Neoadjuvant imatinib treatment and laparoscopic anus-preserving surgery for a large gastrointestinal stromal tumor of the rectum.

BACKGROUND: Resection of a gastrointestinal stromal tumor (GIST) of the rectum can be difficult because of the particular location in the pelvis, and a large rectal GIST often requires abdominoperineal resection. Recent reports demonstrate that neoadjuvant imatinib treatment improves surgical outcomes in patients with a rectal GIST, and there are only a few reports of the effectiveness of laparoscopic surgery for a rectal GIST. CASE PRESENTATION: A 46-year-old man was found to have a rectal GIST that measured 80 mm and was located on the anterior wall of the lower rectum. After 6 months treatment with imatinib, the tumor decreased in size to 37 mm, and laparoscopic low anterior resection was performed. The patient is currently alive without any evidence of recurrence 37 months after surgery. CONCLUSIONS: Neoadjuvant imatinib should be a treatment of choice for a large rectal GIST. When marked tumor shrinkage is achieved, laparoscopic surgery may be the preferred procedure.

Laparoscopic resection of adult colon duplication causing intussusception.

Gastrointestinal duplications are uncommon congenital malformations that can occur anywhere along the gastrointestinal tract. Most cases are recognized before the age of 2 years, and those encountered in adults are rare. We describe here a case of ascending colon duplication in a 20-year-old male that caused intussusception and was treated laparoscopically. Although computed tomography revealed a cystic mass filled with stool-like material, the preoperative diagnosis was a submucosal tumor of the ascending colon. We performed a laparoscopic right colectomy, and the postoperative pathological diagnosis was duplication of the ascending colon, both cystic and tubular components. We conclude that gastrointestinal duplications, although rare, should be considered in the differential diagnosis of all abdominal and submucosal cystic lesions and that laparoscopy is a preferred approach for the surgical treatment of gastrointestinal duplications.

Transabdominal approach assisted by thoracoscopic drainage for lower esophageal perforation.

The effectiveness of use of thoracoscopy for esophageal perforation has not been fully evaluated. We herein report a case of esophageal perforation for which a transabdominal approach assisted by thoracoscopic drainage was performed.

Successful transarterial embolization for recurrent pseudoaneurysm of the right hepatic artery with acute cholecystitis.

Pseudoaneurysm of the right hepatic artery is an extremely rare complication of acute cholecystitis. We report a patient with a right hepatic artery pseudoaneurysm associated with acute cholecystitis who was treated successfully by transarterial embolization. We also review the literature on right hepatic artery pseudoaneurysm secondary to acute cholecystitis. A 50-year-old male visited Fujieda General Municipal Hospital with an episode of sudden headache. He was diagnosed with a subarachnoid hemorrhage and treated successfully by microcoil embolization on hospital day 4. On hospital day 54, he developed fever and right upper quadrant tenderness. Abdominal ultrasonography revealed acute cholecystitis, while color Doppler imaging showed a low-echogenic mass with a pulsatile wave pattern inside the gallbladder. Contrast-enhanced computed tomography (CE-CT) demonstrated a pseudoaneurysm in the gallbladder, and angiography disclosed a right hepatic artery pseudoaneurysm. Selective transarterial embolization (TAE) was then performed using a steel coil. Abdominal pain and fever continued after TAE, with CE-CT showing re-bleeding from the previous pseudoaneurysm. Selective angiography identified extravasation at the same place as the previous pseudoaneurysm from the posterior superior pancreaticoduodenal artery and the inferior pancreaticoduodenal artery via the epicholedochal arterial plexus. TAE was performed resulting in successful occlusion of the pseudoaneurysm.

[A case of diffuse peritoneal malignant mesothelioma--intraabdominal administration of cisplatin is useful for diminishing ascites].

A 59-year-old man with a history of exposure to asbestos suffered from abdominal distension and visited our hospital. Abdominal CT revealed vast ascites but there was no obvious primary lesion. Serum tumor markers and hyaluronate were within the normal range. Abdominal puncture was carried out, and cytology of ascites was negative. We suspected diffuse malignant peritoneal mesothelioma because hyaluronate in ascites rose to 10×104 ng/mL. Ga-scintigraphy and FDG-PET were negative. We performed laparoscopic observation for definite diagnosis and found fine white particles at the peritoneum. The result of biopsy was malignant mesothelioma. The patient underwent intraperitoneal administration of cisplatin and his ascites was diminished. He lived for a year with no recurrence but died 23 months after diagnosis because of progression of pleural mesothelioma and liver metastases. Relapse of ascites was not found in the entire clinical course. Cisplatin administration in the peritoneal cavity is thus very effective in preventing progression of ascites.

Identification of Cystatin SN as a novel tumor marker for colorectal cancer.

The goal of this study was to investigate Cystatin SN, a cysteine protease inhibitor, as a novel tumor marker for colorectal cancer (CRC). Gene expression profiles of mRNA from normal tissues and cancer cell lines were performed. Twenty-eight monoclonal antibodies for Cystatin SN were generated and serum Cystatin SN was quantified using ELISA in sera from 159 patients with CRC and 40 healthy controls. Cystatin SN was highly expressed in colon cancer cells. Employing a receiver-operating characteristic curve, we obtained an area under the curve of 0.708 for Cystatin SN, 0.819 for carcinoembryonic antigen (CEA) and 0.703 for carbohydrate antigen 19-9 (CA19-9). The combination assay of Cystatin SN, CEA and CA19-9 showed 62.9% sensitivity and 90.0% specificity. Especially, the sensitivity of the combination assay in stages I and II detection, in which stages curative operation would be possible, was improved over that of the assay testing only for CEA and CA19-9 (from 37.5 to 42.5% in stage I, from 49.0 to 60.8% in stage II). Furthermore, Western blot analysis revealed that Cystatin SN was increased in the urine from patients with CRC. Our results suggest the possibility of utilizing this novel tumor marker that can be tested in urine samples. These observations suggest that Cystatin SN in combination with CEA and CA19-9 is a useful tumor marker for detecting early stage CRC and that it is a unique urinary excretory protein, suggesting that Cystatin SN might be a novel candidate for use in mass screening for CRC.

[Case of indwelling catheter dislocation into the duodenum during hepatic arterial infusion chemotherapy].

A 44-year-old man underwent hepatic arterial infusion chemotherapy and systematic chemotherapy using fluorouracil (5-FU) for recurrent liver metastasis of colon cancer. He reported upper back pain 38 weeks later. Arteriography using a port system revealed a dislocated catheter tip in the second part of the duodenum. Conservative therapy using antibiotics was employed without removing the catheter tip. Various complications related to intrahepatic arterial infusion chemotherapy have been reported. Catheter chip dislocation is rare, but can sometimes become a severe complication, thereby warranting careful follow-up after hepatic arterial infusion chemotherapy.

Human homolog of NOTUM, overexpressed in hepatocellular carcinoma, is regulated transcriptionally by beta-catenin/TCF.

The Drosophila Notum gene, which is regulated by the Wingless pathway, encodes a secreted hydrolase that modifies heparan sulfate proteoglycans. In comparative analysis of the gene expression profiles in primary human hepatocellular carcinomas (HCC) and normal organs, we observed that the human ortholog of Drosophila Notum was overexpressed markedly in a subset of HCC, but expressed rarely in adult normal tissues. Immunoblotting confirmed the overexpression of NOTUM protein in 12 of 40 primary HCC cases (30%). High levels of NOTUM protein were significantly associated with intracellular (nuclear or cytoplasmic) accumulation of beta-catenin protein: all 10 HCC with high intracellular beta-catenin also had high NOTUM expression, whereas only 2 of 30 cases (6.7%) without intracellular beta-catenin had high NOTUM expression (P < 0.00001). NOTUM expression in HepG2 cells was downregulated significantly by induction of a dominant-negative mutant of TCF4, a beta-catenin partner. In vivo binding of the beta-catenin/TCF complex to the NOTUM promoter was demonstrated by chromatin immunoprecipitation in HepG2 and SW480 cells, where canonical Wnt signaling is activated constitutively. These findings provide evidence that NOTUM is a novel target of beta-catenin/TCF4 and is upregulated in Wnt/beta-catenin signaling-activated HCC.

Overexpression of MUC13 is associated with intestinal-type gastric cancer.

Mucins are secreted or transmembrane glycoproteins that are expressed mainly in the digestive tract. This family of proteins has been the focus of much gastric cancer research as some transmembrane mucins are implicated in tumorigenesis and make attractive targets for cancer diagnosis and therapeutics. Mucins have also been utilized to classify gastric cancer by differentiating between gastric and intestinal phenotypes. Here we show that transmembrane mucin MUC13 is upregulated in gastric cancer. By quantitative real-time reverse transcription-polymerase chain reaction and immunoblot analysis, overexpression of MUC13 was verified in more than half of the samples examined. In immunohistochemical analysis, MUC13 staining was observed in 74 of 114 cases of gastric cancer (64.9%), predominantly in intestinal type (P < 0.001), and in 9 of 10 cases of intestinal metaplasia, precancerous lesions of intestinal-type gastric cancer, but not observed in normal gastric mucosa. Moreover, MUC13 staining patterns characteristic of histological type were identified: staining was on the apical side of tubular glands in intestinal type and on the cytoplasm in diffuse type. These results suggest that MUC13 is a good differentiation marker for gastrointestinal mucosa and that it may have a causal role that correlates with two distinct gastric tumorigenesis pathways.

EPHA2/EFNA1 expression in human gastric cancer.

The erythropoietin-producing hepatocellular (EPH)A2 receptor, tyrosine kinase, is overexpressed and phosphorylated in several types of human tumors and has been associated with malignant transformation. A recent report, however, indicated that stimulation of the EPHA2 receptor ligand, ephrinA1 (EFNA1), inhibits the growth of EPHA2-expressing breast cancer. The authors examined the expression of EPHA2 and EFNA1 using semiquantitative reverse transcription-polymerase chain reaction (RT-PCR) in four gastric cancer cell lines and 49 primary gastric cancer samples, as well as in normal gastric tissue. EPHA2 was more highly expressed in tumor tissue than in normal tissue in 27 cases (55%). EFNA1 was overexpressed in tumor tissue in 28 cases (57%). No significant correlation was detected between the expression levels and histologic features such as tumor size, age, vessel invasion, or lymph node involvement. However, EPHA2 overexpression was more prominent in macroscopic type 3 and 4 tumors than in type 1 or 2 advanced gastric cancer. The authors observed EPHA2 expression in three of the four gastric cancer cell lines (AGS, KATO3, and MKN74) that were examined. In one cell line, TMK1, EPHA2 expression was barely detectable using northern blotting, RT-PCR, and western blotting. In contrast, EFNA1 was detected in all cell lines. In the gastric cancer cell lines that endogenously expressed EPHA2, stimulation with ephrinA1-Fc led to decreased EPHA2 protein expression and increased EPHA2 phosphorylation. Finally, the growth of EPHA2-expressing cells was inhibited by repetitive stimulation with soluble ephrinA1-Fc. Taken together, these findings suggest that EPHA2 and EFNA1 expression may influence the behavior of human gastric cancer.

Correlation of EPHA2 overexpression with high microvessel count in human primary colorectal cancer.

Evidence suggests that the erythropoietin-producing hepatocellular (EPH) receptor tyrosine kinases (RTKs) and their ephrin (EFN) ligands are involved in human carcinogenesis. Expression of two of them, EFNA1 ligand and its receptor, EPHA2, has been proposed to contribute to tumor-induced neovascularization. Colorectal cancers were examined for expressions of EPHA2 and its ligand EFNA1 by semi-quantitative RT-PCR, and double-immunostained for EPHA2 and CD34. Microvessels in the tumors were counted. Double-staining was also performed in 25 cases of adenoma with focal cancer for comparison. Trends of overexpression of both EPHA2 and EFNA1 was found in tumor tissue compared to the corresponding normal tissue in the same specimen [22/37 (59.5%) and 25/37 (67.5%), respectively; P = 0.100 for EPHA2 and P = 0.009 for EFNA1]. Overexpression of EPHA2 and EFNA1 was noted more frequently in the early stage than in the late stage [EPHA2, 15/21 (71.4%) vs. 7/16 (43.8%), P = 0.007; EFNA1, 15/21 (71.4%) vs. 10/16 (62.5%), P = 0.007]. Both EPHA2 and EFNA1 were more frequently overexpressed in smaller tumors (less than 5 cm) than in larger tumors [EPHA2, 15/21 (71.4%) vs. 7/16 (43.8%), P = 0.017; EFNA1, 16/21 (76.2%) vs. 8/16 (50%), P = 0.001]. Tumors less than 5 cm in diameter and in stages I and II were significantly more likely to overexpress EPHA2 and EFNA1 (P = 0.001 for EPHA2, P = 0.001 for EFNA1). Microvessel counts (MVCs) after immunostaining for CD34 were significantly correlated (r = 0.343, P = 0.037) with overexpression of EPHA2. EPHA2-expressing focal cancer also surrounded microvessels in adenomas with focal cancers. These findings suggest an involvement of EPHA2 in colon carcinogenesis, mainly in stages I and II, and probably through their effect on microvessel induction.