BACKGROUND Mucinous adenocarcinoma of the colorectum is a rare histological subtype characterized by an abundant mucinous component.Mucinous tumors are frequently diagnosed at an advanced stage,which indicates an aggr...BACKGROUND Mucinous adenocarcinoma of the colorectum is a rare histological subtype characterized by an abundant mucinous component.Mucinous tumors are frequently diagnosed at an advanced stage,which indicates an aggressive subtype.However,few case reports have been published,and little information is available concerning genetic alterations in mucinous adenocarcinoma.CASE SUMMARY A 76-year-old man underwent en bloc endoscopic submucosal dissection(ESD)for the management of a type 0-Is+IIa lesion.Histological examination revealed an intramucosal mucinous adenocarcinoma with signet-ring cell carcinoma and well-to-moderately differentiated tubular adenocarcinoma.Three years after the ESD,local recurrence was detected by an endoscopic examination,revealing a new 0-Is+IIa lesion with a phenotype similar to the previously resected lesion.Re-ESD was chosen for the management of the recurrent tumor,and the histological examination showed positive tumor infiltration at the vertical margin.Additional surgical resection was performed for the curative treatment.Genetic analysis showed pathogenic alterations in RNF43 and TP53 in the adenoma and an additional SMAD4 alteration in the carcinoma.CONCLUSION This mucinous mucosal adenocarcinoma case was suggested to have an aggressive phenotype and a careful and close follow-up are required.展开更多
BACKGROUND Epstein-Barr virus(EBV)-associated carcinoma is a gastric cancer subtype with a morphology characterized by gastric carcinoma with lymphoid stroma(GCLS).Clinicopathological studies have indicated a better p...BACKGROUND Epstein-Barr virus(EBV)-associated carcinoma is a gastric cancer subtype with a morphology characterized by gastric carcinoma with lymphoid stroma(GCLS).Clinicopathological studies have indicated a better prognosis for GCLS than for common gastric carcinomas.Some previous cases of early gastric cancer associated with EBV had been diagnosed by endoscopic resection.CASE SUMMARY We present two GCLS cases subjected to endoscopic submucosal dissection(ESD)for a definitive diagnosis.A protruded gastric lesion was identified by routine endoscopic examination,but forceps biopsy showed no atypical cells before ESD.The resected specimen showed a poorly differentiated adenocarcinoma with lymphoid cells involving the mucosa and submucosa.The final diagnosis was submucosa-invasive poorly differentiated gastric adenocarcinoma.Accordingly,additional gastrectomy was recommended to obtain a complete cure.One patient underwent additional distal gastrectomy with lymph node dissection,but the other was refused because of cardiovascular complications.Both patients remained in remission for more than half a year.EBV positivity was determined by EBV-encoded RNA in situ hybridization.We also conducted a literature review of cases of early gastric cancer associated with EBV that had been diagnosed by ESD.CONCLUSION Submucosa-invasive GCLS could be dissected using ESD,and EBV positivity should be subsequently assessed to determine whether or not any additional curative surgery is required.Further prospective investigations on the prevalence of lymph node metastasis in EBV-associated carcinoma should be performed to expand the indications for endoscopic resection.展开更多
Anti-microbial peptides are essential for the intestinal innate immunity that protects the intestinal epithelia from attacks by foreign pathogens. Human β-defensin (HBD) is one of the pivotal anti-microbial peptides ...Anti-microbial peptides are essential for the intestinal innate immunity that protects the intestinal epithelia from attacks by foreign pathogens. Human β-defensin (HBD) is one of the pivotal anti-microbial peptides that are expressed in the colonic epithelia. This study investigated the effect and the signaling mechanism of inducible β-defensin HBD2 by an essential amino acid, isoleucine (Ile) in colonic epithelial cells. Here we examined the expression level of HBD2 on induction of Ile in epithelial cells, and checked this pathway. HBD2 mRNA was induced by co-incubation with IL-1α and Ile in Caco2 cells, but not by Ile alone. An inhibitor of either ERK or Gi, a subunit of G-proteins, reduced the induction of HBD2 mRNA by Ile. The treatment with Ile also increased the intracellular calcium ion concentration, thus suggesting that the GPCR and ERK signaling pathway mediate the effects of Ile. These results indicate that an essential amino acid, Ile, enhances the expression of an inducible β-defensin, namely HBD2, by IL-1α through the activation of GPCRs and ERK signaling pathway. The administration of Ile may therefore represent a possible option to safely treat intestinal inflammation.展开更多
BACKGROUND Fecal impaction is defined as a large mass of compacted feces in the colon and has the potential to induce a serious medical condition in elderly individuals.Fecal impaction is generally preventable,and ear...BACKGROUND Fecal impaction is defined as a large mass of compacted feces in the colon and has the potential to induce a serious medical condition in elderly individuals.Fecal impaction is generally preventable,and early recognition of the typical radiological findings is important for making an early diagnosis.The factors that lead to fecal impaction are usually similar to those causing constipation.Few cases with fecal impaction associated with a diverticulum have been reported.CASE SUMMARY We present the case of a 62-year-old woman who suffered from abdominal pain and vomiting,had a medical history of repeated acute abdomen and was diagnosed with fecal impaction in the descending colon based on X-ray and computed tomography(CT)imaging.After examination by gastrografinenhanced colonography following colonoscopy and CT colonography,the fecalith was suspected to have been produced at the site of a large diverticulum in the transverse colon.The fecalith was surgically resected,and a histological diagnosis of pseudodiverticulum was made.There was no recurrence during 33 mo of follow-up.CONCLUSION This case highlights the importance of accurate identification and treatment of a fecal impaction.This case indicated that the endoscopic evacuation and subsequent colonography were effective for identifying a diverticulum that might have caused fecal impaction.A fecal impaction was associated with the diverticulum.Consequently,the planned diverticulectomy was performed.Appropriate emergency medical treatment and maintenance treatments should be selected in such cases to prevent recurrence.展开更多
文摘BACKGROUND Mucinous adenocarcinoma of the colorectum is a rare histological subtype characterized by an abundant mucinous component.Mucinous tumors are frequently diagnosed at an advanced stage,which indicates an aggressive subtype.However,few case reports have been published,and little information is available concerning genetic alterations in mucinous adenocarcinoma.CASE SUMMARY A 76-year-old man underwent en bloc endoscopic submucosal dissection(ESD)for the management of a type 0-Is+IIa lesion.Histological examination revealed an intramucosal mucinous adenocarcinoma with signet-ring cell carcinoma and well-to-moderately differentiated tubular adenocarcinoma.Three years after the ESD,local recurrence was detected by an endoscopic examination,revealing a new 0-Is+IIa lesion with a phenotype similar to the previously resected lesion.Re-ESD was chosen for the management of the recurrent tumor,and the histological examination showed positive tumor infiltration at the vertical margin.Additional surgical resection was performed for the curative treatment.Genetic analysis showed pathogenic alterations in RNF43 and TP53 in the adenoma and an additional SMAD4 alteration in the carcinoma.CONCLUSION This mucinous mucosal adenocarcinoma case was suggested to have an aggressive phenotype and a careful and close follow-up are required.
文摘BACKGROUND Epstein-Barr virus(EBV)-associated carcinoma is a gastric cancer subtype with a morphology characterized by gastric carcinoma with lymphoid stroma(GCLS).Clinicopathological studies have indicated a better prognosis for GCLS than for common gastric carcinomas.Some previous cases of early gastric cancer associated with EBV had been diagnosed by endoscopic resection.CASE SUMMARY We present two GCLS cases subjected to endoscopic submucosal dissection(ESD)for a definitive diagnosis.A protruded gastric lesion was identified by routine endoscopic examination,but forceps biopsy showed no atypical cells before ESD.The resected specimen showed a poorly differentiated adenocarcinoma with lymphoid cells involving the mucosa and submucosa.The final diagnosis was submucosa-invasive poorly differentiated gastric adenocarcinoma.Accordingly,additional gastrectomy was recommended to obtain a complete cure.One patient underwent additional distal gastrectomy with lymph node dissection,but the other was refused because of cardiovascular complications.Both patients remained in remission for more than half a year.EBV positivity was determined by EBV-encoded RNA in situ hybridization.We also conducted a literature review of cases of early gastric cancer associated with EBV that had been diagnosed by ESD.CONCLUSION Submucosa-invasive GCLS could be dissected using ESD,and EBV positivity should be subsequently assessed to determine whether or not any additional curative surgery is required.Further prospective investigations on the prevalence of lymph node metastasis in EBV-associated carcinoma should be performed to expand the indications for endoscopic resection.
文摘Anti-microbial peptides are essential for the intestinal innate immunity that protects the intestinal epithelia from attacks by foreign pathogens. Human β-defensin (HBD) is one of the pivotal anti-microbial peptides that are expressed in the colonic epithelia. This study investigated the effect and the signaling mechanism of inducible β-defensin HBD2 by an essential amino acid, isoleucine (Ile) in colonic epithelial cells. Here we examined the expression level of HBD2 on induction of Ile in epithelial cells, and checked this pathway. HBD2 mRNA was induced by co-incubation with IL-1α and Ile in Caco2 cells, but not by Ile alone. An inhibitor of either ERK or Gi, a subunit of G-proteins, reduced the induction of HBD2 mRNA by Ile. The treatment with Ile also increased the intracellular calcium ion concentration, thus suggesting that the GPCR and ERK signaling pathway mediate the effects of Ile. These results indicate that an essential amino acid, Ile, enhances the expression of an inducible β-defensin, namely HBD2, by IL-1α through the activation of GPCRs and ERK signaling pathway. The administration of Ile may therefore represent a possible option to safely treat intestinal inflammation.
文摘BACKGROUND Fecal impaction is defined as a large mass of compacted feces in the colon and has the potential to induce a serious medical condition in elderly individuals.Fecal impaction is generally preventable,and early recognition of the typical radiological findings is important for making an early diagnosis.The factors that lead to fecal impaction are usually similar to those causing constipation.Few cases with fecal impaction associated with a diverticulum have been reported.CASE SUMMARY We present the case of a 62-year-old woman who suffered from abdominal pain and vomiting,had a medical history of repeated acute abdomen and was diagnosed with fecal impaction in the descending colon based on X-ray and computed tomography(CT)imaging.After examination by gastrografinenhanced colonography following colonoscopy and CT colonography,the fecalith was suspected to have been produced at the site of a large diverticulum in the transverse colon.The fecalith was surgically resected,and a histological diagnosis of pseudodiverticulum was made.There was no recurrence during 33 mo of follow-up.CONCLUSION This case highlights the importance of accurate identification and treatment of a fecal impaction.This case indicated that the endoscopic evacuation and subsequent colonography were effective for identifying a diverticulum that might have caused fecal impaction.A fecal impaction was associated with the diverticulum.Consequently,the planned diverticulectomy was performed.Appropriate emergency medical treatment and maintenance treatments should be selected in such cases to prevent recurrence.
