Locoregional recurrence rate and disease-specific survival following marginal vs segmental resection for oral squamous cell carcinoma with mandibular bone invasion

The Prognostic Role of Perineural Invasion for Survival in Head and Neck Squamous Cell Carcinoma: A Systematic Review and Meta-Analysis

The aim of this study was to conduct a comprehensive review of the predictive significance of PNI in HNSCC survival outcomes. A systematic search was conducted across multiple databases, and all studies published in the last decade were screened (Research Registry ID: reviewregistry1853). The included studies were assessed using the Quality in Prognosis Studies tool. Survival outcome data were extracted, combined, and presented as hazard ratios (HR) with a 95% confidence interval (CI). Totally, 74 studies encompassing 27,559 patients were analyzed and revealed a cumulative occurrent rate of 30% for PNI in HNSCC. PNI+ HNSCC patients had a worse overall survival (HR: 1.91, 95% CI: 1.71-2.13), disease-specific survival (HR: 1.79, 95% CI: 1.55-2.07), disease-free survival (HR: 1.82, 95% CI: 1.69-1.96), local recurrence (HR: 2.54, 95% CI: 1.93-3.33), locoregional recurrence (HR: 2.27, 95% CI: 1.82-2.82), locoregional relapse free survival (HR: 1.77, 95% CI: 1.28-2.45), distant metastasis (HR: 1.82, 95% CI: 1.34-2.48), and distant metastasis-free survival (HR: 2.97, 95% CI: 1.82-4.85) compared to those PNI- patients. The available evidence unequivocally establishes PNI as a critical prognostic factor for worse survival in HNSCC patients.

Cortical microarchitecture and remodeling-associated gene expression related to oral cancer prognosis

The objective of this study was to assess the remodeling-associated gene expression in the mandible of patients diagnosed with oral squamous cell carcinoma (OSCC), investigating the cortical microarchitecture, and their influence on disease-free survival (DFS) and overall survival (OS) rates. A total of twenty-four patients who underwent mandibulectomy for OSCC treatment had two bone fragments harvested from the mandible for gene expression (RANK, RANKL, OPG, and SOST), and microarchitecture analysis, including bone volume, surface, mineral density, degree of anisotropy, and fractal dimension. The prognosis of the patients was assessed. The results revealed that RANK, RANKL, and SOST were predominantly downregulated, while OPG was completely downregulated. Tumors located adjacent to the posterior region of the mandible (p = 0.02), with a bone mineral density below 1.03 g/cm3 HA (p = 0.001), and a bone volume less than 86.47% (p = 0.03) were associated with poor outcomes. In conclusion, bone-remodeling-associated genes exhibited downregulation in the cortex of the mandible in OSCC patients. Additionally, the tumor's location within the mandible, bone volume, and cortical bone mineral density were identified as factors impacting DFS.

Evaluation of outcomes after conservative mandibular surgery in patients with oral squamous cell carcinoma

This study aimed to assess preoperative radiological and clinical examinations for identifying bone status and to evaluate survival outcomes in patients undergoing marginal mandibulectomy for the primary treatment of oral squamous cell carcinoma. The medical records, enhanced computed tomography (CT) scans, and pathological specimens of these patients were reviewed. Disease-free (DFS), local recurrence-free (LRFS), and osteoradionecrosis-free (ORNFS) survival were analysed. The study included 104 patients. The preoperative CT and clinical examinations achieved a sensitivity of 45.8% and specificity of 100% for judging bone condition. LRFS was 79.6% and DFS was 68.8%. Pathological bone invasion in significantly affected DFS (P = 0.597), while DFS was significantly higher for those with a lower clinical tumour stage (1/2 vs 3/4; P = 0.005) and postoperative radiotherapy (P = 0.011). Among 39 patients receiving postoperative radiotherapy, ORNFS was 75.2%. Postoperative chemotherapy significantly decreased ORNFS (P = 0.009). Tumour subsite (P = 0.003) and the resection site (P = 0.035) significantly affected the remaining bone height. The results indicate that CT and clinical examinations cannot precisely identify superficial bone damage, but work well in selecting patients for marginal resection. Adhering to current indications, this resection approach can guarantee safe bone margins in terms of survival outcomes.

Marginal versus Segmental Mandibulectomy in the Treatment of Oral Cavity Cancer: A Systematic Review and Meta-analysis

Introduction  Oral cavity squamous cell carcinoma (OCSCC) is the most common malignancy in the oral cavity. Two types of mandibular resections have been described: the segmental mandibulectomy and the marginal mandibulectomy. Both may have a different impact over the quality of life, oncological prognosis, and functional or aesthetic result. Objectives  The aim of this study was to systematically explore the literature to determine the survival outcomes and disease control rates in patients who underwent segmental or marginal mandibulectomy for OCSCC with histological evidence of cortical and medullary bone invasion. Data Synthesis  This review involved a systematic search of the electronic databases MEDLINE/PUBMED, Google Scholar, Ovid Medline, Embase, and Scopus including articles from 1985 to 2019. Fifteen articles were included for qualitative analysis and 11 articles were considered for meta-analysis calculations. All of them correspond to retrospective cohort studies. Conclusion  This systematic review reveals the low-level evidence regarding the impact over local control or survival according to the type of mandibulectomy. Our results need to be considered with precaution according to the limited evidence available. We just found difference regarding the 5-year disease-free survival, and a tendency in favor of segmental mandibulectomy was confirmed when medullary invasion was evident.

Effect of segmental versus marginal mandibular resection on local and lymph node recurrences in oral squamous cell carcinoma: is tumorous bone infiltration or location and resulting soft tissue recurrences a long-term problem?

PURPOSE

Oral squamous cell carcinomas (OSCCs) adjacent to the mandible or with clinically suspected bone infiltration are surgically treated either with marginal or segmental resections. This retrospective study compared both resections regarding local recurrence and lymph node recurrence or secondary lymph node metastases.

METHODS

All consecutive primary OSCC cases between January 2007 and December 2015 that underwent mandibular marginal or segmental resection were included. Rates of local and lymph node recurrences or secondary metastases and possible risk factors such as tumor localization according to Urken's classification were recorded.

RESULTS

In total, 180 patients with 85 marginal (group I) and 95 segmental (group II) mandibular resections were analyzed. The local recurrence rates were comparable between the groups (28.2% vs. 27.4%; p = 0.897). Lymph node recurrences or secondary metastases were higher in group I (9.4% (n = 8) vs. 6.2% (n = 6); p = 0.001). Tumor localization appears to affect the outcomes. Significantly fewer local and lymph node recurrences/metastases were found for Urken's classification SB and S calculated by two-proportion z-test (p = 0.014 and 0.056, respectively). Local recurrences mostly emerged from soft tissues, which should be resected more radically than the bones.

CONCLUSION

While bone infiltration appears technically well controllable from an oncologic point of view, local recurrences and lymph node recurrences/metastases remain an issue. Regular clinical aftercare with imaging is crucial to detect recurrences.

Real-time detection of bone-invasive oral cancer with laser-induced breakdown spectroscopy: A proof-of-principle study

OBJECTIVES

Intraoperative definition of resection margin status in bone-invasive oral cancer is a fundamental problem in oncologic surgery due to the lack of rapid bone analysis methods. Laser-induced breakdown spectroscopy (LIBS) provides direct measurement with real-time examination of a minimal tissue sample. This proof-of-principle study aimed to evaluate the possibility of distinguishing tumorous and healthy areas with LIBS.

MATERIALS AND METHODS

LIBS experiments were executed on native segmental mandibulectomy specimens from 15 patients with bone-invasive oral cancer. Normalized and intensity-matched spectra were compared. Under biological derivation, peak area calculation and principal component analysis (PCA) were applied. The discriminatory power of the PCAs was correlated with the architectural and cytological characteristics of the lasered tumor tissue. Receiver operating characteristics analysis was used to evaluate the performance of LIBS in the real-time detection of bone-invasive cancer.

RESULTS

Calcium (Ca), which is high in healthy bone, is replaced by potassium (K) and sodium (Na) in bone-invasive cancer. The degree of stromal induction is significantly correlated with the discriminatory power between healthy and tumorous spectra. In this study, LIBS ensured an overall sensitivity of 95.51% and a specificity of 98.64% via the intracellular detection of K and Na.

CONCLUSION

This study demonstrated robust real-time detection of bone-invasive oral cancer with LIBS, which may lay the foundation for establishing LIBS as a rapid bone analysis method. Further development of a LIBS-guided assessment of bone tumor resection margins might reduce the extent of bony resection without compromising oncologic safety.

Locoregional recurrence rate and disease-specific survival following marginal vs segmental resection for oral squamous cell carcinoma with mandibular bone invasion

BACKGROUND AND OBJECTIVES

To determine locoregional recurrence rate (LRR) and disease-specific survival (DSS) following marginal vs segmental mandibulectomy.

METHODS

Included were 210 patients, who had marginal or segmental mandibulectomy between 2000 and 2017. Marginal resection was performed when complete removal of the tumor was deemed feasible on the condition that at least 1 cm bone height of the inferior border of the mandible could be preserved. Segmental resection was performed in case less than 1 cm bone height of the mandible would remain. Clinical and histopathological data were collected from medical records. LRR and DSS were computed using Kaplan-Meier analysis. Cox-regression analysis was used to identify risk factors for LRR and DSS.

RESULTS

A total of 59 marginal and 151 segmental resections had been performed. There was no significant difference in 3- and 5-year LRR (P = .904) and no significant difference in 3- and 5-year DSS (P = .362) between the marginal and segmental resection group. Cox-regression analysis showed a trend for surgical margin less than equal to 1 mm, to affect LRR (P = .05) and surgical margin less than equal 1 mm, perineural invasion and lymph node metastasis to affect DSS (P < .05).

CONCLUSIONS

There was no difference in outcome between the two types of mandibulectomy.

A Novel RNA-Seq-Based Model for Preoperative Prediction of Lymph Node Metastasis in Oral Squamous Cell Carcinoma

Objective

To develop and validate a novel RNA-seq-based nomogram for preoperative prediction of lymph node metastasis (LNM) for patients with oral squamous cell carcinoma (OSCC).

Methods

RNA-seq data for 276 OSCC patients (including 157 samples with LNM and 119 without LNM) were downloaded from TCGA database. Differential expression analysis was performed between LNM and non-LNM of OSCC. These samples were divided into a training set and a test set by a ratio of 9 : 1 while the relative proportion of the non-LNM and LNM groups was kept balanced within each dataset. Based on clinical features and seven candidate RNAs, we established a prediction model of LNM for OSCC using logistic regression analysis. Tenfold crossvalidation was utilized to examine the accuracy of the nomogram. Decision curve analysis was performed to evaluate the clinical utility of the nomogram.

Results

A total of 139 differentially expressed RNAs were identified between LNM and non-LNM of OSCC. Seven candidate RNAs were screened based on FPKM values, including NEURL1, AL162581.1 (miscRNA), AP002336.2 (lncRNA), CCBE1, CORO6, RDH12, and AC129492.6 (pseudogene). Logistic regression analysis revealed that the clinical N stage (p < 0.001) was an important factor to predict LNM. Moreover, three RNAs including RDH12 (p value < 0.05), CCBE1 (p value < 0.01), and AL162581.1 (p value < 0.05) could be predictive biomarkers for LNM in OSCC patients. The average accuracy rate of the model was 0.7661, indicating a good performance of the model.

Conclusion

Our findings constructed an RNA-seq-based nomogram combined with clinicopathology, which could potentially provide clinicians with a useful tool for preoperative prediction of LNM and be tailored for individualized therapy in patients with OSCC.