Proposal of a scoring system for predicting pathological risk based on a semiautomated analysis of whole slide images in oral squamous cell carcinoma

Prognostic Significance of Tumor-Stroma Ratio (TSR) in Head and Neck Squamous Cell Carcinoma: Systematic Review and Meta-Analysis

The management of head and neck squamous cell carcinoma (HNSCC) relies heavily on TNM staging and WHO histologic grading; however, in recent years, the analysis of prognostic markers expressed in the tumor stroma has gained attention. The tumor-stroma ratio (TSR) quantifies the proportion of tumor tissue relative to the surrounding stromal tissue; it is assessed with the percentage of stromal tissue within the tumor area, with a cutoff point of 50% being widely used to discriminate high-stroma cancer. In this systematic review and meta-analysis, we investigated the potential prognostic role of the TSR in HNSCC. After a literature screening, 24 studies dealing with the TSR and survival outcomes were included. The TSR showed a significant association with overall survival (OS) in both unadjusted and adjusted measures (RR 2.04, CI 1.57-2.65, p < 0.01; HR 2.36 CI 1.89-2.94, p < 0.00001), with an even stronger prognostic potential in oral cavity/oral tongue cancers (RR 2.44 CI 1.84-3.22, p < 0.00001). The TSR also showed prognostic value when dealing with cancer-specific survival and was associated with a reduction in disease-free survival (DFS). In particular, the TSR also retained its prognostic role in terms of DFS when specifically considering early-stage cancers in both unadjusted and adjusted analyses (RR 1.81 CI 1.57-2.10, p < 0.00001; HR 2.09 CI 1.58-2.76, p < 0.00001). Therefore, we conclude that the TSR is a reliable prognostic marker that is easy to assess in routine histological slides and can be effectively implemented in the routine evaluation of HNSCC.

Predictive value of tumor budding in head and neck squamous cell carcinoma: an update

Head and neck squamous cell carcinoma forms an anatomically and functionally complex group of malignancies. The significant local aggressiveness and frequent regional relapses motivate ongoing research to identify more reliable and sensitive prognostic and predictive biomarkers. One emerging area of cancer biology is the evaluation of tumor budding at the advancing invasive front of various types of epithelial cancers. Recent studies suggest that tumor budding is a relatively common phenomenon in cancer progression and that it may have important prognostic implications for patients due to its potential to provide valuable insights into the biology and clinical behavior of head and neck cancer. In this review, we aim to provide information about tumor budding in head and neck squamous cell carcinoma. Thus, we hope to shed light on the complex biology of these malignancies, as well as aiding diagnostic, classification, and better characterization and thereby, looking for new avenues for improving patient outcomes.

Tumor Budding and Poor Prognosis in Oral Cancer: A Systematic Review and Meta-Analysis

BACKGROUND

Tumor budding (TB) has been investigated in several types of solid tumors. In oral cancer, studies show its association with survival. However, for its implementation in routine histological analyses, results with a high certainty of evidence are needed. Therefore, the aim of this systematic review is to explore the association between tumor budding and overall survival (OS), disease-specific survival (DSS), and disease-free survival (DFS) in oral cancer.

METHODS

A search was performed in Embase, PubMed, Scopus, Livivo, Web of Science, and Google Scholar. We adopted the following inclusion criteria: studies that evaluate tumor budding in oral cancer, that investigate survival, and presenting cohort design. We excluded reviews and studies without hazard-ratio (HR) data.

RESULTS

This systematic review included 22 studies and showed an association between TB and survival. High-grade TB is associated with a worse OS in univariate analysis (HR = 3.11; 95% CI: 2.06-4.69, p<0.01) and multivariate analysis (HR = 2.62; 95% CI: 1.64-4.20, p<0.01); with a poorer DSS in univariate (HR = 2.43; 95% CI: 1.94-3.03, p<0.01) and multivariate analysis (HR = 2.01; 95% CI: 1.43-2.83, p< 0.01); and with a worse DFS in univariate (HR = 1.94; 95% CI: 1.44-2.62, p<0.01) and multivariate analysis (HR = 2.15; 95% CI: 1.31-3.53, p< 0.01). Sensitivity analysis showed that the results are robust, and no significant publication bias was identified in univariate analysis for DFS (Egger's test: p = 0.94). The certainty of the evidence was graded as low or very low.

CONCLUSION

Our findings indicate that TB is an independent prognostic factor of OS, DSS, and DFS in oral cancer. However, further studies are needed to increase the certainty of the evidence.

Artificial Intelligence for Image Analysis in Oral Squamous Cell Carcinoma: A Review

Head and neck tumor differential diagnosis and prognosis have always been a challenge for oral pathologists due to their similarities and complexity. Artificial intelligence novel applications can function as an auxiliary tool for the objective interpretation of histomorphological digital slides. In this review, we present digital histopathological image analysis applications in oral squamous cell carcinoma. A literature search was performed in PubMed MEDLINE with the following keywords: "artificial intelligence" OR "deep learning" OR "machine learning" AND "oral squamous cell carcinoma". Artificial intelligence has proven to be a helpful tool in histopathological image analysis of tumors and other lesions, even though it is necessary to continue researching in this area, mainly for clinical validation.

Multiperspective quantitative tumor-stroma ratio reveals histological areas associated with poor outcomes in oral squamous cell carcinoma

AIMS

Different regions of oral squamous cell carcinoma (OSCC) have particular histopathological characteristics, and the individual histological characteristics of the tumors are poorly understood. Therefore, calculating the proportion of tumor cells in different regions that allow assessment of the prognostic outcomes for OSCC patients would be of great clinical significance.

METHODS AND RESULTS

We established an open-source software-based analytic pipeline that defines the inner tumor and invasive tumor front (ITF) in pancytokeratin-stained whole slide images (WSIs) and quantifies the tumor-stroma ratio (TSR) within the two regions. We applied this method to 114 patients with OSCC and predicted patient prognosis by the TSR. The proportion of tumor area in the inner tumor was generally higher than that in the ITF (p < 0.0001). TSR was an independent prognostic factor for overall survival (OS) (p = 0.016), disease-free survival (DFS) (p = 0.026), and relapse-free survival (RFS) (p = 0.037) in inner tumor, and TSR was an independent prognostic factor for OS (p = 0.00052), DFS (p = 0.035), and metastasis-free survival (MFS) (p = 0.038) in the ITF. Tumor-low status was associated with poorer prognosis. There was a significant correlation between the TSR and perineural invasion (PNI) in the inner tumor (p = 0.009).

CONCLUSIONS

The histopathological characteristics of different regions of OSCC may be used to develop the potential prognostic markers. The TSR of the inner tumor is more targeted in predicting prognosis and accurately assesses the risk of PNI+.

The Emerging Impact of Tumor Budding in Oral Squamous Cell Carcinoma: Main Issues and Clinical Relevance of a New Prognostic Marker

Tumor Budding (TB) represents a single cancer cell or a small cluster of less than five cancer cells on the infiltrative tumor front. Accumulating evidence suggests TB is an independent prognostic factor in oral squamous cell carcinoma (OSCC). However, its exact role is not yet elucidated, and a standardized scoring system is still necessary. The study aims to extensively review the literature data regarding the prognostic role of TB in OSCC. The results of TB are an independent prognostic factor of poor survival outcomes in OSCC. To date, the manual detection of hematoxylin and eosin-staining or pancytokeratin-immunostaining sections are the most commonly used methods. Between the several cut-offs, the two-tier system with five buds/field cut-offs provides better risk stratification. The prognostic role of the BD model in predicting survival outcomes was extensively validated; however, the inclusion of DOI, which is already a staging parameter, encouraged other authors to propose other models, integrating TB count with other adverse risk factors, such as the tumor–stroma ratio and tumor-infiltrated lymphocytes. The prognostic relevance of TB in OSCC highlights its evaluation in daily pathological practice. Therefore, the TB detection method and the TB scoring system should be validated based on tumor stage and site.

Prognostic significance of tumor budding thresholds in oral tongue squamous cell carcinoma

Oral tongue squamous cell carcinoma (OTSCC) represents the most common malignancy of the oral cavity. Tumor budding (TB) is a reliable prognostic factor in OTSCC; however, a standardized scoring system is not still validated. The study aims to evaluate the prognostic role of TB in 211 OTSCC patients treated between 1997-2018. TB was evaluated on haematoxylin and eosin-stained sections in the hotspot area of the infiltrative front (×200-magnification). It was scored using a two-tier, a three-tier system, and according to BD-model and revised-Grading system. Univariate and multivariate Cox regression analyses of disease-specific survival (DSS) and disease-free survival (DFS) were performed. A p-values<0.05 was considered as statistically significant. The two-tier and three-tier system resulted an independent prognostic factor of DSS. High-risk patients had a 2.21 and 3.08 times-increased probability of poor DSS compared to low-risk group. It is significantly increased even for intermediate-risk group. No significant differences emerged classifying patients according to BD-model and revised-Grading. These data confirm the prognostic value of TB in predicting DSS in OTSCC. Classifying patients in two groups using the 5-buds cut-off significantly discriminates their outcomes. Since the established role of DOI and the poor prognostic value of grading, TB could be considered an independent prognostic marker.

Tumor-Infiltrating Lymphocytes in Head and Neck Cancer: Ready for Prime Time?

The evaluation of tumor-infiltrating lymphocytes (TILs) has received global attention as a promising prognostic cancer biomarker that can aid in clinical decision making. Proof of their significance was first shown in breast cancer, where TILs are now recommended in the classification of breast tumors. Emerging evidence indicates that the significance of TILs extends to other cancer types, including head and neck cancer. In the era of immunotherapy as a treatment choice for head and neck cancer, assessment of TILs and immune checkpoints is of high clinical relevance. The availability of the standardized method from the International Immuno-oncology Biomarker Working Group (IIBWG) is an important cornerstone toward standardized assessment. The aim of the current article is to summarize the accumulated evidence and to establish a clear premise for future research toward the implementation of TILs in the personalized management of head and neck squamous cell carcinoma patients.

Proposal of a scoring system for predicting pathological risk based on a semiautomated analysis of whole slide images in oral squamous cell carcinoma

BACKGROUND

The study aimed to evaluate the risk factors based on pathological findings comprehensively in oral squamous cell carcinoma (OSCC) using image analysis.

METHODS

Scanned images of hematoxylin and eosin-, pan-cytokeratin-, CD3-, and CD8-stained slides of OSCC cases from 256 patients were analyzed, and six variables were obtained including the tumor-stroma ratio, tumor budding per tumor bed area, and tumor infiltrating lymphocytes-associated variables. We determined the "score" of all cases based on the variables, and all cases were classified into low-, intermediate-, and high-risk groups.

RESULTS

A significant difference in prognosis was confirmed between the risk groups (p < 0.001), and even when evaluated within different tumor-node-metastasis (TNM) stages, the high-risk groups were associated with poor survival.

CONCLUSIONS

We report our work on a possible descriptive model that can predict prognosis based on pathological and imaging findings regardless of the TNM stage.