Head and Neck Cancer
PD 10 - H&N 2 - Head and Neck Poster Discussion
1088 - Postoperative Staging of the Neck Dissection Using Extracapsular Spread and Lymph Node Ratio As Prognostic Factors in HPV-Negative Head and Neck Squamous Cell Carcinoma Patients (HNSCC)
Tuesday, October 23
1:42 PM - 1:48 PM
Location: Room 217 A/B
Postoperative Staging of the Neck Dissection Using Extracapsular Spread and Lymph Node Ratio As Prognostic Factors in HPV-Negative Head and Neck Squamous Cell Carcinoma Patients (HNSCC)
K. Majercakova, C. Valero, M. López, J. García, N. Farré, M. Quer, J. Craven-Bartle, and X. León; Hospital de la Santa Creu i Sant Pau, Barcelona, Spain
Purpose/Objective(s): The purpose of this study was to assess the prognostic capacity of the presence of nodes with extracapsular spread (ECS) and the lymph node ratio (LNR, ratio between positive nodes and total number of removed nodes) in HPV negative HNSCC patients treated with neck dissection and to compare it with the 8th edition of the TNM/AJCC classification.
Materials/Methods: A retrospective study of 1383 patients with HPV negative HNSCC (oral cavity 22.8%, oropharynx 18.1%, hypopharynx 15.5% or larynx 43.6%) treated with a neck dissection between 1985 and 2013 was carried out. The distribution of the patients regarding to TNM was: T1 175 (12.7%), T2 400 (28.9%), T3 519 (37.5%), T4 289 (20.9%) for local extension and N0 609 (44.0%), N1 258 (18.7%), N2 411 (29.7%), N3 105 (7.6%) for regional extension. The mean follow-up was 5.7 years. The majority of patients (94%) were moderate-severe smokers. 2140 neck dissections (469 radical and 1671 selective) were performed. The mean number of lymph nodes (LN) studied per patient was 31.2 (SD 19.0, range 7–118). A classification of the patients was developed according to the presence of nodes with ECS and the LNR value with a recursive partitioning analysis (RPA) model. The obtained and 8th edition of the TNM/AJCC classification were compared using hazard discrimination (HD), a parameter measuring the prognostic quality of a classification. HD ranges from 0 to 1, where 1 represents an ideal classification.
Results: Five-year disease-specific survival for all patients was 63.6%. 677 patients (49.0%) were pN0, 356 (25.7%) had LN without extracapsular spread (pN+/ECS−) and 350 (25.3%) had LN with extracapsular spread (pN+/ECS+). Five-year disease specific survival related to the presence of LN metastases with ECS was: 83.0% for pN0, 62.3% for pN+/ECS−, and 25.7% for pN+/ECS+ patients (p=0.0001). Five-year disease-specific survival according to the 8th edition of the TNM/AJCC classification was: pN0 83.0%, pN1 69.1%, pN2 57.0% and pN3 22.2% (p=0.0001). The RPA defined a classification tree with 4 terminal nodes: for patients without ECS (including patients pN0) the cut-off point for LNR was 1.6% and for patients with LN with ECS was 11.4%. Five-year disease-specific survival for patients without ECS and LNR<1.6% was 83.3%; without ECS and LNR≥1.6% was 61.5%; with ECS and LNR<11.4% was 33.7%; and for patients with ECS and LNR≥11.4% was 18.5%. The classification obtained with the RPA had better discrimination between categories than the 8th edition of the TNM/AJCC classification (HD 0.868 versus 0.653, respectively).
Conclusion: The ECS status and the LNR value proved high prognostic capacity in the pathological evaluation of the neck dissection. The combination of ECS and LNR improved the predictive capacity of the 8th edition of the TNM/AJCC classification in HPV-negative HNSCC patients.
Author Disclosure: K. Majercakova: None. C. Valero: None. J. García: None. M. Quer: None. J. Craven-Bartle: None. X. León: None.