Lesson 4: Integumentary Pathophysiology
The skin is the body's largest organ and serves as the first line of
defense against external threats. It protects you in several ways:
Barrier Function: The skin acts as a physical barrier that prevents
pathogens, chemicals, and physical abrasions from entering the body.
UV Protection: Melanin in the skin absorbs and dissipates ultraviolet
(UV) radiation, protecting deeper tissues from UV damage.
Temperature Regulation: Sweat glands and blood vessels in the skin help
regulate body temperature through sweating and
vasodilation/vasoconstriction.
Sensory Reception: The skin contains sensory receptors that detect touch,
pain, temperature, and pressure.
Immune Response: Langerhans cells in the skin detect and present
antigens to the immune system, initiating an immune response.
Pathogenesis of Skin Cancer
Three Main Types of Skin Cancer
Melanoma:
Characteristics: Arises from melanocytes (pigment-producing cells).
Signs and Symptoms: Asymmetrical moles, irregular borders, multiple
colors, diameter larger than 6mm, evolving shape/size.
Pathology: Malignant melanoma can invade deeper tissues and
metastasize.
,Risk Factors: UV exposure, fair skin, family history, many moles.
Treatment Options: Surgical excision, immunotherapy, targeted therapy,
chemotherapy.
Complications: High potential for metastasis, recurrence.
Comorbidity: May be associated with other skin conditions or immune
deficiencies.
Squamous Cell Carcinoma (SCC):
Characteristics: Arises from squamous cells (outer layer of skin).
Signs and Symptoms: Red, scaly patches, open sores, warts, crusted
surface, can bleed.
Pathology: Can grow rapidly and invade deeper tissues; less likely to
metastasize than melanoma.
Risk Factors: Chronic sun exposure, immunosuppression, HPV infection.
Treatment Options: Surgical excision, Mohs surgery, radiation therapy,
topical treatments.
Complications: Local tissue destruction, recurrence.
Comorbidity: Increased risk in immunocompromised individuals.
Basal Cell Carcinoma (BCC):
Characteristics: Arises from basal cells (bottom layer of the epidermis).
Signs and Symptoms: Pearly or waxy bump, flat flesh-colored or brown
scar-like lesion, bleeding or scabbing sore that heals and returns.
Pathology: Slow-growing, rarely metastasizes.
Risk Factors: UV exposure, fair skin, history of BCC, radiation exposure.
Treatment Options: Surgical excision, Mohs surgery, cryotherapy, topical
treatments.
, Complications: Local tissue destruction, recurrence.
Comorbidity: Can occur alongside other forms of skin cancer or chronic skin
conditions.
Bacterial, Viral, Fungal, and Vascular Disorders
Bacterial Infections:
Examples: Impetigo, cellulitis.
Symptoms: Redness, swelling, pain, pus formation.
Treatment: Antibiotics.
Viral Infections:
Examples: Herpes zoster (shingles), warts.
Symptoms: Blisters, itching, pain.
Treatment: Antiviral medications, symptomatic relief.
Fungal Infections:
Examples: Tinea infections (ringworm), candidiasis.
Symptoms: Itching, redness, scaling.
Treatment: Antifungal creams, oral medications.
Vascular Disorders:
Examples: Varicose veins, rosacea.
Symptoms: Swelling, redness, pain.
Treatment: Compression stockings, medications, surgery.
Genetic Disorders
The skin is the body's largest organ and serves as the first line of
defense against external threats. It protects you in several ways:
Barrier Function: The skin acts as a physical barrier that prevents
pathogens, chemicals, and physical abrasions from entering the body.
UV Protection: Melanin in the skin absorbs and dissipates ultraviolet
(UV) radiation, protecting deeper tissues from UV damage.
Temperature Regulation: Sweat glands and blood vessels in the skin help
regulate body temperature through sweating and
vasodilation/vasoconstriction.
Sensory Reception: The skin contains sensory receptors that detect touch,
pain, temperature, and pressure.
Immune Response: Langerhans cells in the skin detect and present
antigens to the immune system, initiating an immune response.
Pathogenesis of Skin Cancer
Three Main Types of Skin Cancer
Melanoma:
Characteristics: Arises from melanocytes (pigment-producing cells).
Signs and Symptoms: Asymmetrical moles, irregular borders, multiple
colors, diameter larger than 6mm, evolving shape/size.
Pathology: Malignant melanoma can invade deeper tissues and
metastasize.
,Risk Factors: UV exposure, fair skin, family history, many moles.
Treatment Options: Surgical excision, immunotherapy, targeted therapy,
chemotherapy.
Complications: High potential for metastasis, recurrence.
Comorbidity: May be associated with other skin conditions or immune
deficiencies.
Squamous Cell Carcinoma (SCC):
Characteristics: Arises from squamous cells (outer layer of skin).
Signs and Symptoms: Red, scaly patches, open sores, warts, crusted
surface, can bleed.
Pathology: Can grow rapidly and invade deeper tissues; less likely to
metastasize than melanoma.
Risk Factors: Chronic sun exposure, immunosuppression, HPV infection.
Treatment Options: Surgical excision, Mohs surgery, radiation therapy,
topical treatments.
Complications: Local tissue destruction, recurrence.
Comorbidity: Increased risk in immunocompromised individuals.
Basal Cell Carcinoma (BCC):
Characteristics: Arises from basal cells (bottom layer of the epidermis).
Signs and Symptoms: Pearly or waxy bump, flat flesh-colored or brown
scar-like lesion, bleeding or scabbing sore that heals and returns.
Pathology: Slow-growing, rarely metastasizes.
Risk Factors: UV exposure, fair skin, history of BCC, radiation exposure.
Treatment Options: Surgical excision, Mohs surgery, cryotherapy, topical
treatments.
, Complications: Local tissue destruction, recurrence.
Comorbidity: Can occur alongside other forms of skin cancer or chronic skin
conditions.
Bacterial, Viral, Fungal, and Vascular Disorders
Bacterial Infections:
Examples: Impetigo, cellulitis.
Symptoms: Redness, swelling, pain, pus formation.
Treatment: Antibiotics.
Viral Infections:
Examples: Herpes zoster (shingles), warts.
Symptoms: Blisters, itching, pain.
Treatment: Antiviral medications, symptomatic relief.
Fungal Infections:
Examples: Tinea infections (ringworm), candidiasis.
Symptoms: Itching, redness, scaling.
Treatment: Antifungal creams, oral medications.
Vascular Disorders:
Examples: Varicose veins, rosacea.
Symptoms: Swelling, redness, pain.
Treatment: Compression stockings, medications, surgery.
Genetic Disorders
