Limited Accuracy of Pan-Trk Immunohistochemistry Screening for NTRK Rearrangements in Follicular-Derived Thyroid Carcinoma.

Patients with advanced thyroid cancer harboring NTRK rearrangements can be treated with highly effective selective inhibitors. Immunohistochemistry (IHC) analysis, to detect Trk protein expression, represents an appealing screening strategy for NTRK rearrangements, but its efficacy has been poorly explored in thyroid cancer. The aim of this study is to investigate the diagnostic utility of Trk IHC in the identification of NTRK rearrangements. A series of 26 follicular-derived thyroid tumors, positive for NTRK rearrangements, and 28 NTRK fusion-negative controls were retrospectively analyzed by IHC using the pan-Trk monoclonal antibody (clone EPR17341) on the Ventana system. Area under the curve (AUC), sensitivity and specificity were calculated by ROC analysis. Trk expression was detected in 25 samples, including 22 out of the 26 NTRK-rearranged (84.6%) and three out of 28 NTRK-negative samples (10.7%). Four out of twenty-six NTRK-rearranged thyroid tumors were negative for Trk expression (15.4%), all carrying the ETV6/NTRK3 fusion. The AUC, sensitivity and specificity were 0.87, 0.85 and 0.89, respectively. A screening based on IHC analysis showed limited sensitivity and specificity in the identification of NTRK-rearranged tumors. Since falsely negative results could preclude the administration of effective targeted drugs, alternative detection strategies should be considered for thyroid cancer.

Unusual presentation of extranodal diffuse large B-cell lymphoma in a solid-organ recipient during long-term immunosuppressive treatment.

INTRODUCTION: Posttransplant lymphoproliferative disorders (PTLDs) refer to a group of diseases, including diffuse large B-cell lymphoma (DLBCL), that develop after solid organ transplantation or hematopoietic stem cell transplantation. Extranodal involvement in PTLDs is common. Reports about exclusive bone marrow involvement are rare. CASE DESCRIPTION: A 70-year-old woman, who had undergone kidney transplantation in 2018, was diagnosed with exclusively extranodal, Epstein-Barr virus-negative DLBCL, with bone marrow and spleen involvement, during long-term immunosuppression. She achieved complete remission with combined immunochemotherapy and temporary hold of immunosuppression. CONCLUSIONS: This case shows an uncommon clinical presentation of DLBCL, which was challenging to diagnose, being entirely extranodal. The favorable clinical course relied on timely diagnosis and a multidisciplinary approach. Long-term consequences of posttransplant immunosuppression require a high level of suspicion for an appropriate management, aimed at preserving the graft while eradicating the lymphoproliferative disorder.

MAP2K1-driven mixed Langerhans cell histiocytosis, Rosai-Dorfman-Destombes disease and Erdheim-Chester disease, clonally related to acute myeloid leukemia.

Mixed histiocytoses are a rare and recently recognized subset of histiocytic disorders that may involve the skin, characterized by the synchronous or metachronous development of lesions with Langerhans and/or non-Langerhans cell histiocytosis histopathological features. Around 10% of patients diagnosed with histiocytosis may develop a hematological malignancy, often with dramatic prognostic consequences. We hereby describe the exceptional case of a patient developing a MAP2K1-driven mixed histiocytosis with Langerhans cell histiocytosis, Rosai-Dorfman-Destombes disease, and Erdheim-Chester disease features and cutaneous involvement, progressing to a fatal and clonally-related acute myeloid leukemia. We reviewed the literature on similar cases and discussed the histopathological difficulties in their diagnosis and their clinical-pathological features.

Putative Role of Circulating Human Papillomavirus DNA in the Development of Primary Squamous Cell Carcinoma of the Middle Rectum: A Case Report.

Here we present the case of a patient affected by rectal squamous cell carcinoma in which we demonstrated the presence of Human Papillomavirus (HPV) by a variety of techniques. Collectively, the virus was detected not only in the tumor but also in some regional lymph nodes and in non-neoplastic mucosa of the upper tract of large bowel. By contrast, it was not identifiable in its common sites of entry, namely oral and ano-genital region. We also found HPV DNA in the plasma-derived exosome. Next, by in vitro studies, we confirmed the capability of HPV DNA-positive exosomes, isolated from the supernatant of a HPV DNA positive cell line (CaSki), to transfer its DNA to human colon cancer and normal cell lines. In the stroma nearby the tumor mass we were able to demonstrate the presence of virus DNA in the stromal compartment, supporting its potential to be transferred from epithelial cells to the stromal ones. Thus, this case report favors the notion that human papillomavirus DNA can be vehiculated by exosomes in the blood of neoplastic patients and that it can be transferred, at least in vitro, to normal and neoplastic cells. Furthermore, we showed the presence of viral DNA and RNA in pluripotent stem cells of non-tumor tissue, suggesting that after viral integration (as demonstrated by p16 and RNA in situ hybridization positivity), stem cells might have been activated into cancer stem cells inducing neoplastic transformation of normal tissue through the inactivation of p53, p21, and Rb. It is conceivable that the virus has elicited its oncogenic effect in this specific site and not elsewhere, despite its wide anatomical distribution in the patient, for a local condition of immune suppression, as demonstrated by the increase of T-regulatory (CD4/CD25/FOXP3 positive) and T-exhausted (CD8/PD-1positive) lymphocytes and the M2 polarization (high CD163/CD68 ratio) of macrophages in the neoplastic microenvironment. It is noteworthy that our findings depicted a static picture of a long-lasting dynamic process that might evolve in the development of tumors in other anatomical sites.

Diagnosis of idiopathic pulmonary fibrosis by virtual means using "IPFdatabase"- a new software.

BACKGROUND: The diagnostic algorithm for idiopathic pulmonary fibrosis (IPF) guidelines has some shortcomings. The aim of the present study was to develop a novel software, "IPFdatabase", that could readily apply the diagnostic criteria per IPF guidelines and make a 'virtual' diagnosis of IPF. METHODS: Software was developed as a step-by-step compilation of necessary information according to guidelines to enable a diagnosis of IPF. Software accuracy was validated primarily by comparing software diagnoses to those previously made at a Center for Interstitial Lung Diseases. RESULTS: Clinical validation on 98 patients (68 male, age 61.0 ±â€¯8.5 years), revealed high software accuracy for IPF diagnosis when compared to historical diagnoses (sensitivity 95.5%, specificity 96.2%; positive predictive value 95.5%, negative predictive value 96.2%). A general radiologist and a general pathologist reviewed relevant data with and without the new software: interobserver agreement increased when they used the IPFdatabase (kappa 0.18 to 0.64 for radiology, 0.13 to 0.59 for pathology). CONCLUSION: IPFdatabase is a useful diagnostic tool for typical cases of IPF, and potentially restricts the need for MDDs to atypical and complex cases. We propose this web-designed software for instant accurate diagnosis of IPF by virtual means and for educational purposes; the software is readily accessed with mobile apps, allows incorporation of updated version of guidelines, can be utilized for gathering data useful for future studies and give physicians rapid feedback in daily practice.

A Respiratory Syncytial Virus Vaccine Vectored by a Stable Chimeric and Replication-Deficient Sendai Virus Protects Mice without Inducing Enhanced Disease.

Respiratory syncytial virus (RSV) is a major cause of severe respiratory infections in children and elderly people, and no marketed vaccine exists. In this study, we generated and analyzed a subunit vaccine against RSV based on a novel genome replication-deficient Sendai virus (SeV) vector. We inserted the RSV F protein, known to be a genetically stable antigen, into our vector in a specific way to optimize the vaccine features. By exchanging the ectodomain of the SeV F protein for its counterpart from RSV, we created a chimeric vectored vaccine that contains the RSV F protein as an essential structural component. In this way, the antigen is actively expressed on the surfaces of vaccine particles in its prefusion conformation, and as recently reported for other vectored vaccines, the occurrence of silencing mutations of the transgene in the vaccine genome can be prevented. In addition, its active gene expression contributes to further stimulation of the immune response. In order to understand the best route of immunization, we compared vaccine efficacies after intranasal (i.n.) or intramuscular (i.m.) immunization of BALB/c mice. Via both routes, substantial RSV-specific immune responses were induced, consisting of serum IgG and neutralizing antibodies, as well as cytotoxic T cells. Moreover, i.n. immunization was also able to stimulate specific mucosal IgA in the upper and lower respiratory tract. In virus challenge experiments, animals were protected against RSV infection after both i.n. and i.m. immunization without inducing vaccine-enhanced disease. Above all, the replication-deficient SeV appeared to be safe and well tolerated.IMPORTANCE Respiratory syncytial virus (RSV) is a major cause of respiratory diseases in young children and elderly people worldwide. There is a great demand for a licensed vaccine. Promising existing vaccine approaches based on live-attenuated vaccines or viral vectors have suffered from unforeseen drawbacks related to immunogenicity and attenuation. We provide a novel RSV vaccine concept based on a genome replication-deficient Sendai vector that has many favorable vaccine characteristics. The specific vaccine design guarantees genetic stability of the transgene; furthermore, it supports a favorable presentation of the antigen, activating the adaptive response, features that other vectored vaccine approaches have often had difficulties with. Wide immunological and pathological analyses in mice confirmed the validity and efficacy of this approach after both parenteral and mucosal administration. Above all, this concept is suitable for initiating clinical studies, and it could also be applied to other infectious diseases.

MicroRNAs sequencing unveils distinct molecular subgroups of plasmablastic lymphoma.

Plasmablastic lymphoma (PBL) is an aggressive lymphoma, often arising in the context of immunodeficiency and associated with Epstein-Barr virus (EBV) infection. The most frequently detected genetic alteration is the deregulation of MYC gene through the translocation - t(8;14)(q24;q32). The diagnosis of PBL is often challenging because it has an overlap in morphology, immunophenotype, cytogenetics and virus association with other lymphomas and plasma cell neoplasms; further, its molecular basis remains elusive. In the present study we aimed to better define the possible contribution of EBV infection as well as miRNA deregulation in PBL pathogenesis. We studied 23 cases of PBL, 19 Burkitt lymphomas (BL), and 17 extra-medullary plasmacytoma (EMPC). We used qPCR and immunohistochemistry to assess EBV latency patterns, while micro-RNA (miRNA) profiling was performed by next generation sequencing (Illumina) and validated by qPCR. Our analysis revealed a non-canonical EBV latency program with the partial expression of some proteins characterizing latency II and the activation of an abortive lytic cycle. Moreover, we identified miRNA signatures discriminating PBL from BL and EMPC. Interestingly, based on the miRNA profile, PBL appeared constituted by two discrete subgroups more similar to either BL or EMPC, respectively. This pattern was confirmed in an independent set of cases studied by qPCR and corresponded to different clinico-pathological features in the two groups, including HIV infection, MYC rearrangement and disease localization. In conclusion, we uncovered for the first time 1) an atypical EBV latency program in PBL; 2) a miRNA signature distinguishing PBL from the closest malignant counterparts; 3) the molecular basis of PBL heterogeneity.

Carbonic anhydrase IX is a marker of hypoxia and correlates with higher Gleason scores and ISUP grading in prostate cancer.

BACKGROUND: Carbonic anhydrase IX is a member of α-carbonic anhydrases that is preferentially expressed in solid tumors. It enables bicarbonate transport across the plasma membrane, neutralizing intracellular pH and conferring to cancer cells a survival advantage in hypoxic/acidic microenvironments. Overexpression of carbonic anhydrase IX in cancer tissues is regulated by hypoxia inducible factor 1α - mediated transcription and the enzyme is considered a marker of tumor hypoxia and poor outcome. The role of carbonic anhydrase IX in prostate cancer has not been fully clarified and controversy has arisen on whether this enzyme is overexpressed in hypoxic prostate cancer tissues. METHODS: We analyzed the expression of carbonic anhydrase IX and hypoxia inducible factor 1α in two prostate cancer cell lines, LNCaP and PC-3, and in 110 cancer biopsies, by western blotting and immunocyto/histochemistry. RESULTS: In LNCaP and PC-3 cells, carbonic anhydrase IX was mostly cytoplasmic/nuclear, with very limited membrane localization. Nuclear staining became stronger under hypoxia. When we analyzed carbonic anhydrase IX expression in human prostate cancer biopsies, we found that protein staining positively correlated with hypoxia inducible factor 1α and with Gleason pattern and score, as well as with the novel grading system proposed by the International Society of Urological Pathology for prostate cancer. Once more, carbonic anhydrase IX was mainly cytoplasmic in low grade carcinomas, whereas in high grade tumors was strongly expressed in the nucleus of the neoplastic cell. An association between carbonic anhydrase IX expression level and the main clinic-pathological features involved in prostate cancer aggressiveness was identified. CONCLUSIONS: There was a statistically significant association between carbonic anhydrase IX and hypoxia inducible factor 1α in prostate cancer tissues, that identifies the enzyme as a reliable marker of tumor hypoxia. In addition, carbonic anhydrase IX expression positively correlated with prostate cancer grading and staging, and with outcome, suggesting that the protein may be an independent prognosticator for the disease. The nuclear translocation of the enzyme in hypoxic cancer cells may epitomize a biological switch of the tumor towards a less favorable phenotype.

A look into the evolution of Epstein-Barr virus-induced lymphoproliferative disorders: a case study.

OBJECTIVES: Epstein-Barr virus (EBV)-induced lymphoproliferative disorders (LPDs) are lymphoid proliferations arising as a result of the loss of an effective EBV-specific cytotoxic T-cell response. LPDs may occur for primary or acquired impairment of the immune system, as well as in some persons without documented immunodeficiency. METHODS: In this article, we describe the case of a human immunodeficiency virus-positive patient affected by an EBV-LPD of the stomach who developed a nodal diffuse large B-cell lymphoma with complex morphologic and molecular features. RESULTS: GeneScan analysis of the gastric specimen identified two different heavy-chain immunoglobulin gene (IGH) rearrangements characterized by a dominant peak of 285 base pairs (bp) in length and a smaller peak of 266 bp in length. In the lymph node sample, IGH evaluation also demonstrated two different peaks; however, the main peak corresponded to the minor peak detected in the EBV-LPD specimen at the diagnosis. In addition, a monoclonal immunoglobulin light chain gene (IGL) rearrangement was also found. We also demonstrated that the major peak in the stomach corresponded to the EBV-positive population observed in the histologic sections. CONCLUSIONS: This case may provide additional insights to better understanding the "hit-and-run" role for EBV in lymphomagenesis. However, we could not exclude that our findings represent the co-occurrence of two unrelated B-cell neoplasms rather than a progression from an EBV-positive neoplasm to an EBV-negative one.

Lymphatic Vascularization in Prostate Adenocarcinoma: Correlation with Tumor Grade, Androgen Withdrawal and Prognosis.

BACKGROUND/AIM: The lymphatic system plays an active role in the metastatic process by directly facilitating recruitment of cancer cells into the vessels. The present study aimed to assess the lymphatic vessel area and the lymphatic vessel density in prostate adenocarcinoma and to correlate these parameters with patients prognosis and outcome. PATIENTS AND METHODS: The lymphatic vessel area and the lymphatic vessel density were evaluated using the D2-40 monoclonal antibody in 153 patients with prostate adenocarcinoma who had been treated by radical prostatectomy, in comparison to 152 non-neoplastic controls. We also estimated the lymphatic vessel area in a set of 139 patients who had undergone radical prostatectomy after neoadjuvant treatment with combined androgen blockade. RESULTS: Lymphatic vessel area was higher in periglandular than in interglandular stroma, inversely correlated with tumor differentiation (in untreated patients) and was influenced by hormonal treatment. Lymphatic vessel density was not significantly different between the non-tumoral and the high-grade prostate intraepithelial neoplasm compartment, whereas it was higher in tumoral than in non-tumoral compartments, mainly in periglandular stroma. In addition, it increased in parallel to the tumor grade progression and positively correlated with all the main prognostic factors of prostate adenocarcinoma. CONCLUSION: The evaluation of lymphatic vessel density on radical prostatectomy with positive nodes may help to discriminate those patients at higher risk of developing an aggressive disease, which may need early androgen deprivation therapy to delay the worsening of clinical disease.

Translationally controlled tumor protein in prostatic adenocarcinoma: correlation with tumor grading and treatment-related changes.

Prostate cancer is the second leading cause of cancer-related death. The androgen deprivation therapy is the standard treatment for advanced stages. Unfortunately, virtually all tumors become resistant to androgen withdrawal. The progression to castration-resistance is not fully understood, although a recent paper has suggested translationally controlled tumor protein to be implicated in the process. The present study was designed to investigate the role of this protein in prostate cancer, focusing on the correlation between its expression level with tumor differentiation and response to treatment. We retrieved 292 prostatic cancer specimens; of these 153 had been treated only by radical prostatectomy and 139 had undergone radical prostatectomy after neoadjuvant treatment with combined androgen blockade therapy. Non-neoplastic controls were represented by 102 prostatic peripheral zone specimens. In untreated patients, the expression of the protein, evaluated by RT-qPCR and immunohistochemistry, was significantly higher in tumor specimens than in non-neoplastic control, increasing as Gleason pattern and score progressed. In treated prostates, the staining was correlated with the response to treatment. An association between protein expression and the main clinicopathological factors involved in prostate cancer aggressiveness was identified. These findings suggest that the protein may be a promising prognostic factor and a target for therapy.

Late hepatic metastasis from a duodenal gastrointestinal stromal tumor (29 years after surgery): report of a case and review of the literature.

Gastrointestinal stromal tumor (GIST) metastases are found most commonly in the liver, on average 16 to 38 months after resection of the primary tumor, even if some delayed hepatic metastases from GISTs have been described. We report a case of a man with a giant liver mass at computed tomography scan. In September 1984, the patient had undergone resection of a duodenal tumor, diagnosed as schwannoma. A liver biopsy revealed a neoplasm composed of epithelioid and spindled cells, immunohistochemically positive to c-kit and Dog-1. Reexamining the duodenal tumor resected in 1984, it was reclassified as GIST. Sequencing revealed the same mutation of the c-kit gene in both duodenal and hepatic lesions. To the best of our knowledge, this case represents the longest disease-free interval between a primary GIST and its metastasis. A brief review of the literature and an analysis of the potential prognostic role of particular c-kit mutations are also provided.

Amphicrine carcinoma of the ampullary region.

Amphicrine carcinoma is a peculiar tumor in which the cells have both exocrine and neuroendocrine differentiation, with mucus and neuroendocrine granules within the cytoplasm. In the 2010 WHO classification of tumors of the digestive tract, they have been included in the intermediate-grade malignant category of mixed adenoneuroendocrine carcinomas (MANECs). These tumors are extremely rare in the gastrointestinal tract. Four cases have been reported in the stomach, three in the pancreas, and one in the liver. To the best of our knowledge, this report describes the first case of amphicrine carcinoma in the ampullary region.

Human papillomavirus-related basaloid squamous cell carcinoma of the bladder associated with genital tract human papillomavirus infection.

Basaloid squamous cell carcinoma is a biologically aggressive neoplasm mainly found in the head and neck region. Recently, four cases of basaloid squamous cell carcinoma of the bladder have been reported, and three of them occurred in patients with neurogenic bladder, repeated catheterizations and human papillomavirus infection of the urinary tract. To the best of our knowledge, none of the patients affected by basaloid squamous cell carcinoma of the bladder described in the literature had documented genital involvement by human papillomavirus. Herein, we describe the case of a woman with neurogenic bladder affected by basaloid squamous cell carcinoma of the bladder and by a concomitant genital tract human papillomavirus infection.

Malignant rhabdoid tumor of the small intestine in adults: a brief review of the literature and report of a case.

A malignant rhabdoid tumor was first described as a subtype of Wilms tumor in 1978. The most frequent location of these tumors is the kidney, and they are common in childhood. The extrarenal localization of these tumors has been described mainly in the central nervous system (called atypical teratoid-rhabdoid tumors), liver, soft tissues and colon. Localization in the small intestine is uncommon and since the 1990s, only a few cases of malignant rhabdoid tumors in the small intestine have been reported. This tumor is very aggressive and the prognosis is poor. We herein present our personal experience with a rhabdoid tumor of the jejunum in a 76-year-old male, and also provide an analysis of the cases of malignant rhabdoid tumor of the small intestine previously described in the literature as for a brief review. We also compared the previous reports and our present case to try to identify prognostic factors.

Unusual presentation of primary T-cell lymphoblastic lymphoma: description of two cases.

BACKGROUND: T-cell lymphoblastic lymphoma comprises approximately 85-90% of all lymphoblastic lymphomas. It often arises as a mediastinal mass, and with bone marrow involvement. Presentation at other sites without nodal or mediastinal localization is uncommon. CASE REPORT: We describe clinical, histologic, immunohistochemical, and molecular features of two cases of primary T-cell lymphoblastic lymphoma arising respectively in uterine corpus and testis. The tumors were composed by medium to large cells, exhibiting a diffuse pattern of growth but sometimes forming indian files or pseudo-rosettes. The neoplastic cells strongly expressed TdT and T-cell markers in both uterine corpus and testis. However, the testis case also showed aberrant expression of B-cell markers, thus molecular biology was necessary to achieve a final diagnosis. T-cell receptor gene rearrangement analysis identified a T-cell origin. CONCLUSIONS: To the best of our knowledge, only one doubtful previous case of primary uterine T-cell lymphoblastic lymphoma and no previous cases of primary testicular T-cell lymphoblastic lymphoma have been reported. Due to the morphology of neoplastic cells, a challenging differential diagnosis with all the tumors belonging to the so-called small round blue cell tumor category is mandatory. In ambiguous lineage cases, molecular biology may represent an adequate tool to confirm diagnosis. VIRTUAL SLIDES: The virtual slide(s) for this article can be found here: http://www.diagnosticpathology.diagnomx.eu/vs/1559880973128230.