Intramuscular myxoma: unusual observation of spontaneous tumor size shrinkage.

Soft tissue tumors, whether benign or malignant, may grow over time or remain stable, but they usually do not spontaneously decrease in size. However, there are exceptions, such as inflammatory conditions, desmoid tumors, or benign cysts. Intramuscular myxomas are benign soft tissue tumors that typically present as a solitary, slow-growing, painless mass. They are generally treated by surgical resection, after which recurrence is rare. Here, we present a brief series of three unusual cases of intramuscular myxomas that spontaneously decreased in size. They were located in the cervical region, the right lower extremity, and the paravertebral lumbar region. Imaging findings and percutaneous biopsies confirmed the diagnosis in all cases. Follow-up imaging showed a spontaneous reduction in lesion volume over time, far exceeding the amount of tissue sample removed during biopsy. This unusual observation of spontaneous shrinkage may call into question the subsequent therapeutic approach to these lesions.

Injectable chitosan hydrogel effectively controls lesion growth in a venous malformation murine model.

PURPOSE: The purpose of this study was to evaluate the safety and efficacy of intralesional injection of chitosan hydrogel (CH) combined with sodium tetradecyl sulfate (STS) to sclerose and embolize venous malformations (VMs) by comparison with 3% STS foam and placebo in a mouse model. MATERIALS AND METHODS: Subcutaneous VMs were created by injecting HUVEC_TIE2-L914F cells, mixed with matrigel, into the back of athymic mice (Day [D] 0). After VM-like lesions were established at D10, 70 lesions were randomly assigned to one of six treatment groups (untreated, saline, 3% STS-foam, CH, 1% STS-CH, 3% STS-CH). For 3% STS-foam, the standard Tessari technique was performed. VMs were regularly evaluated every 2-3 days to measure lesion size until the time of collection at D30 (primary endpoint). At D30, VM lesions including the matrigel plugs were culled and evaluated by histological analysis to assess vessel size, chitosan distribution and endothelial expression. One-way analysis of variance (ANOVA) test was performed to compare quantitative variables with normal distribution, otherwise Kruskal-Wallis test followed by pairwise comparisons by a Wilcoxon rank sum test was performed. RESULTS: All VMs were successfully punctured and injected. Six VMs injected with 3% STS-CH showed early skin ulceration with an extrusion of the matrigel plug and were excluded from final analysis. In the remaining 64 VMs, skin ulceration occurred on 26 plugs, resulting in the loss of three 3% STS-foam and one 1% STS-CH plugs. Both chitosan formulations effectively controlled growth of VMs by the end of follow-up compared to untreated or 3% STS-foam groups (P < 0.05). Vessel sizes were smaller with both CH formulations compared to untreated and saline groups (P < 0.05). Additionally, there were smaller vascular channels within the 1% STS-CH group compared to the 3% STS-foam group (P < 0.05). CONCLUSION: Chitosan's ability to control the growth of VMs suggests a promising therapeutic effect that outperforms the gold standard (STS-foam) on several variables.

Recurrent and novel fusions detected by targeted RNA sequencing as part of the diagnostic workflow of soft tissue and bone tumours.

The identification of gene fusions has become an integral part of soft tissue and bone tumour diagnosis. We investigated the added value of targeted RNA-based sequencing (targeted RNA-seq, Archer FusionPlex) to our current molecular diagnostic workflow of these tumours, which is based on fluorescence in situ hybridisation (FISH) for the detection of gene fusions using 25 probes. In a series of 131 diagnostic samples targeted RNA-seq identified a gene fusion, BCOR internal tandem duplication or ALK deletion in 47 cases (35.9%). For 74 cases, encompassing 137 FISH analyses, concordance between FISH and targeted RNA-seq was evaluated. A positive or negative FISH result was confirmed by targeted RNA-seq in 27 out of 49 (55.1%) and 81 out of 88 (92.0%) analyses, respectively. While negative concordance was high, targeted RNA-seq identified a canonical gene fusion in seven cases despite a negative FISH result. The 22 discordant FISH-positive analyses showed a lower percentage of rearrangement-positive nuclei (range 15-41%) compared to the concordant FISH-positive analyses (>41% of nuclei in 88.9% of cases). Six FISH analyses (in four cases) were finally considered false positive based on histological and targeted RNA-seq findings. For the EWSR1 FISH probe, we observed a gene-dependent disparity (p = 0.0020), with 8 out of 35 cases showing a discordance between FISH and targeted RNA-seq (22.9%). This study demonstrates an added value of targeted RNA-seq to our current diagnostic workflow of soft tissue and bone tumours in 19 out of 131 cases (14.5%), which we categorised as altered diagnosis (3 cases), added precision (6 cases), or augmented spectrum (10 cases). In the latter subgroup, four novel fusion transcripts were found for which the clinical relevance remains unclear: NAB2::NCOA2, YAP1::NUTM2B, HSPA8::BRAF, and PDE2A::PLAG1. Overall, targeted RNA-seq has proven extremely valuable in the diagnostic workflow of soft tissue and bone tumours.

Has Propranolol Eradicated the Need for Surgery in the Management of Infantile Hemangioma?

BACKGROUND: To assess the impact of propranolol as the first-line treatment of infantile hemangioma (IH) on the need for surgery in the management of IH. METHODS: Retrospective study of 420 patients, with IH, referred to our multidisciplinary center between January 2005 and August 2014. Clinical data including sex, age at first consultation and at treatment initiation, location, size, number, aspect, and complication of IH, as well as the type of treatment were collected. Statistical analyses were conducted considering each patient and each tumor independently. RESULTS: A total of 625 IH(420 patients (P))were reviewed, 113 patients had more than one IH (26.91%). Median age at first consultation was 7 months old. Overall, 243 patients were treated (57.86%) using either surgery (n=128 P/141 IH), propranolol (n=79 P/89 IH), corticosteroids (n=51 P/56 IH), and/or laser (n=34 P /36 IH). Propranolol was effective in all but 2 infants with IH. Seven patients (n=7/79 P; 8.86%) initially treated with propranolol, still required surgery, in contrast to 18 patients (n=18/51 P; 35.29%) initially treated with corticosteroids, and 103 patients (n=103/290 P; 35.51%) with no medical treatment. Since the availability of propranolol, patients were less likely to undergo surgery (48 P versus 80 P; P-Value < 0.001). This demonstrated that the use of propranolol reduced the need for surgery (P-Value < 0.001 with an OR of 0.177: CI 95% 0.079-0.396). CONCLUSION: Propranolol has dramatically reduced the need for surgery, regarding indications and number of patients. Surgical correction remains important for sequelae management, non-responders or strawberry-like IH.

Somatic Loss-of-Function PIK3R1 and Activating Non-hotspot PIK3CA Mutations Associated with Capillary Malformation with Dilated Veins (CMDV).

Common capillary malformations are red vascular skin lesions, most commonly associated with somatic activating GNAQ or GNA11 mutations. We focused on capillary malformations lacking such a mutation to identify previously unreported genetic causes. We used targeted next-generation sequencing on 82 lesions. Bioinformatic analysis allowed the identification of 9 somatic pathogenic variants in PIK3R1 and PIK3CA, encoding for the regulatory and catalytic subunits of phosphoinositide 3-kinase, respectively. Recharacterization of these lesions unraveled a common phenotype: a pale capillary malformation associated with visible dilated veins. Primary endothelial cells from 2 PIK3R1-mutated lesions were isolated, and PI3k-Akt-mTOR and RAS-RAF-MAPK signaling were assessed by western blot. This unveiled an abnormal increase in Akt phosphorylation, effectively reduced by PI3K pathway inhibitors, such as mTOR, Akt, and PIK3CA inhibitors. The effects of mutant PIK3R1 were further studied using zebrafish embryos. Endothelium-specific expression of PIK3R1 mutants resulted in abnormal development of the posterior capillary-venous plexus. In summary, capillary malformation associated with visible dilated veins emerges as a clinical entity associated with somatic pathogenic variants in PIK3R1 or PIK3CA (nonhotspot). Our findings suggest that the activated Akt signaling can be effectively reversed by PI3K pathway inhibitors. In addition, the proposed zebrafish model holds promise as a valuable tool for future drug screening aimed at developing patient-tailored treatments.

Diagnostic Superiority of Dual-Time Point [18F]FDG PET/CT to Differentiate Malignant from Benign Soft Tissue Tumors.

[18F]FDG PET/CT is used in the workup of indeterminate soft tissue tumors (STTs) but lacks accuracy in the detection of malignant STTs. The aim of this study is to evaluate whether dual-time point [18F]FDG PET/CT imaging (DTPI) can be useful in this indication. In this prospective study, [18F]FDG PET/CT imaging was performed 1 h (t1) and 3 h (t2) after injection. Tumor uptake (SUVmax) was calculated at each time point to define a retention index (RI) corresponding to the variation between t1 and t2 (%). Sixty-eight patients were included, representing 20 benign and 48 malignant tumors (including 40 sarcomas). The RI was significantly higher in malignant STTs than in benign STTs (median: +21.8% vs. -2%, p < 0.001). An RI of >14.3% predicted STT malignancy with a specificity (Sp) of 90% and a sensitivity (Se) of 69%. An SUVmaxt1 of >4.5 was less accurate with an Sp of 80% and an Se of 60%. In a subgroup of tumors with at least mild [18F]FDG uptake (SUVmax ≥ 3; n = 46), the RI significantly outperformed the diagnostic accuracy of SUVmax (AUC: 0.88 vs. 0.68, p = 0.01). DTPI identifies malignant STT tumors with high specificity and outperforms the diagnostic accuracy of standard PET/CT.

Epithelioid Fibrous Histiocytoma with CARS-ALK Fusion: First Case Report.

Epithelioid fibrous histiocytoma (EFH) is a type of uncommon skin tumor mostly harboring Anaplastic Lymphoma Kinase (ALK) gene rearrangement, with different fusion partners reported. Whether this tumor is a separate entity or has a relationship with conventional fibrous histiocytomas is still a matter of debate. Benign course is the rule after complete surgical excision. A rare subtype of EFH with fusiform cells has been described, with specific fusion partners. Inflammatory myofibroblastic tumor (IMT) is a type of soft tissue tumor rarer than EFH, and it can display distant metastases. Some cases of primary cutaneous IMT included two with Cysteinyl-tRNA Synthetase 1 (CARS)-ALK rearrangement. IMT can have the same fusion partners as EFH, such as DCTN1, TMP3 or EML4 genes. We report the case of a 42-year-old woman presenting EFH with fusiform morphology harboring CARS-ALK fusion and discuss similarities and differences with IMT.

Primary extrarenal rhabdoid tumour of the liver: a case report and literature review.

Background: Extrarenal rhabdoid tumours (ERT) are highly aggressive tumours that are poorly responsive to standard cytotoxic chemotherapy and are associated with a grim prognosis. Primary ERT of the liver are most commonly observed in early childhood and exceptionally rare later in life. Case presentation: We report the case of a 16-year-old male patient, presenting with flu-like symptoms after his second COVIDvaccination. During the work-up, a large solid liver lesion was incidentally discovered upon abdominal ultrasound examination. Pathological examination rendered the diagnosis of primary ERT of the liver, characterized by the loss of expression of INI-1 protein, encoded by the SMARCB1 gene. We summarized and discuss the existing literature by reviewing 53 pediatric and 6 adult cases, including the histological features treatment and outcomes of primary hepatic ERT. Conclusion: Primary ERT of the liver are usually not associated with specific signs or symptoms, making the diagnosis very challenging. As ERT are associated with a high metastatic rate, delayed diagnoses lead to increased mortality, as complete resection is not possible in advanced-stage cases. Therefore, early diagnoses, enabling complete resection of the tumour are crucial to improve patient outcomes. Of interest, primary ERT of the liver, is associated with biallelic loss of the SMARCB1 (SWI/ SNF Related, Matrix Associated, Actin Dependent Regulator Of Chromatin, Subfamily B, Member 1) gene, a potential target for cancer therapeutics. This is, to our knowledge, the first case of a hepatic rhabdoid tumour treated with liver transplantation.

Immunohistochemical Profiling of Corneas With Fuchs Endothelial Corneal Dystrophy.

PURPOSE: Fuchs endothelial corneal dystrophy (FECD) is the leading indication for endothelial keratoplasty. Further insight into its pathophysiology is needed to develop alternative therapies. METHODS: Sixteen genes from a previous microarray expression experiment (FECD vs. normal) were validated using immunohistochemistry on paraffin-embedded corneas (n = 6 FECD, n = 6 normal). The results were quantified manually and semiautomatically. RESULTS: A higher percentage of corneal endothelial cells stained for alpha-smooth muscle actin (αSMA), cytokeratin 7, and superoxide dismutase 3 in FECD versus normal [odds ratios (ORs) of 60.90, 41.70, and 15.16, respectively, P < 0.001]. Dot-like staining for major histocompatibility complex, class II, DR alpha was present in FECD, but not in normal. Higher percentages of stromal cells in FECD versus normal stained for αSMA (OR = 864.26, P < 0.001), brain-derived neurotrophic factor (BDNF, OR = 6.34, P = 0.005), fibroblast growth factor 7 (FGF-7, OR = 2.76, P = 0.011), FGF-9 (OR = 5.97, P < 0.001), receptor FGFR-3 (OR = 13.90, P = < 0.001), and serum amyloid A1 (OR = 3.45, P = 0.023). Higher percentages of corneal epithelial cells stained for αSMA (OR = 2.20, P = 0.006) and BDNF (OR = 3.94, P < 0.001) in FECD versus normal. CONCLUSIONS: These results support a role for epithelial-mesenchymal transition (αSMA), oxidative stress (superoxide dismutase 3), and major histocompatibility complex, class II, DR alpha cells with dendritic morphology in the pathophysiology of FECD. Furthermore, corneal stromal cells express trophic molecules (BDNF and FGFs) and markers of chronic inflammation (serum amyloid A1) in FECD.

Identification of Circulating Fibrocytes and Dendritic Derivatives in Corneal Endothelium of Patients With Fuchs' Dystrophy.

Purpose: Fuchs' endothelial corneal dystrophy (FECD) is a degenerative eye disorder affecting 4% of Americans older than 40. It is the leading indication for corneal endothelial (CE) transplantation for which there is a global donor shortage. This study aimed to gain further insight into the pathophysiology of FECD and identify targets for nonsurgical therapy. Methods: CE from patients with late-onset FECD was compared with that of normal controls using microarray expression analysis (n = 4 FECD, n = 4 normal), reverse transcriptase quantitative PCR (n = 9 FECD, n = 8 normal), and immunohistology (n = 55 FECD, n = 15 normal). Results: This led to the identification of circulating fibrocytes and their dendritic derivatives in all examined CE samples with FECD (in all clinical stages of symptomatic FECD and independent of prior cataract surgery). These cells were not present in normal CE. In this study we characterize their morphology, protein expression profile, number, and localization within the CE layer of patients with FECD. Conclusions: Circulating fibrocytes and their dendritic derivatives are a new aspect of FECD that deserves further investigation. Because they are known to cause fibrosis in a variety of organs, they may play a similar role in FECD and might be a valuable target for nonsurgical therapy.