Lipoblastomatosis is a rare benign adipocytic tumour of infancy and early childhood, characterized by rapid growth. Diagnosis is challenging, owing to tumour heterogeneity and overlap with other pediatric soft-tissue neoplasms. PLAG1 rearrangement is the defining molecular hallmark, with an expanding list of fusion partners. We report a case of a 1-year-old child with a firm, nonmobile mass in the right thigh, which on CECT was deep-seated and heterogeneously enhanced. Gross evaluation of the excision specimen demonstrated an ill-circumscribed soft tissue mass. Histopathologically, the tumour showed myxoid nodules with primitive mesenchymal spindle-cell areas, and peripheral adipose tissue containing scattered lipoblasts, features suggestive of lipoblastomatosis. The IHC study showed S100 and CD34 positivity in adipocytes, and desmin and myogenin positivity in spindle-cell components. Molecular testing by NGS revealed a COL1A2::PLAG1 gene fusion, thus further establishing the diagnosis. Differentials such as myxoid liposarcoma, fibrous hamartoma of infancy, and infantile fibrosarcoma also harbour distinct genetic drivers, including EWSR1::DDIT3, EGFR exon 20 alterations, and ETV6::NTRK3, respectively. This case highlights the diagnostic workup of soft-tissue tumours and underscores the importance of integrating histopathology, IHC, and molecular testing. Identification of PLAG1 rearrangement is crucial for confirming the diagnosis. With the growing number of molecularly defined soft-tissue tumours of diagnostic and prognostic significance, incorporating molecular analysis is essential in the evaluation of soft-tissue lesions.
Multisystem inflammatory syndrome in children (MIS-C) represents a severe postinfectious hyperinflammatory condition following SARS-CoV-2 infection. Despite extensive clinical characterization, histopathologic data-especially from pre-mortem pediatric biopsies-remain scarce. We report a 9-month-old male infant with confirmed SARS-CoV-2 infection and rapid multiorgan failure. Pre-mortem incisional biopsies from the myocardium, lung, and pleura revealed degenerative myocyte changes, endothelial swelling, and fibrin-platelet microthrombi consistent with thrombotic microangiopathy. Immunohistochemistry demonstrated mild CD3+ T-cell-predominant infiltrates and focal SARS-CoV-2 antigen positivity confined to alveolar and bronchiolar epithelium, while myocardial and pleural tissues were negative. These findings highlight early morphologic correlates of immune-mediated vascular injury in MIS-C, characterized by endothelial dysfunction, microvascular inflammation, and T-cell-driven immunopathology in the absence of direct viral cytopathy. This case provides rare pre-mortem evidence of immune-thrombotic endotheliopathy in an infant, bridging clinical and histologic manifestations of pediatric SARS-CoV-2-associated hyperinflammatory disease.
OBJECTIVE:Colorectal cancer (CRC) is the third most common type of cancer worldwide and the fourth most common cause of cancer-related deaths. Innovative approaches like immunotherapy are necessary for treatment-resistant patients with a poor prognosis. This study aimed to investigate the status of CTLA-4, one of the immune checkpoint molecules, in CRCs. MATERIAL AND METHODS:A total of 183 resected CRCs were analyzed retrospectively. Immunohistochemical staining was conducted using an anti-CTLA-4 antibody. The relationship between CTLA-4 and prognostic parameters, such as HER2 and microsatellite instability (MSI), was investigated. RESULTS:One hundred and four of the cases were male, and 79 were female. One hundred fifty-nine of the cases were conventional adenocarcinomas, while 24 were mucinous adenocarcinomas. In 53 of the cases (29%), CTLA-4 showed less than 1% staining in the immune cells, classifying it as negative. In the remaining cases (71%), varying degrees of immune cell staining with CTLA-4 were observed. Conventional adenocarcinomas exhibited a higher expression of CTLA-4 compared to mucinous carcinomas. No statistically significant correlation was found between MSI status and CTLA-4 immune cell staining (p = 0.572). CTLA-4 positivity decreased significantly as tumor diameter decreased (p = 0.029). There was no correlation between the CTLA-4 immunostaining and median survival time. CONCLUSION:CTLA-4 expression was detected in 71% of CRCs. CTLA-4 positivity significantly decreased as tumor diameter decreased. There was no significant association between CTLA-4 expression and MSI or other prognostic parameters. Additionally, no significant correlation was found between CTLA-4 expression and median survival time. Nevertheless, the presence of CTLA-4 expression in the majority of CRCs is promising for anti-CTLA-4 therapy.
OBJECTIVE:Twin pregnancies are accompanied by various perinatal complications. The study of placentae is important for understanding the underlying pathogenesis and pathologies. Annexin A5 (ANXA5) is an anti-thrombotic agent, which is expressed by the placental trophoblasts. Apelin is a novel adipokine with a significant role in angiogenesis of the placenta. The aim of the present study was to compare the gross, histopathological findings and immunohistochemical expression of ANXA5 and apelin of twin placentae with those of matched controls. These findings were also correlated with the clinical features of both mother and neonate. MATERIAL AND METHODS:A prospective, observational study was undertaken for a span of one year. Twin placentae were collected along with their matched controls. The gross and microscopic features, as well as immunohistochemical expression of ANXA5 and apelin in these placentae were noted. RESULTS:There was a significantly lower expression of ANXA5 and apelin in the 24 twin placentae collected when compared with matched controls. The histopathological features of twin placentae included villous infarction (8, 33%), fibrin deposition (24, 100%), chorangiosis (18, 75%), and intraplacental hematoma (18, 75%). CONCLUSION:Both ANXA5 and apelin are vital for placental homeostasis. The reduction in expression of these markers in twin pregnancies indicates their contribution to adverse outcomes of these cases. Studies with larger sample size are required in the future for further exploration of the role of these novel markers.
OBJECTIVE:Non-small cell lung cancer (NSCLC) is a molecularly heterogeneous disease in which both actionable mutations and PD-L1 expression influence therapeutic decisions. This study aimed to evaluate the molecular profile of NSCLC using next-generation sequencing (NGS) and analyse the association of PD-L1 expression with key genetic alterations. MATERIAL AND METHODS:A retrospective analysis was conducted on 87 histopathologically confirmed NSCLC cases. Molecular profiling was performed using the Oncomine™ Lung Focus Assay, which targets major actionable mutations. PD-L1 expression was assessed by immunohistochemistry (IHC) using the Tumour Proportion Score (TPS) and categorised as < 1% (negative), 1- 49% (weak positive), and ≥50% (strong positive). RESULTS:A total of 105 molecular alterations were identified across 87 cases, with EGFR being the most frequently mutated gene (36.2%), followed by KRAS (16.2%) and AR amplification (14.3%). Actionable mutations were defined as alterations with approved targeted therapies or clinical trial eligibility were detected in 59.8% of patients, with EGFR exon 19-21 being the most frequent (25.7%), followed by ALK fusions (5.7%), ERBB2 exon 20 (4.8%), KRAS G12C (3.5%), MET exon 14 skipping (2.9%), and BRAF V600E and ROS1 (1.9% each). PD-L1 expression was observed in 45.7% of cases. PD-L1 positivity was lower in EGFR-mutant tumours compared to EGFR wild-type, suggesting reduced immunogenicity in this subgroup. Conversely, KRAS-mutant tumours exhibited higher PD-L1 expression than KRAS wild-type tumours, suggesting a potential predictive role for immunotherapy. ALK-rearranged tumours showed variable but notable PD-L1 expression. CONCLUSION:The study underscores the importance of integrating NGS-based molecular testing with PD-L1 evaluation for personalised management of NSCLC. Distinct patterns of PD-L1 expression across molecular subtypes, particularly lower in EGFR-mutated tumours and higher in KRAS-mutated tumours, underscore the need for tailored therapeutic strategies and informed sequencing of targeted therapies and immunotherapies.
OBJECTIVE:Medical pathology laboratories have a long-standing tradition while continuously evolving through the integration of traditional and modern diagnostic techniques. Today, rapidly evolving and transforming laboratories require renewal in organizational, infrastructure, and managerial approaches. The aim of this study is to conduct a document-based comparative analysis of physical infrastructure criteria related to pathology laboratories and to examine how convergent and divergent standards are reflected in critical planning decisions. MATERIAL AND METHODS:A document-based comparative analytical design was applied using predefined infrastructure parameters. International guidelines, technical standards, and selected scientific publications, published between January 1, 2000, and April 30, 2025, addressing pathology laboratories or laboratory environments involving chemical and biological risks were included. Infrastructure-related criteria were systematically extracted, classified, and compared across predefined domains to identify areas of convergence, divergence, and indeterminate guidance. RESULTS:Core safety principles-including controlled airflow direction, negative pressure relationships, source-based vapor capture, and contamination-resistant surface materials-demonstrated strong cross-document alignment. In contrast, variability emerged in numeric thresholds and implementation models, particularly for air change rates, lighting parameters, and selected environmental comfort indicators. These variations directly affected planning flexibility, renovation sequencing, and risk-based infrastructure decisions. CONCLUSION:Physical infrastructure planning in pathology laboratories requires contextual interpretation of international standards rather than direct transfer of prescriptive thresholds. A flexible, risk-informed planning approach is essential for sustainable and operationally resilient laboratory environments.
Objective: Due to its effect on polypectomy surveillance, dysplasia grading is essential in colorectal adenomas. We aimed to investigate the terminologies used for high-grade dysplasia in routine practice if any, and to assess the practice patterns of dysplasia grading among Turkish pathologists with reference to current guidelines. Material and Methods: A survey including seven images of colorectal adenomas with low-grade and high-grade dysplasia was sent to pathologists in Türkiye. The images were selected from the Canadian National Polyp Guidelines. The pathologists were asked to grade the dysplasia as in their routine practice. Results: A total of 324 pathologists (including 48 senior residents and 176 gastrointestinal pathologists) participated in the survey. Among staff pathologists, the rate of agreement of dysplasia according to the guidelines was as follows; for colorectal adenomas with low-grade dysplasia, Image 1 (with low-grade cytology)-97.1%, Image 2 (with focal cribriformity)-6.2%, Image 5 (with high-grade cytology)-26.8%, and Image 6 (with slightly high-grade cytology)-48.9%. For colorectal adenomas with high-grade dysplasia, the agreement ratio was >91% (range 91.6-99.6%). However, intramucosal adenocarcinoma was the preferred terminology by 43.8%, 68.5%, and 50% of the participants, respectively. The results were similar for residents. Conclusion: Among pathologists in Türkiye, in contrast to current guidelines for colorectal adenomas, 1. Intramucosal adenocarcinoma is still a commonly used terminology, 2. High-grade cytological features are over-relied upon, 3. Small foci of architectural abnormality are overcalled. Therefore, strategies to increase the usage of established practice guidelines should be developed. A national polyp guideline seems to be necessary for an attempt to standardize the reporting of colorectal adenomas.
Objective: The commonly used embedding medium in frozen section is a commercially available optimal cutting temperature (OCT) compound, which is a water-soluble mixture of glycols and resins. However, its high cost limits its widespread use in laboratories with limited resources. In the present study, we compared two embedding media (OCT compound & Water) based on the mean freezing time and effect on the quality of section in terms of staining and the presence of freezing artifacts in different types of tissues. Material and Methods: Fresh & unfixed specimens from 45 cases were analysed prospectively. The specimens included mucosal margin assessment (n=15), lymph node metastases (n=16), and fatty tissues (breast lumpectomy) for margin assessment (n=14). Average freezing time, presence of freezing artifact (extensive, minimal, or absent) and quality of nuclear and cytoplasmic staining (good, satisfactory, or poor) were noted. Results: Overall mean freezing time was marginally lower for OCT (3`34`) when compared to water. (3`58`) Lymph nodes took the shortest time to freeze irrespective of the embedding medium used. Fatty tissues took the longest time to freeze with water (4`12`) as compared to OCT (3`35`). With OCT, the mean freezing time was lowest for lymph nodes (3`22`) and highest for mucosal margins. (3`45`) Extensive freezing artifacts were more commonly observed with OCT than water. (37.8% vs 31.1% respectively) Staining quality was comparable for both embedding media overall and amongst the different types of tissues. Conclusion: In settings where cost is a limiting factor, water can function as a cheaper and readily available embedding alternative to OCT. In frozen sections involving fatty tissues where time is a limiting factor, OCT provides a shorter mean freezing time and can be used in place of water.
OBJECTIVE:Lung cancer is the most prevalent malignancy among men and women in Türkiye. National guidelines have been established to standardize molecular pathology diagnoses for the detection of driver mutations in non-small cell lung cancer with impact in the management and treatment of the disease. This study examines ROS1 gene alterations comparing immunohistochemistry (IHC) and fluorescence in situ hybridization (FISH) diagnostic techniques in a single-center cohort. MATERIAL AND METHODS:A total of 200 biopsy specimens, including tissue and cytology samples from Ege University Hospital and external consultations (2019-2022), diagnosed with non-small cell lung cancer (NSCLC) were analyzed. ROS1 SP384 IHC staining patterns (H-Score) and reflex molecular testing for EGFR, ALK, and ROS1 were recorded. RESULTS:Among 34 ROS1 IHC-positive cases (16.9%), ROS1 FISH positivity was observed in 7 cases (3.5%), including 5 IHC-positive (5/34; 14.7%) and 2 IHC-negative (2/166; 1.2%). The median H-Score of FISH-positive cases was 60. CONCLUSION:ROS1 IHC exhibited staining in cases harboring ALK, EGFR, and KRAS mutations, including one case with concurrent EGFR and ROS1 alterations. The ROS1 SP384 clone demonstrated 71.43% sensitivity and 84.97% specificity, with a negative predictive value of 99.3%. ROS1 IHC is a valuable screening modality for molecular alterations. FISH validation is recommended, and discordant cases may require NGS or RT-PCR for rare mutations or unidentified fusion partners.
Objective: Giant cell tumor of bone (GCTB) is a rarely metastasizing, locally aggressive tumor. Recurrence and metastasis in GCTB are thought to be driven by the biological behavior of the neoplastic stromal mononuclear cells. Several pathophysiological mechanisms, including expressions of p63, RANK, RANKL, and VEGF, have been proposed to influence this aggressive potential. This study aimed to identify histomorphological and immunohistochemical parameters that may predict recurrence and metastasis in patients with GCTB. Material and Methods: This retrospective study included 32 GCTB patients. Clinical, radiological, and pathological data were reviewed. Histomorphological features, including surgical margins, bone cortex invasion, soft tissue invasion, mitotic count, vascular invasion, percentage of spindle cell areas, and presence of tumor-associated lymphocytes (TALs), along with tumor size and demographic features, were evaluated. Tissue sections were stained with p63, RANK, RANKL, and VEGF. The relationship between these parameters and post-surgical recurrence or metastasis was analyzed. Results: A higher percentage of spindled pattern was significantly associated with a lower frequency of recurrence. A larger tumor diameter at diagnosis was associated with the development of metastasis. Other histomorphological parameters and the expression of p63, RANK, RANKL, and VEGF were not significantly associated with recurrence or metastasis. Conclusion: Percentage of spindled pattern and primary tumor diameter are potential prognostic factors for recurrence and metastasis, respectively, in GCTB.
OBJECTIVE:Synovial sarcoma usually presents with spindle cell morphology with or without epithelial differentiation. Extensive rhabdoid differentiation is a very rare feature with only few cases described in literature. CASE REPORT:We present two cases of synovial sarcoma with rhabdoid differentiation along with their clinical follow-up. Both cases had tumor in the vicinity of joints and showed lung metastasis during follow-up inspite of R0 resection. CONCLUSION:We emphasised that extensive rhabdoid differentiation can be deceptive and challenging for diagnosis in small biopsies and also show an aggressive clinical course with dismal prognosis. Awareness of this rarely described unusual and aggressive histomorphological subtype is prudent due to its distinct diagnostic, prognostic and therapeutic implications.
OBJECTIVE:Despite the legal requirement to complete a thesis during residency training in Türkiye, the extent to which these theses are translated into high-quality scientific publications remains unclear. Disciplinary differences in research culture, resource availability, and clinical workload may influence these outcomes. MATERIAL AND METHODS:This cross-sectional study analyzed 1245 open access residency theses completed between 2018 and 2022 in the fields of pathology (n=344), endocrinology (n=525), and urology (n=376). Theses were retrieved from the National Thesis Center of the Council of Higher Education. Their publication status was identified via searches in PubMed and Google Scholar. Data collected included journal index status (SCI-E, ESCI, ULAKBIM), Journal Impact Factor™ (JIF), citation count, and time to publication. Statistical comparisons were made using chi-squared and Kruskal-Wallis tests with p < 0.05 considered significant. RESULTS:Among the 1245 residency theses analyzed, 344 (27.6%) were in pathology, 525 (42.2%) in endocrinology and metabolic diseases, and 376 (30.2%) in urology. The conversion rate to publication significantly differed across specialties (p = 0.0002): 86 of 344 pathology theses (25.0%), 115 of 525 endocrinology theses (21.9%), and 139 of 376 urology theses (37.0%) were published. Urology theses had the highest representation in SCI-E indexed journals (72.7%), while endocrinology demonstrated the highest mean Journal Impact Factor (2.3; p < 0.0001). The average number of citations per publication was also highest in urology (4.5), although this difference was not statistically significant (p = 0.0673). Median time to publication ranged from 2.3 to 2.7 years, with no significant difference between specialties (p = 0.1287). Differences in the distribution of Q2, Q3, and Q4 journal publications were statistically significant between specialties. CONCLUSION:Endocrinology had the highest number of theses, whereas urology had the highest publication rate and number of citations per publication.
OBJECTIVE:Progesterone receptor (PR) expression is a well-recognized marker in meningiomas, but manual immunohistochemical assessment is subjective and prone to variability. Digital pathology offers objective and reproducible quantification. Despite the availability of FDA-cleared digital PR scoring algorithms in some tumors like those of the breast, their implementation in meningiomas and systematic evaluation of their correlations with clinicopathological features remain scarce. MATERIAL AND METHODS:We retrospectively analyzed 129 meningioma cases resected between 2018 and 2024. Digital PR expression was quantified using the FDA-cleared Ventana uPath PR 1E2 algorithm, originally developed for breast carcinoma. Subsequently, tumors were stratified by age, sex, WHO grade, histological subtype, and localization, while Ki-67 index and mitotic counts were also recorded. Associations with digital PR H-scores were evaluated using non-parametric tests, correlation analysis, and ordinal logistic regression. RESULTS:Digital PR H-scores progressively decreased across WHO grades, with Grade 1 tumors showing the highest values, followed by Grade 2 and Grade 3 (p=0.002). PR expression was inversely correlated with proliferative markers, including Ki-67 index (ρ = -0.42, p < 0.001) and mitotic count (ρ = -0.35, p < 0.01). No significant differences were observed by age or sex. Convexity meningiomas tended to have higher scores than skull base and spinal tumors. CONCLUSION:Digital PR H-score assessment confirmed the inverse association between PR expression and WHO grade, as well as its correlation with proliferative activity. Using an FDA-cleared algorithm originally developed for breast carcinoma, this method provides objective and reproducible evaluation in meningiomas.
Objective: Oncocytic cells are commonly detected on FNA reports but little is known regarding the relationship between the degree of oncocytic cell features and the rate of malignancy (ROM). In this study, we aimed to investigate the importance of oncocytic cells in thyroid FNA with a diagnosis of atypia of undetermined significance (AUS). Additionally, we sought to ascertain if the prevalence of oncocytic cells in FNAs with oncocytic cells is linked to neoplasm and malignancy. Material and Methods: 187 cases belonging to 144 patients diagnosed with AUS in thyroid FNA were re-evaluated for the oncocytic cells, nuclear atypia and microfollicles and then classified as AUS-nuclear with or without oncocytic cells and AUS-other with or without oncocytic cells. The cases that had oncocytic cells were scored according to the proportion of oncocytic cells. Results: ROM was higher in the AUS-nuclear group (28.1%) compared to the AUS-other group (12.2%). AUS-nuclear cases without oncocytic cells had higher ROM compared to the AUS-nuclear cases with oncocytic cells. Rate of neoplasm (RON) was significantly higher in the cases containing 75% or more oncocytic cells than the other cases (p<0.0001). (26.3% for cases with 1-75% oncocytic cells, 81.3% for those with 75% or more oncocytic cells). Conclusion: This study showed that the AUS cases with a dominant oncocytic cell population might be more specific for neoplastic processes. Presence of oncocytic cells in the AUS-nuclear cases causes a decrease in ROM. Emphasizing oncocytic cells in the report may contribute to patient follow-up and treatment in AUS.
Objective: Tartrazine (TZ) is an anionic azo dye widely used to color food products, pharmaceuticals, and cosmetics; however, its harmful effects on the kidneys are still unclear and need to be confirmed. Meanwhile, taurine (TA) is a natural antioxidant amino acid that can provide protection against various forms of glomerulonephritis. Our aim was to study the structural, and biochemical effects of TZ on the kidney and evaluate the potential protection provided by taurine. Material and Methods: We used 28 adult male albino rats equally divided into 4 groups. The control group did not receive TZ or TA. The TA group received 100 mg/kg/day of TA. The TZ group received 100 mg/kg/day of TZ dissolved in distilled water. The TZ/TA group received both TZ and TA. Animal blood samples were obtained to estimate blood urea, creatinine, and random glucose levels. Kidneys samples were examined for structure as well as oxidative enzymes and kidney injury molecule 1 (KIM-1). Results: Compared to the control group, the TZ group showed hyperglycemia, increased markers of oxidative stress, and shrunken, lobulated glomeruli with mesangial expansion, pyknosis, and vacuolation in the tubular lining. There was also strong immunoreactivity for PCNA and caspase-3, a thickened glomerular capillary basement membrane lacking fenestrations, swollen mitochondria with destructed cristae, and increased expression of the KIM-1. In the TZ/TA group, the convoluted tubules mostly retained the normal histological structure, but some tubules still showed a wide lumen and nuclear pyknosis of lining cells. Oxidative markers and random blood glucose levels were significantly reduced. Conclusion: TZ is suggested to cause adverse kidney effects in rats, including kidney injury and structural changes, which can be mitigated by co-administration with TA.
OBJECTIVE:The use of molecular pathology is critical in diagnostics and theranostics. Today, cytological smears are utilized for molecular testing more often than ever. Accurate tumor cell percentage estimation is essential for reliable molecular testing, but its consistency remains uncertain. This study evaluates the reliability of tumor cell percentage estimations among an expert cytopathologist, a molecular cytopathologist, and a molecular pathologist. MATERIAL AND METHODS:Digital images from May-Grünwald-Giemsa (MGG)-stained smear slides of ten EBUS-guided mediastinal lymph node samples were selected. Five regions per slide were evaluated (50 areas from 10 patients). Three pathologists independently estimated tumor cell percentages using predefined categories (0-10%, 11-20%, 21-50%, etc.). Cells were also counted manually as the gold standard. RESULTS:The molecular cytopathologist (Observer 1 -) showed the highest consistency (Kappa = 0.69), followed by the expert cytopathologist (Observer 3 -, Kappa = 0.64), both demonstrating substantial agreement with the gold standard. The molecular pathologist (Observer 2 -) displayed moderate consistency (Kappa = 0.52). Agreement was most significant in the 71-100% category, aligning in over 95% of cases. The lowest value occurred in the 11-20% category. In this category, tumor proportions were frequently overestimated compared to the gold standard. CONCLUSION:Variability in tumor percentage estimations shows the need for standardized protocols and training. Substantial agreement was reached in specific categories. However, discrepancies in borderline cases highlight the importance of accurate assessments. More research is needed to improve estimation methods.
Objective: Preeclampsia is a pregnancy-specific disorder characterized by impaired maternal-fetal immune tolerance. The maternal immune system plays a crucial role in maintaining pregnancy, and its dysfunction is believed to contribute to preeclampsia. Immune checkpoint molecules such as programmed cell death protein 1 (PD-1) and its ligand, programmed death ligand 1 (PD-L1), may play a key role in this process. This study evaluated PD-L1 expression in the placentae of patients with pre-eclampsia (PE) and eclampsia (EC). We also compared PD-L1 expression with histomorphological features and fetal outcomes. Material and Methods: A prospective case-control study was conducted, including fifty pre-eclampsia cases, twenty-five eclampsia cases, and twenty-five normal pregnancy controls. Detailed clinicopathological data, histomorphological features of the placenta, and fetal outcomes were collected. PD-L1 expression was assessed using immunohistochemistry, with a semi-quantitative scoring system. The relationship between PD-L1 expression, histopathological scores, and fetal outcomes was also evaluated. Results: In this study, a lower expression of PD-L1 was observed in pre-eclampsia and eclampsia as compared to a normal pregnancy. Adverse fetal outcomes were associated with lower PD-L1 expression and with reduced placental weight and high histopathological scores (>5). Conclusion: Lower PD-L1 expression was observed in pre-eclampsia and eclampsia compared to normal pregnancies. Reduced PD-L1 expression correlated with histomorphological changes in the placenta and adverse fetal outcomes.
We report a case of young female in her 20s who presented with a supraclavicular soft tissue mass. Diagnostic biopsy showed a malignant round cell tumor with areas of spindling and hyalinized stroma. The utilization of an immunohistochemistry panel revealed positive results for NKX2.2 and CD99 expression. This positivity led to the consideration of a differential diagnosis of Ewing sarcoma, EWSR1::NFATC2- rearranged sarcoma, and mesenchymal chondrosarcoma for further assessment. On further immunohistochemistry with NKX3.1 and EWSR1 break-apart fluorescent in situ hybridization analysis, a diagnosis of mesenchymal chondrosarcoma was rendered which was later on confirmed with biphasic histology on excision specimen. NKX3.1 is a useful immunohistochemistry marker to resolve the differentials when dealing with undifferentiated small round cell sarcoma of bone and soft tissue, especially on a needle biopsy.
Echinococcus granulosus, also known as the dog tapeworm, causes echinococcosis or hydatid disease in humans. It is an anthropozoonotic and non-endemic disease. Hydatid cysts are most commonly found in the liver and lungs, but can occur in any other organ, including the brain, kidneys, bones, and peritoneal cavity. Isolated renal hydatidosis is an extremely rare condition, accounting for only 2-4% of all cases of hydatidosis, with its occurrence in children being even rarer. We are reporting a rare case of isolated renal hydatidosis in a 12-year-old boy.
