We performed whole transcriptome analysis of osteosarcoma bone samples. Initially, we sequenced total RNA from 36 fresh-frozen samples (18 tumoral bone samples and 18 non-tumoral paired samples) matching in pairs for each osteosarcoma patient. We also performed independent gene expression analysis of formalin-fixed paraffin-embedded samples to verify the RNAseq results. Formalin-fixed paraffin-embedded samples allowed us to analyze the effect of chemotherapy. Data were analyzed with DESeq2, edgeR and Reactome packages of R. We found 5365 genes expressed differentially between the normal bone and osteosarcoma tissues with an FDR below 0.05, of which 3399 genes were upregulated and 1966 were downregulated. Among those genes, BTNL9, MMP14, ABCA10, ACACB, COL11A1, and PKM2 were expressed differentially with the highest significance between tumor and normal bone. Functional annotation with the reactome identified significant changes in the pathways related to the extracellular matrix degradation and collagen biosynthesis. It was suggested that chemotherapy may induce the modification of ECM with important collagen biosynthesis. Taken together, our results indicate that changes in the degradation of extracellular matrix seem to be an important mechanism of osteosarcoma and efficient chemotherapy induces the genes related to bone formation. Impact statement Osteosarcoma is a rare disease but it is of interest to many scientists all over the world because the current standard treatment still has poor results. We sequenced total RNA from 36 fresh-frozen paired samples (18 tumoral bone samples and 18 non-tumoral paired samples) from osteosarcoma patients. We found that differences in the gene expressions between the normal and affected bones reflected the changes in the regulation of the degradation of collagen and extracellular matrix. We believe that these findings contribute to the understanding of OS and suggest ideas for further studies.

Osteosarcoma (OS) is a rare malignant bone tumor. It affects mostly young persons and has poor outcome with the present treatment. No improvement was observed since the introduction of chemotherapy. The better understanding of osteosarcoma development could indicate better management strategy. Repetitive DNA elements were found to play a role in cancer mechanism especially in epithelial tumors but not yet analyzed in osteosarcoma. We conducted the study to analyse the expression profile of repetitive elements (RE) in osteosarcoma.Methods: Fresh bone paired (tumor and normal bone) samples were obtained from excised parts of tumors of 18 patients with osteosarcoma. We performed sequencing of RNA extracted from 36 samples (18 tumor tissues and 18 normal bone for controls), mapped raw reads to the human genome and identified the REs. EdgeR package was used to analyse the difference in expression of REs between osteosarcoma and normal bone.Results: 82 REs were found differentially expressed (FDR < 0.05) between osteosarcoma and normal bone. Out of all significantly changed REs, 35 were upregulated and 47 were downregulated. HERVs (THE1C-int, LTR5, MER57F and MER87B) and satellite elements (HSATII, ALR-alpha) were the most significantly differential expressed elements between osteosarcoma and normal tissues. These results suggest significant impact of REs in the osteosarcoma. The role of REs should be further studied to understand the mechanism they have in the genesis of osteosarcoma.

Background The nonrecurrent laryngeal nerve (NRLN) is a rare embryologically derived variant of the RLN. We aimed to identify the proportion of NRLN (during thyroidectomy), classify clinical NRLN types, and recommend some surgical considerations. Method In this prospective study, from May 2017 to September 2018, our hospital carried out 2158 thyroid operations. We reported the NRLN rate and distinguished NRLN into four types. Results Overall, NRLN had an incidence rate of 0.74% (16 out of 2158 total thyroid surgeries). We did not detect any patient with left‐sided NRLN. The traveling patterns of the nerves could be classified as descending (12.5%), vertical (25%), ascending (37.5%), or V‐shaped (25%). Conclusion The NRLN is a rare variation of the RLN. From our experience, we recommend the guidelines will help surgeons to avoid NRLN injury.

Epidemiological characteristics of hepatocellular carcinoma (HCC) in Southern Vietnam has been well reported as in Globocan 2018 while data from the North has still not been fully presented. Therefore, we conducted this retrospective descriptive study on 198 advanced HCC patients treated at 3 major hospitals in Northern Vietnam to describe demographic features, HCC risk factors, and correlation among them in patients with advanced HCC. This information will lead to prevention efforts and provide information for allocating funds for treatment. The median age at diagnosis was 57 years (range: 19-86) and the male/female ratio was 8.9/1. The proportions of hepatitis B virus (HBV) and hepatitis C virus (HCV) infection were 81.3% and 5.6%, respectively. Hepatitis C virus infection rate was significantly higher in patients <50 years old (12.5% vs 3.3%, P = .016). There was no significant difference in age or viral hepatitis infection status by gender. Only 7.6% of patients diagnosed with advanced HCC were asymptomatic. In conclusion, with the high rate of HBV infection among patients with advanced HCC, it is necessary for increasing prevention efforts in HBV screening. Furthermore, HCV infection should be noticed in patients with advanced HCC younger than 50 years old.