Abstract
A 72-year-old woman exhibiting lumbar pain and loss of appetite was admitted to our hospital. Deformity of the left breast was noted, and she was referred to our department. From the first examination, we observed severe anemia and DIC. Needle biopsy of the breast revealed invasive lobular carcinoma of the breast, including signet ring cell cancer presenting with an Indian file pattern. Gastroendoscopy showed varioliform erosion, and FDG-PET showed diffuse accumulation in the central bony skeleton, while biopsies of the stomach and bone marrow showed signal ring cell cancer.
Immunostaining of biopsy tissue from the stomach yielded positive results for ER and MUC1, which is positive in mammary gland mucus, but negative results for MUC5AC, which is positive in stomach mucus. The gastric lesion was therefore diagnosed as a metastasis from the invasive lobular carcinoma of the breast. However, the patient died at about 1 month from onset, about 2 weeks after the first visit. We report herein our experience with invasive lobular carcinoma of the breast accompanied by disseminated bone marrow carcinomatosis and stomach metastasis due to signet ring cell cancer, which culminated in the rapid outcome.
