Histological Features
Under the microscope, SCC is characterized by the presence of atypical squamous cells that exhibit a range of differentiation. These cells often form nests or sheets and show features like increased nuclear-cytoplasmic ratio, pleomorphism, and hyperchromatic nuclei.
Keratin pearls and intercellular bridges are also common findings. The degree of differentiation can vary, with well-differentiated tumors showing more keratinization and poorly differentiated tumors exhibiting significant cellular atypia and mitotic activity.
Pathogenesis
The development of SCC is a multistep process involving genetic and environmental factors. Chronic exposure to UV radiation is a major risk factor, leading to DNA damage and mutations in key regulatory genes such as
p53. Other risk factors include exposure to chemical carcinogens, chronic inflammation, and certain viral infections like
human papillomavirus (HPV).
Clinical Presentation
SCC often presents as a rough, scaly patch, a persistent open sore, or a raised growth with a central depression. These lesions may bleed or develop a crust. In the case of mucosal involvement, symptoms can include difficulty swallowing, hoarseness, or a persistent cough, depending on the affected site. Diagnosis
The diagnosis of SCC is primarily based on histopathological examination. A biopsy is taken from the suspicious lesion and examined under a microscope. Immunohistochemical staining can aid in the diagnosis by highlighting specific markers such as
cytokeratins and
p63 that are typically expressed in squamous cells.
Treatment
Treatment options for SCC depend on the location, size, and extent of the tumor. Surgical excision is the most common treatment, often followed by
radiation therapy or
chemotherapy in more advanced cases. Early-stage tumors have a high cure rate, while advanced or metastatic SCC can be more challenging to treat.
Prognosis
The prognosis for SCC varies based on several factors, including the size and depth of the tumor, the presence of perineural invasion, and the patient's overall health. Early detection and treatment generally lead to a favorable outcome, while advanced stages may have a poorer prognosis.
Prevention
Preventive measures include minimizing exposure to UV radiation through the use of sunscreen, protective clothing, and avoiding tanning beds. Regular skin examinations and prompt attention to suspicious lesions can aid in early detection and treatment, reducing the risk of progression to invasive SCC.