Sentinel node biopsy versus elective neck dissection. Which is more cost-effective? A prospective observational study

Abstract

Objective

The aim of this prospective not randomized observational study was to determine the costs and outcomes of sentinel lymph node biopsy (SNB) vs elective neck dissection (END) among patients with early oral squamous cell carcinoma (OSCC).

Materials and methods

Seventy-three consecutive patients were divided according to neck staging method. Patients took the decision themselves after receiving detailed information of both suggested treatment tools. False negative (FN) and negative predictive value (NPV) were assessed. Log-rank test was used to compare disease-free survival (DFS) and overall survival (OS). Only direct costs were analysed. Cost information derived from volumes for hospital stay, surgery and neck outcome were obtained from an internal database of tertiary health care center.

Results

Thirty-two patients underwent SNB and 41 underwent an END (levels I–III). Average follow-up time was 48.2 months (range 7–80). Five neck recurrences were recorded in the SNB group (range 11–21). Seven neck recurrences occurred in the END group (range 9–16). No significant differences were found in DFS or OS. True negative patients in SNB group incurred in 42% less costs than END group. FN regardless of radiotherapy, was also lower in the SNB group. However, pN+ patients generated 23% more costs in the SNB group.

Conclusion

In this not randomized observational study with an average follow-up period of 48.2 months, SNB appear to confer less cost than END, with similar prognosis.

Introduction

The oral cavity is one of the most common locations of head and neck primary malignancies. Of those, 90% are squamous cell carcinomas (Capote et al., 2007). The most important independent prognostic factor for this type of tumour is the presence of metastasis in the cervical lymph nodes. Survival is reduced by 50% when there are neck metastases, thus adequately diagnosing and treating the neck is of great importance (Sloan, 2009). In locally advanced disease (T3–T4) or in presence of positive lymph nodes (N+), neck dissection is the elective treatment for initial management of the neck (Omura, 2014). However, controversy exists in literature as to early stages (I–II), with clinically negative neck. The risk of occult metastasis during these stages is of 15–25%, which means that 75–85% of the patients could be receiving an unnecessary neck dissection ( Melkane et al., 2012, Thompson et al., 2013, D'Cruz et al., 2015). Sentinel node biopsy (SNB) is nowadays considered as an alternative to elective neck dissection (END) for cervical staging in oral squamous cell carcinoma (OSCC) in stages I–II (Ross et al., 2002, Kuriakose and Trivedi, 2009, Civantos et al., 2010, Broglie et al., 2011). American and European multicentre studies have shown SNB to have a high accuracy for detecting occult cervical metastases (Alkureishi et al., 2010, Civantos et al., 2010). Identification indexes for sentinel nodes (SN) in OSCC are comparable with other diseases (melanoma and breast cancer), where the SNB is a routine procedure (Morton et al., 2005, Zavagno et al., 2008).

Currently, few studies have researched about the economic impact of clinical use of the SNB in OSCC (Govers et al., 2013, O'Connor et al., 2013). O'Connor et al. (2013) conducted a study with patients taking part in the European Sentinel Node Biopsy Trial Protocol (SENT trial) and their results suggested that SNB is cheaper than the traditional neck treatment.

The present study had two objectives: to analyse oncologic safety by comparing neck disease control and survival rates and to assess the relative cost of both staging procedures in early OSCC.