Clinicopathological and prognostic significance of PD-L1 expression in colon adenocarcinoma tumor budding.

OBJECTIVE: In this study, we investigated the relationship between programmed cell death ligand 1 (PD-L1) and programmed cell death protein 1 (PD-1) expression in colon adenocarcinoma tumor budding. METHODS: This study included 122 patients with colon adenocarcinomas. The largest sample of formaldehyde-fixed paraffin-embedded tumor tissues was selected for analysis. Expression of membranous PD-L1 (clone 22C3) and the Combined Positive Score (CPS) in tumor tissues was calculated and graded according to the percentages of peritumoral and intratumoral tumor cells (0 %, 1 %, 1-5 %, >5 %). The effects of these factors on the prognosis were analyzed. RESULTS: Tumor budding was associated with adverse clinicopathological features and poor overall survival. PD-L1 (CPS%) peritumoral tumor budding (1 %/<1 %) was statistically significant in the univariate model (p = 0.004). Age, organ metastases (liver, lung, liver, lung, and peritoneum), and metastases were statistically significant in the multivariate model (p = 0.001, p = 0.004, p = 0.001, p = 0.002, p = 0.004, and p = 0.032, respectively). PD-L1 positive staining was mostly observed around the tumor and during tumor budding. PD-L1 peritumoral tumor budding rates and patients' survival rates differed significantly (log-rank = 12.07, p = 0.007). CONCLUSION: We found that patients with PD-L1 (CPS%) > 1 % in tumor budding had a shortened life expectancy and demonstrated the importance of including tumor budding areas in the samples used for biomarker evaluation. We previously reported that PD-L1 expression in tumor budding is associated with more aggressive cancer biology and poor survival, although overall survival is of limited statistical significance.

Evaluation of Formalin-fixed Paraffin-embedded Tissue Samples Diagnosed by Histopathology as Echinococcus in Çorum

Objective: This study aimed to detect the presence of Echinococcus spp. in formalin-fixed paraffin-embedded (FFPG) samples of hydatid cyst cases and to discuss the DNA isolation problems in FFPG samples. Methods: FFPG samples of 47 cases diagnosed with hydatid cyst were included in this study. Demographic characteristics of the cases were investigated. Microtome sections were taken from the samples and deparaffinization, DNA extraction, polymerase chain reaction (PCR), and gel agarose electrophoresis procedures were performed. Results: Of the cases, 55.3% were female, whereas 45.7% were male. Average age was 45.47 and 68.1% of the cases were located in the liver, 17.0% in the lung, 12.8% in the abdomen, and 2.1% in the brain. DNA was obtained in only 11 (23.4%) of the FFPG cyst samples and no proliferation was detected in the PCR products of any of the sample. Conclusion: The scolex/germinal membrane' absence in the FFPG sections, intense inflammatory cell reaction, presence of fibrosis and stromal/parenchymal tissue, DNA damage due to formaldehyde action, long-term archiving, and insufficient amount of DNA obtained were considered as factors preventing DNA replication in PCR.

Clinical and pathological significance of programmed cell death 1 (PD-1)/programmed cell death ligand 1 (PD-L1) expression in high grade serous ovarian cancer.

We investigated programmed cell death 1 (PD-1) / programmed cell death ligand 1 (PD-L1) expression in high grade serous ovarian cancer (HGSOC) and its relationship to tumor infiltrating lymphocytes (TIL) and prognosis. Formalin fixed paraffin embedded (FFPE) samples of 94 HGSOC cases were included in the study. Immunohistochemical analysis (CD3, CD4, CD8, PD-1 and PD-L1) was performed. Samples were analyzed for expression of immune proteins in the peritumoral stromal and intratumoral areas, scored, and expression was correlated with overall survival, stage, and age. PD-L1 staining ratio with a score greater than 0 was found to have lower survival. There were two positive staining patterns, patchy/diffuse and patchy/focal patterns, in 24 (25.5%) cases. Considering the threshold value ≥5%, we demonstrated that the PD-L1 positive cancer cell membrane immunoreactivity rate and patchy/diffuse PD-L1 expression were 9.6% (n = 9). There was statistically significant relationship between high PD-1 scores and PD-L1 cases of ≥ 5%. A statistically significant difference was found between PD-L1 staining and survival in patients with a threshold ≥ 5%. However an appropriate rate for treatment was determined in 9.6% cases. There was a statistically significant correlation between PD-1 positive TIL score and intratumoral CD3, peritumoral stromal CD3, intratumoral CD4 and intratumoral CD8 positive cells. Survival was lower in cases with higher PD-L1 positive stromal TIL score.