Gastric and colon metastasis from breast cancer: case report, review of the literature, and possible underlying mechanisms.

Gastrointestinal metastases from breast cancer are not common. We present a 58-year-old female diagnosed with lobular breast cancer some years before whose relapses were gastric and colonic mucosal. Simultaneous metastases are extremely rare. To our knowledge, no cases of initial dual affectation have been reported. The patient also showed gastritis by Helicobacter pylori. Invasive lobular breast carcinoma is the most frequent special type of breast cancer and carries some specific molecular alterations such as loss of expression of E-cadherin. Although underlying mechanisms of metastasization are not entirely known, chemokines as well as inflammatory events seem to be implicated in this process. Interaction between chemokines and their receptors frequently induces cell migration. We hypothesize that H. pylori, inflammatory cells, and chemokines may create a favorable environment attracting tumor cells.