Melanoma

Diagnosis

The diagnosis of melanoma can be made through the following techniques:

• Medical history and physical examination: The patients undergo a comprehensive evaluation of the signs and symptoms. The patients may be asked about the occurrence of the spot, its progression, alteration in color and size, and if the spot is bleeding. The patients may also be enquired about their history of any sunburn or tanning or if there is any family history of skin cancer. This information assists in determining the risk of melanoma in the patients. In addition, the patients are comprehensively checked for moles or new spots on the complete body that may indicate skin cancer. The patients may also undergo dermoscopy or surface microscopy to more clearly view the moles or spots.
• Ultrasound: Ultrasound is the imaging technique that uses sound waves to create clear images. The patients suspected of having melanoma may undergo an ultrasound to determine if cancer has spread to the nearby lymph nodes. Ultrasound does not use radiation and is safer than other imaging modalities. The technique may also be used to guide the needle to the abnormal cells for taking samples during biopsy (ultrasound-guided biopsy).
• Magnetic resonance imaging: Magnetic resonance imaging involves using powerful magnets and radio waves. The patients are recommended to undergo magnetic resonance imaging to determine if the melanoma has spread to other body parts, such as the brain and spinal cord.
• CT scan: CT scan provides a detailed, cross-sectional image of various body organs. It allows the oncologists to detect the spread of melanoma to other body parts, such as the liver or lungs. It also helps in detecting the spread of melanoma to lymph nodes. A CT scan is also performed to guide the needle to the abnormal cells during the biopsy.
• PET scan: PET scan is usually done during advanced melanoma. During this procedure, radioactive sugar is administered through the vessels. The sugar accumulates in the cells with high metabolic rates, such as cancer cells. A special camera is then used to determine the areas of sugar accumulation. PET scan helps detect the spread of melanoma to other body parts or lymph nodes.
• Chest radiograph: The patients may also undergo chest radiography to determine the spread of melanoma to the organs of the thoracic cavity, such as the lungs.
• Biopsy: Biopsy is the only confirmatory test for melanoma. This test involves obtaining a sample of the abnormal cells and testing it under the microscope to determine the presence of cancer cells. Some of the methods for performing a biopsy are:
• Punch biopsy: This procedure is done through a special tool that obtains a deeper skin sample. Once the sample is removed, the skin edges are stitched.
• Shave biopsy: This technique uses a small surgical blade to remove the upper layers of the skin. The procedure is usually used in patients with less risk of melanoma as it does not remove samples from the deeper skin.
• Incisional and excisional biopsy: Incision biopsy removes only a small tumor section. An excisional biopsy involves cutting the entire tumor and surrounding healthy tissues.
• Biopsy in metastatic melanoma: Patients may also undergo biopsies if the melanoma is suspected of having spread to other body parts and is potentially confirmed by the imaging modalities. The biopsy can be done through fine needle aspiration technique (use of a hollow, thin needle to obtain tissue sample) or surgery. The lymph node may also be removed to determine the extent of cancer spread.