OBJECTIVES: Surgery is a standard modality in the modern management of solid tumors. Unfortunately, some patients will experience unplanned readmissions and ED visits following their operation. Emerging trends in health reform have introduced new financial detriments to hospital reencounters in addition to the negative impact on quality of care.  Our objective was to develop an electronic approach to assessing unplanned hospital reencounters following common cancer operations in order to guide decision-making aimed improving value in our patient population. METHODS: The target population for this study was adult cancer patients undergoing mastectomy and colectomy operations for cancer. Data were abstracted using an Electronic Data Warehouse (EDW) to determine 30-day emergency department visits and hospital readmissions following the selected cancer operations.  The secondary outcome measure was cost of care for patients returning to the hospital within 30-days.   RESULTS: Among 105 patients undergoing selected breast and colon cancer operations from January 1, 2012 to December 31, 2012 the hospital reencounter rate was 11.9%.  Wound-related complications were responsible for 73% of these hospital reencounters. Total costs (direct and indirect) for hospital reencounters were $210,722.76. CONCLUSIONS: Unplanned hospital readmissions and emergency department visits following cancer surgery largely result from post-operative complications. These unplanned reencounters are a costly source of poor quality care. Patient-centered, disease-specific efforts to reduce unplanned hospital reencounters have the potential to significantly increase quality while decreasing costs. Using data for decision-making in quality improvement is important for achieving value in patient care.