[1177] Sentinel Lymph Node Strategy with Serial Sections with Immunochemistry in T1T2N0 Oral and Oropharyngeal Cancers Leads to 30% Upstaged Patients.

Valerie Costes, Vincent Burcia, Jean Luc Faillie, Michel Zanca, Renaud Garrel. Gui de Chauliac Hospital, Montpellier University Hospital Center, France; Arnaud de Villeneuve Hospital, Montpellier University Hospital Center, France

Background: The aim of this study was 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.
Design: Cross-sectional study with planned data collection was used. In 50 consecutive patients, the pathological stage of sentinel node (pSN) was established after analyzing SN biopsies (n = 148) using serial sectioning (5 microns thick sections every 250 microns) and immunohistochemistry with AE1/AE3. 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.
Results: 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). Nine pN0 patients were pSN positive.

comparison of pN and pSN staging method

	pN+	pN0	total
pSN+	9 (18%)	9 (18%)	18 (36%)
pSN0	0	32 (64%)	32 (34%)
total	9 (18%)	37 (74%)	50 (100%)

table 1

Fifteen patients (30%) were upstaged, including nine cases from pN0 to pSN1 (4) or pSN2b (5) and six cases from pN1 to pSN2. Two of the pN0-pSN1 upstaged patients died with relapsed neck disease.
Conclusions: The SN biopsy technique with serial sections with immunochemistry appeared to be the best staging method in cN0 patients and provided evidence that routinely undiagnosed lymph node invasion may have clinical significance.
Category: Head & Neck

Tuesday, March 1, 2011 11:30 AM

Platform Session: Section G, Tuesday Morning