Congenital myopathies: characteristic and subtypes in Hong Kong

This journal suppl. entitled: 20th International Congress of The World Muscle SocietyCongenital myopathies are a group of childhood onset neuromuscular disorder with the diagnosis mainly based on genetic and pathological features. This is a unique group with phenotypic, genotypic and pathological heterogeneity, so the confirmation of an underlying diagnosis is often challenging. This is the first congenital myopathy case series in Hong Kong. A total of 15 patients have been diagnosed to have congenital myopathies with 11 patients had the genetic mutations being identified (4 patients had RYR1 mutations, 3 patients had ACTA1 mutations, 2 patients had KLHL40 mutations, 1 patient had MTM1 mutation and 1 patient had DNM2 mutation).postprin

Endometriosis-associated serous borderline tumor and endometrial stromal sarcoma of the Ovary: A report of a rare lesion in an infant

Endometriosis in infancy is most unusual, and associated tumors in this age group are exceptionally rare. We report a case of a serous borderline tumor and endometrial stromal sarcoma arising in an ovarian endometriotic cyst. The patient was an infant of 18 months of age who presented with an incidental abdominal mass. The serum sex hormones were at prepubertal levels. There was no evidence of precocious puberty or any obvious genital anomaly. Intraoperative findings included a solitary solid and multicystic right ovarian mass without evidence of any extraovarian disease. On microscopic examination, the tumor was composed of an intimate mixture of florid papillary and stromal cell proliferation in the wall of an endometriotic cyst. The papillae showed hierarchical branching and had hyalinized and edematous cores with scattered psammoma bodies. The epithelial cells were mildly atypical and mitotically inactive. The underlying endometrial stromal cells were arranged in irregular tongues that permeated the thickened fibrous cyst wall. They were mitotically active and immunoreactive for CD10. There was no evidence of any primitive germ cell tumor. The patient received no adjuvant treatment and had an uneventful postoperative follow-up period of 30 months. To the best of our knowledge, endometriosis associated with this most unusual combination of ovarian tumors has never been reported in an infant. © 2012 International Society of Gynecological Pathologists.link_to_subscribed_fulltex

Treatment of Gastric Metaplasia or Dysplasia by Endoscopic Radiofrequency Ablation: A Pilot Study

BACKGROUND/AIMS: Patients with gastric intestinal metaplasia and dysplasia are at increased risk of gastric cancer development. We tested the feasibility of using endoscopic radiofrequency ablation for the treatment of dysplasia and metaplasia in the stomach. METHODOLOGY: Patients who had histologically confirmed low-grade gastric dysplasia or IM were recruited. Endoscopic RFA was performed at 8 week-intervals for a maximum of 3 sessions. All patients were followed up by endoscopy until 12 months post-RFA. The primary outcome was the complete eradication of dysplasia or IM on follow-up. Secondary outcome was adverse events related to RFA. RESULTS: A total of 12 patients were recruited. Four patients had low-grade dysplasia and the remaining 8 patients had non-dysplastic IM at baseline. At one year after RFA, complete eradication of dysplasia was noted in four patients with low-grade dysplasia (100%). Gastric IM persisted in all patients with baseline metaplasia but the severity of IM improved in 6 (75%) patients. Endoscopic RFA was safe with minimal complications encountered. CONCLUSIONS: RFA successfully eradicated low-grade dysplasia of the stomach. Gastric IM however persisted after RFA but most patients had evidence of histological improvement on follow up. TRIAL REGISTRATION: ClinicalTrials.gov NCT01614418

RNF43 germline and somatic mutation in serrated neoplasia pathway and its association with BRAF mutation

OBJECTIVE: Serrated polyps (hyperplastic polyps, sessile or traditional serrated adenomas), which can arise in a sporadic or polyposis setting, predispose to colorectal cancer (CRC), especially those with microsatellite instability (MSI) due to MLH1 promoter methylation (MLH1me+). We investigate genetic alterations in the serrated polyposis pathway. DESIGN: We used a combination of exome sequencing and target gene Sanger sequencing to study serrated polyposis families, sporadic serrated polyps and CRCs, with validation by analysis of The Cancer Genome Atlas (TCGA) cohort, followed by organoid-based functional studies. RESULTS: In one out of four serrated polyposis families, we identified a germline RNF43 mutation that displayed autosomal dominant cosegregation with the serrated polyposis phenotype, along with second-hit inactivation through loss of heterozygosity or somatic mutations in all serrated polyps (16), adenomas (5) and cancer (1) examined, as well as coincidental BRAF mutation in 62.5% of the serrated polyps. Concurrently, somatic RNF43 mutations were identified in 34% of sporadic sessile/traditional serrated adenomas, but 0% of hyperplastic polyps (p=0.013). Lastly, in MSI CRCs, we found significantly more frequent RNF43 mutations in the MLH1me+ (85%) versus MLH1me- (33.3%) group (p<0.001). These findings were validated in the TCGA MSI CRCs (p=0.005), which further delineated a significant differential involvement of three Wnt pathway genes between these two groups (RNF43 in MLH1me+; APC and CTNNB1 in MLH1me-); and identified significant co-occurrence of BRAF and RNF43 mutations in the MSI (p<0.001), microsatellite stable (MSS) (p=0.002) and MLH1me+ MSI CRCs (p=0.042). Functionally, organoid culture of serrated adenoma or mouse colon with CRISPR-induced RNF43 mutations had reduced dependency on R-spondin1. CONCLUSIONS: These results illustrate the importance of RNF43, along with BRAF mutation in the serrated neoplasia pathway (both the sporadic and familial forms), inform genetic diagnosis protocol and raise therapeutic opportunities through Wnt inhibition in different stages of evolution of serrated polyps

Congenital Myopathies are a Group of Phenotypically and Genetically Heterogeneous Diseases

Free Paper Presentation -FP1Congenital myopathies are a group of childhood-onset neuromuscular disorder diagnosed by specific clinical, pathological, and genetic features. With the phenotypic, genotypic, and pathological heterogeneity of these specific conditions, diagnostic confirmation is often challenging. Among our 16 patients with the pathological findings of congenital myopathies, 11 have confirmed genetic mutations. Four patients have RYR1 mutations, three patients have ACTA1 mutations, two patients have KLHL40 mutations, one patient has MTM1 mutation, and one patient has DNM2 mutation. Genetically heterogeneity is well illustrated in the five patients with nemaline myopathy having different mutations including RYR1 (1 patient), ACTA1 (2 patients), and KLHL40 (2 patients). Pathological heterogeneity is nicely demonstrated in the four patients with confirmed RYR1 mutations but having different pathological features including nemaline rods, central cores, multi-minicores or type 1 fibre predominance. The specific finding of rectus femoris sparing on muscle magnetic resonance imaging provides helpful clues to the underlying RYR1 mutations. Neonatal onset of severe weakness requiring early ventilation is common in our cohort in patients with ACTA1 autosomal dominant mutation, KLHL40 autosomal recessive mutation, DNM2 autosomal dominant mutation, and MTM1 X-linked mutation. The missense RYR1 mutation (c.3523G>A) was found in two patients, and the missense KLHL40 mutation (c.1516A>C) was found in another two patients, suggesting that these variants could probably be the hot spots mutations among Chinese patients