One of the key features of squamous cell carcinoma is the presence of:

The key feature of squamous cell carcinoma is indeed the presence of scaly red papules and nodules. This type of skin cancer originates from the squamous cells, which are flat cells found in the outer layer of the skin. The appearance of these lesions often includes rough, scaly patches or nodules that can be red or crusty. Such lesions may bleed or develop into open wounds and can vary in size.

In contrast to the characteristics of squamous cell carcinoma, fluid-filled cysts typically relate to other conditions, such as sebaceous cysts or epidermoid cysts, rather than a malignant state. Abscess formation usually points to an infection rather than a direct indication of cancer. Hyperpigmented lesions could denote different skin issues, including benign moles or melanoma, but they are not specifically indicative of squamous cell carcinoma. Thus, the typical clinical presentation of scaly red papules and nodules is a hallmark feature that helps in identifying this type of skin cancer.