Letrozole is a drug used in the treatment of postmenopausal women with breast and ovarian tumours. There is no evidence in the literature indicating its use in treating gastric cancer. We present a 68 year old lady admitted from the emergency department with weight loss, malaise and anaemia. Investigations confirmed the presence of two different primary tumours in the left breast and the stomach. Following that this patient with oestrogen receptor positive breast cancer and oestrogen receptor negative gastric cancer was treated with letrozole for her breast cancer followed by a gastric resection. Independent histology by two pathologists pre-operatively diagnosed gastric adenocarcinoma. Post-operatively, independent analysis of the resected stomach, omentum and lymph nodes revealed no evidence of gastric cancer. Therefore we conclude that there is a possibility of letrozole having an effect on gastric cancer. Further studies are needed.