Final answer:
Clinically, skin tumors are classified by performing a biopsy, which allows pathologists to classify the tumors into main types like basal cell carcinoma, squamous cell carcinoma, and melanoma. These types are defined by their origin in the skin's layers, and melanoma is particularly dangerous due to its high metastatic potential. Skin tumors are also staged based on size and spread.
Step-by-step explanation:
To classify skin tumors clinically, a biopsy is typically required. This procedure involves taking a tissue sample from the tumor and examining it microscopically by a pathologist. Skin cancers are generally classified by the cell type from which they originate. The three common types of skin cancer are: basal cell carcinoma, squamous cell carcinoma, and melanoma.
Basal cell carcinoma and squamous cell carcinoma begin in the epidermis, while melanoma is characterized by the uncontrolled growth of melanocytes, the pigment-producing cells. Melanoma is particularly notable as it develops typically from a mole and can be highly metastatic, making it the most fatal form of skin cancer. These cancers are also staged based on factors like tumor size and the extent to which the cancer has spread.
An important aspect of clinical classification involves differentiating between benign growths like moles and potential skin cancers. Features to look out for include asymmetry, irregular borders, dark coloration, and a diameter larger than typical moles—summarized by the mnemonic ABCD.