Neck restaging with sentinel node biopsy in T1-T2N0 oral and oropharyngeal cancer: Why and how?

Abstract

To evaluate the lack of accuracy in neck staging with the classical technique (i.e., neck dissection and routine histopathology) with the sentinel node (SN) biopsy in oral and oropharyngeal T1-T2N0 cancer. Cross-sectional study with planned data collection. Tertiary center care. In 50 consecutive patients, the pathological stage of sentinel node (pSN) was established after analyzing SN biopsies (n = 148) using serial sectioning and immunohistochemistry. Systematic selective neck dissection was performed. The pN stage was established with routine histopathologic analysis of both the non-SN (n = 1075) and the 148 SN biopsies. The sensitivity and negative predictive value of pSN staging were 100 percent. Conversely, if one considers pSN staging procedure as the reference test for micro- and macro-metastasis diagnosis, the sensitivity of the classical pN staging procedure was 50 percent (9/1; 95% CI 26.9-73.1) and its negative predictive value was 78 percent (95% CI 61.9-88.8). Fifteen patients (30%) were upstaged, including nine cases from pN0 to pSN >or= 1 and six cases from pN1 to pSN2. Two of the pN0-pSN1 upstaged patients died with relapsed neck disease. The SN biopsy technique appeared to be the best staging method in cN0 patients and provided evidence that routinely undiagnosed lymph node invasion may have clinical significance.