Importance of lymph node ratio for locoregional recurrence of squamous cell carcinoma of the buccal mucosa

Comparison of alternative N-staging models in patients with oral cancer. Is nodal yield or burden the most critical parameter?

BACKGROUND

There is increasing evidence in the literature that alternative N-classification systems offer a simpler and more precise risk stratification than the current N- classification in patients with oral squamous cell carcinoma. The purpose of this study is to compare three broadly proposed models incorporating lymph node ratio, log odds of positive lymph nodes and number of positive lymph nodes regarding disease-free and overall survival.

METHODS

This is a retrospective study of patients treated in a single center between 2013 and 2019. Cox proportional hazard models, Kaplan Meier curves, the long rank test and the area under the curve were implemented to compare the risk-stratification ability of the three models. Moreover, a hazard ratio plot was calculated to investigate the association between nodal yield and disease-free survival.

RESULTS

231 patients were included. All three proposed N-models were significantly correlated to the patient's prognosis in the multivariate analysis. Pairwise comparisons between the groups showed that the current pN classification offers the worst stratification and that the model incorporating the number of positive lymph nodes had a better performance for predicting both endpoints. Finally, a decrease in hazard ratio was observed with each additional lymph node removed up to the number of 39 lymph nodes.

CONCLUSIONS

The model incorporating the nodal burden offered a better predictive ability. The current N-classification cannot adequately identify patients with different prognosis. A non-linear relationship was found between nodal yield and survival, which could be the disadvantage of the lymph node ratio and log odds models.

Clinical, Radiological and Histological Features and Their Association with Extranodal Extension in Buccoalveolar Complex Squamous Cell Carcinoma

Jeyashanth RijuObjectives  The study was aimed to (1) evaluate the effectiveness of clinical examination, intraoperative finding, and contrast-enhanced computed tomography (CECT) to detect extranodal extension (ENE) in buccoalveolar complex squamous cell carcinoma (BAOSCC), (2) to know various factors influencing ENE, and (3) to evaluate survival outcome in patients with ENE. Materials and Methods  This was a retrospective cohort study, which included 137 patients with BAOSCC who underwent curative treatment between May 2019 and April 2021. Collaborative findings suggestive of ENE were noted during preoperative clinical examination, CECT, and intraoperatively, and their efficacy was compared with postoperative histopathology. Also, the various factors associated with ENE were evaluated and compared. Statistical Analysis  Univariate and multivariate analysis of parameters was done using multiple logistic regression analysis and significant correlation was determined using chi-square test between ENE positive and negative categories. Analysis of prognosis and survival was done by Kaplan-Meier curve plotting using regression analysis and its significance was compared. Results  The overall prevalence of ENE was 18.98% and that of lymph node involvement was 40.88%. CECT (73.1%) was found to be more sensitive in detecting ENE compared to intraoperative examination (46.2%) and clinical examination (34.6%).In comparison with clinical examination (91.9%) or CECT (78.38%), intraoperative examination (93.7%) showed the highest specificity in detecting ENE. Clinical nodal size ≥ 3 cm ( p ≤ 0.001), fixity ( p ≤ 0.001), and clinical number of nodes ( p ≤ 0.001) had significant association with ENE. The presence of thick nodal walls on CECT increased the probability of predicting ENE 15 times ( p  = 0.180, confidence interval: 0.3-765.4). After a mean follow-up of 18 months, subjects without nodal positivity had a survival advantage over patients with positive lymph nodes (86.4% vs. 53.3%) and those with ENE (86.4% vs. 23.2%), respectively. Conclusion  The results demonstrated that clinical examination can be used as an adjuvant to radiological imaging for prediction of ENE preoperatively. Clinical finding suggesting size of node ≥ 3 cm and ≥ 2 nodes are strong predictor of ENE, in addition to other known predictors. Patients with ENE had an unfavorable prognosis when compared with subjects with metastatic nodes without ENE. Presence of ENE remains one of the strongest factors predicting recurrence and thus poor prognosis.

Worst Pattern of Invasion as an Independent Predictor of Lymph node Metastasis and Prognosis in oral Cavity Squamous cell carcinoma - A Retrospective Cohort Study

Although Worst pattern of invasion (WPOI) is one of the histopathological (HP) markers that has been utilized in risk stratification of oral squamous cell carcinoma (OSCC) patients, its potential as an independent predictive factor for lymph node metastasis (LNM) and prognosis is least analyzed. Aim of the study is to analyze the relationship of various HP parameters to WPOI, their propensity for lymph node metastasis and prognostic value. This retrospective study included 140 patients diagnosed with resectable OSCC who underwent definitive surgery. Multiparametric HP risk assessment was done on the postoperative specimen and patients were categorized as low-risk WPOI (Type 1-3), and high-risk group (type 4 and 5). After categorization, 36.1% patients had low-risk WPOI and 63.9% had high-risk WPOI. Significant association was noted between WPOI and patient's age (p = 0.001), nodal stage (p = 0.001), lymphovascular invasion (LVI) (p = 0.006) and neural invasion (p = 0.001). 87% patients with nodal metastasis had high risk WPOI. LVI (p = 0.014) and WPOI (p < 0.001) had significant predictive role in LNM. High-risk WPOI and bone involvement were found to be predictive factors for overall survival, and only high risk WPOI had strong correlation with disease free survival having significant poor prognosis. Analyzing WPOI is essential in reporting HP specimens in OSCC. High-risk WPOI can act as an independent predictor for LNM, early recurrence and poor prognosis. Incorporation of WPOI into TNM staging is recommended to improve clinician's ability to prognosticate and individualize treatment strategies.

Improved Cancer-Specific Risk Stratification by the Lymph Node Ratio-Based Nomogram: A Potential Role in Guiding Postoperative Management Decisions for Oral Cavity Carcinoma

PURPOSE

To develop and validate a nomogram integrating lymph node ratio (LNR) to predict cancer-specific survival (CSS) and assist decision making for postoperative management in nonmetastatic oral cavity squamous cell carcinoma (OCSCC).

MATERIALS AND METHODS

We retrospectively retrieved 6,760 patients with OCSCC primarily treated with surgery from surveillance, epidemiology, and end results database between 2010 and 2015. They were randomly divided into training and validation cohorts. Performance of the nomogram was evaluated by calibration curve, consistency index, area under the curve, and decision curve analysis and was compared with that of the LNR, positive lymph nodes (PLN) and tumor node metastasis (TNM) staging. According to the individualized nomogram score, patients were classified into three risk cohorts. The therapeutic efficacy of postoperative radiotherapy and chemotherapy was evaluated in each cohort.

RESULTS

The nomogram incorporated six independent variables, including race, tumor site, grade, T stage, PLN, and LNR. Calibration plots demonstrated a good match between the predicted and observed CSS. C-indices for training and validation cohorts were 0.746 (95% CI, 0.740 to 0.752) and 0.726 (95% CI, 0.713 to 0.739), compared with 0.687, 0.695, and 0.669 for LNR, PLN, and TNM staging, respectively (P < .001). Decision curve analyses confirmed that nomogram showed the best performance in clinical utility. Postoperative radiotherapy presented survival benefit in medium-and high-risk groups but showed a negative effect in the low-risk group. Chemotherapy was only beneficial in the high-risk group.

CONCLUSION

The LN status-incorporated nomogram demonstrated good discrimination and predictive accuracy of CSS for patients with OCSCC and could identify those most likely to benefit from adjuvant therapy.

Contralateral Nodal Metastasis from Tongue Malignancy

Oral cavity is the most common site of cancer in India, tongue forms the most common single subsite. Neck node involvement plays an important prognostic role in disease-free survival and overall survival. Most of the nodal metastasis are occult and only an elective neck dissection can disclose the nodal metastasis, which is accepted only when the risk of metastasis exceeds 15-20%. Contralateral nodal metastasis(CLNM) are rarely analyzed due to sparse event.Retrospective analysis of data of patients who underwent surgery for carcinoma tougue with a curative intend between April 2017 and March 2019 were collected. Factors influencing CLNM in carcinoma tongue were studied.The study included 149 patients, with 102 men and 47 women. The mean age of study subjects was 51.5 ± 11.8 years. Thirteen (8.7%) patients had CLNM. With respect to tumor, advanced stage(p < 0.001), floor of mouth involvement(p = 0.001) and lesion crossing midline(p < 0.001) had an increased risk of CLNM. Extranodal extension(ENE)(p < 0.001) and lymphnode ratio(p = 0.002) in ipsilateral node ratio influenced CLNM. Multivariant analysis showed that in addition to lesion crossing midline(p = 0.03), ENE played significant role in CLNM (p < 0.001), with a risk of 12.8 times compared to no ENE. Suspicion of CLNM either clinically/radiologically was a good predictor of metastasis(p < 0.001).CLNM in tongue cancer was significantly influenced by lesion crossing midline and ENE. Contralateral neck dissection should be performed in any case with clinical/radiological suspicion of nodal involvement and above mentioned risk factors.

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 &lt;0.0001) and 61%/52%/40%25%, respectively (p &lt;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 &lt;0.0001) and 63%/51%/67%/33%, respectively (p &lt;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.

Nomograms predicting the overall and cancer-specific survival of patients with buccal mucosa cancer

OBJECTIVES

To construct predictive models for predicting overall survival (OS) and cancer-specific survival (CSS) of patients with buccal mucosa cancer (BMC).

STUDY DESIGN

Data of 936 patients with BMC were extracted from the Surveillance, Epidemiology, and End Results (SEER) database from 2004 to 2015. Nomograms were constructed based on multivariate Cox regression analyses, and validated using calibration plots, time-dependent receiver operating characteristic curves, and decision curve analyses.

RESULTS

Age at diagnosis, marital status, grade, histopathology, SEER stage, tumor size, and surgery were associated with OS, whereas age at diagnosis, grade, histopathology, SEER stage, tumor size, and surgery were associated with CSS (all P < .05). The concordance indexes for OS and CSS were 0.79 and 0.80 in the training cohort, respectively, and those in the validation cohort were 0.78 and 0.80. Time-dependent receiver operating characteristic curves showed great predictability in nomograms. Decision curve analyses demonstrated good clinical value for OS (4%-88%) and CSS (3%-77%) nomograms. Patients were stratified into 3 risk groups, with the worst prognosis in the high-risk subgroup (P < .001).

CONCLUSIONS

We developed and validated 2 nomograms predicting OS and CSS and established the corresponding risk classification systems in patients with BMC. These models assisted in precise administration of individual therapeutic regimens.

Evaluation of lymph node ratio and lymph node yield as prognosticators of locoregional recurrence in p16-associated oropharyngeal squamous cell carcinoma

BACKGROUND

The prognostic value of lymph node yield (LNY) and lymph node ratio (LNR), or the ratio of number of metastatic LNs to total number dissected, has not been well established in p16-associated oropharyngeal squamous cell carcinoma (OPSCC).

METHODS

This retrospective cohort study evaluated locoregional disease-free survival (LRDFS) in 82 patients with p16+ OPSCC who underwent neck dissection at a single institution from 2009 to 2017. LNR and LNY cutoffs were estimated using time-dependent receiver operator characteristic (ROC) curves. Prognostic significance of these cutoffs was compared with Eighth Edition AJCC Nodal Staging.

RESULTS

An increased LNR ≥ 0.129 was associated with worse 2-year LRDFS (66.9% vs 96.8%, P = .005). LNY was not significantly associated with LRDFS (P = .304). An LNR-based risk model was a better prognosticator than Eighth Edition AJCC Nodal Staging (Harrell's C, 0.9065 vs 0.7668).

CONCLUSIONS

LNR has good prognostic utility in predicting LRDFS in p16+ OPSCC, but further evaluation of this measure is warranted.

Elective neck dissection versus wait-and-see policy in cT1N0 buccal squamous cell carcinoma

Background

Our goal was to clarify the comparison between elective neck dissection (END) and the wait-and-see policy in neck management for cT1N0 buccal squamous cell carcinoma (SCC).

Methods

This was a retrospective comparison of 175 prospectively enrolled patients with cT1N0 buccal SCC. The patients were divided into two groups based on the nonrandomized management of the neck: 125 patients received END, and 50 patients were exposed to the wait-and-see policy. The main study endpoints were locoregional control (LRC) and disease-specific survival (DSS). Patients were asked to complete the shoulder domain in the University of Washington quality of life questionnaire, version 4, 1 year postoperatively.

Results

Ten of the patients undergoing END developed recurrence, and the 5-year LRC rate was 92%. Five patients undergoing the wait-and-see policy developed recurrence, and the 5-year LRC rate was 90%. The difference was not significant (p = 0.668). There were 6 deaths in patients undergoing END, and the 5-year DSS rate was 94%. There were 3 deaths in patients undergoing the wait-and-see policy, and the 5-year DSS rate was 94%; the difference was not significant (p = 0.777). The mean shoulder scores of patients undergoing END and the wait-and-see policy were 93.9 and 100, respectively, and the difference was not significant (p = 0.284).

Conclusion

Elective neck dissection does not carry a survival benefit compared to the wait-and-see policy, and it is not suggested for patients with cT1N0 buccal SCC.

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.

Oral Cancer: Integration of Studies for Diagnostic and Therapeutic Precision

Head and neck cancers are among the 10 most common cancers in the world and include cancers of the oral cavity, hypopharynx, larynx, nasopharynx, and oropharynx. At least 90% of head and neck cancers are squamous cell carcinomas (SCCs). This summary discusses the integration of clinical and mechanistic studies in achieving diagnostic and therapeutic precision in the context of oral cancer. Specifically, based on recent mechanistic studies, a subsequent study reevaluated current diagnostic criteria of perineural invasion in patients with oral cavity SCC showing that overall survival could be associated with nerve-tumor distance; validation of the findings of this study from a small group of patients could lead to a personalized approach to treatment selection in patients with oral cavity SCC. Moreover, delineation of key pathways in SCC revealed novel treatment targets that can be exploited to develop personalized treatment strategies to achieve long-term remission.