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We report a case of a 67-year-old male patient with a sinonasal tumor that showed areas of classic biphenotypic sinonasal sarcoma (BSNS) which in some sections sharply transitioned into high-grade rhabdomyosarcoma. Immunohistochemically, the conventional BSNS parts showed S100 protein, SMA, PAX7, and focal MyoD1 expression, whereas desmin and myogenin were negative. In contrast, the cells in high-grade areas expressed desmin, MyoD1, myogenin, and PAX7, while being negative for S100 protein and SMA. Using the Archer FusionPlex assay, the classical PAX3::MAML3 gene fusion was detected. FISH for PAX3 and MAML3 confirmed a break of these genes in both components. Despite aggressive therapy, the tumor progression resulted in the patient’s death. The herein presented case, together with 2 previously published cases of BSNS with high-grade transformation, helps to better understand this novel phenomenon. Although the risk for such transformation appears low, it has important clinical and diagnostic implications which are discussed.

Background Methods for identifying gene fusion events, such as fluorescence in situ hybridization (FISH), immunohistochemistry (IHC), and transcriptome analysis, are either single gene approaches or require bioinformatics expertise not generally available in clinical laboratories. We analytically validated a customized next-generation sequencing (NGS) panel targeting fusion events in 34 genes involving soft-tissue sarcomas. Methods Specimens included 87 formalin-fixed paraffin-embedded (FFPE) tissues with known gene fusion status. Isolated total nucleic acid was used to identify fusion events at the RNA level. The potential fusions were targeted by gene-specific primers, followed by primer extension and nested PCR to enrich for fusion candidates with subsequent bioinformatics analysis. Results The study generated results using the following quality metrics for fusion detection: (a) ≥100 ng total nucleic acid, (b) RNA average unique start sites per gene-specific primer control ≥10, (c) quantitative PCR assessing input RNA quality had a crossing point Conclusions The test validation study demonstrated analytical sensitivity of 98.7% and analytical specificity of 90.0%. The NGS-based panel generated highly concordant results compared to alternative testing methods.

Purpose of review Although tumors with nerve sheath differentiation are vast, the main clinically significant problems faced by the pathologist are the separation of malignant peripheral nerve sheath tumors (MPNSTs) from histologic mimics, the diagnosis of neurofibromatous neoplasms with atypical features, and the separation of cutaneous neurofibromatous neoplasms from melanoma. This review briefly discusses a variety of common nerve sheath tumors and summarizes recent advances on these diagnostic fronts. Recent findings Much of recent work has focused on abnormalities in polycomb repressive complex 2, and the ways in which these abnormalities may be exploited in the diagnosis of MPNSTs. Progress has been made in the diagnostic and clinical understanding of atypical neurofibromatous neoplasms and low-grade MPNSTs. A number of reports have explored the diagnostic distinction between cutaneous neurofibroma and melanoma. Summary New discoveries show promise in the diagnosis of peripheral nerve sheath tumors, but challenges - old and new - remain.

Encapsulation of bacteria into a polymer matrix can potentially enhance the delivery of probiotics. In this study, we present a multilayer electrospun construct to facilitate enhanced delivery of probiotics, where the internal layer is loaded with bacterial cells and the external layers sandwich the internal layer for increased protection and potential mucoadhesion properties. In this proof of concept study, Lactobacillus rhamnosus GG (LGG), which is a robust and well-studied probiotic strain, was encapsulated into pullulan nanofibers, with two electrospun PLGA (Poly-lactic-co-glycolic acid) layers covering it. According to our in vitro study, there was a large decrease in the viability of LGG released from the monolayer sample (LGG:pullulan). However, the multilayer construct maintained excellent viability and an acceptable storage potential. Our in vivo competition study showed that LGG, delivered by multilayer construct, were able to survive intestinal transit and were recovered from all segments of the intestine. Not only did the multilayer construct perform as well as non-encapsulated spray-dried cells in terms of viability and establishment of LGG, but it also showed some cases of increased LGG colonization from fibers in jejunum and cecum compared to spray-dried LGG three days after dosage. We believe, the multilayer construct has the potential to enhance the delivery of the strains that require additional protection, and can benefit from mucus embedment with the help of the covering layers. Particularly, the use of electrospun fibers for the protection of next-generation probiotics sensitive to oxygen and/or gastric conditions could have major commercial interest.

Fibrous hamartoma of infancy (FHI) is a rare, benign lesion characterized as a tumor of myofibroblastic origin that has characteristic features of triphasic histology. FHI was first described in 1956 by Reye and formally named by Enzinger in 1965 [ [1] , [2] ]. The lesion is defined as a hamartoma due to the histologic presentation of disorganized mesenchymal, fibrous, and adipose tissue with absence of mitotic figures; this combination of derived tissue without evidence of anaplasia is diagnostic for FHI. These lesions typically arise as a single, solitary mass, are most commonly located on the extremities, trunk, sacrum, or scrotum and are typically 0.5 to 9.0 centimeters in size [ [3] , [4] ]. Only roughly 200 cases have been reported in the literature [ 3 ]. The majority of cases occur in young children; 91% of cases arise within the first year of life [ 4 ]. Males are more often affected in a ratio of 2.4:1 [ 4 ]. Roughly 20% of cases have been documented as congenital (3). Treatment is surgical excision, which is often curative; local recurrence is rare and incidence decreased by obtaining negative margins (8). We present a case of congenital FHI identified at birth.

We report 2 continuous flow HeartWareTM left ventricular assist devices successfully used in a patient with advanced heart failure of giant cell myocarditis origin in a biventricular configuration. Despite technical challenges of adapting a left ventricular assist device engineered for systemic pressure to function as a right ventricular assist device, the addition of dynamic banding on the right ventricular assist device outflow graft allowed successful adaptation of afterload. This patient has now been on biventricular configuration support for 9 years, and remains stable to this day.

Oral administration of probiotics is beneficial for restoring the intestinal microbial balance and for the treatment of gastrointestinal (GI) tract-related disorders. In the current era characterized by the development of next-generation probiotic microorganisms, which are typically less robust toward environmental challenges than the classically applied lactic acid producing probiotics, we anticipate a need for delivery of live organisms directly to the site where they need to colonize. Here, we thus present, for the first time, a proof of concept for using micrometer-sized polymeric containers, for the engineered delivery of probiotics, using spray dried Lactobacillus rhamnosus GG (LGG), as a model probiotic microorganism. To achieve colon-specific delivery, microcontainers are loaded with LGG and sealed with an enzyme-sensitive coating. A genipin-cross-linked chitosan coating is developed that (i) is stable at gastric and intestinal pH; (ii) has tunable swelling; and (iii) is degradable by the colon-specific bacterial enzymes. The chitosan-genipin coated microcontainers are evaluated in vitro, ex vivo, as well as in vivo in a rat model. Our results confirm that the genipin-cross-linked chitosan coating enables an effective local delivery in the cecum and colon without any premature release in the small intestine. Our findings suggest that the integration of modified polysaccharides with ingestible microdevices has great potential for controlled and site-specific delivery of live microorganisms.

Context.— Bone and soft tissue tumors are heterogeneous, diagnostically challenging, and often defined by gene fusions. Objective.— To present our experience using a custom 34-gene targeted sequencing fusion panel. Design.— Total nucleic acid extracted from formalin-fixed, paraffin-embedded (FFPE) tumor specimens was subjected to open-ended, nested anchored multiplex polymerase chain reaction and enrichment of 34 gene targets, thus enabling detection of known and novel fusion partners. Results.— During a 12-month period, 147 patients were tested as part of routine clinical care. Tumor percentage ranged from 10% to 100% and turnaround time ranged from 3 to 15 (median, 7.9) days. The most common diagnostic groups were small round blue cell tumors, tumors of uncertain differentiation, fibroblastic/myofibroblastic tumors, and adipocytic tumors. In-frame fusion transcripts were identified in 64 of 142 cases sequenced (45%): in 62 cases, the detection of a disease-defining fusion confirmed the morphologic impression; in 2 cases, a germline TFG-GPR128 polymorphic fusion variant was detected. Several genes in the panel partnered with multiple fusion partners specific for different diagnoses, for example, EWSR1, NR4A3, FUS, NCOA2, and TFE3. Interesting examples are presented to highlight how fusion detection or lack thereof was instrumental in establishing accurate diagnoses. Novel fusion partners were detected for 2 cases of solid aneurysmal bone cysts (PTBP1-USP6, SLC38A2-USP6). Conclusions.— Multiplex detection of fusions in total nucleic acid purified from FFPE specimens facilitates diagnosis of bone and soft tissue tumors. This technology is particularly useful for morphologically challenging entities and in the absence of prior knowledge of fusion partners, and has the potential to discover novel fusion partners.

One caveat of next-generation sequencing (NGS)-based clinical oncology testing is the high amount of input DNA required. We sought to develop a focused NGS panel that could capture hotspot regions in relevant genes requiring 0.5-10 ng input DNA. The resulting Penn Precision Panel (PPP) targeted 20 genes containing clinically significant variants relevant to many cancers. One hundred twenty-three samples were analyzed, including 83 solid tumor specimens derived from FFPE. Various input quantities of DNA (0.5-10 ng) were amplified with content-specific PCR primer pools, then sequenced on a MiSeq instrument (Illumina, Inc.) via paired-end, 2 × 186 base pair reads to an average read depth of greater than 6500x. Variants were detected using an in-house analysis pipeline. Clinical sensitivity and specificity were assessed using results from our previously validated solid tumor NGS panel; sensitivity of the PPP is 96.75% (387/400 variants) and specificity is 99.9% (8427/8428 base pairs). Variant allele frequencies (VAFs) are highly concordant across both assays (r = 0.98 p 0.0001). The PPP is a robust, clinically validated test optimized for low-yield solid tumor specimens, capturing a high percentage of clinically relevant variants found by larger commercially available NGS panels while using only 0.5-10 ng of input DNA.

Bacteria often live in communities of mixed species embedded in a self-produced extracellular matrix of polysaccharides, proteins and DNA, termed biofilms. The BioFlux microfluidic flow system is useful for studying biofilm formation in different media under flow. However, analyzing the architecture and maturation of biofilms under flow requires a proper seeding, which can prove difficult when working with bacteria of different sizes, motile bacteria or aiming for a high number of replicates. Here we developed an efficient protocol that exploits viscosity tuning and seeding indicator dyes to improve seeding and allow for high-throughput examination and visualization of consistent mono- and mixed-species biofilm developments under flow.