Diagnosing melanoma involves several steps, starting with a physical examination and potentially leading to more advanced diagnostic tests. Here’s an overview of the diagnostic process:

1. Physical Examination

• Skin Check: The doctor performs a thorough examination of the skin to look for signs of melanoma. They will pay special attention to any moles, blemishes, or spots that have changed in appearance.
• Medical History: The doctor will inquire about the patient's personal and family history of skin cancer, as well as any history of sunburns or tanning bed use.

2. Dermatoscopy (Dermatoscopic Examination)

• Description: A dermatoscope, which is a handheld device with a magnifying lens and light source, is used to examine the skin more closely.
• Purpose: This helps in identifying specific patterns and structures in the skin that are not visible to the naked eye.

3. Biopsy

If the physical examination or dermatoscopy indicates that a lesion may be melanoma, a biopsy will be performed. There are several types of biopsies:

• Excisional Biopsy: The entire suspicious mole or growth is removed along with a small margin of surrounding healthy skin. This is the preferred method if melanoma is suspected.
• Incisional Biopsy: Only a portion of the suspicious area is removed. This method is used when the lesion is too large to be removed entirely.
• Punch Biopsy: A special tool is used to remove a small, circular section of the skin, including deeper layers.
• Shave Biopsy: A thin slice of the top layers of the skin is removed. This method is generally not recommended for suspected melanoma due to potential issues with accurate staging.

4. Pathology Examination

• Microscopic Examination: The biopsy sample is sent to a pathologist who examines it under a microscope to determine if the cells are cancerous. The pathologist will look for specific characteristics such as asymmetry, irregular borders, multiple colors, and depth of invasion.
• Histopathological Analysis: The depth of the tumor (Breslow thickness) and the level of skin involvement (Clark level) are assessed. The presence of ulceration and the rate of mitosis (cell division) are also evaluated.

5. Imaging Tests

If melanoma is diagnosed and there is a concern that it may have spread, additional imaging tests may be recommended:

• X-rays: Used to check for the spread of melanoma to the chest.
• CT (Computed Tomography) Scans: Provides detailed cross-sectional images of the body to detect metastasis.
• MRI (Magnetic Resonance Imaging): Particularly useful for detecting brain and spinal cord metastases.
• PET (Positron Emission Tomography) Scans: Detects areas of high metabolic activity, often indicative of cancer spread.
• Ultrasound: Sometimes used to examine lymph nodes near the primary melanoma site.

6. Sentinel Lymph Node Biopsy

• Description: A procedure to determine if melanoma has spread to the lymph nodes. A dye or radioactive substance is injected near the tumor site to identify the sentinel lymph nodes, which are the first nodes to which cancer cells are likely to spread.
• Procedure: These nodes are then surgically removed and examined for cancer cells.

Sources

• American Cancer Society
• Mayo Clinic
• National Cancer Institute

By following these steps, healthcare providers can accurately diagnose melanoma and determine the best course of treatment based on the stage and spread of the disease. Early detection through these diagnostic methods significantly improves the prognosis for melanoma patients.