Double Primary Cancer: Breast Cancer and Gastric Cancer

Introduction: Breast carcinoma is the most prevalent malignancy and the second leading cause of cancer death in women, while multiple primaries are conditions where there is more than one synchronous or metachronous cancer in one individual. Double primary between breast carcinoma and colon cancer is a primary tumor with a high incidence, while breast carcinoma metastasis to the colon is a rare entity except for lobular histotype breast carcinoma. In this case report, a woman with double primary breast cancer is reported. Case Report: A 50-year-old woman came with complaints pain of the entire abdomen since 2 days before go to hospital, worsening when starting to eat, accompanied by nausea. The patient had a history of modified radical mastectomy (MRM) for indications of right breast carcinoma cT3N0M0. In addition, a history of ovarian carcinoma that had undergone chemotherapy was also found. On esophagogastroduodenoscopy examination, a gastric mass was found with ulceration and necrosis and a biopsy showed high-grade neuroendocrine carcinoma and adenocarcinoma. Conclusion: Breast malignancy can be invasive or non-invasive and can undergo metastasis. In addition to metastasis, cancer can also appear in two different places but histologically or morphologically different. This condition is called multiple primaries due to host, lifestyle, and environmental factors.