Statement: the intervention in the primary clinical trial involves taking a single drug orally, whereas the intervention in the secondary clinical trial is a medical procedure.
Primary_evidence: INTERVENTION 1:    Letrozole   Participants received 2.5 milligram (mg) of Letrozole tablets orally once daily (QD) for a period of 24 weeks.
Secondary_evidence: INTERVENTION 1:    Sentinel Lymph Node Biopsy [Not Specified]