Lymph node ratio as prognosticator in floor of mouth squamous cell carcinoma patients

Potential of lymph-node ratio as a prognostic factor for patients with oral squamous cell carcinoma

BACKGROUND

To analyze the influence of the lymph node ratio (LNR) in survival of patients with OSCC METHODS: Clinicopathologic data from patients with OSCC who were treated with curative surgery and neck dissection (ND) with or without adjuvant therapies from 1991 to 2015 was retrospectively assessed. The impact of LNR and other variables on overall survival (OS) and disease-free survival (DFS) was analyzed in univariate and multivariate analyses.

RESULTS

One hundred nineteen patients were included. In the univariate analysis the LNR had a significant impact on OS (p = 0.01) and DFS (p = 0.01). In the multivariate analysis, the LNR was the only significantly independent factor influencing in the OS (p = 0.03). The adjuvant therapies did not influence on the OS (p = 0.42) and DFS (p = 0.10).

CONCLUSIONS

The LNR is an independent prognostic factor in patients with OSCC. The LNR alone is not recommended to indicate the performance of adjuvant therapies.

Influence of different methods for classification of lymph node metastases on the survival of patients with oral squamous cell carcinoma

BACKGROUND

Despite the advances in the classification of oral squamous cell carcinoma (OSCC) based on its extension by the TNM system, there is still a need for methods to better classify the patients to predict prognosis and indicate adjuvant therapy.

OBJECTIVES

To analyze the influence of the number of positive lymph nodes (PN), lymph node ratio (LNR), and log odds of positive lymph nodes (LODDS) in survival of patients with OSCC.

METHODS

Clinicopathologic data from patients with OSCC who were treated with curative purposes by surgery and neck dissection (ND) with or without subsequent adjuvant therapies from 1991 to 2015 was retrospectively assessed. The impact of the PN, LNR, LODDS, and other variables on overall survival (OS) and disease-free survival (DFS) was analyzed in univariate and multivariate analyses.

RESULTS

One hundred nineteen patients were included in this study. In the univariate analysis the PN had a significant impact on OS (p = 0.001) and DFS (p = 0.020), and the LNR had a significant impact on the OS (p = 0.042). In the multivariate analysis with other relevant clinicopathologic variables, the PN was the only significantly independent factor influencing in the OS (p = 0.017) but not in DFS (p = 0.096).

CONCLUSIONS

The PN is an independent prognostic indicator for OS and DFS in patients with OSCC and has the potential to aggregate the current AJCC classification. The LNR has potential to be an important prognostic indicator, but the methods for this classification require lapidation. The LODDS did not demonstrate prognostic potential.

Lymph Node Ratio as a Prognostic Factor in Neck Dissection in Oral Cancer Patients: A Systematic Review and Meta-Analysis

Simple Summary

Lymph node ratio (LNR) is a well-studied prognostic factor in colorectal and breast cancer, and it has been recently evaluated as a clinically relevant biomarker in oral squamous cell carcinoma. LNR represents the ratio of positive lymph nodes extracted in a neck dissection to the total number of nodes harvested (lymph node yield, LNY). Many single-center cohort studies and a few multicenter have assessed the significance of LNR as a prognostic factor in oral cancer. In this systematic review and meta-analysis of 32 studies and 20,994 oral cancer patients, we demonstrate that LNR is an independent prognostic indicator in patients with oral squamous cell carcinoma.

Abstract

Many studies have evaluated the clinical implications of lymph node ratio (LNR) as a prognostic factor in patients with oral squamous cell carcinoma (OSCC). The main purpose of this systematic review and meta-analysis was to address LNR as a prognosticator in patients with OSCC. A systematic search was conducted in the following databases: PubMed, EMBASE, Google Scholar, OpenGrey, Cochrane library, and ClinicalTrials.gov, and studies between 2009 and 2020 were sought. The pooled relative risk was calculated along with 95% confidence intervals for the following endpoints: overall survival (OS), disease-free survival (DFS), disease-specific survival (DSS), distant metastasis-free survival (DMFS), locoregional disease-free survival (LRDFS), local recurrence-free survival (LRFS), and recurrence-free survival (RFS) according to the random-effects model (Der Simonian–Laird approach). Subgroup and meta-regression analyses were performed as well. Finally, 32 cohort studies were eligible, which included 20,994 patients with OSCC. Patients were subdivided into two categories, group YES (studies that included in their analysis only patients with positive lymph nodes) and group NO (studies that did not exclude LNR = 0 patients). In the group YES, patients with high LNR had shorter OS (RR = 1.68, 95% CI: 1.47–1.91), DFS (RR = 1.68, 95% CI: 1.42–1.99), DSS (RR = 1.94, 95% CI: 1.56–2.42), DMFS (RR = 1.83, 95% CI: 1.13–2.96), LRDFS (RR = 1.55, 95% CI: 1.10–2.20), and LRFS (RR = 1.73, 95% CI: 1.41–2.13) compared to patients with low LNR. In the group NO, patients with high LNR in comparison had shorter OS (RR = 2.38, 95% CI: 1.99–2.85), DFS (RR = 2.04, 95% CI: 1.48–2.81), and DSS (RR = 2.90, 95% CI: 2.35–3.57) compared to patients with low LNR. Based on those findings, LNR might be an independent prognostic factor for OS in patients with OSCC and could be incorporated into future classification systems for better risk stratification.

Towards an Improved Pathological Node Classification for Prognostic Stratification of Patients With Oral Cavity Squamous Cell Carcinoma: Results From a Nationwide Registry Study

Background

To assess the prognostic significance of different nodal parameters [i.e., number of pathologically positive nodes, log odds of positive lymph nodes, lymph node ratio (LNR), and extra-nodal extension (ENE)] in Taiwanese patients with oral cavity squamous cell carcinoma (OCSCC), and to devise an optimized pN classification system for predicting survival in OCSCC.

Methods

A total of 4287 Taiwanese patients with first primary OCSCC and nodal metastases were enrolled. Cox proportional hazards regression analysis with the spline method was applied to identify the optimal cut-off values for LNR, log odds of positive lymph nodes, and number of pathologically positive nodes.

Results

On multivariable analysis, we identified a LNR ≥0.078/0.079, the presence of at least three pathologically positive nodes, and ENE as independent prognosticators for 5-year disease-specific survival (DSS) and overall survival (OS) rates. We therefore devised a four-point prognostic scoring system according to the presence or absence of each variable. The 5-year DSS and OS rates of patients with scores of 0−3 were 70%/62%/50%/36% (p <0.0001) and 61%/52%/40%25%, respectively (p <0.0001). On analyzing the AJCC 2017 pN classification, patients with pN3a displayed better survival rates than those with pN2 disease. The 5-year DSS and OS rates of patients with pN1/pN2/pN3a/pN3b disease were 72%/60%/67%/43% (p <0.0001) and 63%/51%/67%/33%, respectively (p <0.0001).

Conclusions

Three nodal parameters (i.e., a LNR ≥0.078/0.079, the presence of at least three pathologically positive nodes, and ENE) assessed in combination provided a better prognostic stratification than the traditional AJCC pN classification.

Lymph node ratio-dependent prognosis stratification and postoperative radiotherapy utilization in T1-2N1 oral cavity carcinoma

OBJECTIVE

Pathological T1-2N1 oral cavity squamous cell carcinoma (pT1-2N1 OCSCC) is a setting with intermediate prognosis whilst without consensus regarding the utilization of postoperative radiotherapy (PORT). This study aimed to investigate the prognostic value of lymph node ratio (LNR) and to further examine its clinical validity for guiding PORT in pT1-2N1 OCSCC.

METHODS

OCSCC patients who received surgery between 2010 and 2015 with at least 6 lymph nodes dissection were extracted from the Surveillance, Epidemiology and End Results (SEER) database. Time-dependent receiver operating characteristic (ROC) analysis was used to identify the optimal cutoff of LNR. Multivariable Cox regression analysis was employed to assess the prognostic value of LNR. Impact of PORT was evaluated in respective subgroups stratified by LNR.

RESULTS

A total of 870 OCSCC patients with pT1-2N1 diseases were eligible for analysis. The 5-year overall survival (OS) and disease-specific survival (DSS) was 57.2% and 67.9% respectively. Time-dependent ROC analyses for OS and DSS concordantly revealed 5.5% as the optimal cutoff of LNR. Significantly higher risks of death (HR = 1.610, 95% CI: 1.139-2.276) and disease-specific death (HR = 1.731, 95% CI: 1.101-2.723) were unveiled in patients with LNR > 5.5%. PORT related improvement on OS (5-year rate: 57.6% vs. 47.3%, p = 0.095) and DSS (5-year rate: 71.0% vs. 53.8%, p = 0.030) was only found in LNR > 5.5% subgroup.

CONCLUSIONS

LNR > 5.5% is indicative of inferior outcome in pT1-2N1 OCSCC, warranting the utilization of PORT in this sub-setting.

Prognostic significance of lymph node ratio in patients with squamous cell carcinoma of the floor of the mouth

The lymph node ratio (LNR) has been proposed as an independent prognostic factor for survival in patients with oral squamous cell carcinoma (OSCC). However, little attention has been paid to its role in the specific subsite of the floor of the mouth (FOM). The purpose of this study was to evaluate the prognostic significance of the LNR in patients with FOM SCC. A retrospective analysis of 92 patients with FOM SCC who were treated with primary curative resection and neck dissection was conducted. Overall survival (OS) and disease-free survival (DFS) were used to evaluate the prognostic significance of the LNR. Both of these parameters were significantly worse (P < 0.001) in patients with neck metastases. The mean LNR was 0.145 in patients with positive lymph nodes. A LNR <0.145 was predictive of longer DFS, while the receiver operating characteristic curve analysis demonstrated that a LNR ≥0.175 indicated a significantly lower OS. This study confirms that metastatic cervical lymph nodes correlate with an adverse prognosis in patients with FOM SCC, and specifically, a LNR ≥0.145 is predictive. Therefore, the LNR in patients with FOM SCC may be a predictor of survival in these patients.

[Expression of cyclophilin A in oral squamous cell carcinoma and its effect on cell proliferation and invasion]

OBJECTIVES

To investigate the expression of cyclophilin A (CyPA) in oral squamous cell carcinoma (OSCC) and explore the effect of downregulating the expression of CyPA gene on the proliferation and invasion of SCC-25 cells.

METHODS

A total of 77 cases of patients with OSCC were selected. The expression levels of CyPA proteins in OSCC and adjacent normal tissues were evaluated. SCC-25 cells were cultured and divided into the CyPA interference sequence group, negative control group, and blank group. The expression levels of CyPA mRNA and protein in cells were detected by using real-time fluorescent quantitative polymerase chain reaction and Western blot, respectively. Cell proliferation was detected by using methyl thiazolyl tetrazolium and plate colony formation assays. Cell invasion was detected by using Transwell assay.

RESULTS

The positive expression rate of CyPA protein in OSCC tissues was 76.62%, which was higher than that in adjacent tissues (P<0.05). The positive expression rate of CyPA protein in TNM stage T₃+T₄, clinical stage Ⅲ+Ⅳ, moderately or poorly differentiated lymph node metastasis was increased (P<0.05). Compared with the negative control and blank groups, the CyPA interference sequence group had decreased relative expression levels of CyPA mRNA and protein (P<0.05); optical density va-lues of cells at 24, 48, 72, and 96 h (P<0.05); and number of cell colonies and invasive cells (P<0.05).

CONCLUSIONS

The CyPA protein is highly expressed in OSCC tissues, and the downregulation of CyPA gene expression in SCC-25 cells can reduce cell proliferation and inhibit cell invasion.

Lymph node ratio as a predictor for outcome in oral squamous cell carcinoma: a multicenter population-based cohort study

Objectives

Recently, multiple studies addressed the importance of lymph node ratio (LNR) in specifying patients’ risk of disease recurrence in various malignancies. The present study examines the prognostic significance of LNR in predicting outcome of oral squamous cell carcinoma (OSCC) patients after surgical treatment with curative intent.

Methods

Here, we describe a retrospective population-based cohort with 717 patients previously diagnosed with OSCC. Histopathologically verified lymph node metastasis was diagnosed in 290 patients. Among these patients, we evaluated the impact of LNR on overall survival (OAS) and recurrence-free survival (RFS) in uni- as well as multivariate analysis.

Results

A median cutoff (0.055) in LNR was found to significantly predict outcome in OSCC patients. Five-year OAS was 54.1% in patients with a low LNR, whereas a high LNR was associated with a 5-year OAS of 33.3% (p < 0.001). Similar results were detected for RFS with a 5-year survival rate of 49.8% (LNR low) and 30.3% (LNR high) (p = 0.002). Results were confirmed in multivariate Cox regression which substantiated the importance of LNR in predicting survival in OSCC patients.

Conclusions

LNR was shown to be an independent prognostic factor for outcome of OSCC in a population-based cohort in uni- as well as multivariate analysis. Hereby, a LNR ≥ 0.055 predicted a shorter OAS and RFS in our cohort.

Clinical relevance

Besides established histopathological factors, LNR can be used as a reliable predictor of outcome in OSCC and might therefore be further applied in evaluating adjuvant treatment after resection in curative intention.

The prognostic significance of the lymph node ratio in oral cancer differs for anatomical subsites

The aim of this study was to validate the prognostic significance of the lymph node ratio (LNR) in patients suffering from oral squamous cell carcinoma in regard to different anatomical subsites. A cohort of 430 patients was investigated to determine the rates of primary metastasis and local and regional disease recurrence. Correlation analysis of the LNR with relevant clinical and pathological parameters was performed. Receiver operating characteristic (ROC) curve analysis was conducted to evaluate the prognostic impact for different subsites. Significantly differing rates of primary metastasis and loco-regional disease recurrence were found for cancer of different anatomical subsites of the head and neck. Furthermore, ROC curve analysis suggested that LNR has prognostic relevance in subsets of cancer (tongue, P< 0.001; alveolar process, P= 0.04; maxilla, P= 0.03; buccal mucosa, P= 0.02). The LNR of cancer located in the soft palate (P= 0.6) and floor of the mouth (P= 0.11) showed little or no association with the clinical outcome. There is the need for a more sensitive consideration of the LNR as a factor in the assessment of risk and the treatment decision, as the anatomical subsite plays a crucial role in its impact on the clinical outcome.