December 20, 2023
Clark’s level is a system used in pathology reports to describe how far a skin cancer such as invasive squamous cell carcinoma or invasive melanoma has spread into the skin. It’s an important factor in determining the severity and potential behaviour of the tumour. The system consists of five levels, each indicating how deeply the tumour has penetrated through the layers of the skin:
Each increase in Clark’s level indicates a deeper penetration of the tumour and potentially a worse prognosis, as deeper tumours have a higher risk of metastasizing (spreading) to lymph nodes. However, it’s important to note that while Clark’s level provides valuable information about the depth of the tumour, other factors like the tumour thickness (which measures the actual depth of the invasion in millimetres) and the presence of ulceration are also critical for staging and prognosis. The combined assessment of these factors helps guide treatment decisions.