Invasive Lobular Carcinoma of the Breast with Metastasis to the Colon

Abstract

Purpose: A 49-year-old woman was diagnosed with a 1.2 cm right breast mass in 2007. The patient elected against a biopsy at the time. In late 2009, she presented to GI office with a six week history of abdominal pain, weight loss, and hematochezia. Patient denied personal or family history of breast or colon cancer. A colonoscopy revealed a solitary 6 mm ulcer with a firm nodule in sigmoid colon. Histopathological findings were compatible with infiltrating carcinoma of the colon. MRI showed skeletal metastases in thoracolumbar spine and bilateral ribs, and a 1.4 cm lesion in the liver. CA15-3 was 371 U/ML and CA 27.29 was 124 U/ML. A PET scan revealed a 3.8 cm hyper-metabolic area in the right breast and bony metastases. Histological examination of breast biopsy showed for a low grade ER/PR positive and HER-2/neu negative invasive lobular carcinoma. She was diagnosed with colonic metastasis of invasive lobular carcinoma of the breast. A mastectomy was recommended, however the patient initially refused. A bilateral oophorectomy revealed invasive lobular carcinoma. Patient ultimately agreed to a modified radical right mastectomy in September 2010. The primary tumor was 5.5 cm in diameter, grade 6/9 with lymphovascular and perineural invasion. All surgical margins were negative. She had metastases to 10 out of 13 axillary lymph nodes. Patient had stage IV, T4 N3a M1 invasive lobular carcinoma of breast. She was treated with tamoxifen, radiation therapy, and monthly zolendronic acid. As of June 2011, PET continues to show stable osseous metastatic disease. Metastatic gastrointestinal tumors originating from Invasive lobular carcinoma (ILC) are unusual, and colonic metastases are especially rare. The clinical manifestations are variable and may range from non-specific complaints to acute GI symptoms. It is imperative to differentiate between metastatic breast cancer and primary colon cancer as treatment strategies differ. As seen in our case, careful correlation of both endoscopic histology and primary breast cancer histology was essential. Therefore, a high index of clinical suspicion with early endoscopy in those with vague symptoms and history of breast cancer is recommended.Figure: No Caption available.