19. Non-melanoma skin cancer
Basal cell carcinoma
- Epidemiology
- Technically the most common cancer, but it is often excluded from data due to its low mortality and morbidity
- BCC accounts for 75% of all skin cancer
- Most common skin cancer
- Pathology
- Hedgehog pathway is often mutated
- Almost never metastasises, leading to low mortality and morbidity
- May cause local destruction, which may be severe if located on the face
- Types
- Nodular BCC
- Superficial BCC
- Morpheaform BCC
- Naevoid basal cell carcinoma syndrome
- Autosomal dominant disease
- Multiple BCC in young age
- Bone and neurological malformations
- +++
- Risk factors
- Chronic sun exposure
- Old age
- Skin types I and II
- Clinical features
- Pearly papule or nodule
- Rolled border
- Central crater of ulceration
- On sun-exposed skin
- Usually upper lip/nose area
- Slow growing
- Types
- Nodular BCC
- Superficial BCC
- On trunk
- Flat plaque lesion
- Nevoid basal cell carcinoma syndrome
- Prognosis
- Virtually never metastasizes
- Locally aggressive
- Diagnosis
- Clinical, based on typical symptoms
- Definite (histological) diagnoses often made after surgical excision of suspected lesion
- Full-thickness biopsy -> histology
- Treatment
- Surgery
- Surgical excision with 5 mm safety border
- Primary treatment is almost all cases
- Radiotherapy
- If surgery is not an option
- Chemotherapy
- Alternatives for superficial and small BCCs
- Cryosurgery
- Photodynamic therapy
- Laser ablation
- Topical chemotherapy
- Topical imiquimod
- Targeted therapy
- Vismodegib or sonidegib
- Hedgehog pathway inhibitors
- For metastatic BCC or BCC which recurs after surgery
- Follow-up
- Physical examination at 3, 6, 12 months
- Sun protection
Squamous cell carcinoma
Merkel cell carcinoma
- Non-melanoma skin cancer related to immune system dysfunction
- Higher incidence and worse prognosis in immunocompromised
- Due to Merkel cell polyomavirus
- Pinkish nodule on sun-exposed areas
- Treatment is surgical excision
Dermatofibrosarcoma protuberans
- Rare tumour, but the most common cutaneous sarcoma
- Translocation between chromosome 17 and 22
- Treatment is surgical excision
Kaposi sarcoma
- Caused by HHV8, immunosuppression is risk factor
- Malignant tumor of endothelial cells
- 4 types
- Classic – in older males
- Endemic – in Africa
- Immunosuppressive therapy-related
- AIDS-related
- Clinical features
- Multiple cutaneous lesions
- Purplish macules -> patches -> papules -> plaques -> nodules
- Rapidly growing
- Initially seen on face, oral cavity or chest
- Organs can be involved
- Treatment
- Classic KS -> surgery or radiotherapy
- HIV-related KS -> treatment of AIDS alone may cause cancer regression
- KS associated with non-HIV immunosuppression -> changing immunosuppressing drug alone may cause regression