Prognostic performance of TNM8 staging rules in oral cavity squamous cell carcinoma

A Novel Risk Model for Predicting Dysphagia after Tongue Reconstruction: A Retrospective Multicenter Study in Japan

BACKGROUND

There is no consensus on the postoperative outcomes of tongue reconstruction. Therefore, the authors developed a novel risk model for predicting dysphagia after tongue reconstruction.

METHODS

This retrospective study was conducted by the Oral Pharyngeal Esophageal Operation and Reconstruction Analytical, or OPERA, group across 31 cancer centers and university hospitals in Japan. A total of 532 patients [390 (73.3%) men and 142 (26.7%) women; median age at surgery, 60 years (range, 15 to 88 years)] who were diagnosed with oral tongue squamous cell carcinoma and underwent tongue reconstruction following glossectomy between 2009 and 2013 were included. Independent risk factors were identified using univariate regression analysis and converted to a binary format for multivariate analysis. An integer value was assigned to each risk factor to calculate a total score capable of quantifying the risk of feeding tube dependence.

RESULTS

Overall, 54 patients (10.2%) required a feeding tube at the time of evaluation. Predictive factors for feeding tube dependence were advanced age, lower American Society of Anesthesiologists physical status, low body mass index, lower serum albumin, comorbid hypertension and diabetes, extended tongue defect, resection beyond the tongue, laryngeal suspension, postoperative radiation therapy, and no functional teeth. In multivariate logistic regression analysis, age greater than or equal to 58.5 years, postoperative radiation therapy, wider tongue defect, and body mass index less than 21.27 kg/m 2 earned 6, 4, 3, and 2 points, respectively, for a maximum total score of 15.

CONCLUSION

The authors' risk model provides a mathematical tool for estimating the individual risk of postoperative feeding tube dependence before tongue reconstruction.

CLINICAL QUESTION/LEVEL OF EVIDENCE

Risk, III.

Limits and potential implementation of the present pN classification for oral squamous cell carcinoma

PURPOSE OF REVIEW

The purpose of this review is to highlight the most important changes in the eighth TNM classification system for oral squamous cell carcinomas compared with the seventh edition with focus on lymph node staging (pN). Nodal involvement is crucial when addressing prediction of survival, and staging must mirror the disease extension. pN classification will be evaluated with respect to lymph node yield (LNY), lymph node density (LND), and a recently proposed classification: pN-N+ reflecting positive regional lymph nodes (metastatic burden) and extra nodal extension.

RECENT FINDINGS

TNM8 was introduced in 2018, and the most noteworthy changes were depth of invasion (DOI) and extranodal extension (ENE). Recent studies indicate, that TNM8-related pN is not superior to TNM7 with respect to predicting survival. LNY and LND are biased with ecological interference fallacy, and currently not recommended in future iterations of TNM. In contrast, the pN-N+ classification has demonstrated improved survival prediction compared with TNM8.

SUMMARY

The recent findings support the inclusion of pN-N+, that is, metastatic burden and extranodal extension in future iterations of TNM.

Peroxiredoxins-The Underrated Actors during Virus-Induced Oxidative Stress

Enhanced production of reactive oxygen species (ROS) triggered by various stimuli, including viral infections, has attributed much attention in the past years. It has been shown that different viruses that cause acute or chronic diseases induce oxidative stress in infected cells and dysregulate antioxidant its antioxidant capacity. However, most studies focused on catalase and superoxide dismutases, whereas a family of peroxiredoxins (Prdx), the most effective peroxide scavengers, were given little or no attention. In the current review, we demonstrate that peroxiredoxins scavenge hydrogen and organic peroxides at their physiological concentrations at various cell compartments, unlike many other antioxidant enzymes, and discuss their recycling. We also provide data on the regulation of their expression by various transcription factors, as they can be compared with the imprint of viruses on transcriptional machinery. Next, we discuss the involvement of peroxiredoxins in transferring signals from ROS on specific proteins by promoting the oxidation of target cysteine groups, as well as briefly demonstrate evidence of nonenzymatic, chaperone, functions of Prdx. Finally, we give an account of the current state of research of peroxiredoxins for various viruses. These data clearly show that Prdx have not been given proper attention despite all the achievements in general redox biology.

TNM 8 staging is a better prognosticator than TNM 7 for patients with locally advanced oral cavity squamous cell carcinoma treated with surgery and post-operative radiotherapy

PURPOSE

To assess TNM 8 staging in discriminating overall survival (OS) amongst patients with locally advanced oral cavity squamous cell carcinoma (OCSCC) treated with surgery and post-operative radiotherapy (PORT), compared to TNM 7.

MATERIAL AND METHODS

Data from OCSCC patients treated with surgery and PORT between January 2010 and December 2018 were reviewed. Demographics, tumour characteristics and treatment response data were collected, and patients staged according to both TNM 7 and TNM 8. OS and disease free survival (DFS) were estimated using the Kaplan Meier method. Univariate and multivariable analyses were conducted for factors affecting OS, DFS and early disease recurrence within 12 months.

RESULTS

Overall 172 patients were analyzed. Median follow up was 32 months for all patients and 48 months for surviving patients. TNM 8 staging demonstrated significant stratification of OS and DFS amongst the entire cohort, whereas TNM 7 staging did not. On multivariable analysis, TNM 8 stage, performance status (PS) and a positive surgical margin were prognostic for OS. Looking at disease recurrence within 12 months, TNM 8 stage IVB, presence of lymphovascular invasion (LVSI), younger age and lesser smoking history were predictive factors on multivariable analysis.

CONCLUSION

TNM 8 is a good development of its predecessor in terms of predicting survival for patients with locally advanced OCSCC. We have also identified younger age (<60 years) and a smoking history of <10 pack years as risk factors for early disease recurrence, potentially representing a separate biological cohort within OCSCC patients.

Metrics of pN-staging in oral squamous cell carcinoma: An analysis of 1,905 patients

BACKGROUND

We aimed to compare the predictive performance of pN-categories in oral squamous cell carcinoma (OSCC) encompassing the most recent 8th edition (TNM8), its predecessor (TNM7), and a newly proposed algorithm (pN-N⁺), which classifies patients according to the number of positive lymph nodes and extranodal extension.

METHODS

Consecutive, primary OSCC patients from seven previously published cohorts were included and classified according to the three pN-classifications: TNM7, TNM8 and pN-N⁺. Overall survival probabilities were summarised with the Kaplan-Meier method. We added each of the three metrics to a Cox regression adjusted for pT-category, lymph nodal yield, age, sex, radiotherapy and chemotherapy, and trained these models in one institution. We evaluated the predictive performance in the remaining six institutions and assessed the predicted 5-year risk of death using the area under the receiver operating characteristics curve (AUC) and Brier scores.

RESULTS

All 1,905 included patients were classified according to TNM7 and pN-N⁺. A subset of 1,575 patients was additionally classified according to TNM8, leading to upstaging in 27.0%. The pN-N⁺ ranked overall best determined by the obtained AUC and Brier scores. In contrast to pN-N⁺, TNM7 and TNM8 both suffered from disproportionate patient distribution across pN-categories and poor pN-categorial discrimination on overall survival.

CONCLUSIONS

The TNM8 pN-classification designates a larger subset to more advanced disease stages but failed to show improvement of its predictive performance compared to TNM7. The pN-categories of TNM7/8 are disproportionate and inconsistently discriminated. The pN-N⁺ conveyed the best measures of prognosis and should be considered in future TNM iterations.