lesions and those used for field cancerization.

TREATMENT FOR SINGLE LESIONS:

• Cryotherapy

• Curettage and cautery

• Laser therapy

FOR FIELD CANCERIZATION:

• Photodynamic therapy

• Topical treatments, including

  • 5-Fluorouracil (creaml formulations, sometimes combined with salicylic acid)

  • Imiquimod

  • Diclofenac

  • Tirbanibulin

Define Kaposi sarcoma and list the types

Kaposi sarcoma is a low-grade angioproliferative tumor mainly associated with HHV-8 infection.

• Classic Kaposi sarcoma

• Endemic (African) Kaposi sarcoma

• Epidemic (AIDS-related) Kaposi sarcoma

• Iatrogenic (transplant-related) Kaposi sarcoma

What is the most important and quickest step in the diagnosis of gonorrhea?

Gram stain detects the gram-negative diplococci in urethral discharge.