Las Vegas--Metastatic breast cancer patients experience significantly more complications and mortality within 30 days of surgical treatment for their disease than patients with earlier stage cancer, according to a new study.  Lead researcher Erin Cordeiro, MD of the University of Toronto reported this week at the American Society of Breast Surgeons (ASBrS) Annual Meeting that for metastatic patients, the 30-day morbidity was 7.5% and mortality was 1.54%, while the non-metastatic group experienced 3.7% morbidity and 1.8% mortality.   She noted that common post-operative problems in the metastatic setting included infectious, respiratory, thrombolic, cardiac and bleeding complications. The adjusted odds ratio of post-operative complications for metastatic disease was 1.6.    “These results are important,” says Dr. Cordeiro.  “We found that breast surgery in stage 4 patients is occurring frequently in North America.  Research on the survival benefits for breast surgery in metastatic patients has had conflicting results.  But whether these patients are at higher risk of post-operative complications has never been examined.  A patient with metastatic breast cancer likely has systemic changes that predispose them to other medical difficulties.”   The study analyzed National Surgical Quality Improvement Program (NSQIP) participant use files (PUF), a prospectively collected database of 30-day inpatient and outpatient morbidity and mortality.   From 2005 to 2012, 68,316 patients were identified who underwent surgical treatment for breast cancer.  Of these, 1031 or 1.5% had diagnosed metastatic cancer.   Patients undergoing bilateral breast surgery, and those with concurrent surgery that was not breast- and/or reconstruction-related were excluded. The study controlled for types of surgery performed, including axillary lymph node dissection and mastectomy.  It also controlled for associated co-morbidity, age, diabetes, smoking status, BMI, pre-operative chemo or radiation therapy and operative time.   Of the metastatic group, 71% underwent mastectomy, while 49% received the surgery in the non-metastatic group.  Metastatic patients were also more likely to receive full axillary lymph node dissection.  They had a longer median time in surgery and longer post-operative hospital stay.  “Research on the survival benefits of breast cancer surgery for metastatic patients is currently underway,” comments Dr. Cordeiro.  “But until those findings are clear, this study shows that the risks of surgery are something to seriously consider before deciding on a course of treatment.”