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Context: Study of Pembrolizumab (MK-3475) in Combination With Adjuvant Chemotherapy With or Without Radiotherapy in Participants With Newly Diagnosed Stage-IV Endometrial Cancer After Surgery With Curative Intent (MK-3475-B21 / KEYNOTE-B21 / ENGOT-en11 / GOG-3053). A Phase 3, Randomized, Double-Blind Study of Pembrolizumab Versus Placebo in Combination With Adjuvant Chemotherapy With or Without Radiotherapy for the Treatment of Newly Diagnosed High-Risk Endometrial Cancer After Surgery With Curative Intent (KEYNOTE-B21 / ENGOT-en11 / GOG-3053). Experimental: Pembrolizumab + Chemotherapy. Placebo Comparator: Placebo + Chemotherapy

Question: list the intervention combinations in a numbered list

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Helpful answer: Provide two versions of response separated with exactly 6 asterisk symbols: ******.
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