Retrograde Lymphatic Spread of Esophageal Cancer: A Case Report.

The concept of the retrograde lymphatic spread of cancer cells appears to account for a subset of the essential mechanisms of cancer metastasis in various organs. However, no adequate data currently exist to illustrate the pathology of the retrograde lymphatic metastasis of cancer cells in human bodies. To shed light on this phenomenon, we report a case of a 63-year-old Japanese man who underwent an esophagectomy and lymph node dissection for early-stage esophageal cancer.The patient's clinical information was evaluated by board-certified surgeons and internists. Surgically excised materials were histopathologically evaluated by attending pathologists.Postoperative pathological examination revealed that the patient's tumor was a well-differentiated squamous cell carcinoma with negative surgical margins (T1N0M0, stage I). Apart from the primary lesion, a single lymphatic vessel invasion was found between the lamina propria and lamina muscularis of the esophagus where intralymphatic cancer cells had spread against the direction of backflow prevention valves and skipped beyond these valves without destroying them.The present case demonstrated that the retrograde lymphatic spread of cancer cells can occur in valve-equipped lymphatic vessels. Our study may not only provide a scientific basis for the concept of retrograde lymphatic metastasis but also explain a portion of the complexities associated with the lymphogenous metastasis of esophageal cancer.

Comparison of hemostasis using bipolar hemostatic forceps with hemostasis by endoscopic hemoclipping for nonvariceal upper gastrointestinal bleeding in a prospective non-randomized trial.

BACKGROUND: We previously reported on the safety and efficacy of bipolar hemostatic forceps for treating nonvariceal upper gastrointestinal (UGI) bleeding. However, no prospective or randomized studies have evaluated the efficacy of bipolar hemostatic forceps. The aim of this study was to evaluate the hemostatic efficacy of using bipolar hemostatic forceps compared with the hemostatic efficacy of the commonly used method of endoscopic hemoclipping for treating nonvariceal UGI bleeding. METHODS: A total of 50 patients who required endoscopic hemostasis for UGI bleeding were divided into two groups: those who underwent endoscopic hemostasis using bipolar hemostatic forceps (Group I) and those who underwent endoscopic hemostasis by endoscopic hemoclipping (Group II). We compared the two groups in terms of hemostasis success rate and time required to achieve hemostasis and stop recurrent bleeding. RESULTS: All (100 %) of 27 patients in Group I and 18 (78.2 %) of 23 patients in Group II were successfully treated using bipolar hemostatic forceps or by endoscopic hemoclipping alone, respectively, indicating a significantly higher success rate for Group I than for Group II (p < 0.05). The time required to achieve hemostasis was 6.8 ± 13.4 min for Group I and 15.4 ± 17.0 min for Group II. One patient in Group I (3.7 %) and four patients in Group II (22.2 %) experienced recurrent bleeding. CONCLUSION: Bipolar hemostatic forceps was more effective than endoscopic hemoclipping for treating nonvariceal UGI bleeding.

Mucosal cutting biopsy technique for histological diagnosis of suspected gastrointestinal stromal tumors of the stomach.

BACKGROUND AND AIM: The Japanese Gastrointestinal Stromal Tumor (GIST) therapeutic guidelines recommend endoscopic ultrasound-guided fine-needle aspiration biopsy for histological diagnosis. However, before 2010, this technique was only carried out at a minority of medical institutions in Japan. In the present study, we investigated the usefulness of mucosal cutting biopsy. METHODS: In 18 asymptomatic gastric submucosal tumors, mucosal cutting biopsies were carried out. We examined tumor size, tumor site (lower third: L; middle third: M; upper third: U), histopathological diagnostic yield and complications. In cases that proceeded to surgical resection with a diagnosis of GIST, we compared the pre- and postoperative histopathological diagnosis, and the histological degrees of malignancy. RESULTS: The tumors had a mean size of 20.3 mm and were located at the L site in five cases, M in four, and U in nine. Histological diagnosis of submucosal tumor was obtained in all the cases. (GIST, n = 13; heterotopic pancreas, n = 2; and leiomyoma, n = 3). No complications (e.g. bleeding, perforation or peritonitis) were seen after this procedure. In all 11 patients with GIST who underwent surgical resection, the histopathological findings from the mucosal cutting biopsy specimens were similar to those from the surgically resected specimens, with agreement between the immunostaining findings and the histological degree of malignancy (90.9%) in 10 patients. CONCLUSIONS: The mucosal cutting biopsy technique is a useful diagnostic modality for the diagnosis of gastric GIST and for selection of the appropriate treatment.

[A case of pseudomembranous colitis concomitant with toxic megacolon and paralytic ileus].

A 60-year-old man was diagnosed as pseudomembranous colitis with chief complaint of fever and abdominal distension after a cerebral operation. It was ineffective although vancomycin hydrochloride (VCM) was given orally. Complications occurred. The patient had toxic megacolon and paralytic ileus. VCM was administrated via an ileus tube. In addition, the bowel was lavaged and VCM was sprayed by colonoscopy. This therapy was very effective. Generally, a patient with pseudomembranous colitis concomitant with toxic megacolon or/and paralytic ileus is considered to have a poor prognosis, however, he completely recovered by a combination of medical treatment.

Assessment of the validity of the clinical pathway for colon endoscopic submucosal dissection.

AIM: To determine the effective hospitalization period as the clinical pathway to prepare patients for endoscopic submucosal dissection (ESD). METHODS: This is a retrospective observational study which included 189 patients consecutively treated by ESD at the National Cancer Center Hospital from May 2007 to March 2009. Patients were divided into 2 groups; patients in group A were discharged in 5 d and patients in group B included those who stayed longer than 5 d. The following data were collected for both groups: mean hospitalization period, tumor site, median tumor size, post-ESD rectal bleeding requiring urgent endoscopy, perforation during or after ESD, abdominal pain, fever above 38  °C, and blood test results positive for inflammatory markers before and after ESD. Each parameter was compared after data collection. RESULTS: A total of 83% (156/189) of all patients could be discharged from the hospital on day 3 post-ESD. Complications were observed in 12.1% (23/189) of patients. Perforation occurred in 3.7% (7/189) of patients. All the perforations occurred during the ESD procedure and they were managed with endoscopic clipping. The incidence of post-operative bleeding was 2.6% (5/189); all the cases involved rectal bleeding. We divided the subjects into 2 groups: tumor diameter ≥ 4 cm and < 4 cm; there was no significant difference between the 2 groups (P = 0.93, χ² test with Yates correction). The incidence of abdominal pain was 3.7% (7/189). All the cases occurred on the day of the procedure or the next day. The median white blood cell count was 6800 ± 2280 (cells/µL; ± SD) for group A, and 7700 ± 2775 (cells/µL; ± SD) for group B, showing a statistically significant difference (P = 0.023, t-test). The mean C-reactive protein values the day after ESD were 0.4 ± 1.3 mg/dL and 0.5 ± 1.3 mg/dL for groups A and B, respectively, with no significant difference between the 2 groups (P = 0.54, t-test). CONCLUSION: One-day admission is sufficient in the absence of complications during ESD or early post-operative bleeding.

New closure technique for large mucosal defects after endoscopic submucosal dissection of colorectal tumors (with video).

BACKGROUND: Certain large colorectal tumors satisfy expanded indications for endoscopic submucosal dissection (ESD); however, the resulting large mucosal defects may contribute to complications such as delayed bleeding and perforation. Various closure devices and methods have been developed for large mucosal defects to prevent such complications. OBJECTIVE: To demonstrate the feasibility of a new and simple technique for closing large mucosal defects after colorectal ESD. DESIGN: Pilot feasibility study. SETTING: Single center. PATIENTS: Ten patients with 10 tumors half circumferential or less in size with sufficient muscle layer exposure after ESD were selected and treated by using the closure technique between July 2009 and June 2010. INTERVENTION: Small mucosal incisions were made around the mucosal defect by the same needle-knife used during ESD. These incisions provided a better grip for conventional clips, which then facilitated lifting the surrounding mucosa across the defect without slipping, thereby making it considerably easier to reduce the size of the defect and place additional clips. MAIN OUTCOME MEASUREMENTS: Patient characteristics and tumor clinicopathologic features were assessed as well as closure completion rate, closure procedure time, and closure-related complications. RESULTS: All 10 tumors were successfully treated by ESD. Mean lesion size was 26.8 mm (range 8-50 mm). All mucosal defects were completely closed by using the new closure technique, without complications. Mean closure procedure time was 15 minutes (range 8-35 minutes). LIMITATIONS: Small sample size with specifically selected patients. CONCLUSION: Large mucosal defects resulting from colorectal ESD can be completely closed with small mucosal incisions by using conventional clips.

Time saving with narrow-band imaging for distinguishing between neoplastic and non-neoplastic small colorectal lesions.

BACKGROUND AND AIMS: For colonoscopic examinations, the narrow-band imaging (NBI) system is more convenient and timesaving than magnifying chromoendoscopy (MCE). However, the time-saving aspects of NBI techniques have not been assessed. The present study compared interpretation times between NBI and MCE techniques in distinguishing between neoplastic and non-neoplastic small colorectal lesions. METHODS: Between January and March 2010, 693 consecutive patients who underwent colonoscopy at the National Cancer Center Hospital, Tokyo, Japan, were enrolled. When the first lesion was detected by conventional white-light observation, the patient was randomly assigned to undergo a sequence of NBI and MCE observations (group A: NBI-MCE, group B: MCE-NBI). The time to diagnosis with each modality (NBI, from changing to NBI until diagnosis; MCE, from the start of indigo carmine solution spraying until diagnosis) was recorded by an independent observer. The sensitivity, specificity, and diagnostic accuracy of the first modality used in each group (NBI or MCE) were assessed by referring to the histopathological data. RESULTS: Seventy-one patients with 137 lesions were randomized to group A, and 80 patients with 163 lesions to group B. The median interpretation times were 12 s (interquartile range [IQR]: 7-19 s) in group A, and 17 s (IQR: 12-24 s) in group B, the difference being significant (P < 0.001). No significant differences were observed between NBI and MCE in terms of sensitivity, specificity, and diagnostic accuracy. CONCLUSIONS: NBI reduces the interpretation times for distinguishing between neoplastic and non-neoplastic small lesions during colonoscopies, without loss of diagnostic accuracy.

Image of tumor metastasis and inflammatory lymph node enlargement by contrast-enhanced ultrasonography.

AIM: To compare the difference between tumor-induced lymph node enlargement and inflammation-induced lymph node enlargement by contrast-enhanced ultrasonography and pathological findings. METHODS: A model of tumor-induced lymph node metastasis was prepared by embedding a VX2 tumor into the hind paws of white rabbits. A model of inflammation-induced enlargement was prepared by injecting a suspension of Escherichia coli into separate hind paws of white rabbits. Then, a solution of Sonazoid™ (GE Healthcare, Oslo, Norway) was injected subcutaneously in the proximity of the lesion followed by contrast-enhanced ultrasonography of the enlarged popliteal lymph nodes. RESULTS: In the contrast-enhanced ultrasonography of the tumor-induced metastasis model, the sentinel lymph node was imaged. An area of filling defect was observed in that enlarged lymph node. In the histology examination, the area of filling defect corresponded to the metastatic lesion of the tumor. Contrast-enhanced ultrasonography of the model on inflammation-induced lymph node enlargement, and that of the acute inflammation model performed 3-7 d later, revealed dense staining that was comparatively uniform. The pathological findings showed acute lymphadenitis mainly due to infiltration of inflammatory cells. Contrast-enhanced ultrasonography that was performed 28 d post-infection in the acute inflammation model showed speckled staining. Inflammation-induced cell infiltration and fiberization, which are findings of chronic lymphadenitis, were seen in the pathological findings. CONCLUSION: Sentinel lymph node imaging was made possible by subcutaneous injection of Sonazoid™. Contrast-enhanced ultrasonography was suggested to be useful in differentiating tumor-induced enlargement and inflammation-induced enlargement of lymph nodes.

[Recent progress in endoscopic treatment for colorectal tumors].

BACKGROUND: Endoscopic mucosal resection (EMR) is indicated for the treatment of superficial, early-stage colorectal cancer because of its minimal invasiveness and excellent results in terms of clinical outcomes. Conventional EMR techniques currently used for the resection of laterally spreading tumors (LSTs), however, are inadequate for the en-bloc resection of flat lesions > or =20 mm because both incomplete removal and local recurrence have been observed and reported on occasion. Endoscopic submucosal dissection (ESD) is widespread as a minimally invasive treatment for early gastric cancer, however, it is not as widely used in the colorectum because of its technical difficulty and complication risk. INDICATIONS FOR COLORECTAL ESD: Based on clinicopathological analyses of LSTs, the indication for colorectal ESD is an LST non-granular type (LST-NG) >20 mm. LST granular type (LST-G) >30 mm or 40 mm are possible candidates for ESD because they have a higher submucosal (SM) invasion rate and are difficult to treat even by endoscopic piecemeal mucosal resection (EPMR). ESD PROCEDURES: ESD procedures were performed using a ball tip bipolar needle knife (B-knife) and an insulation-tip knife (IT knife) with carbon dioxide (CO2) insufflation. Glycerol and 0.4% hyaluronic acid were used as an SM injection solution in order to provide longer lasting SM elevation. CONCLUSION: ESD is an effective technique for treating colorectal IST-NGs>20 mm and LST-Gs>30 mm providing a higher en-bloc resection rate as well as being less invasive than surgery.

Clinical evaluation of emergency endoscopic hemostasis with bipolar forceps in non-variceal upper gastrointestinal bleeding.

The present study was designed to evaluate the usefulness and safety of bipolar hemostatic forceps, known as a less invasive and highly safe means of thermal coagulation used for hemostasis in cases of non-variceal upper gastrointestinal bleeding. This technique of bipolar forceps is simple, safe and unlikely to induce complications, and is therefore promising as a new technique of endoscopic hemostasis. The study involved 39 cases where hemostasis was attempted with bipolar forceps to deal with non-variceal upper gastrointestinal bleeding, including 28 cases of gastric ulcer, six cases of duodenal ulcer, three cases of bleeding after endoscopic submucosal dissection (ESD), one case of Mallory-Weiss syndrome and one case of postoperative bleeding from the anastomosed area. There were 34 males and five females, with a mean age of 63.6 years. Bipolar forceps were the first-line means of hemostasis in cases of oozing bleeding (venous bleeding), pulsatile or spurting bleeding (arterial bleeding) and exposed vessels without active bleeding. The primary hemostasis success rate was 92.3%, and the re-bleeding rate was 0%. In cases where the bleeding site was located along the tangential line or in cases where large respiration-caused motions hampered identification of the bleeding site, hemostasis by means of coagulation was easily effected by application of electricity while the forceps were kept open and compressed the bleeding area. In addition, there were no complications. This technique of bipolar forceps is simple, safe and unlikely to induce complications, and is therefore promising as a new technique of endoscopic hemostasis.

Quantification of hepatic parenchymal blood flow by contrast ultrasonography with flash-replenishment imaging.

Flash-replenishment (FR) utilizes destruction of microbubbles in the scan volume by high-power ultrasound and enables to observe reperfusion at a low acoustic power. In this paper, we introduced theoretic equation between probability density function (PDF) of the transit time in the scan volume and time intensity curve (TIC) measured by FR method. From the equations, it was explained that the mean transit time (MTT) through the scan volume was calculated from the plateau level and tangent of the initial slope. Animal experiments were also performed to measure TIC in the parenchymal region of the liver using FR method. From the result of the TIC, the variant of the PDF for the transit time was found to be small and the average MTT was 11.1 s. Hepatic blood flow by an ultrasonic transit time flowmeter was also measured in the same experiment, and adequate correlation was obtained from between the two methods. The results suggested that the FR method, which is a noninvasive measurement, can predict the blood flow of the liver.