Comprehensive cost analysis of sentinel node biopsy in solid head and neck tumors using a time-driven activity-based costing approach

Head and neck cancer (HNC) is predominantly a locoregional disease. Sentinel lymph node (SLN) biopsy offers a minimally invasive means of accurately staging the neck. Value in healthcare is determined by both outcomes and the costs associated with achieving them. Time-driven activity-based costing (TDABC) may offer more precise estimates of the true cost. Process maps were developed for nuclear medicine, operating room and pathology care phases. TDABC estimates the costs by combining information about the process with the unit cost of each resource used. Resource utilization is based on observation of care and staff interviews. Unit costs are calculated as a capacity cost rate, measured as a Euros/min (2014), for each resource consumed. Multiplying together the unit costs and resource quantities and summing across all resources used will produce the average cost for each phase of care. Three time equations with six different scenarios were modeled based on the type of camera, the number of SLN and the type of staining used. Total times for different SLN scenarios vary between 284 and 307 min, respectively, with a total cost between 2794 and 3541€. The unit costs vary between 788€/h for the intraoperative evaluation with a gamma-probe and 889€/h for a preoperative imaging with a SPECT/CT. The unit costs for the lymphadenectomy and the pathological examination are, respectively, 560 and 713€/h. A 10 % increase of time per individual activity generates only 1 % change in the total cost. TDABC evaluates the cost of SLN in HNC. The total costs across all phases which varied between 2761 and 3744€ per standard case.