To the Editor: Adult granulosa cell tumor (AGCT) of the ovary is a low?grade malignant, sex cord?stromal tumor with an indolent course and late recurrence. Recurrences usually occur more than 5 years after the first treatment.[1] However, a few cases of aggressive AGCT have been reported.[2,3] We retrospectively reviewed all 213AGCT patients at Peking Union Medical College Hospital between 2000 and 2018 and identified six Stage I cases with recurrence <5 years. The Ethics Committee of Peking Union Medical College Hospital specifically approved this study (No. S?K413), and all included patients provided written informed consent to participate in the study.