Abstract
Appendiceal tumors are rare and are most commonly diagnosed incidentally during surgical removal of the appendix for acute appendicitis. Appendiceal adenocarcinomas are the most common appendiceal cancers, and their metastasis to the breast is extremely uncommon. We report a case of mucinous appendiceal adenocarcinoma presenting with breast metastasis. To the best of our knowledge, there has been only one case published in the literature about appendiceal cancer with metastasis to the breast. Interestingly, our patient's initial presentation was palpable breast masses rather than gastrointestinal symptoms.