Cost-utility of sentinel lymph node biopsy in cT1-T2N0 oral cancer

Objectives: To calculate the cost-utility of different strategies for the detection of occult lymph node metastases in cT1-T2N0 oral cancer.

Methods: A decision tree followed by a Markov model was designed to compare the cost-utility of the following strategies: (a) USgFNAC (ultrasound guided fine needle aspiration cytology), (b) SLNB (sentinel lymph node biopsy), (c) USgFNAC and, if negative, SLNB (d) END (elective neck dissection). Data was collected from 62 patients in four Dutch head and neck centres. Utilities were measured with the EQ5D questionnaire and resource use was recorded from patient charts. Costs were calculated from a hospital perspective. Uncertainty was explored with scenario analyses and probabilistic sensitivity analyses.

Results: With a 5- or 10-year time horizon, SLNB results in the highest number of additional quality-adjusted life years (QALYs, 0.12 and 0.26, respectively) for the smallest additional costs (€56 and €74, respectively) compared to USgFNAC. With a lifetime horizon END results in the highest number of additional QALYs (0.55) for an additional €1.626 per QALY gained compared to USgFNAC. When we make different assumptions regarding the duration of disutilities (≥5 years) or the improvement (≥3%) of sensitivity of SLNB, SLNB is the most favourable strategy from all time horizons.

Conclusion: SLNB is a good diagnostic strategy to evaluate cT1-T2N0 oral cancer. SLNB is the preferred strategy in a 5- or 10-year time horizon. From a lifetime horizon, END may be preferred. SLNB may become the optimal strategy from all time horizons if its sensitivity can be slightly improved.