A Case of a Patient with Breast Invasive Lobular Carcinoma who Survived for 10 Years after Gastric Metastasis with Peritoneal Dissemination

Abstract

A 58-year-old woman had undergone right mastectomy and axillary lymph node dissection for right invasive lobular carcinoma 16 years previously. The pathological results were invasive lobular carcinoma, pT2N1(2/19)M0, pStage IIB, Estrogen Receptor-positive, Progesteron Receptor-positive, and HER2 score 1. Hormone therapy (anastrozole) was administered as a postoperative adjuvant therapy for four years. Six years after the surgery, her right lower abdominal pain appeared, and when appendicitis was suspected and appendectomy was performed, many disseminated nodules were found in her peritoneum. She was diagnosed with gastric metastasis and peritoneal dissemination of invasive lobular carcinoma and visited our hospital for therapy. She was administered tamoxifen and leuprorelin for nine years and three months, respectively, and anastrozole and palbociclib for seven months. The patient is still receiving treatment. Gastric metastasis and peritoneal dissemination of invasive lobular carcinoma often have a poor prognosis, and we report a rare case of a patient with long-term survival of ten years.