Analysis of clinicopathological risk factors for locoregional recurrence of oral squamous cell carcinoma – Retrospective analysis of 517 patients

Oncological outcomes of the facial artery musculomucosal flap for oral cavity reconstruction

BACKGROUND

Facial artery musculomucosal (FAMM) flaps are used for reconstruction of oral cavity squamous cell carcinoma (OCSCC). This study evaluates the oncologic safety of the FAMM flaps for OCSCC reconstruction, given the need to preserve the facial artery and vein during elective neck dissection.

DESIGN & METHODS

Retrospective single surgeon case series of all patients undergoing FAMM flap reconstruction for OCSCC from 2016 through 2023. Case analysis included tumor location, classification and staging, surgical details, and post-operative outcomes including locoregional and overall disease control.

RESULTS

Twenty-one patients underwent FAMM reconstruction after resection for OCSCC. Age ranged from 40 to 85 years old (mean 61), 15 (71 %) were male. Sixteen (76 %) patients underwent neck dissection. Follow-up ranged from 0 to 81 months (mean 28). One patient (5 %) recurred in ipsilateral neck level IV, one (5 %) had a second primary tumor, and three patients (14 %) developed distant metastases.

CONCLUSIONS

FAMM flap represents a safe and reliable option for reconstruction after OCSCC. In our series there was no significant increased risk of locoregional recurrence.

The Prognostic Value of Preoperative Total Cholesterol in Surgically Treated Oral Cavity Cancer

BACKGROUND

With growing evidence linking lipid profile changes to tumor development and cancer prognosis, we investigated the prognostic significance of preoperative serum total cholesterol (TC) levels in patients with oral cavity squamous cell carcinoma (OSCC) undergoing surgical treatment.

METHODS

We conducted a retrospective observational study involving 310 patients with primary OSCC who received surgery at our hospital from January 2009 to December 2018. Receiver operating characteristic curve analysis was performed to determine the optimal preoperative TC cutoff value, with the Youden Index employed as the optimization criterion to maximize the sum of sensitivity and specificity. Variables with p < 0.1 in the univariable analysis were included in the multivariable Cox regression model, and stepwise selection was used to identify the optimal subset of prognostic factors for overall survival (OS) and disease-free survival (DFS).

RESULTS

An optimal TC cutoff of 157 mg/dL was established. Patients with TC < 157 mg/dL exhibited significantly lower 5-year rates of OS and DFS (p < 0.001 and p = 0.006, respectively). Multivariable analysis confirmed that TC < 157 mg/dL represented an independent prognostic factor for reduced OS and DFS rates. Subgroup analyses reinforced the consistent prognostic significance of TC. We also constructed a nomogram (concordance index: 0.74) to provide personalized OS predictions, enhancing the clinical utility of TC.

CONCLUSIONS

Preoperative TC appears to be a significant prognostic factor for OS and DFS after OSCC surgery. Routine TC assessment facilitates the development of nomograms for personalized survival predictions, supports clinicians in tailoring treatment strategies, and guides nutritional or metabolic interventions to enhance patient outcomes. Further multicenter prospective studies are needed to validate our findings.

The epidemiological and histopathological factors for delayed local recurrence in oral squamous cell carcinoma

BACKGROUND

Oral squamous cell carcinoma (OSCC) is a prevalent malignancy in oral cancer. Approximately 26% of OSCC cases recur after initial curative treatment, with over 80% of these recurrences occurring within the first 2 years. Delayed local recurrence (DLR) occurring beyond the 2-year period in cases of OSCC is infrequent. The aim of this study is to investigate the histopathological characteristics associated with DLR.

METHODS

This study included 197 patients diagnosed with OSCC who underwent primary surgery from 2006 to 2022. Epidemiological features, such as age and gender, and histopathological features, including primary tumor sites, TNM staging, histopathological grading, depth of invasion, the presence of lymphovascular or perineural invasion, and the utilization of radiation therapy (RT) and neck dissection (ND) were analyzed.

RESULTS

The mean interval until local recurrence was 22 ± 27 months. There were 10 cases of DLR (20.83%) among 51 patients with local recurrence. The epidemiological and histopathological analysis of these cases is as follows: 10 patients (3 males and 7 females) aged 51-80 years (median, 56.5 years). Primary tumor sites were tongue (n = 3), maxillary gingiva (n = 1), mandibular gingiva (n = 3), retromolar trigone (n = 1), and buccal mucosa (n = 2). Tumor size was advanced (T3/T4) in 5 cases, while a smaller size (T1/T2) was observed in 5 cases. No lymph node metastasis was 80.0%. Histopathological grading was well differentiated in 9 cases and moderately differentiated in 1 case, with no cases of poorly differentiated tumors. Depth of invasion > 5 mm was 70.0% of the cases (n = 7). Lymphovascular invasion and perineural invasion were not present. Three patients received RT, and 8 patients underwent ND. There were 2 patients who consumed alcohol, and 2 patients who smoked tobacco. The results showed that histological differentiation had a significant relationship with the interval (p = 0.031).

CONCLUSIONS

DLR, occurring more than 2 years after the initial tumor resection surgery, is infrequent. Histological differentiation is associated with tumor recurrence intervals. Patients with a higher histological grading require more precise follow-up observation during the initial 2 years after surgery.

Web-based prognostic tools for oral tongue cancer: An analysis of online predictors

BACKGROUND

Oral tongue squamous cell carcinoma (OTSCC) often presents with aggressive clinical behaviour that may require multimodality treatment based on reliable prognostication. We aimed to evaluate the prognostic ability of five online web-based tools to predict the clinical behaviour of OTSCC resection and biopsy samples.

METHODS

A total of 135 OTSCC resection cases and 33 OTSCC biopsies were included to predict recurrence and survival. Area under the receiver operating characteristic curves (AUC), χ2 tests, and calibration plots constructed to estimate the prognostic power of each tool.

RESULTS

The tool entitled 'Prediction of risk of Locoregional Recurrences in Early OTSCC' presented an accuracy of 82%. The tool, 'Head & Neck Cancer Outcome Calculator' for 10-year cancer-related mortality had an accuracy 77% and AUC 0.858. The other tool entitled 'Cancer Survival Rates' for 5-year mortality showed an accuracy of 74% and AUC of 0.723. For biopsy samples, 'Cancer Survival Prediction Calculators' predicted the recurrence free survival with an accuracy of 70%.

CONCLUSIONS

Web-based tools can aid in clinical decision making of OTSCC. Three of five online web-based tools could predict recurrence risk and cancer-related mortality in resected OTSCC and one tool could help in clinical decision making for biopsy samples.

Recurrent Versus Metastatic Head and Neck Cancer: An Evolving Landscape and the Role of Immunotherapy

Squamous cell carcinoma of the head and neck (SCCHN) is among the ten most common cancers worldwide, with advanced SCCHN presenting with a 5-year survival of 34% in the case of nodal involvement and 8% in the case of metastatic disease. Disease-free survival at 2 years is 67% for stage II and 33% for stage III tumors, whereas 12-30% of patients undergo distant failures after curative treatment. Previous treatments often hinder the success of salvage surgery and/or reirradiation, while the standard of care for the majority of metastatic SCCHN remains palliative chemo- and immuno-therapy, with few patients eligible for locoregional treatments. The aim of this paper is to review the characteristics of recurrent SCCHN, based on different recurrence sites, and metastatic disease; we will also explore the possibilities not only of salvage surgery and reirradiation but also systemic therapy choices and locoregional treatment for metastatic SCCHN.

Comprehensive survival analysis of oral squamous cell carcinoma patients undergoing initial radical surgery

OBJECTIVE

This study was designed to evaluate the five-year overall survival (OS) rate and postoperative survival time of patients diagnosed with oral squamous cell carcinoma (OSCC), as well as examine the clinical and pathological factors influencing survival outcomes in OSCC patients.

METHODS

Data were collected from OSCC patients who underwent their first radical surgical intervention in the Department of Maxillofacial Surgery at the First Affiliated Hospital of Chongqing Medical University between April 2014 and December 2016. Follow-up was conducted until March 2022.

RESULTS

The study included a total of 162 patients. The observed 5-year OS rate was 59.3%. Approximately 45.7% of OSCC patients experienced postoperative recurrence or metastasis, with a 5-year overall disease-free survival rate of 49.4%. There was no significant difference in the impact of sex, age, smoking, alcohol consumption, primary tumour location, depth of invasion or primary tumour size on the 5-year survival rate (p > 0.05). Univariate analysis revealed that clinical stage (Hazard Ratio = 2.239, p = 0.004), perineural invasion (PNI) (Hazard Ratio = 1.712, p = 0.03), lymph node metastasis (pN) (Hazard Ratio = 2.119, p = 0.002), pathological differentiation (Hazard Ratio = 2.715, p < 0.001), and recurrence or metastasis (Hazard Ratio = 10.02, p < 0.001) were significant factors influencing survival. Multivariate analysis further indicated that pathological differentiation (Hazard Ratio = 2.291, p = 0.001), PNI (Hazard Ratio = 1.765, p = 0.031) and recurrence or metastasis (Hazard Ratio = 9.256, p < 0.001) were independent risk factors of survival. Intriguingly, 11 OSCC patients were diagnosed with oesophageal squamous cell carcinoma (ESCC) within 1-4 years following surgery.

CONCLUSION

The survival prognosis of OSCC patients is significantly associated with clinical stage, PNI, lymph node metastasis, pathological differentiation, and recurrence or metastasis. Pathological differentiation, PNI and recurrence or metastasis are independent risk factors affecting survival. Routine clinical screening for ESCC may be recommended for OSCC patients with a history of alcohol consumption and tobacco use.

Addition of tumor microenvironment immune cell composition to improve the performance of a predictive model for oral squamous cell carcinoma

BACKGROUND

Conventional clinicopathological characteristics insufficiently predict prognosis in oral squamous cell carcinoma (OSCC). We aimed to assess the added predictive value of tumor microenvironment immune cell composition (TMICC) in addition to conventional clinicopathological characteristics.

METHODS

Primary tumor samples of 290 OSCC patients were immunohistochemically stained for CD4, CD8, CD20, CD68, CD163, CD57, FoxP3 and Programmed cell Death Ligand 1. Additionally, clinicopathological characteristics were obtained from patients' medical files. Predictive models were trained and validated by conducting Least Absolute Shrinkage and Selection Operator (LASSO) regression analyses with cross-validation. To quantify the added predictive power of TMICC within models, receiver operating characteristic (ROC) analyses were used.

RESULTS

Recurrence occurred in 74 patients (25.5%). Conventional clinicopathological characteristics (tumor localization, pathological T-stage, pathological N-stage, extracapsular spread, resection margin, differentiation grade, perineural invasion, lymphovascular invasion) and treatment modality, were used to build a LASSO logistic regression-based predictive model. Addition of TMICC to the model resulted in a comparable AUC of respectively 0.79 (±0.01) and 0.76 (±0.1) in the training and test sets. The model indicated that high numbers of CD4+ T cells protected against recurrence. Lymph node metastasis, extracapsular spread, perineural invasion, positive surgical margins and reception of adjuvant treatment were associated with increased risk for recurrence.

CONCLUSIONS

The TMICC, specifically the number of CD4+ T cells, is an independent predictor , however, addition to conventional clinicopathological characteristics does not improve the performance of a predictive model for recurrence in OSCC.

Improved recurrence rates and progression-free survival in primarily surgically treated oral squamous cell carcinoma - results from a German tertiary medical center

OBJECTIVES

This study aimed to explore survival and recurrence patterns in patients undergoing primarily surgical treatment for oral squamous cell carcinoma (OSCC) at a high-volume tertiary medical center in Germany.

MATERIALS AND METHODS

The study included 421 patients with primary OSCC who underwent radical tumor resection, neck dissection, and reconstruction with a free flap. Prognostic relevance of clinicopathological characteristics was assessed using Cox proportional-hazards models. Kaplan-Meier method estimated local recurrence-free survival, progression-free survival (PFS), and overall survival (OS), while the log-rank test compared survival outcomes between groups.

RESULTS

Recurrence manifested in 16.63% of the patients (70 patients), encompassing local recurrence in 54 patients (77.14%) and distant metastasis in 24 patients (34.28%). Neck recurrence occurred in only 1 patient (0.24%) on the contralateral side. The majority of recurrences occurred within the initial twelve months following primary tumor surgery (64.29%). Overall, the 5-year OS stood at 58.29%, while the 5-year PFS reached 72.53%. Patients with early recurrence within ≤ 12 months showed the least favorable prognosis (log-rank, all p < 0.001).

CONCLUSIONS

Our findings show a significant decrease in recurrence rates and enhanced PFS at a high-volume tertiary medical center in Germany compared to previous studies. Local recurrence was the primary form observed, with most recurrences happening within the initial twelve months post-surgery. Opting for treatment at a high-volume center and devising therapy plans in interdisciplinary tumor boards may not only enhance OS but also contribute to improved PFS.

CLINICAL RELEVANCE

These findings offer valuable insights for physicians regarding the post-treatment care of patients with OSCC. The results underscore the importance of frequent follow-up appointments, particularly during the initial year, and highlight the critical need for vigilance in monitoring for local recurrence.

Predicting recurrence in oral cavity cancers: a review of 116 patients with buccal mucosa carcinoma in northwestern India

BACKGROUND

Oral cavity cancers, the second most common type in India, are responsible for 10% of the overall cancer burden. With a recurrence rate of 30% to 40% and a 5-year survival rate of 50%, these malignancies account for substantial morbidity and mortality. Despite advances in treatment modalities, survival rates following treatment completion have not improved significantly. The present study aimed to establish specific epidemiological and pathological factors responsible for recurrence after treatment completion in buccal mucosa cancers.

METHODS

A retrospective analysis of the data of 116 patients treated for biopsy-proven cancers of the buccal mucosa was undertaken 1 year after treatment completion. Factors such as age, sex, education, lymphovascular invasion, extranodal extension (ENE), perineural invasion, depth of invasion, and pathological margin status were compared between patients who presented with recurrence and those who did not. Statistical significance was set at p< 0.05.

RESULTS

Of the 116 patients, 40 (34.5%) developed a recurrent disease within 1 year. The mean age of the study population was 43.3 years, and males constituted 91.4% of the included patients. Ipsilateral buccal mucosa was the commonest site of disease recurrence. Neck node metastasis, ENE, and margins of resection < 5 mm were significantly related to the recurrence of disease. However, surprisingly, lymphovascular invasion, perineural invasion, and depth of invasion > 10 mm did not show statistically significant associations.

CONCLUSION

Neck node metastasis, ENE, and margins of resection < 5 mm were the histopathological factors associated with recurrence in cancers of the buccal mucosa.

Temporal and spatial patterns of recurrence in oral squamous cell carcinoma, a single-center retrospective cohort study in China

BACKGROUND

Oral squamous cell carcinoma (OSCC) is an invasive cancer with a high recurrence rate. Most clinical studies have focused on the prognosis of patients with OSCC, few have investigated the causes and interventions that affect the recurrence. Our study is to explore the temporal and spatial patterns of recurrence in OSCC.

METHODS

234 OSCC patients with recurrence in our hospital and 64 OSCC patients with recurrence in TCGA database were included in the study. Log-rank test and Multivariate Cox Regression Analysis were used to determine whether there was a significant difference between each selected demographic or clinical factors and recurrence. The Kaplan-Meier method was used to plot survival curves for each recurrence interval.

RESULTS

The proportion of OSCC patients in clinical and TCGA with early recurrence was 93.6% and 84.4%, respectively. Age, chewing betel nut, previous radiotherapy, histopathological grading of the primary tumor (poorly differentiated), lymph node metastasis and postoperative infection were found to be associated with the timing of recurrence. It was found that tongue cancer has more regional recurrences, while buccal cancer is mostly local and loco-regional recurrences. The earlier the recurrence, the greater the possibility of local-regional recurrence and the worse the prognosis.

CONCLUSION

Most of recurrent OSCC patients present early recurrence (< 18 months) with poor prognosis, and early recurrence is more prone to local recurrence. Moreover, recurrence site is related with primary site of OSCC.

Beyond Traditional Approaches: A Pilot Study Exploring the Role of Injection Mitomycin C on the Surgical Resection Bed in Oral Cancer Treatment

Background Oral cavity cancer ranks sixth among all cancers worldwide. India has the most oral cancer cases and accounts for one-third of the global oral cancer burden. Oral cavity cancer is known to be associated with an elevated likelihood of locoregional recurrences, which account for the bulk of post-surgery and radiotherapy treatment failures. Mitomycin C (MMC) is an antineoplastic and antibiotic agent that is administered topically rather than intravenously to treat bladder and intraperitoneal tumors to avoid recurrences. This study aimed to investigate the use of injection MMC as a local application on surgical resection beds for patients undergoing surgery for oral cancer and to assess its efficacy in preventing regional recurrences. Methodology In this prospective, interventional, pilot study, patients were assigned randomly to two groups using simple randomization. Group A involved the application of two gauze pieces soaked with MMC injection. Group B involved the application of two gauze pieces soaked with a 10% betadine solution. During the pectoralis major myocutaneous flap harvest procedure for reconstruction, two gauze pieces soaked with either injection MMC solution (20 mg MMC in 20 mL of 0.9% normal saline) or 10% betadine solution were placed on the surgical resection bed for a 45-minute contact period. Patients were evaluated daily in the postoperative period for local complications. Regular follow-up visits were scheduled for 15 months of follow-up. Results After exclusions at various phases, the final analysis included 50 patients in Group A and 50 patients in Group B. Minor complications, specifically blackening of the skin flap in the neck resulting in surgical site infections, were observed in 16% (eight patients) of the MMC group and in 6% (three patients) of the betadine group (p = 0.1997) patients. In the MMC group, two (4%) patients experienced locoregional recurrences at three months, four (8%) patients at six months, six (12%) patients at nine months, eight (16%) patients at 12 months, and 10 (20%) patients at 15 months of follow-up. In contrast, locoregional recurrences occurred in two (4%) patients in the betadine group at three months, six (12%) patients at six months, nine (18%) patients at nine months, 12 (24%) patients at 12 months, and 15 (30%) patients at 15 months. Although the difference in locoregional recurrences between the two groups was not statistically significant, there was a trend of decreasing locoregional recurrences in the MMC group relative to the betadine group as the duration of follow-up increased. In the subgroup analysis of patients with pathological extranodal extension (ENE), only 10 of 18 patients with ENE in Group A (55.55%) experienced a recurrence, whereas all 12 patients with ENE in Group B (100%) experienced a recurrence within the same time frame. This difference in locoregional recurrence rates between the two groups was statistically significant, with a p-value of 0.0100. Conclusions Our study demonstrated that the local administration of MMC on surgical resection beds may lower the risk of locoregional recurrences in patients with oral cancer, especially those with ENE. These findings contribute to the ongoing efforts to enhance treatment strategies and patient outcomes for this challenging malignancy.

Development of a Machine Learning Model to Predict Recurrence of Oral Tongue Squamous Cell Carcinoma

Despite diagnostic advancements, the development of reliable prognostic systems for assessing the risk of cancer recurrence still remains a challenge. In this study, we developed a novel framework to generate highly representative machine-learning prediction models for oral tongue squamous cell carcinoma (OTSCC) cancer recurrence. We identified cases of 5- and 10-year OTSCC recurrence from the SEER database. Four classification models were trained using the H₂O ai platform, whose performances were assessed according to their accuracy, recall, precision, and the area under the curve (AUC) of their receiver operating characteristic (ROC) curves. By evaluating Shapley additive explanation contribution plots, feature importance was studied. Of the 130,979 patients studied, 36,042 (27.5%) were female, and the mean (SD) age was 58.2 (13.7) years. The Gradient Boosting Machine model performed the best, achieving 81.8% accuracy and 97.7% precision for 5-year prediction. Moreover, 10-year predictions demonstrated 80.0% accuracy and 94.0% precision. The number of prior tumors, patient age, the site of cancer recurrence, and tumor histology were the most significant predictors. The implementation of our novel SEER framework enabled the successful identification of patients with OTSCC recurrence, with which highly accurate and sensitive prediction models were generated. Thus, we demonstrate our framework's potential for application in various cancers to build generalizable screening tools to predict tumor recurrence.

Oral Squamous Cell Carcinomas Developing from Oral Lichen Planus: A 5-21 year Retrospective Study

Background and Aims

There is insufficient data regarding clinical characteristics, relapse rates, as well as lymph node metastasis of squamous cell carcinomas of the oral cavity (OSCC) developing from oral lichen planus (OLP-OSCC). The aim of this retrospective study was to evaluate clinical characteristics, as well as relapse, recurrence and survival rates of OLP-OSCC.

Methods

In a retrospective monocenter analysis, all consecutive patients with an OSCC treated in the time period 1st January 2000-December 31 2016 were reviewed. All patients with OSCC developing from OLP/OLL (oral lichenoid lesions) were identified and analyzed for epidemiological data, risk profile, location of primary tumor, pTNM classification, lymph node metastasis, primary therapy, recurrence, and outcome.

Results

A total of 103 patients (45%♂/ 55%♀) with an average age of 62 ± 14 year were included in this study. At the time of initial diagnosis, 17% (n = 18) of patients had cervical metastases (CM) whereas only 11% (11 patients) displayed advanced tumor sizes (T > 2). T-status (p = 0.003) and histopathological grading (p = 0.001) had an impact on the incidence of CM. 39.6% of the patients developed a relapse after an average of 24 months with a mean of two recurrences per patient. Advanced tumor size had a significant impact on the 5 year overall survival and was associated with disease-free survival of the patients (p < 0.001, respectively p = 0.004).

Conclusion

Although initial lymph node metastases were not more frequent, more aggressive recurrence patterns compared to OSCC were seen for OLP-OSCC. Therefore, based on the study results, a modified recall for these patients is suggested.

Tumor Recurrence and Follow-Up Intervals in Oral Squamous Cell Carcinoma

Tumor recurrence in oral squamous cell carcinoma (OSCC) is frequent. However, no consensus about follow-up interval is available. The aim of this study was to analyze the recurrence pattern, detection method and associated parameters for possible risk stratification. Histopathological and epidemiological features were obtained retrospectively and correlated with tumor recurrence and overall survival, distant and lymph node metastases. A total of 760 patients were included, of which 216 patients showed tumor recurrence (mean after 24 ± 26 months). Within the first 12 months, 24% of the recurrences were detected. The primary detection method was clinical examination (n = 123, 57%). Tumor recurrence significantly correlated with advanced histopathological grading (G2/3 vs. G1, p < 0.000) and lymph node metastasis (p = 0.004). Tumor recurrence was frequent. Clinical examination was the primary detection method and manifestation within the first 6−12 months was high. The degree of histopathological grading may be useful for risk stratification.

Time to Recurrence Associated With Poor Prognosis in Japanese Oral Squamous Cell Carcinoma Patients

Purpose

Recurrence in oral squamous cell carcinoma (OSCC) is not rare. Due to lack of studies assessing characteristics of recurrent OSCC, including time to recurrence and outcomes, we sought to investigate its characteristics, time to recurrence, and outcomes in Japanese OSCC patients.

Methods

This study was a nonrandomized retrospective cohort study in a tertiary referral centre. It included 208 (117 men and 91 women) patients with recurrent oral cancer who underwent major curative surgery in the Department of Oral and Maxillofacial Surgery at Kobe University Hospital between January 1999 and April 2017. The outcomes were disease-specific survival (DSS) and overall survival (OS).

Results

In multivariable Cox proportional hazards analysis, the time to recurrence (hazard ratio [HR] 3.55, 95% confidence interval [CI] 1.69-6.63; P = 0.001), extranodal extension (ENE, HR 2.72, 95% CI 1.51-4.89; P = 0.001), and high T stage (HR 2.00, 95% CI 1.01-3.97; P = 0.046) were independent predictors of DSS. The time to recurrence (HR 3.29, 95% CI 1.82-5.96; P < 0.001) and ENE (HR 2.64, 95% CI 1.52-4.56; P = 0.001) were independent predictors of OS.

Conclusion

Time to recurrence, extranodal extension, and higher T stage were independent prognosis predictors in OSCC.

The budding and depth of invasion model in oral cancer: A systematic review and meta-analysis

BACKGROUND

Tumour budding (B) and depth of invasion (D) have both been reported as promising prognostic markers in oral squamous cell carcinoma (OSCC). This meta-analysis assessed the prognostic value of the tumour budding and depth of invasion combination (BD model) in OSCC.

METHODS

Databases including Ovid MEDLINE, PubMed, Scopus and Web of Science were searched for articles that studied the BD model as a prognosticator in OSCC. PICO search strategy was "In OSCC patients, does BD model have a prognostic power?" We used the reporting recommendations for tumour marker prognostic studies (REMARK) criteria to evaluate the quality of studies eligible for systematic review and meta-analysis.

RESULTS

Nine studies were relevant as they analysed the BD model for prognostication of OSCC. These studies used either haematoxylin and eosin (HE) or pan-cytokeratin (PCK)-stained resected sections of OSCC. Our meta-analysis showed a significant association of BD model with OSCC disease-free survival (hazard ratio = 2.02; 95% confidence interval = 1.44-2.85).

CONCLUSIONS

The BD model is a simple and reliable prognostic indicator for OSCC. Evaluation of the BD model from HE- or PCK-stained sections could facilitate individualized treatment planning for OSCC patients.

Is F-18 FDG PET/computed tomography a useful tool to restage the patients with tongue carcinoma?

OBJECTIVE

The aim of this study was to evaluate the diagnostic performance of contrast-enhanced F-18 fluoro-2-deoxyglucose (F-18 FDG) PET/computed tomography (CT) in restaging of tongue carcinoma.

MATERIAL AND METHODS

Retrospectively analysis of carcinoma tongue patients (n = 110) who were treated and referred for FDG PET/CT. Histopathological examination and clinical or imaging follow-up were taken as gold standard.

RESULTS

Of 110 patients, FDG PET/CT detected FDG avid lesions in 69 (62.7%) patients. Sensitivity, specificity and diagnostic accuracy of FDG PET/CT were 92.9%, 90.0% and 91.8%, respectively, for residual/recurrence disease detection (P < 0.05). Additionally, in six patients, metachronous primaries were also detected [lung (4), esophagus and lymphoma (1) each]. The mean maximum standardized uptake value (SUVmax) with 95% confidence interval for primary site recurrence, regional lymph nodes and metastatic lesions was 11.51 (9.53-13.48), 69 (62.7%) (7.88-11.48) and 8.94 (3.11-14.76), respectively.

CONCLUSION

FDG PET/CT demonstrates high diagnostic accuracy for detection of residual/recurrent disease in treated tongue cancer patients and PET/CT should be considered as first-line diagnostic investigation in these patients.

Registration of magnetic resonance and computed tomography images in patients with oral squamous cell carcinoma for three-dimensional virtual planning of mandibular resection and reconstruction

The aim of this study was to evaluate and present an automated method for registration of magnetic resonance imaging (MRI) and computed tomography (CT) or cone beam CT (CBCT) images of the mandibular region for patients with oral squamous cell carcinoma (OSCC). Registered MRI and (CB)CT could facilitate the three-dimensional virtual planning of surgical guides employed for resection and reconstruction in patients with OSCC with mandibular invasion. MRI and (CB)CT images were collected retrospectively from 19 patients. MRI images were aligned with (CB)CT images employing a rigid registration approach (stage 1), a rigid registration approach using a mandibular mask (stage 2), and two non-rigid registration approaches (stage 3). Registration accuracy was quantified by the mean target registration error (mTRE), calculated over a set of landmarks annotated by two observers. Stage 2 achieved the best registration result, with an mTRE of 2.5±0.7mm, which was comparable to the inter- and intra-observer variabilities of landmark placement in MRI. Stage 2 was significantly better aligned compared to all approaches in stage 3. In conclusion, this study demonstrated that rigid registration with the use of a mask is an appropriate image registration method for aligning MRI and (CB)CT images of the mandibular region in patients with OSCC.

Survival outcomes after surgical treatment of oral squamous cell carcinoma

OBJECTIVE

To identify the clinicopathological parameters that influence survival in patients with oral squamous cell carcinoma, in order to allow for the development of individualized surveillance programmes and reduce the delay in diagnosis of recurrence.

MATERIALS AND METHODS

Retrospective chart review of 553 patients with a treatment-naïve primary oral squamous cell carcinoma, who underwent primarily curative intended surgery. Exclusion criteria were neoadjuvant radio(chemo)therapy, follow-up < 1 year, perioperative death, inoperable disease, synchronous multiple malignancies and inadequate information on clinicopathological parameters.

RESULTS

The clinicopathological factors that influence overall survival, disease-free survival and locoregional control were calculated. In the multivariate survival analysis, the occurrence of recurrence, presence of extracapsular spread, T- and N-classification were shown to be independent risk factors for overall survival.

CONCLUSION

The identification of these risk factors can lead to the development of individualized follow-up programmes based on risk stratification. This allows for the earliest possible diagnosis of relapse which is essential to offer the patient a realistic second treatment chance and to improve survival rates.

Comparison of supervised machine learning classification techniques in prediction of locoregional recurrences in early oral tongue cancer

BACKGROUND

The proper estimate of the risk of recurrences in early-stage oral tongue squamous cell carcinoma (OTSCC) is mandatory for individual treatment-decision making. However, this remains a challenge even for experienced multidisciplinary centers.

OBJECTIVES

We compared the performance of four machine learning (ML) algorithms for predicting the risk of locoregional recurrences in patients with OTSCC. These algorithms were Support Vector Machine (SVM), Naive Bayes (NB), Boosted Decision Tree (BDT), and Decision Forest (DF).

MATERIALS AND METHODS

The study cohort comprised 311 cases from the five University Hospitals in Finland and A.C. Camargo Cancer Center, São Paulo, Brazil. For comparison of the algorithms, we used the harmonic mean of precision and recall called F1 score, specificity, and accuracy values. These algorithms and their corresponding permutation feature importance (PFI) with the input parameters were externally tested on 59 new cases. Furthermore, we compared the performance of the algorithm that showed the highest prediction accuracy with the prognostic significance of depth of invasion (DOI).

RESULTS

The results showed that the average specificity of all the algorithms was 71% . The SVM showed an accuracy of 68% and F1 score of 0.63, NB an accuracy of 70% and F1 score of 0.64, BDT an accuracy of 81% and F1 score of 0.78, and DF an accuracy of 78% and F1 score of 0.70. Additionally, these algorithms outperformed the DOI-based approach, which gave an accuracy of 63%. With PFI-analysis, there was no significant difference in the overall accuracies of three of the algorithms; PFI-BDT accuracy increased to 83.1%, PFI-DF increased to 80%, PFI-SVM decreased to 64.4%, while PFI-NB accuracy increased significantly to 81.4%.

CONCLUSIONS

Our findings show that the best classification accuracy was achieved with the boosted decision tree algorithm. Additionally, these algorithms outperformed the DOI-based approach. Furthermore, with few parameters identified in the PFI analysis, ML technique still showed the ability to predict locoregional recurrence. The application of boosted decision tree machine learning algorithm can stratify OTSCC patients and thus aid in their individual treatment planning.

Time to recurrence and patient survival in recurrent oral squamous cell carcinoma

OBJECTIVES

Tumour relapse remains one of the major problems in managing oral squamous cell carcinoma (OSCC) with mortality rates of up to 92%. Early recurrences have a worse prognosis than late relapses. However, few has been written about the influence of clinicopathological parameters on the timing of recurrence and the patient survival.

MATERIALS AND METHODS

Retrospective chart review of 159 patients with an OSCC recurrent disease. Exclusion criteria were neoadjuvant chemoradiotherapy, follow-up <6 weeks, perioperative death, second primaries and inadequate information on clinicopathological parameters. Statistical analysis was performed using univariate and multivariate analysis.

RESULTS

A significant correlation was found in the χ2-analysis between the timing of recurrence and the margin status (p = 0.020), lymph node ratio (p = 0.030) and grading (p = 0.003) of the primary tumour. In the multivariate survival analysis, the timing of recurrence (p < 0.001), margin status of the primary tumour (p = 0.023), presence of extracapsular spread in the primary tumour (p = 0.003) and performance of a salvage treatment (p < 0.001) were shown to be independent risk factors for overall survival.

CONCLUSION

For patients with a recurrent OSCC, the time to recurrence, margin status, extracapsular spread and the performance of a salvage treatment are independent prognostic factors for overall survival. Furthermore, a significant association exists between the moment of recurrence and the lymph node ratio, the margin status and grading of the primary tumour. This knowledge can allow for the development of individualised surveillance programs and like this, an earlier diagnosis and better second treatment chance in the case of a recurrence.

Podoplanin expression in oral leukoplakia─a prospective study

PURPOSE

The aim of this prospective work was to examine oral leukoplakia for their podoplanin expression to determine whether podoplanin expression is associated with the degree of dysplasia.

MATERIALS AND METHODS

We took biopsy samples from 50 patients with oral leukoplakia in 2013. The preparations studied by immunohistochemistry were analyzed in correlation with the degree of dysplasia and other clinicopathological variables.

RESULTS

The Chi-square test showed a significant correlation between podoplanin expression and the degree of dysplasia according to the squamous intraepithelial neoplasia (SIN) classification (p = 0.033). Also, a significant association between age grouping and podoplanin expression was found. We were able to show that the distribution is the same for both age groups in relation to the score of podoplanin expression (p = 0.003).

CONCLUSION

In a comparable retrospective work of our working group, it could be shown that podoplanin is a reliable predictive marker for the assessment of the risk of malignant transformation. The present work was able to substantiate the assumption that podoplanin not only plays an important role in the context of malignant degeneration but also exerts a major influence in advance.

SUOX is negatively associated with multistep carcinogenesis and proliferation in oral squamous cell carcinoma

Oral squamous cell carcinoma (OSCC) is the most common malignant tumor in the head and neck region. The aim of this study was to identify the key molecules and to elucidate the molecular mechanisms of OSCC carcinogenesis through a microarray analysis of RNA extracted from normal epithelium, dysplasia, and squamous cell carcinoma components. Out of molecules that showed changes in gene expression in the microarray analysis, we focused on Sulfite oxidase (SUOX), which correlated significantly with carcinogenic process and exhibited a stepwise decrease in expression. The expression of SUOX was evaluated in detail at the protein level using samples from 58 patients with cancer of the tongue, and correlating clinicopathological factors were also comprehensively examined. SUOX expression declined significantly from normal epithelium to dysplasia to squamous cell carcinoma components in line with carcinogenic process. With regard to squamous cell carcinoma, SUOX expression was significantly lower when T classification was high. Our findings indicated that SUOX is negatively associated with the progression and proliferation of tongue cancer, and suggest that SUOX may be a key molecule in tongue tumors.