FIGO Stage IA1

**Semantic type:** Classification

**Definition:** A FIGO stage term that applies to gynecologic cancers. For cervical cancer, it refers to invasive cancer that is diagnosed microscopically only. The stromal invasion has a maximum depth of 3.00 mm and a horizontal spread of 7.00 mm or less; there is no FIGO stage IA1 for endometrial cancer.

**Synonyms:** - Stage IA1