Turkish Journal of Pathology最新文献

< strong > Objective: < /strong > Medullary thyroid carcinoma (MTC) is a rare tumor originating from parafollicular C cells. It has more aggressive biologic behavior than differentiated thyroid carcinomas, and it is insensitive to treatment with radioactive iodine. Vandetanib and cabozantinib are the newly approved tyrosine kinase inhibitors in advanced stages, but novel effective systemic therapeutics could be crucial and needed for the clinical management of these patients. We aimed to evaluate the Programmed death-ligand 1 (PD-L1) expression, which is a novel immunotherapy target, in our MTC cohort, and determine whether it has an association with clinical and pathological features. < strong > Material and Method: < /strong > This retrospective study involved 41 cases of MTC with a median follow-up of 54 months. PD-L1 monoclonal antibody (SP263 clone) was investigated immunohistochemically. Complete and/or partial membranous staining pattern in more than 1% of tumor cells was considered positive. The correlations of PD-L1 expression with clinicopathologic and prognostic features were analyzed. < strong > Results: < /strong > PD-L1 positivity was detected in 5 (12.2%) of 41 tumors. The extent of PD-L1 staining was low ( < 5%) for all tumors. There was no clinicopathologic and prognostic relevance regarding PD-L1 expression in our MTC patients. < strong > Conclusion: < /strong > Although PD-L1 expression could be a potential biomarker to predict the prognosis of various cancers and response to checkpoint inhibitors, we did not find any significant correlation between PD-L1 expression and clinicopathologic features in our cases. Studies with larger patient numbers are still required to perform a more comprehensive analysis.

Objective: Ependymomas are neuroepithelial tumors of the central nervous system with heterogeneous biology and clinical course. The aim of the present study is to investigate the relationship between the methylation status and clinicopathological parameters in ependymomas.

Material and method: DNA methylation status of CDKN2A, RASSF1A, KLF4 and ZIC2 genes were quantitatively analyzed with pyrosequencing in 44 ependymoma tumor tissues. The relationship of methylation profiles with tumor subtype, histological grade and patient age was statistically analyzed.

Results: DNA methylation analyses for CDKN2A revealed no difference in methylation levels. Of the 31 included samples for optimal ZIC2 methylation analysis, 10 were hypermethylated (32.3%) and this change was significantly found in the adult spinal ependymomas (p=0.01). KLF4 hypermethylation was observed in 6 of the overall included 35 samples (17.1%); however, there was no statistically significant relation of the methylation status with tumor subtype, histological grade or age group. RASSF1A hypermethylation was observed in overall 40 included samples with varying methylation levels. Higher levels of hypermethylation were significantly related to the grade 3 histology (p=0.01) and spinal ependymomas (p=0.006). The pediatric cases with grade 3 ependymomas and ependymomas of adulthood showed significantly increased RASSF1A hypermethylation levels (p < 0.001 and p=0.001, respectively).

Conclusion: DNA methylation changes are likely to have biological importance in ependymomas. Both ZIC2 and RASSF1A methylation status may be useful parameters in the subclassification of these tumors.

Objective: Tumors belonging to the mixed epithelial stromal tumor family (MESTF) are rare; thus clinicopathological experience about them are limited. Each epithelial and stromal component shows different patterns in these tumors.

Material and method: Clinicopathological features of 11 MESTF cases that were diagnosed between 2000 and 2021 at a single center were evaluated.

Results: Ten of the 11 patients were female (F:M = 10:1). The mean age of the females was 47 (31-63) years; the male patient was 45 years old. The mean tumor diameter was 6.7 (3.5-19) cm. All tumors had varying proportions of cystic and solid components. Eight cases were well circumscribed, and the others had distinct but irregular borders. Two of the tumors with irregular borders were bulging into the renal sinus. The epithelial component was dominant in most cases. In the epithelial component, macrocyst, microcyst, and tubules were the most common patterns and the most common types of lining epithelium were flat, cuboidal and hobnail. The stromal component was variable in most cases and included hypocellular (mostly collagenous) and cellular areas. In most cases, the cellular stroma had an ovarian-like appearance. Among the other features observed, hyalinization and dystrophic calcification were common. The positivity for estrogen and progesterone receptor in the stromal component was observed in almost all female cases.

Conclusion: MESTF, which has distinctive features, should be considered in the differential diagnosis of cystic kidney tumors.

Objective: While the presence and number of metastatic lymph nodes (LNs) are important prognostic factors for pancreatic ductal adenocarcinoma (PDAC), there is no recommendation to specify metastatic regional LN localization in the current staging system. The aim of this study was to evaluate the prognostic effect of regional metastatic LN localizations in PDAC.

Material and method: Metastatic sites of 101 consecutive PDAC patients who underwent pancreaticoduodenectomy were classified as peripancreatic, perigastric, hepatica communis, hepatoduodenal, and superior mesenteric artery. The frequency of metastasis in each region and the association between the presence of metastasis in each site and overall and disease-free survival were statistically analyzed.

Results: Eighty cases (79.2%) had peripancreatic, 7 (6.9%) had perigastric, 6 (5.9%) had hepatica communis, 7 (6.9%) had hepatoduodenal, and 4 (4%) had superior mesenteric artery LN metastasis. The overall and disease-free survival values were significantly shorter in patients with hepatoduodenal LN metastasis (log rank; p= 0.001, p=0.017, respectively). The presence of metastatic superior mesenteric artery LN was significantly associated with shorter disease-free survival in univariate analysis (p=0.017). Hepatoduodenal LN metastasis was an independent predictor of mortality (p=0.005) in multivariate analysis.

Conclusion: The presence of hepatoduodenal LN metastasis is an independent poor prognostic factor for mortality. The presence of metastatic LN in the superior mesenteric artery region was significantly associated with shorter disease-free survival time, although not an independent predictor. We conclude that the metastatic regional LN sites, especially the hepatoduodenal region, have an impact on the prognosis, and should be included in synoptic pathology reports.

Granular cell tumours are uncommon acquired benign tumours of nerve sheath origin that are usually seen in the head and neck region and upper aero-digestive tract. They usually present as solitary small sized nodules in middle age. The tumour is usually benign and composed of sheets of large sized cells with abundant granular cytoplasm containing lysosomal macro-inclusions known as pustulo-ovoid bodies of Milian (POB) that represent the heterogeneity of the lysosomes. No well-established criteria for malignancy have been described for this tumour. In this article, we have discussed a rare case of granular cell tumour of the penis with its characteristic histomorphology and immunohistochemistry and relevant differential diagnosis.

Objective: Intraoperative frozen section (IOFS) diagnosis of brain tumors plays an important role in assessing the adequacy of the sample and determining the treatment plan. The aim of this study was to investigate the diagnostic accuracy between IOFS and permanent sections.

Material and method: The authors reviewed the histopathological results of 383 brain tumors, including IOFS and permanent histological diagnosis. The cases were classified into three diagnostic compatibilities (i) Perfect fit; the diagnosis of IOFS was identical to the permanent diagnosis, (ii) Partial compatibility; IOFS diagnosis was not incorrect but was too broad to be considered full compatibility, (iii) Conflict; IOFS diagnosis is completely different from the permanent diagnosis. The permanent diagnosis was used as a primary criterion and was compared to IOFS diagnosis and recurrence rate using different statistical methods.

Results: 84% of the patients underwent craniotomy and tumor resection, while 15% only underwent tumor biopsy. Approximately, 53.8 % of the cases revealed perfect matching in the diagnosis between IOFSs and permanent sections, while 16.2% of the cases revealed complete mismatching in the diagnosis between the sections. The remaining 30% of the cases showed partial compatibility in the diagnosis between the two diagnostic methods. There was no significant difference in recurrence rate among all cases of different diagnostic compatibility (p=0.54).

Conclusion: There is a diagnostic discrepancy between IOFSs and permanent sections. However, cases that revealed no consensus in the diagnoses showed no negative effect on the patient outcome. Further studies should be conducted to explore the reasons of this conflict in the two diagnostic methods.

Objective: Microscopic colitis is a chronic inflammatory disorder characterized by a triad of chronic diarrhea, endoscopy without significant abnormality, and distinct histopathological features. Histopathologically, microscopic colitis is divided into 3 subtypes; collagenous colitis, lymphocytic colitis, incomplete microscopic colitis. The main purpose of this study was to analyze the detailed clinicopathological parameters of microscopic colitis cases in the Turkish population.

Material and method: The clinicopathological parameters were evaluated in 53 microscopic colitis cases (37 collagenous colitis, 7 lymphocytic colitis, 9 incomplete microscopic colitis) diagnosed between 2010 and 2019.

Results: All cases had lymphoplasmacytosis. The presence of ≥20 eosinophils/high power field in the lamina propria was remarkable in 75.7%, 57.1%, and 11.1% of collagenous colitis, lymphocytic colitis, and incomplete microscopic colitis cases, respectively. One of the striking findings was the presence of concomitant Celiac disease in 29% of the lymphocytic colitis cases. In terms of drug use, proton pump inhibitors and nonsteroidal anti-inflammatory drugs were the most commonly used drugs.

Conclusion: The mean age in our series is lower than the literature and a distinct male predominance was observed in lymphocytic colitis and incomplete microscopic colitis, contrary to the literature. These suggest that susceptibility to microscopic colitis may differ between ethnic groups. The presence of overt lymphoplasmacytosis, eosinophilic infiltration and epithelial damage are the microscopic features which should alert the pathologist for the diagnosis of complete microscopic colitis. Given that microscopic colitis is a common treatable cause of chronic diarrhea, awareness of the aforementioned histopathological features is of utmost importance for accurate diagnosis and not to miss incomplete cases.

Objective: The aim of this study was to evaluate programmed cell death ligand-1 (PD-L1) expression and the relationship between driver mutations and survival analysis in advanced-stage non-small cell lung carcinoma (NSCLC).

Material and method: A total of 122 advanced-stage NSCLC patients were included in this retrospective study. The patients were diagnosed based on cytological examination and histopathological analysis of biopsy or resection material that had undergone at least 1 molecular analysis. The expression of PD-L1 in tumors and tumor-infiltrating lymphocytes (TIL) was scored and compared with age, sex, organ, biopsy method, tumor subtype, driver mutation status, and overall survival data.

Results: There was no statistically significant difference between PD-L1-positivity and age, gender, location, pattern, or pathological diagnosis of the type of sample. When the threshold value for PD-L1 IHC evaluation was accepted as ≥1% and ≥50%, the rate of positivity was 19.7% and 7.4%, respectively.

Conclusion: Since there is a wide range of positivity rates reported in the literature, we could not reach a conclusion as to whether the PD-L1-positivity rate we observed was high or low. There is a need for comparative studies where the technique, clones, threshold values, and phases are homogenized. There is an inverse correlation between the EGFR-mutant population and PD-L1 positivity. In terms of overall survival, no relationship was found between PD-L1 positivity, the presence of TIL, and EGFR mutation status.

Objective: Our study investigated the morphological and immunohistochemical characteristics of invasive breast carcinoma of no special type (IBC-NST) with medullary pattern to explore the inconsistencies between the structural and clinical traits of this category of tumor.

Material and method: The breast carcinoma samples (n = 26) with medullary pattern (defined according to established criteria) were subjected to immunohistochemical assays of the following receptors: ER, PR, HER2/neu, Ki-67, p53, Bcl-2, VEGF, MMP1, E-cadherin, EGFR, Hsp70, Hsp90, CD20, CD3, CD4, CD8, CD68, CD163, CD56, CD138, MPO, S100, IgG, IgM, and PD-L1.

Results: IBC-NST with medullary pattern was found to have negative expression of ER, PR, and HER2/neu; strong positive expression of Kі-67, mutant р53, Bcl-2, E-cadherin, EGFR, and PD-L1; moderate positive expression of Hsp70 and Hsp90; and low or negative expression of VEGF and MMP1. Furthermore, there was pronounced variability in the qualitative composition of tumor immune infiltrates with regards to T-lymphocytes, B-lymphocytes, macrophages, plasmocytes, and granulocytes.

Conclusion: IBC-NST with medullary pattern has many unfavourable morphological and immunohistochemical prognostic characteristics, which are balanced against the pronounced protective properties of the tumor cells and the qualitative characteristics of the tumor microenvironment. These can lead to a favourable disease course despite the relatively adverse features of the carcinoma cells.