BACKGROUND It remains unclear which factors,such as tumor volume and tumor invasion,influence circulating tumor DNA(ctDNA),and the origin of ctDNA in liquid biopsy is always problematic.To use liquid biopsies clinical...BACKGROUND It remains unclear which factors,such as tumor volume and tumor invasion,influence circulating tumor DNA(ctDNA),and the origin of ctDNA in liquid biopsy is always problematic.To use liquid biopsies clinically,it will be very important to address these questions.AIM To assess the origin of ctDNA,clarify the dynamics of ctDNA levels,assess ctDNA levels by using a xenograft mouse after treatment,and to determine whether tumor volume and invasion are related to ctDNA levels.METHODS Tumor xenotransplants were established by inoculating BALB/c-nu/nu mice with the TE11 cell line.Groups of mice were injected with xenografts at two or four sites and sacrificed at the appropriate time point after xenotransplantation for ctDNA analysis.Analysis of ctDNA was performed by droplet digital PCR,using the human telomerase reverse transcriptase(hTERT)gene.RESULTS Mice given two-site xenografts were sacrificed for ctDNA at week 4 and week 8.No hTERT was detected at week 4,but it was detected at week 8.However,in four-site xenograft mice,hTERT was detected both at week 4 and week 6.These experiments revealed that both tumor invasion and tumor volume were asso ciated with the detection of ctDNA.In resection experiments,hTERT was detected at resection,but had decreased by 6 h,and was no longer detected 1 and 3 d after resection.CONCLUSION We clarified the origin and dynamics of ctDNA,showing that tumor volume is an important factor.We also found that when the tumor was completely resected,ctDNA was absent after one or more days.展开更多
BACKGROUND Gastric linitis plastica(GLP)is a subset of gastric cancer with a poor prognosis.It is difficult to obtain a definitive diagnosis by endoscopic mucosal biopsies,and the usefulness of an endoscopic ultrasono...BACKGROUND Gastric linitis plastica(GLP)is a subset of gastric cancer with a poor prognosis.It is difficult to obtain a definitive diagnosis by endoscopic mucosal biopsies,and the usefulness of an endoscopic ultrasonography-guided fine-needle biopsy(EUSFNB)for GLP has been recently reported.Meanwhile,autoimmune diseases are occasionally known to coexist with malignant tumors as paraneoplastic syndrome.We herein report the usefulness of an EUS-FNB for detecting GLP and the possibility of paraneoplastic syndrome coexisting with GLP.CASE SUMMARY An 81-year-old man was admitted to our hospital for a 1-mo history of epigastric pain that increased after eating.His laboratory data revealed high levels of serum carbohydrate antigen 19-9 and immunoglobulin-G4.Endoscopic examinations showed giant gastric folds and reddish mucosa;however,no epithelial changes were observed.The gastric lumen was not distensible by air inflation,suggesting GLP.Computed tomography showed the thickened gastric wall,the diffuse enlargement of the pancreas,and the peripancreatic rim,which suggested autoimmune pancreatitis(AIP)coexisting with GLP.Because the pathological findings of the endoscopic biopsy showed no malignancy,he underwent an EUSFNB and was diagnosed with GLP.He received chemotherapy for unresectable gastric cancer due to peritoneal metastasis,after which both the gastric wall thickening and diffuse enlargement of the pancreas were improved.CONCLUSION An EUS-FNB for GLP with a negative endoscopic biopsy is useful,and AIP may develop as a paraneoplastic syndrome.展开更多
文摘BACKGROUND It remains unclear which factors,such as tumor volume and tumor invasion,influence circulating tumor DNA(ctDNA),and the origin of ctDNA in liquid biopsy is always problematic.To use liquid biopsies clinically,it will be very important to address these questions.AIM To assess the origin of ctDNA,clarify the dynamics of ctDNA levels,assess ctDNA levels by using a xenograft mouse after treatment,and to determine whether tumor volume and invasion are related to ctDNA levels.METHODS Tumor xenotransplants were established by inoculating BALB/c-nu/nu mice with the TE11 cell line.Groups of mice were injected with xenografts at two or four sites and sacrificed at the appropriate time point after xenotransplantation for ctDNA analysis.Analysis of ctDNA was performed by droplet digital PCR,using the human telomerase reverse transcriptase(hTERT)gene.RESULTS Mice given two-site xenografts were sacrificed for ctDNA at week 4 and week 8.No hTERT was detected at week 4,but it was detected at week 8.However,in four-site xenograft mice,hTERT was detected both at week 4 and week 6.These experiments revealed that both tumor invasion and tumor volume were asso ciated with the detection of ctDNA.In resection experiments,hTERT was detected at resection,but had decreased by 6 h,and was no longer detected 1 and 3 d after resection.CONCLUSION We clarified the origin and dynamics of ctDNA,showing that tumor volume is an important factor.We also found that when the tumor was completely resected,ctDNA was absent after one or more days.
文摘BACKGROUND Gastric linitis plastica(GLP)is a subset of gastric cancer with a poor prognosis.It is difficult to obtain a definitive diagnosis by endoscopic mucosal biopsies,and the usefulness of an endoscopic ultrasonography-guided fine-needle biopsy(EUSFNB)for GLP has been recently reported.Meanwhile,autoimmune diseases are occasionally known to coexist with malignant tumors as paraneoplastic syndrome.We herein report the usefulness of an EUS-FNB for detecting GLP and the possibility of paraneoplastic syndrome coexisting with GLP.CASE SUMMARY An 81-year-old man was admitted to our hospital for a 1-mo history of epigastric pain that increased after eating.His laboratory data revealed high levels of serum carbohydrate antigen 19-9 and immunoglobulin-G4.Endoscopic examinations showed giant gastric folds and reddish mucosa;however,no epithelial changes were observed.The gastric lumen was not distensible by air inflation,suggesting GLP.Computed tomography showed the thickened gastric wall,the diffuse enlargement of the pancreas,and the peripancreatic rim,which suggested autoimmune pancreatitis(AIP)coexisting with GLP.Because the pathological findings of the endoscopic biopsy showed no malignancy,he underwent an EUSFNB and was diagnosed with GLP.He received chemotherapy for unresectable gastric cancer due to peritoneal metastasis,after which both the gastric wall thickening and diffuse enlargement of the pancreas were improved.CONCLUSION An EUS-FNB for GLP with a negative endoscopic biopsy is useful,and AIP may develop as a paraneoplastic syndrome.
