Histopathology and TB-PCR kit analysis in differentiating the diagnosis of intestinal tuberculosis and Crohn’s disease

AIM: To compare the histopathologic features of intestinal tuberculosis (ITB) and Crohn’s disease (CD) and to identify whether polymerase chain reaction for Mycobacterium tuberculosis (TB-PCR) would be helpful for differential diagnosis between ITB and CD.METHODS: We selected 97 patients with established diagnoses (55 cases of ITB and 42 cases of CD) who underwent colonoscopic biopsies.Microscopic features of ITB and CD were reviewed,and eight pathologic parameters were evaluated.Nine cases of acid fast bacilli culture-positive specimens and 10 normal colonic tissue specimens were evaluated as the positive and negative control of the TB-PCR test,respectively.PCR assays were done using two commercial kits: kit <A> detected IS6110 and MPB64,and kit <B> detected IS6110 only;a manual in-house PCR method was also performed on formalin-fi xed,paraffi n-embedded colonoscopic biopsy specimens.RESULTS: Statistically significant differences were noted between ITB and CD with regard histopathologic criteria: size of granulomas (P = 0.000),giant cells (P = 0.015),caseation necrosis (P = 0.003),confluent granulomas (P = 0.001),discrete granulomas (P = 0.000),and granulomas with lymphoid cuffs (P = 0.037).However,29 cases (52.7%) of ITB showed less than fi ve kinds of pathologic parameters,resulting in confusion with CD.The sensitivities and specificities of the TB-PCR test by kit <A>,kit <B>,and the in-house PCR method were 88.9% and 100%,88.9% and 100%,and 66.7% and 100% in positive and negative controls,respectively.The PCR test done on endoscopic biopsy specimens of ITB and CD were signifi cantly different with kit <A> (P = 0.000) and kit <B> (P = 0.000).The sensitivities and specifi cities of TB-PCR were 45.5% and 88.1%,36.4% and 100%,and 5.8% and 100%,for kit <A> and kit <B> and inhouse PCR method on endoscopic biopsy specimens.Among the 29 cases of histopathologically confusing CD,10 cases assayed using kit <A> and 6 cases assayed using kit <B> were TB-PCR positive.A combination of histologic fi ndings and TB-PCR testing led to an increase of diagnostic sensitivity and the increase (from 47.3% to 58.2) was statistically signifi cant with kit <B> (P = 0.000).CONCLUSION: The TB-PCR test combined with histopathologic factors appears to be a helpful technique in formulating the differential diagnosis of ITB and CD in endoscopic biopsy samples.

Giant choledocholithiasis treated by mechanical lithotripsy using a gastric bezoar basket

Mechanical lithotripsy(ML) is usually considered as a standard treatment option for large bile duct stones.However,it is impossible to retrieve oversized stones because the conventional lithotripsy basket may not be able to grasp the stone.However,there is no established endoscopic extraction method for such giant stone removal.We describe a case of successful extraction of a 4-cm large stone using a gastric bezoar basket.A 78-year-old woman had suffered from upper abdominal pain for 20 d.Contrast-enhanced computed tomogram revealed a 4-cm single stone in the distal common bile duct(CBD).Endoscopic stone retraction was decided upon and endoscopic papillary balloon dilation was performed using a large balloon.An attempt to capture the stone using a standard lithotripsy basket failed due to the large stone size.Subsequently,we used a gastric bezoar basket to successfully capturethe stone.The stone was fragmented into small pieces and extracted.The stone was completely removed after two sessions of endoscopic retrograde cholangiopancreatography;each of which took 30 min.No complications occurred during or after the procedure.The patient was fully recovered and discharged on day 11 of hospitalization.ML using a gastric bezoar basket is a safe and effective retrieval method in select cases,and is considered as an alternative nonoperative option for the management of difficult CBD stones.

Expression of Ki-67,p53,and K-ras in chronic pancreatitis and pancreatic ductal adenocarcinoma

AIM: To examine surgical specimens of pancreas with either chronic pancreatitis or pancreatic cancer in order to study whether ductal hyperplasia and dysplasia in pancreas represent precursor lesions for pancreatic cancer.METHODS: We examined expression of Ki-67, CEA,p53, and K-ras, in the surgical specimens of pancreas with adenocarcinomas (n = 11) and chronic pancreatitis (n = 12). Cellular proliferation was assessed by Ki-67proliferation index using the proliferation marker Ki-67.In specimens with pancreas cancer, we divided pancreas epithelium into normal (n=7), ductal hyperplasia (n=3), dysplasia (n=4), and cancerous lesion (n=11) after hematoxylin and eosin staining, Ki-67, and CEA immunohistochemical staining. In cases with chronic pancreatitis, the specimen was pathologically examined as in cases with pancreas cancer, and they were also determined as normal (n=10), ductal hyperplasia (n=4), or dysplasia (n= 5). p53 and K-ras expression were also studied by immunohistochemical staining.RESULTS: In pancreatic cancer, the Ki-67 index was 3.73±3.58 in normal site, 6.62±4.39 in ductalhyperplasia, 13.47±4.02 in dysplasia and 37.03±10.05in cancer tissue, respectively. Overall, p53 was positive in normal ducts, ductal hyperplasia, dysplasia, and carcinoma cells in 0 of 14 (0%), 0 of 7 (0%), 7 of 9 (78%),and 10 of 11 (91%), respectively, and K-ras was positive in 0 of 8 (0%), 1 of 3 (33%), 4 of 6 (67%), 4 of 5 (80%),respectively.CONCLUSION: Our results favorably support the hypothesis that ductal hyperplasia and dysplasia of the pancreas might be precursor lesions for pancreas cancer.Further evaluation of oncogenes by the molecular study is needed.

Esophageal mucosal metastasis from adenocarcinoma of the distal stomach

Dissemination of gastric cancer may usually occur by direct spread through the perigastric tissues to adjacent organ, lymphatic spread, and hematogenous spread. We report a rare case of gastric cancer with mucosal metastastic lesion on the upper esophagus that was diagnosed by endoscopy and endosonography. A biopsy of the esophageal mass was performed and the pathologic findings with immunohistochemical stain for Mucin-5AC are proved to be identical to that of gastric adenocarcinoma, suggesting metastasis from main lesion of the gastric cancer. The lesion could not be explained by lymphatic or hematogenous spread,and its metastasis mechanism is considered to be different from previous studies. We suggest that the gastroesophageal reflux of cancer cells could be one of the possible metastatic pathways for metastasis of esophagus from an adenocarcinoma of the stomach.