What is Skin Cancer: Diagnosis and Treatment?

Learn how skin cancer is diagnosed and treated — from skin exams and biopsy to surgery, Mohs surgery, radiotherapy, and systemic therapies.

Cancer

Skin Cancer: Diagnosis and Treatment

2025-09-17

Overview

Skin cancer is usually confirmed with a biopsy after a suspicious spot is found.
Treatment depends on the type and stage — most cases are cured with surgery, but advanced melanomas may require immunotherapy or targeted drugs.

Skin Cancer by the Numbers

1 in 3 cancers diagnosed globally is a skin cancer (WHO).
>2 million non-melanoma cases (basal & squamous cell) diagnosed worldwide every year.
Melanoma makes up a minority of cases but causes the majority of skin cancer deaths.
90% of skin cancers are linked to UV exposure.
Surgery cure rates: >95% for basal and squamous cell cancers when caught early.
Melanoma survival: >95% if detected early, but <30% once spread to distant sites.

Key Points

Diagnosis relies on skin exams, dermoscopy, and biopsy.
Staging determines whether cancer has spread and guides treatment.
Surgery is the main treatment for most skin cancers.
Mohs surgery is highly effective for facial or recurrent cancers.
Radiotherapy and topical creams are used in selected cases.
Immunotherapy and targeted therapy are used for advanced melanoma.

Diagnosis

Skin Exam: Doctor checks for suspicious spots or moles.
Dermoscopy: Magnified light exam improves detection accuracy.
Biopsy: Excision, shave, or punch biopsy confirms diagnosis.
Staging Tests: Ultrasound, CT, MRI, or sentinel lymph node biopsy may be done if spread is suspected.

Treatment Options

1. Surgery

Excision: Standard removal of cancer with a safety margin.
Mohs Surgery: Layer-by-layer removal, examining each under a microscope, ideal for face or recurrent cancers.

2. Topical Therapy

5-FU or imiquimod creams may treat superficial cancers.

3. Radiotherapy

External beam radiation used when surgery isn’t feasible or for recurrence.

4. Systemic Therapy (Advanced Melanoma)

Immunotherapy: Checkpoint inhibitors (e.g., anti-PD-1 drugs).
Targeted Therapy: BRAF/MEK inhibitors if tumor has mutations.

FAQ

Q: How is skin cancer diagnosed?
A: Through a skin exam, dermoscopy, and confirmed by biopsy.

Q: What is Mohs surgery?
A: A surgical technique that removes cancer layer by layer, minimizing healthy tissue loss.

Q: When is radiotherapy used?
A: If surgery isn’t possible, or as additional treatment for advanced/recurrent cases.

Q: What treatments are used for melanoma?
A: Surgery for early stages, immunotherapy and targeted therapy for advanced disease.