Dysplasia and Carcinoma in Situ (Cervical)
Overview
Plain-Language Overview
Dysplasia and Carcinoma in Situ (Cervical) refers to abnormal changes in the cells on the surface of the cervix, which is part of the female reproductive system. These changes are not cancer but can be considered precancerous, meaning they have the potential to develop into cervical cancer if left untreated. The condition mainly affects the cervical epithelium, where cells grow abnormally and disorganized. It is often caused by persistent infection with high-risk types of human papillomavirus (HPV). Early stages usually do not cause symptoms, but if untreated, the abnormal cells can progress to invasive cancer, affecting a woman's health significantly. Regular screening helps detect these changes early, improving outcomes.
Clinical Definition
Dysplasia and Carcinoma in Situ (Cervical) is characterized by the presence of precancerous epithelial changes confined to the cervical mucosa without invasion beyond the basement membrane. It results primarily from persistent infection with high-risk oncogenic types of human papillomavirus (HPV), especially types 16 and 18, which induce disruption of cell cycle regulation via viral oncoproteins E6 and E7. These oncoproteins inactivate tumor suppressors p53 and Rb, leading to uncontrolled proliferation and accumulation of genetic mutations. The condition is classified histologically into low-grade and high-grade squamous intraepithelial lesions (LSIL and HSIL), with carcinoma in situ representing the most severe form of HSIL. It is clinically significant as a direct precursor to invasive cervical cancer, making early detection and treatment critical to prevent progression.