SKIN CANCER SCREENING
MELANOMA
Melanoma is a potentially serious type of skin cancer, where there is uncontrolled growth of melanocytes, or pigment cells. It is the result of an uncontrolled proliferation of melanocytic stem cells that have went through a genetic transformation. It can show up anywhere on the skin either from an existing mole or as a “new” growth.
Superficial forms of melanoma usually spread out within the epidermis (in situ), which are reported as radial or horizontal growth phase. With further genetic changes, an invasive melanoma occurs when there is a tumour that invades into the surrounding dermis through the basement membrane.
Once the melanoma cells have reached the skin’s dermis layer, it spreads to other tissues through the lymphatic system to local lymph nodes or through the blood stream to other organs in the body such as the brain or lungs. This is known as a metastatic disease. Chances of this happening depend on how deep the cells have penetrated the skin. Typically, melanoma can be first spotted when there is a change in its shape, colour, and size within an existing mole. However, melanoma may also appear as a new mole. People should consult their doctor for any visible changes on the skin. Diagnosing melanoma involves the removal of tissue to check for cancer cells.
THE ABCDEs of Melanoma:
Going for a skin cancer screening in Singapore enables early detection which is imperative in the treatment of Melanomas. Patients should look for the following while examining irregularities:
- –Asymmetry: When one side of the mole’s shape does not match up to the other half.
- –Border Irregularity: When edges are blurred in its outline, or when ragged or notched. This pigment can spread into the surrounding skin.
- –Colour Irregularities: Different shades of black, brown and tan, with areas of gray, white, red or blue present.
- –Diameter: Typically, there is an increase in size. Melanomas are small, but most can be bigger than the size of a pea (larger than 6 mm).
- –Evolving: The mole’s shape, size or colour has altered over time. This includes symptoms such as bleeding, pain or itch as well.
Melanomas have varying appearances, with many presenting all of the ABCDE signs. Some might have changes or abnormal areas that can only be found in one of two ABCDE features. In advanced cases, the mole texture may change. For example, the surface skin may break down and look scraped. It may also turn out to be hard or lumpy, and the surface may ooze or bleed. Sometimes, melanoma is tender, painful or itchy.
SKIN CANCERS (NON-MELANOMA)
NON-MELANOMA SKIN CANCERS (BCC, SCC AND SCC-IN-SITU)
There are different types of skin tumours/growths that you should check for. While some are harmless and require no treatment, some are cancerous and should be detected and removed early. Some common malignant skin tumours are non-melanoma skin cancers. These skin cancers include squamous cell carcinoma (SCC) and basal cell carcinoma (BCC).
BASAL CELL CARCINOMA (BCC)
BCC is one of the most common types of skin cancer, which develops gradually and can be painless during the earlier stage. Typically occurring as a persistent ulcer with a pearly raised margin (known as a rodent’s ulcer), BCC often appears pigmented in Asians and non-pigmented in fairer skin types. They commonly develop over sun-exposed areas of the skin such as the face and upper limbs. If left treated, this locally invasive cancer can slowly erode into surrounding skin and underlying structures such as muscle and bone.
One predisposing factor is chronic sun exposure, and increased risk has also been associated with chronic arsenic exposure. The tumour rarely metastasizes to regional lymph nodes or distant organs but causes morbidity by local tissue destruction and may lead to subsequent disfigurement or functional impairment.
SQUAMOUS CELL CARCINOMA-IN-SITU (BOWEN’S DISEASE)
This is a very early form of skin cancer that is easily treatable (i.e. early form of SCC), where the malignant cells are only located within the upper layer (epidermis) of the skin and has not yet spread into the deeper dermal layer. It typically presents as a scaly raised red plaque, which does not respond to treatment.
SQUAMOUS CELL CARCINOMA (SCC)
Squamous Cell Carcinomas are malignant skin tumours of the keratinizing cells of the epidermis or its appendages, and also that of mucous membranes with squamous epithelium. It is more aggressive than BCC and on top of local tissue destruction, and perineural and vascular involvement; SCC has a risk of spread to regional lymph nodes and distant metastasis.
Typically developing as an irregular fleshy growth over sun-exposed skin, SCC growths increase in size, giving rise to a lump, which may break down to form an ulcer in some cases. Chronic sun exposure is an important contributing factor as well as chronic arsenic exposure. Other risk factors include chronic immunosuppression (e.g. organ transplant patients and patients on immunosuppressive medications), in addition to chronic non-healing wounds and ulcers.
SUSPECTING SKIN CANCER? HERE’S WHAT YOU SHOULD DO:
A biopsy should be done to confirm the diagnosis and type of cancer. Treatment options in Singapore depend on the histological subtype, location, size and patient preference as well as co-morbidities. Options include wide excision, Mohs micrographic surgery, cryotherapy, topical therapy, photodynamic therapy and radiotherapy.
