The Impact of Peritumoral Retraction Clefting & Intratumoral Eosinophils on Overall Survival in Oral Squamous Carcinoma Patients.

This retrospective study aimed to investigate the impact of peritumoral retraction clefts (RC) and tumor-associated tissue eosinophilia (TATE) as predictors of overall survival (OS) in oral squamous cell carcinoma (OSCC) patients. Their relationships with tumor-factors were also examined. Eighty-seven OSCC cases (pTNM: I + II/III + IV; 32/55), post-curative surgery, comprised the study cohort. Three observers independently estimated the percent RC semi-quantitatively in the selected tumor sections. Additionally, stromal eosinophils were counted in ten consecutive high-power fields of intratumoral and peritumoral regions to evaluate the corresponding TATE. The percent RC ranged between 0% -90% (Mean ± SD: 16 ± 24%; Median: 5%). The stromal eosinophils were greater in peritumoral as compared to intratumoral region. The events of death and tumor recurrence were reached in 16 (18.4%) and 36 (41%) cases respectively. The 3-years OS was 69% [Median OS: 1880 days; Mean follow up: 471(Range; 36-1880) days]. Increased percent RC exhibited relationship with pathologic stage (pTNM III&IV), primary tumor (pT III&IV), tumor depth > 4 mm and categorical tumor recurrence. Additionally, peritumoral eosinophilic infiltrates increased with increasing tumor depths and muscle invasion. Kaplan-Meier curves revealed significantly reduced OS in OSCC cases exhibiting: increased percent RC (>2.5%), mild -moderate/absent intratumoral TATE (versus intense TATE) or categorical tumor recurrence. In subsequent multivariate tests, all the three variables retained significance. Additionally, intraclass correlation coefficient demonstrated acceptable internal consistency for the observers who estimated percent RC. In conclusion, RC and intratumoral TATE proved to be independent predictors of OS in our OSCC cohort. Additionally, increased percent RC pointed towards aggressive tumor behaviour.

A semi-quantitative World Health Organization grading scheme evaluating worst tumor differentiation predicts disease-free survival in oral squamous carcinoma patients.

We investigated World Health Organization (WHO) grading and pattern of invasion based histological schemes as independent predictors of disease-free survival, in oral squamous carcinoma patients. Tumor resection slides of eighty-seven oral squamous carcinoma patients [pTNM: I&II/III&IV-32/55] were evaluated. Besides examining various patterns of invasion, invasive front grade, predominant and worst (highest) WHO grade were recorded. For worst WHO grading, poor-undifferentiated component was estimated semi-quantitatively at advancing tumor edge (invasive growth front) in histology sections. Tumor recurrence was observed in 31 (35.6%) cases. The 2-year disease-free survival was 47% [Median: 656; follow-up: 14-1450] days. Using receiver operating characteristic curves, we defined poor-undifferentiated component exceeding 5% of tumor as the cutoff to assign an oral squamous carcinoma as grade-3, when following worst WHO grading. Kaplan-Meier curves for disease-free survival revealed prognostic association with nodal involvement, tumor size, worst WHO grading; most common pattern of invasion and invasive pattern grading score (sum of two most predominant patterns of invasion). In further multivariate analysis, tumor size (>2.5cm) and worst WHO grading (grade-3 tumors) independently predicted reduced disease-free survival [HR, 2.85; P=0.028 and HR, 3.37; P=0.031 respectively]. The inter-observer agreement was moderate for observers who semi-quantitatively estimated percentage of poor-undifferentiated morphology in oral squamous carcinomas. Our results support the value of semi-quantitative method to assign tumors as grade-3 with worst WHO grading for predicting reduced disease-free survival. Despite limitations, of the various histological tumor stratification schemes, WHO grading holds adjunctive value for its prognostic role, ease and universal familiarity.