In this issue

Abstract

In a personalized medicine there is a continuous and strong need for novel therapeutics to efficiently treat advanced and aggressive cancer. Like in previous issues this issue also contains novel information on immune checkpoint inhibitor therapy as demonstrated on pancreatic carcinoma. Tahkola et al. (https://doi.org/10.1007/s00428-020-02888-4) studied the relationship between PD-L1 and CD73 expression by immunohistochemistry and found that CD73 expression in tumor cells was associated with poor survival independently from the number of tumor-infiltrating lymphocytes or TNM stage. In multivariate analysis, CD73 positivity in tumor cells was an independent negative prognostic factor together with histopathological grade, TNM stage and low immune cell score. Pan TRK immunohistochemistry is a helpful tool in screening for genomic alterations of TRK but there is still a strong need for standardization and high quality. A robin round trial in Belgium published by de Winne et al. (https://doi.org/10. 1007/s00428-020-02921-6) tried to assess the quality of TRK analysis and found out that in 7 out of 10 labs the quality was good. The interpretation seems to be challenging in cases with physiological TRK expression. Minor steps of optimization helped to score well on technical staining and subsequent evaluation. Jiang et al. (https://doi.org/10.1007/s00428-020-02878-6) studied the clinical value of microsatellite instability (MSI) in gastric cancer and found MSI-low (L) as independent prognostic factor with respect to disease-free but not overall survival in the setting of neoadjuvant chemotherapy. MSI-L carcinomas responded poorly to chemotherapy and were associated with perineural invasion and decreased MUC5AC expression. Radonic et al. (https://doi.org/10.1007/s00428-020-02848-y) studied the influence of preanalytical factors on the performance of delta-like protein 3 (DLL3) immunohistochemistry which becomes increasingly important for pulmonary small cell carcinoma. They found that particularly the selection of the proper fixative and fixation time are crucial for optimal staining results. In stage II colon carcinoma adjuvant chemotherapy is only used for cases with increased risk of metastasis and recurrence. Ammendola et al. (https://doi.org/10.1007/ s00428-020-02880-y) investigated the influence of tumor budding (TB) and poorly differentiated tumor cell clusters (PDC) on disease specific survival in patients without adjuvant chemotherapy. Both high TB grade and PDC were associated with decreased disease specific survival but only the latter remained statistically significant in multivariate analysis and might be considered as an additional high-risk factor in the therapeutic selection. Ragazzi et al. (https://doi.org/10.1007/s00428-020-028919) investigated anaplastic thyroid carcinomas for their putative origin from associated well differentiated tumor components by immunohistochemistry and next generation sequencing. They found a progressive accumulation of mutations in the anaplastic tumor component with conservation of the mutations present in the well differentiated component supporting the hypothesis of a progression from the differentiated to the anaplastic tumor. This is further accompanied by changes in the immunoreactive profile. Ishida et al. (https://doi.org/10.1007/s00428-020-02865-x) studied the impact of p16 expression in squamous and small cell esophageal carcinoma which seems to be induced through an inactivation of RB1 signaling pathway but not through HPV infection which was not detected in any of the included tumors. Notably, p16 expression was strongly associated with small cell carcinoma but infrequent in squamous cell carcinoma and without prognostic impact in the latter. Moreira et al. (https://doi.org/10.1007/s00428-020-028688) studied the value of Ki-67 as adjunct marker in the evaluation and differential diagnosis of well differentiated hepatocellular neoplasms. Ki-67 seems to be helpful in the distinction between well differentiated hepatocellular carcinoma and hepatic adenoma since “hot spot” proliferative rates are consistently very low in hepatic adenoma but vary significantly in well differentiated hepatocellular carcinoma. Waidhauser et al. (https://doi.org/10.1007/s00428-02002884-8) studied the clinical value of autopsies in the clinical setting and found particularly in in 50% of the oncological cases major discrepancies between the clinical cause of death and the post-mortem findings. They concluded https://doi.org/10.1007/s00428-020-03001-5