Basal Cell Carcinoma
Basal cell carcinoma is by far the most common cutaneous malignancy. Basal cell carcinoma is a tumor that grows slowly and rarely metastasizes. BCC is more common among males living in geographic locations with greater UV exposure. Furthermore, previous history of SCC or BCC is the most common predictor of BCC development.
Etiology:
It is believed that BCC originates from pluripotent cells in the basal layer of the epidermis or the pilosebaceous unit. This might explain the rare occurrence of BCC in the hand despite it being a frequently sun exposed area. As the dorsum of the hand lacks the presence of sebaceous structures.
Moreover, it is well-established that the single most important risk factor for developing BCC is UV light exposure –particularly UVB light. Lighter skin phototypes, ionizing radiation exposure, immunosuppression, and genetic predisposition are all associated with increased risk of BCC.
Clinical Features:
BCC presents as a slowly growing skin colored/pink plaque or nodule, that could bleed or ulcerate spontaneously. Occasionally BCC could metastasise to lymph nodes.
BCC subtypes:
1.Nodular BCC:
It presents as a pearly nodule with a smooth surface, rolled edges, and may have central depression, ulceration, and telangiectasia . Cystic variant is soft, with jelly-like consistency.
2. Superficial BCC:
It presents as a scaly, irregular plaque with thin rolled edges. It may present with multiple micro-erosions.
3.Morphoeic BCC:
It presents as a waxy, scar-like plaque with irregular borders. It may present with deep extensions, sometimes infiltrating cutaneous nerves.
4. Basosquamous carcinoma:
It is a mix between basal cell carcinoma (BCC) and squamous cell carcinoma (SCC). it has an infiltrative growth pattern and could potentially be more aggressive than other subtypes of BCC
5. Pigmented BCC:
The rarest type of BCC, which comprises 6% of total BCC. This type can occasionally mimic melanoma.
Diagnosis and Treatment:
A histological diagnosis of BCC is a must, either through a biopsy or following excision. Furthermore, there are multiple treatment modalities used for BCC, which include both surgical and non-surgical therapies. Surgical treatment include: excision biopsy, mohs micrographically controlled excision, and superficial skin surgery. Non-surgical modalities include: cryotherapy, Imiquimod cream, radiotherapy, photodynamic therapy and Fluorouracil cream.
Written by: Rema Aldihan, medical student.
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