Features and prognostic utility of biopsy in oral squamous cell carcinoma

Prediction of prognosis in oral squamous cell carcinoma using infrared microspectroscopy

BACKGROUND

Estimation of prognosis of oral squamous cell carcinoma (OSCC) is inaccurate prior to surgery, only being effected following subsequent pathological analysis of the primary tumour and excised lymph nodes. Consequently, a proportion of patients are overtreated, with an increase in morbidity, or undertreated, with inadequate margins and risk of recurrence. We hypothesise that it is possible to accurately characterise clinical outcomes from infrared spectra arising from diagnostic biopsies. In this first step, we correlate survival with IR spectra derived from the primary tumour.

METHODS

Infrared spectra were collected from tumour tissue from 29 patients with OSCC and subject to classification modelling.

RESULTS

The model had a median AUROC of 0.89 with regard to prognosis, a median specificity of 0.83, and a hazard ratio of 6.29 in univariate Cox proportional hazard modelling.

CONCLUSION

The data suggest that FTIR spectra may be a useful early biomarker of prognosis in OSCC.

Oral cancer: changing the aim of the biopsy in the age of precision medicine. A review

Oral cancer is a heterogeneous disease that develops through a complex, multi-step process. Precision medicine should help to better understand its molecular basis, integrate traditional classifications and have a positive impact on cancer management. To apply this information in clinical practice, we need to define its histology and identify biomarkers expressed by the tumour that provide useful information for planning tailored treatment. The most reliable information currently derives from evaluation of biomarkers on post-operative samples. To plan personalised treatment, oncologists need to assess these markers on biopsy samples. We reviewed the recent literature and identified 6 of 184 publications that compared markers measured on biopsy and post-operative samples or assessed their predictivity for the development of lymph node metastases. Data from these studies suggest that markers measured on biopsy samples can provide useful indications for tailoring treatments. However, due to their heterogeneity and low level of evidence, these results need to be confirmed by clinical studies on a large population to standardise and validate biomarkers in biopsies and to assess their reliability in other diagnostic mini-invasive procedures such as radiomics and liquid biopsy.

Biopsy quality is essential for preoperative prognostication in oral tongue cancer

A role for incisional biopsy in preoperative prognostication is increasingly being advocated in oral tongue squamous cell carcinomas (OTSCC). Biopsies at two locations were compared, and prognostic factors in biopsies and their corresponding resections were evaluated. A total of 138 OTSCC biopsy slides from Finland and Saudi Arabia were compared for size (horizontal and vertical) and invasive front. The Finnish cases were assessed for tumor stroma ratio (TSR) and tumor-infiltrating lymphocytes (TILs) using light microscopy and digital image analysis assessment and compared. Furthermore, TSR, TILs, and previously analyzed budding and depth of invasion (BD) score in biopsies were compared with their evaluation in the corresponding resections. Fifty-nine percent of Finnish and 42% of Saudi Arabian biopsies were ≥ 5 mm deep, while 98% of Saudi Arabian and 76% of Finnish biopsies were ≥ 5 mm wide. Assessment of invasion front was possible in 72% of Finnish in comparison with 40% of Saudi Arabian biopsies. There was 86.8% agreement between TSR and 75% agreement between TIL evaluation using light microscopy and digital assessment. Significant agreement was obtained on comparing the TSR (p = 0.04) and BD (p < 0.001) values in biopsies and resections. Biopsies of ≥ 5 mm depth from representative OTSCC areas are essential for prognostic information. Clinical pathologists are advised to assess BD score and TSR for prognostic features in such biopsies.

Can morphological features evaluated in oral cancer biopsies influence in decision-making? A preliminary study

Tumor budding (TB) is a promising prognostic marker in many cancers including oral squamous cell carcinoma. The evaluation of TB in preoperative diagnostic biopsies has been proven be possible; therefore, the association of TB with other morphological features can represent an important aid in the previous treatment decision. This study aims to evaluate TB in oral squamous cell carcinoma (OSCC) biopsies, assessing its association with other morphological characteristics of the sample. A total of 56 cases of OSCC were investigated. In hematoxylin and eosin-stained slides, morphological features including histopathological grading and mode of invasion were evaluated in the deep invasive front. Moreover, immunohistochemistry was performed with anti-multi-cytokeratin antibody helping in the identification of TB, which was graded as low-intensity or no TB and high-intensity TB. Descriptive and bivariate analyses were performed, and the level of significance was set at 5%. The tongue was the most-affected site with 29 (51.7 %) tumors. The predominant mode of invasion (27-48.2 %) was by groups of neoplastic cells without clear boundaries. Of the cases investigated, 37 (66.1 %) were high-intensity TB, which was associated with the mode of invasion of the tumors (p < 0.05). All cases with the worst mode of invasion showed high-intensity TB. Preliminary results showed the potential of morphological features, such as TB and mode of invasion, evaluated in diagnostic specimens of OSCC, aiding in the treatment decision to select patients who could benefit from more-aggressive treatments.

Assessment of Tumor-infiltrating Lymphocytes Predicts the Behavior of Early-stage Oral Tongue Cancer

Tumor-infiltrating lymphocytes (TILs) have shown a promising prognostic value in many epithelial cancers. We sought to assess the prognostic value of TILs in a multicenter cohort of early oral tongue squamous cell carcinoma (OTSCC). The percentage of TILs was assessed on the surgical resection slides stained with hematoxylin and eosin. The assessment of TILs was performed in the stromal compartment and in the intraepithelial compartment (at the invasive front and at the center of the tumor). We followed the method that was described recently by the International Immuno-Oncology Biomarker Working Group for the assessment of TILs. A total of 308 cases from the 5 Finnish university hospitals and from A.C. Camargo Cancer Center, São Paulo, Brazil, were included. We found a promising prognostic value for stromal TILs at the invasive front in the multivariable analysis with a hazard ratio of 2.61 (95% confidence interval [CI], 1.77-3.83; P<0.001) for overall survival, 1.99 (95% CI, 1.07-3.69; P=0.040) for disease-specific survival, and 1.94 (95% CI, 1.14-3.29; P=0.020) for disease-free survival. In conclusion, evaluation of TILs is simple and can aid in identifying the high-risk cases of early OTSCC. The method introduced by the International Immuno-Oncology Biomarker Working Group can be used for standardized determination of TILs in early OTSCC.

Data Set for the Reporting of Oral Cavity Carcinomas: Explanations and Recommendations of the Guidelines From the International Collaboration of Cancer Reporting

The International Collaboration on Cancer Reporting is a nonprofit organization whose goal is to develop evidence-based, internationally agreed-upon standardized data sets for each cancer site for use throughout the world. Providing global standardization of pathology tumor classification, staging, and other reporting elements will lead to the objective of improved patient management and enhanced epidemiologic research. Carcinomas of the oral cavity continue to represent a significant oncologic management burden, especially as changes in alcohol and tobacco use on a global scale contribute to tumor development. Separation of oral cavity carcinomas from oropharyngeal tumors is also important, as management and outcome are quite different when human papillomavirus association is taken into consideration. Topics such as tumor thickness versus depth of invasion, pattern of invasive front, extent and size of perineural invasion, and margin assessment all contribute to accurate classification and staging of tumors. This review focuses on the data set developed for Carcinomas of the Oral Cavity Histopathology Reporting Guide, with discussion of the key elements developed for inclusion.