Gastric metastases from invasive lobular carcinoma of the breast: Case report

Invasive lobular carcinoma is the second most common type of invasive carcinoma of the breast. Although rare, invasive lobular carcinoma can lead to gastric metastases, which may appear several years after the initial diagnosis. The diagnosis is difficult, either because of its rarity or because of overlapping symptoms and imaging findings with primary gastric carcinoma. Immunohistochemistry is the key to diagnosis. We report a case of a 40-year-old woman with a previous history of invasive lobular carcinoma of the breast 2 years before, who presented recurrent and nonspecific gastrointestinal symptoms. Imaging findings revealed linitis plastica and the biopsy showed the presence of signet ring cell neoplasia. After gastrectomy, immunohistochemistry demonstrated diffuse expression of GATA-3 and the presence of estrogen receptors in some neoplastic cells with CK20(-), leading to the final diagnosis of gastric metastases from invasive lobular carcinoma of the breast.