Gastric IgG4-related disease mimicking a gastrointestinal stromal tumor in a child: A case report.

BACKGROUND: Gastric IgG4-related disease (IgG4-RD) is rarely encountered in clinical practice, and especially more so among pediatric patients. To our knowledge, this is the first report of IgG4-RD presenting as a calcifying gastric mass in a child. We describe how this entity was difficult to differentiate from a gastrointestinal stromal tumor (GIST) imaging-based approaches. Therefore, this case highlights the importance of considering IgG4-RD in the differential diagnosis of gastric tumor before performing surgical resection, especially to distinguish it from malignancy to avoid unnecessary surgery. CASE SUMMARY: The patient suffered from epigastric pain for several days. Panendoscopy and computed tomography scan revealed a submucosal tumor. Differential diagnoses included GIST, leiomyoma, teratoma, and mucinous adenocarcinoma. However, laparoscopic proximal gastrectomy allowed for the definitive diagnosis of IgG4-related stomach disease. CONCLUSION: We emphasize the importance of considering IgG4-RD in the differential diagnosis of gastric submucosal tumors before performing surgical resection.

Self-Nanoemulsifying Drug Delivery System-Containing the Poorly Absorbed Drug - Valsartan in Post-Bariatric Surgery.

Purpose: Morbid obesity and its related metabolic syndrome are an important health issue. Recently, sleeve gastrectomy (SG) and Roux-en-Y gastric bypass (RYGB) have accounted for the most popular bariatric surgeries. Valsartan (VST) is a common hypertension drug, and nano-carriers can increase its solubility and bioavailability. This study aims to explore the nano-VST formula in bariatric surgery subjects. Methods: High-fat fed animals were used as obese models. Operations were performed according to a standardized protocol. The drug was administrated by gavage, and blood samples were taken by serial tail vein sampling. Caco-2 cells were used for examining cell viability and drug uptake. A self-nano-emusifying drug delivery system (SNEDDS) formula was composed of sefsol-218, RH-40 and propylene glycol by a specified ratio, while high-performance liquid chromatography (HPLC) was used for determining drug concentrations. Results: Post-operatively, subjects that underwent RYGB lost more body weight compared to the SG group. The SNEDDS did not exhibit cytotoxicity after adequate dilution, and the cytotoxicity was not related to VST dose. A better cellular uptake of SNEDDS was observed in vitro. The SNEDDS formula achieved a diameter of 84 nm in distilled water and 140 nm in simulated gastric fluid. In obese animals, the maximum serum concentration (Cmax) of VST was increased 1.68-folds by SNEDDS. In RYGB with SUS, the Cmax was reduced to less than 50% of the obese group. SNEDDS increased the Cmax to 3.5 folds higher than SUS and resulted in 3.28-folds higher AUC0-24 in the RYGB group. Fluorescence imaging also confirmed a stronger signal of SNEDDS in the gastrointestinal mucosa. SNEDDS accumulated a higher drug concentration than suspension alone in the liver of the obese group. Conclusion: SNEDDS could reverse the VST malabsorption in RYGB. Further studies are mandatory to clarify post-SG change of drug absorption.

Clinical presentations and molecular studies of invasive renal epithelioid angiomyolipoma.

PURPOSE: Epithelioid angiomyolipoma (EAML) is a rare variant of renal angiomyolipoma with malignant potential, and the cytogenetic and clinical behavior of EAML remains a challenging issue. METHODS: We retrospectively analyze the clinical courses of five EAML, the use of everolimus on metastatic EAML, and next-generation sequencing (NGS) and polymerase chain reaction (PCR) studies to investigate the gene mutation of TSC and the impact of PI3K/Akt/mTOR signaling pathway in metastatic EAML. RESULTS: The mean age was 37.8 years, mean tumor size was 13 cm, all patients received radical nephrectomy, one stage IV patient received neoadjuvant mTOR inhibitor management, and one patient with high mitotic activity developed metastasis 1 year after nephrectomy. NGS assay showed a frameshift gene mutation of TSC2 in chromosome 16. PCR array for the mRNA alterations in PI3K/Akt/mTOR signaling pathway of EAML showed high expression of PIP3, AKT, TSC1, mTOR, PDK1, P70, 4E-BP1 and elF4E. CONCLUSION: EAML of the kidney is a specific type of renal AML with malignant potentials, where around 22% of the patients present with invasion or metastasis. Higher mitotic activities indicate a greater metastatic potential, with radical nephrectomy as the treatment of choice, and mTOR inhibitors such as everolimus either as neoadjuvant or adjuvant targeted therapy can lead to a better clinical outcome. NGS to explore the mTOR signaling pathway may help us to better understand the pathogenesis and progression of EAML.