A new technique for endoscopic submucosal dissection for early gastric cancer using an external grasping forceps.

BACKGROUND AND STUDY AIMS: Endoscopic submucosal dissection (ESD) for early gastric cancer (EGC) has improved the success rate of en-bloc resection. We report here on a new technique using an external grasping forceps. PATIENTS AND METHODS: A total of 25 patients with suitable EGCs over 10 mm in diameter located in the gastric body were enrolled. After submucosal injection followed by circumcision of the lesion with a needle-knife, an external grasping forceps was introduced with the help of a second grasping forceps and anchored at the distal margin of the lesion. With gentle oral traction applied with this forceps, the lesion was dissected endoscopically in retroversion from the aboral side. RESULTS: The mean lesion size was 15.0 mm (range 10 - 25 mm). Using the technique described, all lesions could be resected en bloc with free margins. The mean procedure time was 45 min (range 30 - 80 minutes). No significant bleeding requiring blood transfusion or perforation occurred. CONCLUSIONS: This technical modification may simplify and shorten the gastric ESD procedure, except for lesions in distal locations, without compromising the efficacy.

Anti-tumour effects of nobiletin, a citrus flavonoid, on gastric cancer include: antiproliferative effects, induction of apoptosis and cell cycle deregulation.

AIM: To demonstrate the antitumour effects of nobiletin (5,6,7,8,3',4'-hexamethoxyflavone), a citrus flavonoid extracted from Citrus depressa Hayata, on human gastric cancer cell lines TMK-1, MKN-45, MKN-74 and KATO-III. MATERIALS AND METHODS: 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay, the TdT-mediated dUTP biotin nick-end labelling (TUNEL) method and cell-cycle analysis revealed that nobiletin acted on these cells in several ways, namely by direct cytotoxicity, induction of apoptosis and modulation of cell cycle. The efficacy of combined treatment of nobiletin with a conventional anticancer drug, CDDP, was also examined. Treatment with nobiletin 24 h prior to CDDP administration showed a synergistic effect compared to the control. CONCLUSIONS: Although the effective dose and administration route of nobiletin require further investigation, our study represents a potential successful linking of this compound with the treatment of gastric cancer.

The citrus flavonoid, nobiletin, inhibits peritoneal dissemination of human gastric carcinoma in SCID mice.

The flavonoid nobiletin (5,6,7,8,3',4'-hexamethoxyflavone), found in Citrus depressa Rutaceae, a popular citrus fruit in Okinawa, Japan, reportedly inhibits the production of pro-matrix metalloproteinase (proMMP)-1, 3, and 9 in rabbit synovial fibroblasts in vitro. In the present study, we demonstrated the inhibitory effects of nobiletin on the proliferation of the cancer cell line, TMK- 1, and its production of MMPs. In the SCID mouse model, we found that nobiletin inhibited the formation of peritoneal dissemination nodules from TMK-1. The enzymatic activity of MMP-9 expressed in culture medium obtained from a co-culture of TMK-1 and mouse fibroblastic cells was inhibited by nobiletin in a concentration-dependent manner. In the SCID mouse model, total weight of dissemination nodules was significantly lower in the treated group compared with the vehicle control group (0.07 g vs. 0.78 g, P = 0.0059). The total number of dissemination nodules was also significantly lower than in the vehicle control group (7.5 vs. 69.3 / body, P = 0.0001). These results suggest that nobiletin may be a candidate anti-metastatic drug for prevention of peritoneal dissemination of gastric cancer.

Docetaxel enhances the cytotoxicity of tetrahydropyranyladriamycin in a sequence-dependent manner.

BACKGROUND: Taxanes and anthracyclines are active against breast cancer. In this study we investigated the combined antitumor activity of these drugs, with particular regard to sequence-dependency. MATERIALS AND METHODS: The combined antitumor activity of docetaxel and tetrahydropyranyladriamycin (THP) against two human breast cancer xenografts was assessed using an in vitro histoculture drug-response assay. The sequence-dependency of the combined cytotoxicity was evaluated by isobologram. RESULTS: A synergistic antitumor activity of combined docetaxel + THP was exhibited against the R-27 xenograft when docetaxel was given first or simultaneously with THP. However, this synergism was diminished when THP was used before docetaxel. While an additive effect of combined docetaxel + THP was observed against MX-1 xenograft when docetaxel was given first or simultaneously with THP, this effect was not marked using the THP/docetaxel sequence. CONCLUSION: Docetaxel increased the antitumor activity of THP, but only when administered before or simultaneously with THP.

[Clinical significance of sentinel node navigation surgery in the treatment of early gastric cancer].

Radical lymphadenectomy is the standard surgical approach even for early-stage gastric cancer with a relatively low incidence of lymph node metastasis because of the limited sensitivity of diagnostic imaging to detect micrometastasis in regional lymph nodes. The sentinel node (SN) concept is one topic among novel diagnostic procedures for micrometastasis. The SN is defined as the first draining node from the primary lesion and it would be the first site of micrometastasis. SN biopsy has been clinically validated and applied for the surgical treatment of malignant melanoma and breast cancer. Although the feasibility of this technique in other solid tumors including gastric cancer is still controversial, there are several reports demonstrating the diagnostic significance of SN mapping in early gastric cancer. We have established radio-guided SN mapping for early gastric cancer, and the diagnostic accuracy using this procedure in cT1N0 cases reached 98%. The radio-guided method allows us to detect the SN in endoscopic surgery quantitatively and reproducibly. Validation of the SN concept in gastric cancer in a multi-centric clinical trial is essential for clinical application of this procedure, including the establishment of a novel, minimally invasive approach for early-stage gastric cancer.

Laparoscopic detection of sentinel lymph nodes in gastrointestinal cancer: a novel and minimally invasive approach.

Although the sentinel node (SN) concept has been validated in malignant melanoma and breast cancer, the application of this concept for other solid tumors, including gastrointestinal (GI) cancer, is still controversial. We have demonstrated the feasibility of radioguided SN mapping during laparotomy in patients with esophageal, gastric, and colorectal cancers. In 188 patients, the SNs identified by this technique had an overall diagnostic accuracy of 96% for regional lymph node metastasis. Aberrant drainage sites that have been called skip metastasis from the primary lesion were detectable using this method. More recently, we have undertaken SN mapping during laparoscopic surgery. A combination of radiotracer and blue dye optimized the identification of SNs that drained GI cancers. Our preliminary data indicate that laparoscopic mapping of the SN is a sensitive intraoperative technique for identifying lymph node micrometastasis, and we believe that it will become an important component of a minimally invasive approach to early-stage GI cancers.

UCN-01 (7-hydoxystaurosporine) inhibits in vivo growth of human cancer cells through selective perturbation of G1 phase checkpoint machinery.

Mechanisms underlying tumor sensitivity to the antitumor agent UCN-01 (7-hydroxystaurosporine) were examined in the nude mouse model using three human tumor xenografts, two pancreatic cancers (PAN-3-JCK and CRL 1420) and a breast cancer (MX-1). UCN-01 antitumor activity was evaluated in terms of relative tumor weights in treated and untreated mice bearing the tumor xenografts. The activity of cyclin-dependent kinase 2 (CDK2), levels of p21 and p27 proteins, pRb status and cell cycle were evaluated. Induction of p21 and apoptosis were also assessed immunohistochemically in CRL 1420. UCN-01 was administered intraperitoneally at a dose of either 5 or 10 mg / kg daily for 5 days followed by a further 5 injections after an interval of 2 days. UCN-01 significantly suppressed the growth of both pancreatic cancers, but was ineffective against MX-1. p21 protein expression was markedly induced in the UCN-01-sensitive pancreatic carcinoma xenografts at both doses, but p21 induction was only evident in the UCN-01-resistant MX-1 at 10 mg / kg. MX-1 exhibited CDK2 activity that was 6-fold higher than that of pancreatic cancer strains, which may explain the resistance of MX-1 to UCN-01 despite the induction of p21 at the dose of 10 mg / kg. The UCN-01-sensitive tumors exhibited G1 arrest and increased levels of apoptosis, changes not observed in resistant MX-1. In conclusion, it appears that a determining factor of in vivo UCN-01 sensitivity involves the balance of CDK2 kinase activity and p21 protein induction, resulting in augmented pRb phosphorylation, G1 cell cycle arrest and apoptosis.

UCN-01 (7-hydroxystaurosporine) enhances 5-fluorouracil cytotoxicity through down-regulation of thymidylate synthetase messenger RNA.

UCN-01 (7-hydroxystaurosporine) is a newly developed cell cycle inhibitor known to have several modes of action, including inhibition of cyclin-dependent kinase, induction of p21 and suppression of pRb phosphorylation. In order to test a combination therapy of UCN-01 and 5-fluorouracil (5-FU), growth inhibition of CRL 1420 (MIA PaCa-2; undifferentiated pancreatic carcinoma) by four different treatments was measured using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl-2H-tetrazolium bromide (MTT) assay. The treatments used were UCN-01 alone, 5-FU alone, 5-FU followed by UCN-01 (5-FU/UCN-01) and UCN-01 followed by 5-FU (UCN-01/5-FU). We also assessed changes in thymidylate synthetase (TS) mRNA levels, TS activity, and 5-FU incorporation by RNA (F-RNA) for each treatment. Although treatment with UCN-01 alone, 5-FU alone, and 5-FU/UCN-01 inhibited CRL 1420 growth in a concentration-dependent manner, treatment with UCN-01/5-FU inhibited the growth of CRL 1420 synergistically at less than 1 microg/ml drug concentration. The down-regulation of TS mRNA by UCN-01 resulted in stable total TS and decreased free TS, and UCN-01/ 5-FU resulted in enhanced thymidylate synthetase inhibition rate (TSIR) compared to UCN-01 alone and 5-FU/UCN-01. This increased TSIR due to UCN-01 pretreatment was accompanied by elevated F-RNA concentrations in the UCN-01/5-FU treatment. The suppression of TS mRNA and TS activity by UCN-01 may lead to higher sensitivity of tumor cells to 5-FU and may explain the synergistic antitumor effect of UCN-01/5-FU. In conclusion, low concentrations of UCN-01 (from 0.01 to 1 microg/ml) may be clinically useful, affording low cytotoxicity of UCN-01, while enhancing the antitumor effect of 5-FU.

[Curative laparoscopic surgery for early gastric cancer: eight years experience].

We have applied two different laparoscopic surgical techniques for early gastric cancer and have successfully treated 111 patients since March 1992. The indications are: 1) preoperative diagnosis of mucosal cancer; 2) lesion size of < 25 mm if the protruding type; and 3) lesion size < 15 mm and UI (-) if the depressed type. The first technique is laparoscopic wedge resection of the stomach using a lesion-lifting method (n = 93). The gastric wall around the cancerous lesion is exposed laparoscopically. The abdominal wall and gastric wall in the vicinity of the lesion are pierced using a 12-G sheathed needle. A small metal rod with a fine wire is introduced into the stomach through the outer sheath. By retracting the metal rod, the lesion can be lifted precisely (i.e., lesion-lifting method). Wedge resection at a sufficient distance from the metal rod is carried out using an endoscopic stapler. The second technique is referred to as laparoscopic intragastric mucosal resection (n = 18). Three balloon trocars are placed in the stomach laparoscopically. The stomach is then insufflated with CO2, and surgical instruments are introduced. The mucosal and submucosal layers around the lesion are resected with sufficient surgical margins. The selection of the laparoscopic technique depends on the site of the cancerous lesion. In our series of 111 patients, sufficient horizontal (mean 15 +/- 5 mm and 8 +/- 4 mm, respectively, using the first and second technique) and vertical surgical margins were achieved. There was no mortality and no major complications in patients undergoing either surgical technique. There have been two recurrences, both mucosal lesions found 2 years after the initial surgery, which were successfully treated with gastrectomy and laser irradiation. All patients have survived for 3 to 96 months, and there has been no trocar site recurrence. In conclusion, these laparoscopic procedures are curative and minimally invasive treatments for early gastric cancer.

[Sensitivity of UCN-01 lies in the balance of CDK 2 kinase and p21].

Five human cancer cell lines (MKN 45, HT-29, WiDr, PAN-3-JCK, and CRL 1420) were used to evaluate the antitumor spectrum of UCN-01, which suppressed the growth of these digestive cancer cell lines. A human pancreatic cancer xenograft (CRL 1420) and breast cancer xenograft (MX-1) were used to determine their sensitivity to UCN-01, in nude mice. UCN-01 significantly suppressed the tumor growth of CRL 1420 at a dose of 10 mg/kg in a schedule of (qd x 5) x 2, but was ineffective for MX-1. While p21 protein expression was induced by UCN-01 in both CRL 1420 and MX-1, an accumulation of dephosphorylated ppRb was observed only in CRL 1420, resulting in G1 block as detected by flow cytometric analysis. The CDK 2 activity of MX-1 was almost 6 times higher than that of CRL 1420, which might account for the resistance of MX-1 to UCN-01 in spite of the induction of p21 in this strain. We conclude that the determinant of sensitivity to UCN-01 lies in the balance of CDK 2 kinase activity and p21 protein induction.

Surgery for gastric carcinoma in patients more than 85 years of age.

BACKGROUND: The incidence of gastric carcinoma is increasing in elderly patients. It has not been determined whether surgery improves the quality of life or prolongs survival in patients older than 85 years. This study was designed to evaluate surgery as a treatment option in patients more than 85 years of age. METHODS: The records of 18 patients aged 85 to 91 years (mean 87.3 years), who underwent surgery for gastric carcinoma between 1983 and 1997 were analysed. RESULTS: Three patients had multiple lesions. A total of 21 lesions were examined. Operative procedures included distal gastrectomy (n = 12), total gastrectomy (n = 4), proximal gastrectomy (n = 1), and laparoscopic wedge resection (n = 1). Perigastric lymphadenectomy was performed in 15 patients. No lymph node dissection was performed in three patients. Postoperative complications, including delirium, respiratory dysfunction, cardiac dysfunction, anastomotic leakage, bleeding, and ileus, occurred in 11 patients. There were two hospital deaths in patients who underwent emergency surgery. Survival was neither shortened nor prolonged by surgery as determined by life table analysis. CONCLUSIONS: Surgical treatment should not be avoided based solely on the age of the patient, and quality of life in this population may be improved by surgery. Careful patient selection should include an assessment of the will to live.

Laparoscopic wedge resection of gastric submucosal tumors.

Minimally invasive surgery has revolutionized the treatment of gastrointestinal tumors. Submucosal tumors (SMTs) of the stomach can be resected using laparoscopic techniques. Between 1993 and 1997, laparoscopic wedge resection was performed in 34 patients with an SMT of the stomach. The tumors ranged from 8 to 60 mm in diameter. All surgical margins were clear. The average operative time was 131 minutes. Most of the patients began eating on the first postoperative day and were discharged within 5 to 7 days. Histopathologic examination of the tumors showed gastrointestinal stromal tumor (n = 14), ectopic pancreas (n = 7), leiomyosarcoma (n = 4), schwannoma (n = 3), carcinoid (n = 2), leiomyoma (n = 2), an inflammatory lesion caused by parasites (n = 1), and cyst (n = 1). No recurrences were observed over the 5-year follow-up period. A solid SMT of the stomach larger than 20 mm in diameter can be treated using laparoscopic wedge resection.

Matrix metalloproteinase expression in cultured human gastric wall fibroblasts--interactions with Helicobacter pylori isolated from patients with ulcers.

BACKGROUND: Matrix metalloproteinases (MMPs), enzymes capable of degrading collagens and other extracellular matrix components, have been implicated in gastric ulcer formation. However, the effect on MMP expression of Helicobacter pylori, also implicated in these lesions, has not been studied to our knowledge. AIM: To seek links between H. pylori and MMP expression likely to affect gastric ulcer formation. After fibroblasts from human gastric wall were cocultured with H. pylori. concentrations of MMP-1 and -2 in the medium were determined by enzyme-linked immunosorbent assays. RESULTS: Whereas MMP-1 was not detected in media from fibroblasts or H. pylori culture alone, MMP-1 was detected in cocultures (P<0.01). Similar amounts of MMP-2 were detected in medium from fibroblasts cultured alone and with H. pylori. No MMP-2 production by H. pylori cultured alone was detected. CONCLUSIONS: MMP-1 appears to be important in gastric ulcer pathogenesis, and MMP-1 induction by H. pylori may impede gastric ulcer healing.

[The validity of the sentinel node concept in gastrointestinal cancers].

Although the sentinel node concept has been validated and clinically applied to breast cancer and malignant melanoma, its clinical significance in other solid tumors has not been thoroughly investigated. With regard to gastrointestinal (GI) cancers in particular, our surgeons have been cautious because of the high frequency of skip metastasis and the complicated lymphatic system in the GI tract. We would like to emphasize that so-called skip metastasis has been defined according to anatomic classification of regional lymph nodes and that the lymphatic drainage route must be patient or lesion specific. To test the validity and feasibility of this concept in GI cancers, we have established a radio-guided intraoperative sentinel node navigation system using preoperative endoscopic submucosal injection of radioactive tracer followed by intra-operative gamma-probing. In 131 patients with GI cancers (esophagus: 22, stomach: 71, colorectum: 38), the detection rate of sentinel nades was 91% and overall diagnostic accuracy of lymph node metastasis by sentinel node status was 97%. Initial results suggest further investigation of this procedure as an accurate staging and a minimally invasive approach to early GI cancers.

Dihydropyrimidine dehydrogenase and messenger RNA levels in gastric cancer: possible predictor for sensitivity to 5-fluorouracil.

We investigated the correlation between tumor sensitivity to 5-fluorouracil (5-FU) and enzymatic activities of thymidylate synthetase (TS) and dihydropyrimidine dehydrogenase (DPD) in human gastric cancer specimens. Forty-one patients with advanced gastric cancer gave informed consent and were enrolled in the study. Biopsy specimens of gastric cancer were obtained preoperatively through gastrofiberscopy and used to determine TS and DPD messenger RNA (mRNA) levels. TS and DPD enzyme activity and mRNA levels were also measured in resected tumor tissue samples obtained after surgical resection. TS and DPD activity were measured using the TS-binding assay and a radioenzymatic assay, respectively, while mRNA levels were measured by semi-quantitative reverse transcription-polymerase chain reaction (RT-PCR), with co-amplification of glyceraldehyde-3-phosphate dehydrogenase (GAPDH) as an internal standard. 5-FU sensitivity of resected tumor specimens was measured by the tetrazolium-based colorimetric assay (MTT assay). Both TS and DPD mRNA levels correlated well between biopsied and resected tumor specimens. A statistically significant correlation was also observed between mRNA levels in biopsied specimens and enzymatic activities in resected specimens. DPD levels significantly correlated with 5-FU sensitivity, such that high DPD activity and high DPD mRNA levels resulted in low sensitivity to 5-FU. In contrast, no correlation was observed between TS activity or TS mRNA levels and 5-FU sensitivity. We conclude that tumor DPD mRNA level, as assessed from biopsy specimens obtained by gastrofiberscopy, may be a useful indicator in predicting tumor sensitivity to 5-FU in patients with gastric cancer.

Gastrointestinal stromal tumors treated by laparoscopic surgery: report of three cases.

Three cases of gastrointestinal stromal tumors (GIST) were treated by a laparoscopic wedge resection of the stomach. The tumor characteristics were confirmed to be nonepithelial, nonlymphomatous, nonmyogenic, and nonneurogenic gastrointestinal neoplasms with an uncertain origin which were CD34-positive and actin- and S-100-negative. The malignant potential was estimated based on the mitotic figures and growth rates. The results suggest that laparoscopic surgery is an adequate strategy for gastric submucosal tumors including GIST, and also indicates this technique to be a curative, safe, and minimally invasive procedure for both diagnosis and treatment.

Jejunal limb obstruction caused by a cholesterol stone 15 years after a total gastrectomy and 20 years after a cholecystectomy: report of a case.

We present herein the rare case of a 74-year-old woman found to have jejunal limb obstruction caused by a cholesterol stone 15 years after a total gastrectomy with Roux-en-Y anastomosis, and 20 years after a cholecystectomy. The patient complained of repeated episodes of upper abdominal distress on three separate occasions over a period of 20 months, and jejunal limb obstruction was diagnosed by abdominal computed tomography scanning and (99m)Tc scintigraphy. Surgery revealed a stone incarcerated in the jejunal limb, where the anastomosis had become slightly stenotic. The removed stone was 3.5 cm in diameter and was subsequently demonstrated to be a cholesterol stone by chemical analysis. This report is thought to be the first to describe jejunal limb obstruction caused by a gallstone incarcerated in the jejunal limb after a total gastrectomy in a patient with a history of cholecystectomy.

The role of the sentinel lymph node in gastrointestinal cancer.

Evaluation of the clinical significance of the sentinel node concept in GI cancer has just begun. The authors' preliminary data, using intraoperative radiation techniques and the gamma probe, suggest that it is worthwhile to continue the evaluation of this procedure to determine its role in an accurate staging and a minimally invasive approach to GI cancers.