A 52-year-old woman from Mumbai underwent exploratory laparotomy for a suspected ovarian mass. Intraoperative findings revealed a 6 cm left ovarian tumor with rupture of the capsule, ascites (200 mL), and involvement of the omentum. Frozen section confirmed high-grade serous adenocarcinoma. The surgeon performed total abdominal hysterectomy, bilateral salpingo-oophorectomy, omentectomy, and peritoneal biopsies. Postoperatively, she is staged as IIIC. Which of the following is the most appropriate next step in management?