Exploring Non-Thermal Plasma and UV Radiation as Biofilm Control Strategies against Foodborne Filamentous Fungal Contaminants.

In recent years, non-thermal plasma (NTP) has emerged as a promising tool for decontamination and disinfection within the food industry. Given the increasing resistance of microbial biofilms to conventional disinfectants and their adverse environmental effects, this method has significant potential for eliminating biofilm formation or mitigating the metabolic activity of grown biofilms. A comparative study was conducted evaluating the efficacy of UV radiation and NTP in eradicating mature biofilms of four common foodborne filamentous fungal contaminants: Alternaria alternata, Aspergillus niger, Fusarium culmorum, and Fusarium graminearum. The findings reveal that while UV radiation exhibits variable efficacy depending on the duration of exposure and fungal species, NTP induces substantial morphological alterations in biofilms, disrupting hyphae, and reducing extracellular polymeric substance production, particularly in A. alternata and F. culmorum. Notably, scanning electron microscopy analysis demonstrates significant disruption of the hyphae in NTP-treated biofilms, indicating its ability to penetrate the biofilm matrix, which is a promising outcome for biofilm eradication strategies. The use of NTP could offer a more environmentally friendly and potentially more effective alternative to traditional disinfection methods.

Undifferentiated Carcinoma with Osteoclast-like Giant Cells of the Pancreas: Molecular Genetic Analysis of 13 Cases.

Undifferentiated carcinoma with osteoclast-like giant cells (UCOGC) of the pancreas is a rare malignancy regarded as a subvariant of pancreatic ductal carcinoma (PDAC) characterized by variable prognosis. UCOGC shows a strikingly similar spectrum of oncogenic DNA mutations to PDAC. In the current work, we analyzed the landscape of somatic mutations in a set of 13 UCOGC cases via next-generation sequencing (NGS). We detected a spectrum of pathogenic or likely pathogenic mutations similar to those observed in PDAC following previously published results (10 KRAS, 9 TP53, 4 CDKN2A, and 1 SMAD4, CIC, GNAS, APC, ATM, NF1, FBXW7, ATR, and FGFR3). Our results support the theory that UCOGC is a variant of PDAC, despite its unique morphology; however, a UCOGC-specific genomic signature as well as predictive markers remain mainly unknown. Programmed death ligand 1 (PD-L1) status remains an important predictive marker based on previous studies.

High tumour mutational burden is associated with strong PD-L1 expression, HPV negativity, and worse survival in penile squamous cell carcinoma: an analysis of 165 cases.

Penile squamous cell carcinoma (pSCC) is a rare tumour with a variable prognosis. More prognostic markers linked to mutational signatures and the tumour immune microenvironment are needed. A cohort made up of 165 invasive pSCC was retrospectively analysed using formalin-fixed, paraffin-embedded tumour tissue, focusing on tumour mutational burden (TMB), programmed death ligand 1 (PD-L1) expression, microsatellite instability (MSI), the number of tumour infiltrating lymphocytes (TILs) expressing cytotoxic T-lymphocyte-associated protein 4 (CTLA4), HPV status determined by p16 immunohistochemistry, and several traditional histopathological variables. High TMB (>10 mut/Mb) was associated with high PD-L1 expression (TPS 50-100%), and HPV-negative status. High PD-L1 expression was linked to HPV negativity, a high number of intratumoural CTLA4+ cells, and brisk lymphocytic infiltrate. High TMB was a significant predictor of shorter overall survival (OS) in both univariate and multivariate analysis when using a median cut-off value of 4.3 mut/Mb, but not when using an arbitrary cut-off of 10 mut/Mb. Low CTLA4+ cell infiltration at the tumour invasion front was a marker of shorter OS and cancer-specific survival in both univariate and multivariate analysis. PD-L1 expression had no significant impact on prognosis. Only two cases were MSI high. The results support the hypothesis of two aetiological pathways in pSCC cancerogenesis: (1) SCC linked to HPV infection characterised by low TMB, less common PD-L1 expression, and a lower number of TILs; and (2) SCC linked to chronic inflammation leading to a high number of acquired mutations (high TMB), HPV negativity, increased neoantigen production (i.e., PD-L1), and high immune cell infiltration.

Localized Insulin-Derived Amyloidosis in Diabetes Mellitus Type 1 Patient: A Case Report.

Localized insulin-derived amyloidosis (LIDA) is a rare local complication of subcutaneous insulin application occurring in patients with diabetes type 1 and 2. A 45-year-old woman with an 11-year history of insulin-dependent diabetes mellitus type 1 underwent a mini-abdominoplasty and excision of a long-standing palpable mass in left hypogastric subcutaneous tissue in the area of long-term insulin application. Histopathological examination revealed insulin amyloidosis as a substrate of the mass lesion. Several months after surgery, there was a transient improvement in previously poor diabetes compensation. In addition to local allergic reactions, abscess formation, scarring, lipoatrophy/dystrophy, and lipohypertrophy, LIDA broadens the differential diagnostic spectrum of local insulin injection complications. LIDA has been described as a cause of poor glycemia compensation, probably due to the conversion of soluble insulin into insoluble amyloid fibrils, which prevents insulin from circulating in the blood and regulating glucose blood concentration. Improvement in diabetes compensation has been described in several reports, including our case. LIDA is a rare local complication of subcutaneous insulin application; accurate diagnosis and treatment have clinical consequences. Immunohistochemical or immunofluorescence distinction from other amyloid types is highly recommended.

Immune cell infiltration, tumour budding, and the p53 expression pattern are important predictors in penile squamous cell carcinoma: a retrospective study of 152 cases.

Penile squamous cell carcinoma (pSCC) is a rare malignancy with a slowly increasing incidence and variable prognosis. Regional lymph node involvement signifies poor prognosis but represents a late sign, and more prognostic markers for effective patient risk stratification are urgently needed. In this retrospective study, 152 tumour samples with formalin-fixed, paraffin-embedded tissue were analysed for traditional pathological variables, tumour budding, p53, p16, and mismatch repair proteins (MMR) immunohistochemistry. The density of tumour lymphocytic infiltrate was also determined, using subjective evaluation by two pathologists (brisk/non-brisk/absent) and also using the immunoscore method, which categorised the cohort into five immunoscore groups according to the number of CD3+ and CD8+ T-cells in both the tumour centre and tumour invasion front. Only one case (0.6%) was MMR-deficient. Tumour budding count ≥5 tumour buds/20× power field and non-brisk/absent lymphocytic infiltrate were significant negative predictors of both the overall survival (OS) and cancer-specific survival (CSS), whereas a low immunoscore was a significant marker of shorter OS but not CSS. Advanced pT stage (3+4) was a significant marker of shorter CSS but not OS. In the multivariate analysis, high-grade budding was a significant parameter if adjusted for the patient's age and associated variables, except for the pN stage. The lymphocytic infiltrate retained its prognostic significance if adjusted for age and associated variables. The negative prognostic significance of the previously described parameters (lymphatic, venous, and perineural invasion, regional lymph node metastasis, and p53 mutated profile) were confirmed in our study. Grade, histological subtype, and HPV status (as determined by p16 immunohistochemistry) showed, surprisingly, little or no prognostic significance.

Loss of SATB2 expression correlates with cytokeratin 7 and PD-L1 tumor cell positivity and aggressiveness in colorectal cancer.

Colorectal carcinoma (CRC) is a disease that causes significant morbidity and mortality worldwide. To improve treatment, new biomarkers are needed to allow better patient risk stratification in terms of prognosis. This study aimed to clarify the prognostic significance of colonic-specific transcription factor special AT-rich sequence-binding protein 2 (SATB2), cytoskeletal protein cytokeratin 7 (CK7), and immune checkpoint molecule programmed death-ligand 1 (PD-L1). We analyzed a cohort of 285 patients with surgically treated CRC for quantitative associations among the three markers and five traditional prognostic indicators (i.e., tumor stage, histological grade, variant morphology, laterality, and mismatch-repair/MMR status). The results showed that loss of SATB2 expression had significant negative prognostic implications relative to overall survival (OS) and cancer-specific survival (CSS), significantly shortened 5 years OS and CSS and 10 years CSS in patients with CRC expressing CK7, and borderline insignificantly shortened OS in patients with PD-L1 + CRC. PD-L1 showed a significant negative impact in cases with strong expression (membranous staining in 50-100% of tumor cells). Loss of SATB2 was associated with CK7 expression, advanced tumor stage, mucinous or signet ring cell morphology, high grade, right-sided localization but was borderline insignificant relative to PD-L1 expression. CK7 expression was associated with high grade and SATB2 loss. Additionally, a separate analysis of 248 neoadjuvant therapy-naïve cases was performed with mostly similar results. The loss of SATB2 and CK7 expression were significant negative predictors in the multivariate analysis adjusted for associated parameters and patient age. In summary, loss of SATB2 expression and gain of CK7 and strong PD-L1 expression characterize an aggressive phenotype of CRC.

Giant cell fibroblastoma: a case report.

Giant cell fibroblastoma is a rare locally aggressive tumor of subcutaneous mesenchymal tissue, occurring mostly on the trunk in young individuals with maximal incidence in the first decade of life. Local recurrences of giant cell fibroblastoma are common if marginally excised, however, distant metastases do not occur. Giant cell fibroblastoma was labelled as a juvenile variant of dermatofibrosarcoma protuberans (DFSP) due to quite frequent combination of both lesions, morphological similarities, identical immunoprofile, and shared gene fusion t(17;22) COL1A1-PDGFB. In this paper, we report a case of a young man with a slowly growing subcutaneous tumor in the groin. The tumor was excised and histological examination identified a mesenchymal tumor with variable cellularity, presence of multinucleated giant cells and pleomorphic spindle cells, which lined pseudovascular or angiectoid spaces. The CD34 immunohistochemistry showed strong positivity in all of these cells, whereas ERG was positive only in endothelial cells in true vessels. These findings led to a suspicion on giant cell fibroblastoma. Because of its borderline malignant behaviour and positive surgical margins, the lesion was subsequently reexcised. The molecular analysis identified the transcription product of gene fusion COL1A1-PDGFB and thus, final diagnosis was confirmed. The article includes review of the literature and brief historical overview of giant cell fibroblastoma concept as an unique entity.

TROP2 Represents a Negative Prognostic Factor in Colorectal Adenocarcinoma and Its Expression Is Associated with Features of Epithelial-Mesenchymal Transition and Invasiveness.

Trophoblastic cell surface antigen 2 (TROP2) is a membrane glycoprotein overexpressed in many solid tumors with a poor prognosis, including intestinal neoplasms. In our study, we show that TROP2 is expressed in preneoplastic lesions, and its expression is maintained in most colorectal cancers (CRC). High TROP2 positivity correlated with lymph node metastases and poor tumor differentiation and was a negative prognostic factor. To investigate the role of TROP2 in intestinal tumors, we analyzed two mouse models with conditional disruption of the adenomatous polyposis coli (Apc) tumor-suppressor gene, human adenocarcinoma samples, patient-derived organoids, and TROP2-deficient tumor cells. We found that Trop2 is produced early after Apc inactivation and its expression is associated with the transcription of genes involved in epithelial-mesenchymal transition, the regulation of migration, invasiveness, and extracellular matrix remodeling. A functionally similar group of genes was also enriched in TROP2-positive cells from human CRC samples. To decipher the driving mechanism of TROP2 expression, we analyzed its promoter. In human cells, this promoter was activated by ß-catenin and additionally by the Yes1-associated transcriptional regulator (YAP). The regulation of TROP2 expression by active YAP was verified by YAP knockdown in CRC cells. Our results suggest a possible link between aberrantly activated Wnt/ß-catenin signaling, YAP, and TROP2 expression.

Penile paraffinoma: a case report.

Penile paraffinoma or sclerosing lipogranuloma is a disease occurring uncommonly in Czechia; a pathologist meets this only rarely. Microscopically, we deal with chronic fibroproductive inflammation localised usually in subcutaneous tissue of the penis. It is caused by previous voluntary injection of liquid paraffin / mineral oil for the purpose of penis circumference augmentation, usually performed by a non-healthcare person or by the patient himself. Human tissues do not have enzymes that can break down synthetic lipids. The application leads, with a variable time lag, to a foreign body giant-cell reaction lasting for years, and often to annoying complications frequently associated with a genital mutilation and sexual dysfunction. The lesion often requires surgical treatment to remove the paraffin substance from the subcutaneous tissue. The surgery does not always lead to satisfying results and the paraffinoma tends to recur. In this article, we describe a case of a man with relapsing paraffinoma, which required excision of subcutis with subsequent plastic surgery with skin graft. During histological examination, lipid droplets were found in dermis and in subcutis, along with xantogranulomatous inflammation. The lipid nature of the material was proven by oil red and Sudan stain. The paper includes clinical and histopathological differential diagnostic consideration, summary of treatment options and relevant literature review.

Development of Radiofrequency Ablation Generator and Balloon-Based Catheter for Microendoluminal Thin-Layer Ablation Therapy Using the Rat Duodenum as a Model of Low-Impedance Tissue.

Radiofrequency ablation (RFA) is a routinely used, safe, and effective method for the tissue destruction. Often, in case of its application in malignant conditions, the extent of tissue destruction is insufficient due to the size of the target lesion, as well as due to the risk of heat-induced damage to the surrounding organs. Nevertheless, there are conditions requiring superficial precise-depth ablation with preservation of deeper layers. These are represented, for example, by mucosal resurfacing in case of Barrett's esophagus or treatment of recurrent mucosal bleeding in case of chronic radiation proctitis. Recently, new indications for intraluminal RFA use emerged, especially in the pancreatobiliary tract. In the case of intraductal use of RFA (e.g., biliary and pancreatic tract), there are currently available rigid and needle tip catheters. An expandable balloon-based RFA catheter suitable for use in such small-diameter tubular organs could be of benefit due to possible increase of contact between the probe and the target tissue; however, to prevent excessive tissue damage, a compatible generator suitable for low-impedance catheter/tissue is essential. This project aimed to develop a radiofrequency ablation generator and bipolar balloon-based catheter optimized for the application in the conditions of low-impedance tissue and (micro)endoluminal environment. Subsequent evaluation of biological effect in vivo was performed using duodenal mucosa in Wistar rat representing conditions of endoluminal radiofrequency ablation of low-impedance tissue. Experiments confirming the safety and feasibility of RFA with our prototype devices were conducted.

Giant cell myocarditis in young woman diagnosed at the autopsy: a case report.

Giant cell myocarditis (GCM) is a rare inflammatory disease of the heart that often affects younger patients. The clinical course is typically rapid with fulminant congestive heart failure. Prognosis is poor; the proper diagnosis is often rendered at the autopsy. Herein, we present a prototypical case of this rare type of myocarditis, affecting a 44-year-old previously healthy woman who was referred to the intensive care department due to an acute onset cardiac arrest followed by resuscitation. The heart ultrasound and imaging examinations revealed a severe dysfunction and dilatation of both ventricles, without any significant finding in the coronary arteries. Twelve days after the initial presentation, the patient died due to congestive heart failure refractory to intensive therapy. The post-mortem histology of the heart revealed multiple small necrotic foci in the myocardium in both ventricles, with dense inflammatory infiltration with abundant multinucleated giant histiocytes, in line with a diagnosis of GCM. The natural history, pathophysiology, and histological differential diagnosis is discussed, together with review of the relevant literature including uncommon and emerging units.

Cytokeratin 7 expression as a predictor of an unfavorable prognosis in colorectal carcinoma.

Colorectal carcinoma (CRC) is associated with significant morbidity and mortality worldwide. Cytokeratins (CKs) are widely expressed in various types of carcinomas, whereas in CRC it is usually CK7 - and CK20 + . A subset of CRCs is CK7 + . This study aims to determine the prevalence of CK7 expression in CRC and its impact on overall survival. We analyzed 300 randomly selected surgically treated CRC cases using paraffin embedded tumor tissue samples and evaluated CK7 and CK20 expression using the tissue microarray method. Tumors with positivity > 10% and > 25% of tumor cells were considered CK7 and CK20 positive, respectively. Expression of both CKs and several clinical-pathological variables (stage, grade, laterality, mismatch-repair/MMR status) were evaluated using patient follow up data (Kaplan-Meier analysis of cancer-specific survival (CSS)). Significant results include shorter CSS (restricted mean 4.98 vs. 7.74 years, P = 0.007) and 5-year survival (29.4% vs. 64.6%, P = 0.0221) in CK7 + tumors compared to CK7 - tumors, respectively; without significant association with grade, stage or right-sided location. These results were significant in a multivariate analysis. CK20 + tumors are more frequently MMR-proficient and left-sided. MMR-deficient tumors are more frequently right-sided and had longer survival. CK7 expression, right-sided location (rmean CSS 6.83 vs. 8.0 years, P = 0.043), MMR-proficiency (rmean CSS 7.41 vs. 9.32 years, P = 0.012), and UICC stages III + IV (rmean CSS 6.03 vs. 8.92 years, P < 0.001) of the tumor correlated with negative prognostic outcomes, whereas the most significant results concern stage and CK7 positivity. The result concerning negative prognostic role of CK7 differs from those obtained by several previous studies focused on this topic.

Heat Shock Proteins 27, 70, and 110: Expression and Prognostic Significance in Colorectal Cancer.

Heat shock proteins (HSPs) are evolutionarily conserved chaperones occurring in virtually all living organisms playing a key role in the maintenance of cellular homeostasis. They are constitutively expressed to prevent and repair protein damage following various physiological and environmental stressors. HSPs are overexpressed in various types of cancers to provide cytoprotective function, and they have been described to influence prognosis and response to therapy. Moreover, they have been used as a tumor marker in blood serum biochemistry and they represent a potentially promising therapeutic target. To clarify prognostic significance of two canonical HSPs (27 and 70) and less known HSP110 (previously known as HSP105) in colorectal carcinoma (CRC), we retrospectively performed HSP immunohistochemistry on tissue microarrays from formalin-fixed paraffin-embedded tumor tissue from 297 patients with known follow-up. Survival analysis (univariate Kaplan-Meier analysis with the log-rank test and multivariate Cox regression) revealed significantly shorter overall survival (OS, mean 5.54 vs. 7.07, p = 0.033) and borderline insignificantly shorter cancer specific survival (CSS, mean 6.3 vs. 7.87 years, p = 0.066) in patients with HSP70+ tumors. In the case of HSP27+ tumors, there was an insignificantly shorter OS (mean 6.36 vs. 7.13 years, p = 0.2) and CSS (mean 7.17 vs. 7.95 years, p = 0.2). HSP110 showed no significant impact on survival. Using Pearson's chi-squared test, there was a significant association of HSP27 and HSP70 expression with advanced cancer stage. HSP27+ tumors were more frequently mismatch-repair proficient and vice versa (p = 0.014), and they occurred more often in female patients and vice versa (p = 0.015). There was an enrichment of left sided tumors with HSP110+ compared to the right sided (p = 0.022). In multivariate Cox regression adjusted on the UICC stage, grade and right/left side; both HSPs 27 and 70 were not independent survival predictors (p = 0.616 & p = 0.586). In multivariate analysis, only advanced UICC stage (p = 0) and right sided localization (p = 0.04) were independent predictors of worse CSS. In conclusion, from all three HSPs examined in our study, only HSP70 expression worsened CRC prognosis, although stage-dependent. The contribution of this article may be seen as a large survival analysis of HSPs 27 and 70 and the largest analysis of HSP110 described in CRC.

FOXF1 as an Immunohistochemical Marker of Hilar Cholangiocarcinoma or Metastatic Pancreatic Ductal Adenocarcinoma. Single Institution Experience.

Cholangiocarcinoma (CCA) is a liver malignancy associated with a poor prognosis. Its main subtypes are peripheral/intrahepatic and hilar/extrahepatic CCA. Several molecular, morphological and clinical similarities between hilar/extrahepatic CCA and pancreatic ductal adenocarcinoma (PDAC) have been described. FOXF1 is a transcription factor which has been described to have prognostic significance in various tumors and it is involved in the development of bile ducts. The aim of this study is to determine occurrence of nuclear expression of FOXF1 in both subtypes of CCA and metastatic PDAC and assess its potential usefulness as a diagnostic marker. Secondary aims were to investigate the use of C-reactive protein (CRP) immunohistochemistry for diagnosing intrahepatic peripheral CCA and the significance of histological features in CCA subtypes. 32 archive specimens of CCA, combined hepatocellular carcinoma-CCA (HCC-CCA) and liver metastasis of PDAC were stained by FOXF1 and CRP immunohistochemistry and evaluated to determine histological pattern. The CCAs were classified radiologically into peripheral/intrahepatic and hilar subtype. Using Fisher exact test, we identified nuclear FOXF1 as a fairly specific (87%) but insensitive (65%) marker of hilar and extrahepatic CCA and metastatic PDAC (p = 0.005). CRP immunohistochemistry was characterized by a high sensitivity and specificity, of 79% and 88%, respectively (p = 0.001). We did not identify any histomorphological features associated with either types of CCA or metastatic PDAC. As a conclusion of novel finding, FOXF1 immunohistochemistry may be regarded as a specific but insensitive marker of hilar/extrahepatic CCA and metastatic PDAC and it may help distinguish them from peripheral CCA.

Small bowel perforation and death caused by anaplastic thyroid carcinoma metastasis in a patient with concomitant colonic and bilateral breast carcinoma.

Undifferentiated or anaplastic thyroid carcinoma (ATC) is rare and one of the most aggressive human malignancies. The tumor is usually voluminous and fast-growing and mostly affects older women. The most common sites of distant metastases are the lungs, brain, and bones. Herein, we describe the case of a 66-year-old woman with a history of bilateral breast carcinoma and ATC, who presented with an acute abdomen and subsequently died. At autopsy, an isolated metastasis of ATC in the small intestine leading to bowel perforation was found. Moreover, there was adenocarcinoma in the descending colon. The review of extra-abdominal malignancies metastasizing to bowel and coincidence of breast and thyroid carcinoma is included.

Obstructive Jaundice Secondary to Pancreatic Head Metastasis of Malignant Amelanotic Melanoma as the First Clinical Manifestation.

Malignant melanoma is commonly known for its high probability of metastasizing to distant organs. Metastases to gastrointestinal tract are well documented, but resulting jaundice is only scarcely seen. We present a case of histologically verified metastasis of amelanotic melanoma to the head of pancreas infiltrating the common bile duct and consequently causing obstructive jaundice which constituted its first clinical manifestation. Multidisciplinary approach is essential in patients with malignant melanoma since early detection of the melanoma or its metastases may improve patients' clinical outcome, especially owing to the use of targeted biological treatment without any delay.

Secretory carcinoma of salivary type in a lymph node presenting as a neck cyst diagnosed by cytology: A case report.

Secretory carcinoma (SC) is a relatively recently described salivary gland adenocarcinoma characterized by ETV6-NTRK3 gene fusion and, in most cases, indolent clinical behavior. Morphologically, the tumor shows a glandular architecture and the presence of monophasic tumor cells with vacuolated cytoplasm, low-grade nuclear atypia, and mucin production, with possibly a tubular, papillary, or cystic arrangement. In this article, we describe a case of a 52-year old man with SC involving a neck lymph node clinically manifesting as a slowly growing cystic neck mass without recent proof of the primary tumor, but with a history of a parotid gland "cystadenopapilloma," which had been removed 35 years prior. A fine-needle aspiration biopsy revealed a diagnosis of SC. Subsequent histopathological examination after lymph node dissection confirmed the diagnosis. The tumor showed typical features of SC, including immunohistochemical positivity for NTRK and NTRK3 gene rearrangement, detected using in situ hybridization. We discuss that the tumor may be a late metastasis occurring 35 years after resection of undiagnosed salivary SC or a primary SC arising from heterotopic salivary tissue within a lymph node. Differential diagnostic considerations and review of relevant literature are included.

Small bowel perforation and death caused by anaplastic thyroid carcinoma metastasis in a patient with concomitant colonic and bilateral breast carcinoma

Undifferentiated or anaplastic thyroid carcinoma (ATC) is rare and one of the most aggressive human malignancies. The tumor is usually voluminous and fast-growing and mostly affects older women. The most common sites of distant metastases are the lungs, brain, and bones. Herein, we describe the case of a 66-year-old woman with a history of bilateral breast carcinoma and ATC, who presented with an acute abdomen and subsequently died. At autopsy, an isolated metastasis of ATC in the small intestine leading to bowel perforation was found. Moreover, there was adenocarcinoma in the descending colon. The review of extra-abdominal malignancies metastasizing to bowel and coincidence of breast and thyroid carcinoma is included.

Lymph node metastasis of parotid gland high-grade adenoid-cystic carcinoma.

Adenoid cystic carcinoma (ACC) is one of the most common salivary gland malignancies. In rare cases, ACC undergoes high-grade transformation, which is associated with poor prognosis, in contrast to relatively long survival in the conventional ACC. Conventional ACC is characterized by typical histopathology showing glandular arrangement with sharply demarcated lumina, the tumor cells have sparse cytoplasm and angulated hyperchromatic nuclei. ACCs undergoing high-grade transformation lack these morphological features. In this paper we present a case of 46 years old female patient presenting with locally advanced tumor of the parotid gland and neck lymphadenopathy, coming for surgery. A suspect lymph node was sent to freeze section histology. Large non-cohesive cells with vesicular nuclei and prominent nucleoli along with well persevered lymph node architecture were seen in the frozen slide. This finding lead to suspicion of a lymphoma, the surgery finished in the extent of superficial parotidectomy and selective neck dissection of regions II-IV. Subsequent histopathological examination of formalin-fixed lymph node proofed epithelial nature of the atypical cells by p63 positivity. In the parotid gland resection specimen, an ACC with high-grade component was indentified. The high-grade ACC shared cell morphology with the lymph node metastasis. 17 from 20 lymph neck nodes contained metastases of high-grade ACC. Interestingly, there was strong CD117 expression in the high-grade ACC, whereas the conventional part was fully negative. To the best of our knowledge, the high-grade ACC of the parotid gland was reported only in 10 cases in the medical literature.

Dermatofibrosarcoma protuberans with fibrosarcomatous transformation: a case report.

Dermatofibrosarcoma protuberans is a quite rare local aggressive tumor of dermis and subcutis, revealing characteristic morphology and chromosomal translocation (17; 22)(q21;q13) with gene fusion COL1A1-PDGFB. The tumour almost never metastasizes and complete excision signs an excellent prognosis. Approximately in 10% of cases, dermatofibrosarcoma undergoes a fibrosarcomatous transformation associated with metastatic disease and worse prognosis. In this paper, we refer a case of a male patient with subcutaneous tumor in back region, in which the small biopsy lead to diagnosis of a spindle cell sarcoma. However, only the histopathological examination of the entire tumor in the material from the radical surgery detected the dermatofibrosarcoma protuberans with fibrosarcomatous transformation. Both components of the tumor showed the characteristic genetic alteration. Identification of fibrosarcomatous component within the DFSP matters in prognosis. Distinction between fibrosarcoma arising within the dermatofibrosarcoma protuberans and fibrosarcoma arising de novo is of therapeutic consequence: the patients with metastatic or inoperable DFSP with fibrosarcomatous transformation may profit form imatinib treatment.