Prognostic Involvement of Lymph Node Density in Oral Squamous Cell Carcinoma. A New Predictive Model.

PURPOSE: Lymph node density (LND) has been reported to be a significant predictor of survival in oral squamous cell carcinoma (OSCC). The aim of this study was to analyze LND as a prognostic factor in OSCC and create a predictive model that determines the probability of death in these patients. METHODS: A retrospective cohort study was carried out with a cohort of patients who underwent cervical dissection and primary resection of OSCC between 1980 and 2020. The primary predictor variable in this study was LND, which is defined as the number of positive lymph nodes divided by the total number of lymph nodes removed. The cutoff values for prediction of disease-specific survival (DSS) were calculated by receiver operating characteristic curve analysis, which determined the best cutoff value was 0.07. Patients were divided into binary subgroups (low and high risk) using the best cutoff value of LND. The outcome variable was DSS, defined as the duration from the date of diagnosis to death due to OSCC and not due to other causes or secondary tumors. Other variables were type of neck dissection, postsurgical treatment, surgical margin, pathological T category stage, pathological N category (pN) stage, extranodal extension, perineural invasion, bone invasion, and presence of recurrence. A predictive model (score) was generated by selecting variables using a log-rank test and by using the Cox proportional-hazards regression (multivariate analysis). RESULTS: The sample consisted of 368 patients, 252 (68.5%) male and 116 (31.5%) female patients, with a mean age of 60.3 years. According to the LND cutoff value, there were 289 patients with a low LND (≤0.07) and 79 with a high LND (>0.07). The univariate analysis showed LND as a significant predictor of DSS at 5 years (67.1% in LND ≤ 0.07 vs 32.9% in LND > 0.07; P < .001). The Cox multivariate analysis identified LND (hazard ratio [HR] = 27.2; 95% confidence interval [CI], 3.18-231; P = .002), recurrence (HR = 4.45; 95% CI, 2.3-8.4; P < .001), and type of treatment (HR = 0.52; 95% CI, 0.34-0.81; P < .001) as independent predictive factors for DSS. In the predictive model, the presence of recurrence was the most important factor with 8 points, whereas LND >0.07 contributed only 1 point; however, the 2 categories resulting from this limit were statistically significant. CONCLUSIONS: Our study demonstrates that LND is an additional prognostic factor in patients with a pN+ disease. In addition, our predictive model could be useful in the therapeutic algorithm of OSCC patients, as it can predict the probability of death in these patients.

Improved Quality of Life After Mandibular Advancement by Bilateral Internal Ramus Distraction.

BACKGROUND: Obstructive Sleep Apnea (OSA) is a significant health issue due to noncompliance with continuous positive airway pressure treatment. Therefore, evaluating alternative treatments is crucial. PURPOSE: Analyze the impact of maxillomandibular advancement using bilateral internal ramus distraction (BIRD) on quality of life (QOL) in OSA patients. STUDY DESIGN, SETTING, AND SAMPLE: A prospective cohort study was conducted at the Oral and Maxillofacial Surgery Department of the University Hospital "La Princesa." The study included patients with moderate to severe OSA who were treated with the BIRD approach. PREDICTOR VARIABLE: Changes in measured variables were analyzed at three time points: before surgery (T1), after mandibular advancement (T2), and after maxillary advancement (T3). MAIN OUTCOME VARIABLE(S): QOL changes measured by Quebec Sleep Questionnaire and the Epworth Sleepiness Scale. Secondary outcomes included: apnea-hypopnea index (AHI), oxygen desaturation index, and percentage of time with saturation below 90%. COVARIATES: Age, sex, continuous positive airway pressure treatment, cephalometric variables and cardiovascular risk parameters were considered. ANALYSES: Statistical analysis employed the Friedman test and χ2 test, with a significance level of P ≤ .05. RESULTS: The study included 32 patients (22% with moderate OSA, 78% with severe OSA). Epworth Sleepiness Scale scores significantly decreased between T1 (13.4 ± 4.4) and T2 (5.8 ± 3.6) and T3 (1.9 ± 1.8) (P < .001). QOL improvements were observed in all domains: daytime sleepiness T1 (3.0 ± 1.3) T2 (5.4 ± 1.4) T3 (6.3 ± 1.0); diurnal symptoms T1 (2.5 ± 1.4) T2 (5.2 ± 1.3) T3 (6.2 ± 1.1); nocturnal symptoms T1 (2.5 ± 1.1) T2 (5.6 ± 1.1) T3 (6.5 ± 0.8); emotions T1 (2.6 ± 1.6) T2 (5.3 ± 1.4) T3 (6.5 ± 0.9); and social interaction T1 (2.5 ± 1.6) T2 (5.4 ± 1.6) T3 (6.3 ± 1.2) (P < .001). AHI decreased between T1 (47.9 ± 23.1) and T2 (14.4 ± 14.3) and T3 (4.7 ± 5.6) h-1 (P < .001), with a final cure rate of 81.2% (defined as final AHI<5 h-1). Oxygen desaturation index and percentage of time with saturation below 90% also showed significant reductions (P < .001). CONCLUSIONS AND RELEVANCE: BIRD approach for OSA demonstrated a high cure rate and significant QOL improvements. It shows promise as an effective surgical option. Further research and long-term follow-up are needed.