Abstract
PurposeThe role of lymph node ratio (LNR, ratio of metastatic to examined nodes) in the staging of multiple human malignancies has been reported. We aim to evaluate its value in salivary gland cancer (SGC).MethodsRecords of SGC patients from Surveillance, Epidemiology, and End Results database (SEER, training set, N = 4262) and Fudan University Shanghai Cancer Center (FUSCC, validating set, N = 154) were analyzed for the prognostic value of LNR. Kaplan–Meier survival estimates, the Log-rank χ2 test and Cox proportional hazards model were used for univariate and multivariate analysis. Optimal LNR cutoff points were identified by X-tile.ResultsOptimal LNR cutoff points classified patients into four risk groups, R0, R1 (≤ 0.17), R2 (0.17–0.56) and R3 (> 0.56), corresponding to 5-year cause-specific survival in SEER patients of 88.6%, 57.2%, 53.1% and 39.7%, disease-free survival in FUSCC patients of 69.2%, 63.3%, 34.6% and 0%, and disease-specific survival in FUSCC patients of 92.3%, 90.0%, 71.4% and 0%, respectively. Compared with TNM staging, TNM + R staging showed smaller AIC values and higher C-index values in the Cox regression model in both patient sets.ConclusionsLNR classification should be considered as a complementary system to TNM staging and LNR classification based clinical trials deserve further research.
Highlights
Salivary gland cancer (SGC) accounts for 7–12% of head and neck cancers and has an increasing incidence [1–3]
Laterality and size of metastasized lymph nodes, they are classified as N1–N3 according to the American Joint Committee on Cancer (AJCC) staging system [7]
Univariate analysis identified that primary sites, histologic subtype, grade, T, N, and M classification were all prognostic factors of SEER causespecific survival (CSS)
Summary
Salivary gland cancer (SGC) accounts for 7–12% of head and neck cancers and has an increasing incidence [1–3]. Lymph node (LN) involvement is among the most important prognostic factors in SGCs [3–6]. Patients with pathological lymph node metastasis (pN+) are recommended for postoperative radiotherapy according to the National Comprehensive Cancer Network (NCCN) guideline [7]. Laterality and size of metastasized lymph nodes, they are classified as N1–N3 according to the American Joint Committee on Cancer (AJCC) staging system [7]. To improve the prognostic system, one would intuitively take information on positive LNs and the number of LNs examined (LNE) into account. Lymph node ratio (LNR), defined as the number of involved nodes divided by LNE, was found to improve prognostic information in breast, gastric, colorectal, bladder and skin cancers [8–12]. The subsequent study showed that the LNR improved the comparisons between institutions compared with AJCC
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
