Colonic metastasis from breast carcinoma: A case report and systematic review of a rare clinical scenario

Purpose: Colonic metastasis from breast cancer is extremely rare, with an incidence of only 0.1%. Diagnosis is often difficult and guidelines are not yet established. The aim of our review is investigating the latency from the primary tumor, the common symptoms, the diagnostic and therapeutic strategies and the role of surgery for this rare clinical scenario. Materials: We report the case of a 57-year-old woman with multiple colonic metastasis from primary breast tumor, who underwent laparoscopic left hemicolectomy. A systematic review of 64 case reports was also conducted. Results: Lobular carcinoma is more frequently associated with gastro-intestinal (GI) metastasis than ductal carcinoma. The median age at diagnosis is 65.5 (IQR = 15) years with colonic metastases typically occurring after a median of 8 years (IQR = 13) from the primary tumor diagnosis. The most frequent symptoms are abdominal pain (34.4%), bowel habit changes (26.6%), and intestinal obstruction (9.4%). In 25% of cases, metastases were incidentally discovered during follow-up. The median disease-free survival was 12 months (IQR = 27.5). Thirteen studies reported death at a median of 12 months (IQR = 20), while 24 did not report follow-up data. Conclusions: The poor prognosis is mainly due to long latency between primary diagnosis and metastasis onset, as well as to non-specific symptoms. Immuno-histochemical is crucial for diagnosis, although not sufficient to determine tumor origin definitively. Patients with history of breast cancer presenting with GI symptoms should undergo prompt endoscopic evaluation, although routine surveillance remains controversial. Surgery may be considered in selected cases, but systemic therapies remain the cornerstone of treatment.