Recurrent Adamantinoma With Fibrous Dysplasia-like Feature.

Adamantinoma (AD) is a rare, slow-growing primary malignant bone tumor characterized by a biphasic morphology of clusters of epithelial cells and spindle cell osteofibrous components. A strong relationship between AD and osteofibrous dysplasia (OFD) has been proposed, while fibrous dysplasia (FD) has been rarely associated with AD. We present an AD case that was followed and histologically evaluated 3 times over 6 years with different morphological patterns. The tumor in the primary biopsy and after complete resection showed classical features of AD and osteofibrous-like pattern, while the recurrent lesion presented with exclusively spindle cell morphology and was thus diagnosed as FD. However, the extensive immunohistochemical analysis in all 3 lesions revealed strong reactivity for pancytokeratin, vimentin, p63, and podoplanin, which are characteristic for AD. Although, in the FD-like section of the tumor from the first recurrence the positivity of podoplanin was stronger than pancitokeratin, which was variably positive on spindle cells. The present case highlights the problem of diagnosing AD based on a single biopsy with one tumor's component predominating over the other, and at the same time emphasizes the importance of using immunohistochemical staining for keratin and podoplanin when the histopathological features of (osteo)fibrous lesion can be linked to AD.

The prognostic significance of Nectin-2 and Nectin-4 expression in glial tumors.

Glial tumors are the most frequent neoplasms of the central nervous system in adults and despite recent advances in diagnosis and treatment of the disease, the prognosis of glioma is poor. Therefore, there is a great need to identify new prognostic factors and potential immunotherapeutic targets. Members of the Nectin family of proteins are gaining significant attention as possible diagnostic and immunotherapeutic targets in many solid tumors, but they have not been extensively investigated in glial tumors. The aim of the present study was to evaluate the expression of Nectin-2 and Nectin-4 in glial tumors of different grades, and to assess their prognostic value. The results showed heterogeneous expression of Nectin-2 and Nectin-4 in tumor cells and neuropil, with significantly higher Nectin-2 expression compared to Nectin-4, but without differences among tumor grades. In addition, the expression of Nectin-2 and Nectin-4 was associated with shorter survival times in patients with grade II/III gliomas. These results suggest that Nectin-2 and Nectin-4 expression may be used as an independent prognostic indicator for patients with II/III gliomas. This study contributes to the development of personalized care for patients with glioma and provides a basis for further research on nectin-based immunotherapy for brain tumors.

Primary Nodal Unclassifiable CD20 Negative Diffuse Large B-cell Lymphoma With Dual IgK and TCR Gene Rearrangement: A Diagnostic Challenge.

Non-Hodgkin lymphomas are most frequently classified based on the lineage marker expression. However, lymphomas with aberrant marker expression as well as monoclonal IgH/IgΚ and TCR gene rearrangements may co-exist which can be misleading and confusing. Primary CD20 negative diffuse large B-cell lymphomas (DLBCL) represent a rare entity, and they account for 1% to 3% of cases. However, some CD20 negative DLBCLs could not be classified into known variants, creating both diagnostic and therapeutic dilemma's. Primary CD20 negative DLBCL are more likely to have a non-germinal centre subtype, a higher proliferation index, more frequent extra-nodal involvement, a poorer response, and poorer prognosis to conventional treatment compared to CD20 positive DLBCL. A 66- year-old postmenopausal lady, presented with palpable, bilateral neck lymphadenopathy and difficulty swallowing. She also had left leg lymphoedema, poor appetited, fatigue and weight loss. Her symptoms lasted approximately 1 month. After histological, immunohistochemical and clonality analysis of the lymph node the patient was diagnosed with primary nodal CD20 and PAX-5 negative DLBCL with dual immunoglobulin light-chain kappa (IgK) and T-cell receptor (TCR) gene rearrangement. This unusual and unique case presented a diagnostic challenge because it was CD20 and PAX-5 negative, had dual IgK and TCR gene rearrangement and, it could not be classified within the known and well established CD20 negative DLBCL variants. Describing such cases emphasises the fact that lymphomas unclassifiable within known variants of CD20 negative DLBCL do exist and that range and heterogeneity of CD20 negative DLBCL continues to evolve, and pathologist should be aware of these uncommon, atypical mature B-cell neoplasms.

Dedifferentiated Leiomyosarcoma of the Auricle with Heterologous Osteosarcoma Component: Case Report and Literature Review.

Leiomyosarcomas are rare malignant tumors of smooth muscles. Head and neck involvement by this disease is very rare, and cutaneous leiomoysarcomas of the ear are even rarer. This is way clinically they are usually mistaken for either squamous or basal cell carcinomas, as was the case in an 85-year-old male patient presented in this report. However, the final diagnosis was even more interesting considering that it was a dedifferentiated leiomyosarcoma of the auricle with a heterologous component of osteosarcoma. The auricular cutaneous malignancies have a much higher rate of recurrence than the corresponding malignancy in other regions of the head and neck, even when resected with negative surgical margins, and dedifferentiated leiomyosarcoma is clinically even more aggressive. Thus, the treatment of choice is a total auriculectomy and great attention should be paid to appropriate margins.

Fatal Outcome of Emphysematous Gastritis due to Sarcina ventriculi Infection.

Sarcina ventriculi is an increasingly common bacterium with a variable pathogenic role. It is often an incidental finding in asymptomatic patients but can also lead to life-threatening conditions, such as gastric perforation and emphysematous gastritis. We report a case of a 14-year-old boy with fatal emphysematous gastritis caused by S. ventriculi, who presented with abdominal pain and vomiting. His medical history included infantile left hemiparesis and operation of patent ductus arteriosus. Emergency surgery was scheduled due to the extremely dilated stomach and gastric pneumatosis, and a total gastrectomy was performed. On the third postoperative day, he suddenly dies, and the diagnosis was confirmed postmortem. This case is an opportunity to review the clinical presentation of emphysematous gastritis and to point out the role of the histopathological examination for the identification of the bacteria.

The diagnostic challenge of adenocarcinoma in pulmonary nodular lymphoid hyperplasia.

Pulmonary nodular lymphoid hyperplasia is a rare, nonneoplastic lymphoproliferative disorder mostly manifesting as one or more nodules or localized lung infiltrates. The lesion comprises reactive germinal centers with well-preserved mantle zones and sheets of interfollicular mature plasma cells, lymphocytes, histiocytes, and neutrophils. The radiological finding is not specific, and the diagnosis of pulmonary nodular lymphoid hyperplasia relies generally on pathohistological and immunohistochemical analyses. The most important differential diagnoses are extranodal marginal zone lymphoma of mucosa-associated lymphoid tissue and immunoglobulin G4-related sclerosing disease. Nonetheless, we present a case of pulmonary nodular lymphoid hyperplasia in a 69-year-old woman with the diagnostic challenge of cytological atypia in alveolar spaces inside the lymphoid tissue, coexisting with the diagnosis of adenocarcinoma of the lepidic pattern. Therefore, this case highlights the importance of identifying these rare benign and reactive lymphoproliferative diseases given the risk of developing not only lymphoma but also carcinoma.

Undifferentiated pleomorphic sarcoma in oropharyngeal mucosa of patients with multiple basal cell carcinomas.

Malignant mesenchymal tumors of oropharyngeal mucosa are rare. Those with fibroblastic and histiocytic differentiation in the skin are called atypical fibroxanthoma (AFX) and in the soft tissue undifferentiated pleomorphic sarcoma (UPS). Here we present a case of an older patient with a history of multiple basal cell carcinomas and recently with a rapidly growing polypoid lesion in the mucosa of posterior oropharyngeal wall with AFX/UPS morphology. The differential diagnosis, histological pitfalls of this poorly characterized mesenchymal lesions, and the challenges associated with treatment are discussed.

Expression profiles of metallothionein-I/II and megalin/LRP-2 in uterine cervical squamous lesions.

Metallothioneins (MTs) are phylogenetically old cysteine-rich proteins, which are implicated in a variety of physiological and pathological processes. Their growth-regulating, anti-apoptotic and anti-inflammatory functions have been attributed not only to intracellular free radical scavenging and to zinc and copper regulation but also to the ability of secreted MT to bind on surface lipoprotein receptor-megalin/LRP2, which enables the endocytosis of MT-I/II and a wide range of other functionally distinct ligands. In the present study, we analysed the expression pattern of both proteins in 55 cases of premalignant transformation of cervical squamous cells, i.e. in low- and high-grade squamous intraepithelial lesion (LSIL and HSIL). The data showed that in LSIL (cervical intraepithelial neoplasia CIN1; N = 25) MTs were present only in basal and parabasal cells and that megalin was only weakly expressed. In HSIL (CIN2; N = 15 and CIN 3/carcinoma in situ; N = 15), however, overexpression and co-localization of MT with megalin were found in the entire hyperplastic epithelium. Moreover, megalin immunoreactivity appeared on the glandular epithelium and vascular endothelium, as well as on lymphatic cells in stroma. Besides, multiple megalin-positive cells expressed phosphorylated Akt1, implying that MT- and/or megalin-dependent prosurvival signal transduction pathways might contribute to the development of severe cervical dysplasia. The data emphasize the diagnostic power of combined MT/megalin analysis in pre-cancer screening.

Diagnostic challenge of soft tissue extranodal Hodgkin lymphoma in core-needle biopsy: case report.

Hodgkin lymphoma (HL) is an uncommon malignancy usually limited to the lymph nodes and lymphatic system while extranodal involvement is much less common than in non-Hodgkin lymphoma. The current report presents an unusual case of primary classical HL (cHL), nodular sclerosis type with mixed cellularity in buttock soft tissue of 78-year old man. Primary lymphoma of the gluteal muscle is a rare disease and primary cHL is even rarer. In addition, to this unusual extranodal presentation, the present case highlight a diagnostic challenge in fine-needle biopsy masquerading a low grade sarcoma, primarily myxoinflammatory fibrosarcoma or an inflammatory lesion. However, surgical biopsy and immunohistochemistry guided correct diagnosis that was of major interest for further successful treatment.

Bone Marrow Burkitt Lymphoma in a Child.

Burkitt lymphoma (BL) is a highly aggressive but potentially curable disease as long as adequately treated within due time. BL may occur primarily and exclusively in the bone marrow as a form of peripheral and extranodal disease. BL cases with isolated bone marrow involvement are challenging in regard to a prompt diagnostic process. We report a case of a sporadic extranodal subtype of isolated bone marrow BL in an 11-year-old boy. Bone marrow aspiration and biopsy, flow cytometry, and immunohistochemistry along with cytogenetics are compulsory in order to achieve the adequate diagnosis.

The Immunohistochemical Pattern of Epithelial-Mesenchymal Transition Markers In Endometrial Carcinoma.

The majority of endometrial carcinoma are diagnosed at an early stage and exhibit a favorable prognosis. However, 10% to 15% of ECs recur and the majority are type II tumors which are high-grade carcinomas. The epithelial-mesenchymal transition (EMT) has been considered as a fundamental step for the development of the invasive phenotype of cancer cells. During EMT, many of epithelial surface markers, primarily E-cadherin disappear, and mesenchymal markers including N-cadherin gain. This feature resides predominantly at the invasive front (IF) of the tumor. Therefore, we examined the immunohistochemical expression of E-cadherin and N-cadherin at the IF, in central areas of the tumor and lymphovascular space, in type I and type II endometrial carcinoma. The association of each protein with the clinicopathologic features was also evaluated. Our results confirmed a stronger E-cadherin immunostaining in type I tumors indicating that the loss of E-cadherin may be responsible for a more aggressive behavior of type II ECs. In both types, E-cadherin was strongly expressed in central areas and the reactivity decreased toward the IF. On contrary, N-cadherin was overexpressed at the IF confirming an inverse relationship between these markers. In addition, a decrease in E-cadherin expression was observed in cells within the lymphovascular space. Downregulation of E-cadherin was associated only with high-grade tumors while no correlations between both markers and other clinicopathologic features were found. Our results confirm that EMT occurs at the IF that represents a critical interface between the tumor and the host.

Malignant Perivascular Epitheloid Cell Tumor with an Unusual Immunophenotype in a Ten-Year-Old Child.

Introduction: Perivascular epitheloid cell tumors (PEComa) represent a group of usually benign mesenchymal neoplasms. Malignant variants are usually found only in adults.Case: We present a 10-year-old girl with infraclavicular malignant PEComa, negative for HMB-45 and Melan A but focally positive for MITF.Conclusion: To the best of our knowledge, no malignant variant of PEComa has been described in soft tissue in a child. Generally, PEComas are immunoreactive for HMB-45 and/or Melan A while our case was negative for both. Further studies are necessary to elucidate the significance of this immunohistochemical finding.

Recurrent amelanotic melanoma of nasal cavity: Biological variability and unpredictable behavior of mucosal melanoma. A case report.

The aim of this report is to present a case of a patient with a recurrent nasal cavity amelanotic melanoma (AM), with emphasis on diagnosis and therapy options of this clinical entity. A 65-year-old female patient presented with pain in the right cheek region and nasal obstruction. In 2013, she was diagnosed with mucosal melanoma (MM) of the left nasal cavity. After endoscopic surgery and radiotherapy, the patient was followed by the oncology team. Five years after the initial diagnosis, rhinoscopy showed a tumorous formation in the right nasal cavity. The tumor mass was without black discoloration and was the same color as the surrounding nasal mucosa. Microscopic examination after biopsy of the tumor confirmed amelanotic MM. The patient underwent an additional endoscopic surgery. A complete standard diagnostic workup for MM found metastases in head and neck lymph nodes, on both sides. MMs of head and neck are uncommon malignancies. Unique biology of MM cells causes a high rate of recurrences. This report presents an example of recurrent AM of the nasal cavity, in treatment with checkpoint inhibitor (pembrolizumab), which could provide a good therapy option for patients with MM.

Inter-laboratory comparison of Ki-67 proliferating index detected by visual assessment and automated digital image analysis.

BACKGROUND: Proliferation rate is a major determinant of the biologic behavior of the tumor and provides information that can be used to guide treatment decisions. METHODS: This ring study included 27 pathologists from 14 Institutions, in order to assess inter-observer concordance between pathologists in Croatia. We analyzed Ki-67 proliferative index on ten randomly selected breast cancer samples comparing consistency between visual assessment using light microscopy compared to digital image analyses results from one central laboratory as a referral value. RESULTS: When we analyzed Ki-67 as numeric value high concordance rate was found between Ki-67 score visually assessed in all participating Institutions compared to referral value assessed by digital image analysis (ICC 0.76, 95% CI 0.58-0.91), and Krippendorff's alpha was 0.79 (95% CI 0.58-1.00). Concordance was better in slides with higher Ki-67 values. When we categorized Ki-67 values according to generally accepted 20% cut-off value we noticed the lower concordance rate among participants in our study. CONCLUSION: Proliferation remains one of the most important parameters for tumor characterization helpful in making clinical decisions, but it should be used with great caution. Standardization of the Ki-67 assessment is essential and proliferating index should be expressed as exact numeric value. For patients with proliferative index near the cut-off value, other factors must be considered in making clinical decisions.

Antiphospholipid antibodies associated with nodal marginal zone lymphoma and its progression to diffuse large B-cell lymphoma-A case report.

An association between autoimmune events, as well as the development of antiphospholipid (aPL) antibodies and lymphoproliferative disorders is well recognized. We present the patient with coagulation abnormalities and non-Hodgkin lymphoma (NHL), primarily diagnosed as nodal marginal zone B-cell lymphoma (NMZL), and in relapse as diffuse large B-cell lymphoma (DLBCL). In the follow-up period, the patient simultaneously developed different aPL antibodies. The presence of aPL antibodies in NHL is frequent but it is not common in the NMZL. The aim of the present case report is to highlight the possible underlying increase of aPL antibodies in NMZL patients with coagulation tests abnormalities.

Acid ceramidase inhibition sensitizes human colon cancer cells to oxaliplatin through downregulation of transglutaminase 2 and ß1 integrin/FAK-mediated signalling.

Acid ceramidase (ASAH1) has been implicated in the progression and chemoresistance in different cancers. Its role in colon cancer biology and response to standard chemotherapy has been poorly addressed so far. Here, we have investigated ASAH1 expression at the protein level in human colon cancer cell lines and tissues from colon cancer patients, and have examined in vitro the possible link between ASAH1 expression and functional activity of p53 protein whose inactivation is associated with the progression from adenoma to malignant tumour in colon cancer. Finally, we have explored the role of ASAH1 in response and resistance mechanisms to oxaliplatin (OXA) in HCT 116 colon cancer cells. We have demonstrated that human colon cancer cells and colorectal adenocarcinoma tissues constitutively express ASAH1, and that its expression is higher in tumour tissues than in normal colonic mucosa. Furthermore, we found an inverse correlation between ASAH1 expression and p53 functional activity. Obtained data revealed that ASAH1 was involved in HCT 116 cell response to OXA and that anti-proliferative, pro-apoptotic, anti-migratory and anti-clonogenic effects of OXA could be significantly increased by combination treatment with ASAH1 inhibitor carmofur. Increased OXA sensitivity was associated with downregulation of signalling involved in acquired resistance to OXA in colon cancer, in particular transglutaminase 2 and ß1 integrin/FAK, which resulted in the suppression of NF-κB and Akt. Thus, combination of OXA with ASAH1 inhibitors could be a promising strategy to counter chemoresistance and improve treatment outcome in advanced colon cancer.

Unusual presentation of plasmablastic lymphoma involving ovarian mature cystic teratoma: a case report.

BACKGROUND: Plasmablastic lymphoma (PBL) is relatively new clinical entity described as a distinct subtype of diffuse large B-cell lymphoma (DLBCL). It is characterized by its aggressive nature and proliferation of large neoplastic cells resembling immunoblasts including cells with more obvious plasmacytic differentiation. In this case report, we describe an unexpected finding of PBL associated with a mature cystic teratoma of the ovary in a young immune competent woman. CASE PRESENTATION: A 19-year old woman was admitted to the hospital with generalized lymphadenopathy, a pelvic tumor mass measuring 35 × 30 cm and a 4 cm lump in her right breast. She underwent a right salpingo-oophorectomy, lymphadenectomy, splenectomy, omentectomy, and a right breast lumpectomy. On macroscopic examination the right ovary was replaced by a thick-walled multilocular cystic tumor. Upon incision, the cysts were filled with thick, greasy sebaceous material and hair and there were several solid nodules within the cyst walls. Histological examination revealed a mature cystic teratoma and malignant non-Hodgkin lymphoma (NHL) within the solid nodules. Tumor tissue from the right breast, spleen and lymph nodes, all had the same histological, NHL morphology. After extensive immunostaining, a diagnosis of PBL was made. Following surgery, the patient was treated with different chemotherapy regimens, without any significant regression of the disease, and died of multiple organ failure. CONCLUSIONS: Primary NHL of the ovary is relatively rare occurrence while secondary involvement by lymphoma is much more common. PBL is a rare lymphoma, primarily reported in the jaw and oral mucosa, but also documented in extra-oral sites. To the best of our knowledge, this is the first case described in a mature ovarian cystic teratoma. Although the patient was HIV-negative and immune competent, she had progressive disease and died despite aggressive chemotherapy 11 months after the initial diagnosis.

Predictive Value of Intraoperative Sentinel Lymph Node Imprint Cytology Analysis for Metastasis in Patients with Melanoma.

Since there are no standardized protocols regarding the detection of microscopic melanoma deposits in sentinel lymph nodes (SLN), the aim of this study was to present our experience with intraoperative cytological evaluation of SLN in patients with melanoma. The study included 475 SLN biopsies (SLNB) from 201 patients with primary cutaneous melanoma of intermediate thickness. Each lymph node was cut in half; touch imprint cytology (TIC) preparations of all cut surfaces were performed and stained according to a modified May-Grünwald-Giemsa method. The results were compared to definitive postoperative histology. Twenty of 25 SLNB positive on TIC proved to be metastatic when compared to definitive histology. Most of 32 SLN that were suspicious but not diagnostic on TIC were proven negative (23/32, 71.8%), while 7 nodes had metastases (one micrometastasis and one with isolated tumor cells only). The majority (94%) of SLNBs negative on TIC remained negative on final histology, while 6% or 25 nodes were positive, mostly with micrometastases or isolated tumor cells (17/25). In frozen sections performed in cases of suspicious or positive SLN cytology, metastasis was confirmed in 80% of positive and in 21.9% of suspicious TIC. Altogether, 49% (27/55) of positive SLNB were identified intraoperatively in 57% (24/42) of patients, and in those cases a complete regional lymph node dissection was performed in the first step. TIC assessment of SLNB with 99% specificity and 57% sensitivity for intraoperative identification of metastasis is useful and beneficial for avoiding a second operative procedure.

Rapid Fatal Acute Peripheral T-Cell Lymphoma Associated With IgG Plasma Cell Leukemia and IgA Hypergammaglobulinemia.

Simultaneous occurrence of T-cell and B-cell neoplasms is rare, and etiologic relationships between these 2 malignancies are poorly understood. We describe the case of a 66-year-old woman who was admitted to the hospital because of fever, hemoptysis, lymphadenopathy, and skin rash. Enlarged lymph nodes in axillary, pectoral, paratracheal, and periportal regions as well as slight hepatomegaly and splenomegaly were confirmed. A peripheral blood smear revealed rouleaux formation and numerous circulating plasma cells, with plasmacytoid lymphocytes. Immunofixation-electrophoresis detected a monoclonal band defined as immunoglobulin (IgG)-lambda light chains with broad-band polyclonal IgA. The patient died from abrupt splenic rupture before diagnostic work-up was finished. Postmortem examination revealed infiltration of atypical lymphoid cells exhibiting high proliferative activity admixed with typical and atypical plasma cells in several organs. Thus, plasma cell leukemia (IgG-lambda) as a rare and aggressive variant of plasma cell myeloma in the present case was associated with aggressive peripheral T-cell lymphoma and polyclonal (IgA) plasmacytosis.