Gynecological Oncology – Endometrial Cancer Staging (FIGO 2009)

A 52-year-old postmenopausal woman presents with vaginal bleeding and a pelvic mass. Imaging reveals a 6 cm heterogeneous endometrial mass with invasion into the myometrium up to the inner half. Staging laparotomy with total abdominal hysterectomy, bilateral salpingo-oophorectomy, pelvic and para-aortic lymph node dissection is performed. Histopathology shows grade 2 endometrioid adenocarcinoma. Pelvic lymph nodes are negative, but one para-aortic node (1 of 15 sampled) shows micrometastasis. According to FIGO 2009 staging, what is the stage of this tumor?