Background: To implement the new marker in clinical practice, reliability assessment, validation, and standardization of utilization must be applied. This study evaluated the reliability of tumor-infiltrating lymphocytes (TILs) and tumor-stroma ratio (TSR) assessment through conventional microscopy by comparing observers’ estimations. Methods: Intratumoral and tumor-front stromal TILs, and TSR, were assessed by three pathologists using 86 CRC HE slides. TSR and TILs were categorized using one and four different proposed cutoff systems, respectively, and agreement was assessed using the intraclass coefficient (ICC) and Cohen’s kappa statistics. Pairwise evaluation of agreement was performed using the Fleiss kappa statistic and the concordance rate and it was visualized by Bland–Altman plots. To investigate the association between biomarkers and patient data, Pearson’s correlation analysis was applied. Results: For the evaluation of intratumoral stromal TILs, ICC of 0.505 (95% CI: 0.35–0.64) was obtained, kappa values were in the range of 0.21 to 0.38, and concordance rates in the range of 0.61 to 0.72. For the evaluation of tumor-front TILs, ICC was 0.52 (95% CI: 0.32–0.67), the overall kappa value ranged from 0.24 to 0.30, and the concordance rate ranged from 0.66 to 0.72. For estimating the TSR, the ICC was 0.48 (95% CI: 0.35–0.60), the kappa value was 0.49 and the concordance rate was 0.76. We observed a significant correlation between tumor grade and the median of TSR (0.29 (95% CI: 0.032–0.51), p-value = 0.03). Conclusions: The agreement between pathologists in estimating these markers corresponds to poor-to-moderate agreement; implementing immune scores in daily practice requires more concentration in inter-observer agreements.

This case reveals the complexities and challenges in the diagnosis of acute Epstein-Barr virus (EBV) infection, indicating the potential relationship between EBV infection and severe icteric hepatitis, acalculous cholecystitis, and lymphocytic vasculitis. We suggest including EBV infectious mononucleosis in the list of differential diagnoses when any of these clinical syndromes (or a combination thereof) occurs without apparent cause, especially in the presence of lymphocytosis. To our knowledge, this is the first report to suggest the possible role of EBV in the pathogenesis of cutaneous lymphocytic vasculitis. Also it is possible that EBV infection triggered the flare-up of the underlying rheumatologic disease. Therefore, it could be assumed that a part of the clinical syndrome (e.g., dermatologic manifestations) might be related to the flare-up of the underlying rheumatologic disease.