UCSF

In March 2012, the College of American Pathologists and American Society for Colposcopy and Cervical Pathology, in collaboration with 35 stakeholder organizations, convened a consensus conference called the Lower Anogenital Squamous Terminology (LAST) Project. The recommendations of this project include using a uniform, two-tiered terminology to describe the histology of human papillomavirus-associated squamous disease across all anogenital tract tissues: vulva, vagina, cervix, penis, perianus, and anus. The recommended terminology is "low-grade" or "high-grade squamous intraepithelial lesion (SIL)." This terminology is familiar to clinicians, because it parallels the terminology of the Bethesda System cytologic reports. Biopsy results using SIL terminology may be further qualified using "intraepithelial neoplasia" (IN) terminology in parentheses. Laboratory p16 tissue immunostaining is recommended to better classify histopathology lesions that morphologically would earlier have been diagnosed as IN 2. p16 is also recommended for differentiating between high-grade squamous intraepithelial lesions and benign mimics. The LAST Project recommendations potentially affect the application of current guidelines for managing cervical squamous intraepithelial lesions. The authors offer interim guidance for managing cervical lesions diagnosed using this new terminology with special attention paid to managing young women with cervical high-grade squamous intraepithelial lesions on biopsy. Clinicians should be aware of the LAST Project recommendations, which include important changes from prior terminology.