Masayuki Ohue

High Incidence of Thrombosis of the Portal Venous System After Laparoscopic Splenectomy: A Prospective Study With Contrast-Enhanced CT Scan

Objective:The aims of this prospective study were to investigate the true incidence of portal or splenic vein thrombosis (PSVT) after elective laparoscopic splenectomy using contrast-enhanced computed tomography (CT) scan, and outcome of anticoagulant therapy for PSVT. Summary Background Data:Although rare, thrombosis of the portal venous system is considered a possible cause of death after splenectomy. The reported incidence of ultrasonographically detected PSVT after elective open splenectomy ranges from 6.3% to 10%. Methods:Twenty-two patients underwent laparoscopic splenectomy (LS group), and 21 patients underwent open splenectomy (OS group). Preoperative and postoperative helical CT with contrast were obtained in all patients, and the extent of thrombosis was investigated. Prothrombotic disorder was also determined. Results:PSVT occurred in 12 (55%) patients of the LS group, but in only 4 (19%) of the OS group. The difference was significant (P = 0.03). Clinical symptoms appeared in 4 of the 12 LS patients. Thrombosis occurred in the intrahepatic portal vein (n = 9), extrahepatic portal vein (n = 2), mesenteric veins (n = 1), proximal splenic vein (n = 4), and distal splenic vein (n = 8). Prothrombotic disorder was diagnosed in 1 patient. Anticoagulant therapy was initiated once the diagnosis was established, and complete recanalization, except for distal splenic vein, was observed without any adverse event. Patients with splenomegaly were at high risk of PSVT. Conclusions:PSVT is a more frequent complication of laparoscopic splenectomy than previously reported but can be treated safely following early detection by CT with contrast.

Detection of Sentinel Node in Gastric Cancer Surgery by Indocyanine Green Fluorescence Imaging: Comparison with Infrared Imaging

BackgroundSecure methods for clinical detection of the sentinel node (SN) are in great demand to avoid unnecessary resection. This was a clinical exploration/feasibility study of a novel detection system for SN biopsy using indocyanine green (ICG) fluorescence imaging in gastric cancer surgery.MethodsSN biopsy using ICG dye was performed in three patients who had gastric cancer. ICG fluorescence images were obtained using a detection system comprising a charge-coupled device (CCD) camera with a cut filter as the detector and light emitting diodes (LED) as the light source. The nodes were also examined simultaneously by an infrared (IR) imaging videoscope.ResultsImmediately after intraoperative ICG injection, the fluorescence imaging system allowed easy visualization of the lymphatic vessels draining from the primary gastric tumor toward the lymph nodes and tracing of the moving injected dye. Some lymph vessels and nodes were hardly recognized by ICG green color or IR imaging. The ICG fluorescence system also allowed visualization of the lymph node when ICG was injected the day before surgery, similar to the radio-guided method.ConclusionsDetection of SNs in gastric cancer surgery using the ICG fluorescence imaging system is a promising novel technique and may perhaps prove useful for laparoscopic surgery.

Retaining cell–cell contact enables preparation and culture of spheroids composed of pure primary cancer cells from colorectal cancer

Primary culture of the cancer cells from patients’ tumors can provide crucial information of individual tumors, yet the technology has not been optimized until now. We developed an innovative culture method for primary colorectal cancer cells, based on the principle that cell–cell contact of cancer cells was maintained throughout the process. When tumor tissue was dissociated into cell clusters, in which cell–cell contact was retained, they rapidly formed spheroids that we termed cancer tissue-originated spheroids (CTOSs). CTOSs of colorectal cancer consisted of highly purified and viable cancer cells, and they were prepared with high efficiency. In immunodeficient mice, CTOSs formed xenograft tumors that retained the features of the parental tumors. Moreover, CTOSs were able to be cultured and expanded in vitro using a 3D culture system and stem cell culture medium. This method allowed evaluation of chemosensitivity and signal pathway activation in cancer cells from individual patients. Easy preparation and culture of pure primary cancer cells provides an innovative platform for studying cancer biology and developing personalized medicine.

Postoperative morbidity and mortality after mesorectal excision with and without lateral lymph node dissection for clinical stage II or stage III lower rectal cancer (JCOG0212): results from a multicentre, randomised controlled, non-inferiority trial

BACKGROUND Mesorectal excision is the international standard surgical procedure for lower rectal cancer. However, lateral pelvic lymph node metastasis occasionally occurs in patients with clinical stage II or stage III rectal cancer, and therefore mesorectal excision with lateral lymph node dissection is the standard procedure in Japan. We did a randomised controlled trial to confirm that the results of mesorectal excision alone are not inferior to those of mesorectal excision with lateral lymph node dissection. METHODS This study was undertaken at 33 major hospitals in Japan. Eligibility criteria included histologically proven rectal cancer of clinical stage II or stage III, with the main lesion located in the rectum with the lower margin below the peritoneal reflection, and no lateral pelvic lymph node enlargement. After surgeons had confirmed macroscopic R0 resection by mesorectal excision, patients were intraoperatively randomised to mesorectal excision alone or with lateral lymph node dissection. The groups were balanced by a minimisation method according to clinical N staging (N0 or N1, 2), sex, and institution. Allocated procedure was not masked to investigators or patients. This study is now in the follow-up stage. The primary endpoint is relapse-free survival and will be reported after the primary analysis planned for 2015. Here, we compare operation time, blood loss, postoperative morbidity (grade 3 or 4), and hospital mortality between the two groups. Analysis was by intention-to-treat. This trial is registered with ClinicalTrials.gov, number NCT00190541. FINDINGS 351 patients were randomly assigned to mesoretcal excision with lateral lymph node dissection and 350 to mesorectal excision alone, between June 11, 2003, and Aug 6, 2010. One patient in the mesorectal excision alone group underwent lateral lymph node dissection, but was analysed in their assigned group. Operation time was significantly longer in the mesorectal excision with lateral lymph node dissection group (median 360 min, IQR 296-429) than in the mesorectal excision alone group (254 min, 210-307, p<0·0001). Blood loss was significantly higher in the mesorectal excision with lateral lymph node dissection group (576 mL, IQR 352-900) than in the mesorectal excision alone group (337 mL, 170-566; p<0·0001). 26 (7%) patients in the mesorectal excision with lateral lymph node dissection group had lateral pelvic lymph node metastasis. Grade 3-4 postoperative complications occurred in 76 (22%) patients in the mesorectal excision with lateral lymph node dissection group and 56 (16%) patients in the mesorectal excision alone group. The most common grade 3 or 4 postoperative complication was anastomotic leakage (18 [6%] patients in the mesorectal excision with lateral lymph node dissection group vs 13 [5%] in the mesorectal excision alone group; p=0·46). One patient in the mesorectal excision with lateral lymph node dissection group died of anastomotic leakage followed by sepsis. INTERPRETATION Mesorectal excision with lateral lymph node dissection required a significantly longer operation time and resulted in significantly greater blood loss than mesorectal excision alone. The primary analysis will help to show whether or not mesorectal excision alone is non-inferior to mesorectal excision with lateral lymph node dissection. FUNDING National Cancer Center, Ministry of Health, Labour and Welfare of Japan.

Microsatellite instability and mutated type II transforming growth factor-β receptor gene in gliomas

Microsatellite instability has been reported in familial cancer syndrome and in various kinds of human sporadic tumors. We investigated the replication error (RER) and mutation rate of the transforming growth factor-beta type II receptor (TGF-beta RII) gene to determine the frequency of the RER+ phenotype and elucidate the relation between the mutation of the TGF-beta RII gene and RER in the tumorigenesis of glioma. We screened genomic DNA from 40 gliomas, comprised from 24 glioblastomas (GB), 11 anaplastic astrocytomas (AA) and five astrocytomas (AS) and compared the results with DNA from corresponding leukocytes. Seven of the 40 (18%) gliomas had the RER+ phenotype: five (21%) of 24 GB and two (18%) of 11 AA. In six gliomas we detected mutation of the TGF-beta RII gene. Five (71%) of seven RER+ and one (3%) of 33 RER-tumors had one A deletion in the (A)10 repeat of the TGF-beta RII gene. No mutations were detected in the (GT)3 repeat area of the TGF-beta RII gene. As the normal cells of these glioma patients had no mutations, we concluded that the mutations were somatic. We posit that the observed mutations inactivate the receptor through a frameshift mutation resulting in protein truncation. Our data suggest that the TGF-beta RII (A)10 repeat may be one area of genomic instability in the early stages of malignant glioma tumorigenesis.

Feasibility of a Lateral Region Sentinel Node Biopsy of Lower Rectal Cancer Guided by Indocyanine Green Using a Near-Infrared Camera System

A lateral pelvic lymph node dissection (LPLD) for lower rectal cancer may be beneficial for a limited number of patients. If sentinel node (SN) navigation surgery could be applied to lower rectal cancer, then unnecessary LPLDs could be avoided. The aim of this study was to investigate the feasibility of lateral region SN biopsy by means of indocyanine green (ICG) visualized with a near-infrared camera system (Photodynamic Eye, PDE). This study investigated the existence of a lateral region SN in 25 patients with lower rectal cancer. ICG was injected around the tumor, and the lateral pelvic region was observed with PDE. With PDE, the lymph nodes and lymph vessels that received ICG appeared as shining fluorescent spots and streams in the fluorescence image. This allowed the detection of not only tumor-negative SNs but also tumor-positive SNs as shining spots. The lateral SNs were detected in 6 of 6 T1 and T2 diseases and 17 of 19 T3 diseases. The lateral SNs were successfully identified in 23 (92%) of the 25 patients. The mean number of lateral SNs per patients was 2.1. Of the 23 patients, 6 patients underwent LPLD. Of the 3 patients who had a tumor-negative SN, all dissected lateral non-SNs were negative in all 3 cases. We could detect the lateral SNs, not only in T1 and T2 disease, but also in T3 disease. Although this is only a preliminary study, the detection of lateral SNs in lower rectal cancer by means of the ICG fluorescence imaging system is considered to be a promising technique that may be used for determining the indications for performing LPLD.BackgroundA lateral pelvic lymph node dissection (LPLD) for lower rectal cancer may be beneficial for a limited number of patients. If sentinel node (SN) navigation surgery could be applied to lower rectal cancer, then unnecessary LPLDs could be avoided. The aim of this study was to investigate the feasibility of lateral region SN biopsy by means of indocyanine green (ICG) visualized with a near-infrared camera system (Photodynamic Eye, PDE).MethodsThis study investigated the existence of a lateral region SN in 25 patients with lower rectal cancer. ICG was injected around the tumor, and the lateral pelvic region was observed with PDE.ResultsWith PDE, the lymph nodes and lymph vessels that received ICG appeared as shining fluorescent spots and streams in the fluorescence image. This allowed the detection of not only tumor-negative SNs but also tumor-positive SNs as shining spots. The lateral SNs were detected in 6 of 6 T1 and T2 diseases and 17 of 19 T3 diseases. The lateral SNs were successfully identified in 23 (92%) of the 25 patients. The mean number of lateral SNs per patients was 2.1. Of the 23 patients, 6 patients underwent LPLD. Of the 3 patients who had a tumor-negative SN, all dissected lateral non-SNs were negative in all 3 cases.ConclusionsWe could detect the lateral SNs, not only in T1 and T2 disease, but also in T3 disease. Although this is only a preliminary study, the detection of lateral SNs in lower rectal cancer by means of the ICG fluorescence imaging system is considered to be a promising technique that may be used for determining the indications for performing LPLD.

Comprehensive Clinico-Glycomic Study of 16 Colorectal Cancer Specimens: Elucidation of Aberrant Glycosylation and Its Mechanistic Causes in Colorectal Cancer Cells

The structures of neutral and acidic glycosphingolipids from both normal colorectal epithelial cells and colorectal cancer cells, which were highly purified with the epithelial cell marker CD326, have been analyzed. The analysis was performed on samples from 16 patients. The carbohydrate moieties from glycosphingolipids were released by endoglycoceramidase II, labeled by pyridylamination, and identified using two-dimensional mapping and mass spectrometry. The structures from normal colorectal epithelial cells are characterized by dominant expression of neutral type-1 chain oligosaccharides. Three specific alterations were observed in malignant transformation; increased ratios of type-2 oligosaccharides, increased alpha2-3 and/or alpha2-6 sialylation and increased alpha1-2 fucosylation. Although the degree of alteration varies case to case, we found that two characteristic alterations tend to be associated with clinical features. One is a shift from type-1 dominant normal colorectal epithelial cells to type-2 dominant colorectal cancer cells. This shift was found in 5 patients having hepatic metastasis. The other is specific elevation of alpha2-3 sialylation observed in 2 cases exhibiting high serum levels of CA19-9. Examination of the activities of the related glycosyltransferases revealed that while some alterations could be accounted for by changes in the activities of related glycosyltransferases others could not. Although the number of cases analyzed is small, these findings provide valuable information which will help in the elucidation of the mechanism of synthesis of aberrant glycosylation and its involvement in cancer malignancy.

Expression of Tumor Suppressor Gene p16INK4 Products in Primary Gastric Cancer

Recent studies have shown that the cyclin-dependent kinase (CDK) inhibitor p27Kip1 represents an indicator for patients’ outcome in several human malignancies including gastric cancer. However, the clinicopathologic value of another class of CDK inhibitor, p16INK4, has not been determined. In a retrospective study, we examined the expression of p16INK4 by immunohistochemical assay of 80 samples of primary gastric cancers and their adjacent nonneoplastic mucosas. Less than 10% of non-tumor gastric mucosal cells were p16INK4 positive, whereas the expression of p16INK4 in gastric cancer cells varied widely from 0 to 100% (mean, 24.5%). The expression of p16INK4 was not seen in 11.3% (9/80) of the cancer cases, but in 65% (52/80) this protein was even overexpressed when compared with the nonneoplastic mucosa. A clinicopathologic survey indicated that a low or no expression of p16INK4 was associated with poorly differentiated carcinoma (p = 0.0133), but the level of expression did not correlate with other parameters including patients’ prognosis or with the expression of the pRb protein. In an effort to explore the underlying mechanism for the p16INK4-negative cases, a prospective study was also performed on 20 cases of gastric cancer to compare the level of the p16INK4 protein with the methylation status of the p16INK4 promoter. Gastric cancer tissues with methylation expressed significantly lower levels of the p16INK4 protein (p = 0.0013) and two of them lacked p16INK4 expression altogether, whereas all the cancer tissues without methylation expressed it. These findings suggest that the p16INK4 protein may be associated with differentiation of gastric cancer tissues and that methylation of the p16INK4 promoter may, in part, account for the loss of p16INK4 expression.

Randomised phase III trial of adjuvant chemotherapy with oral uracil and tegafur plus leucovorin versus intravenous fluorouracil and levofolinate in patients with stage III colorectal cancer who have undergone Japanese D2/D3 lymph node dissection: final results of JCOG0205.

BACKGROUND NSABP C-06 demonstrated the non-inferiority of oral adjuvant uracil and tegafur plus leucovorin (UFT/LV) to weekly fluorouracil and folinate (5-FU/LV) with respect to disease-free survival (DFS) for stage II/III colon cancer. This is the first report of JCOG0205, which compared UFT/LV to standard 5-FU/levofolinate (l-LV) for stage III colorectal cancer patients who have undergone Japanese D2/D3 lymph node dissection. METHODS Patients were randomised to three courses of 5-FU/l-LV (5-FU 500 mg/m(2), l-LV 250 mg/m(2) on days 1, 8, 15, 22, 29, 36 every 8 weeks) or five courses of UFT/LV (UFT 300 mg m(-2)day(-1), LV 75 mg/day on days 1-28 every 5 weeks). The primary end-point was DFS. The sample size was 1100 determined with one-sided alpha of 0.05, power of 0.78 and non-inferiority margin of hazard ratio of 1.27. This trial is registered with UMIN-CTR (C000000193). FINDINGS Between February 2003 and November 2006, 1,101 patients (1092 eligible patients) were randomised to 5-FU/l-LV (n=550) or UFT/LV (n=551). Median age: 61 years, colon/rectum: 67%/33%, number of positive nodes ⩽3/>3: 73%/27%, stage IIIa/IIIb: 75%/25%. The hazard ratio of DFS was 1.02 (91.3% confidence interval, 0.84-1.23), demonstrating the non-inferiority of UFT/LV (P=0.0236). Five-year overall survival (87.5%) was higher than that in NSABP C-06 (69.6%). Grade 3/4 toxicities were 8.4% neutropenia in 5-FU/l-LV and 8.7% alanine aminotransferase elevation in UFT/LV, respectively. The incidences of diarrhoea (9.6% versus 8.5%) and anorexia (4.0% versus 3.7%) were similar between the two arms. No treatment-related deaths were reported. INTERPRETATION Adjuvant UFT/LV is non-inferior to standard 5-FU/l-LV with respect to DFS. UFT/LV should be an oral treatment option for patients with stage III colon cancer who have undergone Japanese D2/D3 lymph node dissection.

Molecular characteristics of poorly differentiated adenocarcinoma and signet-ring-cell carcinoma of colorectum

In a series of 45 poorly differentiated adenocarcinomas (por) and 7 signet‐ring‐cell carcinomas (sig) of the colorectum, K‐ras gene mutation, p53 immunostaining and microsatellite instability (MSI) were analyzed for a comparison with 46 cases of colorectal carcinomas of the well or moderately differentiated type (well/mod). In addition, the mutations of simple repeated sequences in the transforming‐growth‐factor‐β type‐II receptor (T β R‐II) gene and the BAX gene were analyzed as possible targets for DNA replication errors. Mutation of the K‐ras gene in the por, sig and well/mod specimens was detected in, respectively, 22%, 11% and 48%, positive immunostaining for p53 in 41.8%, 28.6% and 60.3%, and MSI in 36%, 30% and 4%. Frameshift mutation of the T β R‐II gene was detected in 27.5% of the por and none of the sig specimens, while corresponding figures for mutation of the BAX gene were 15.7% and 0%. Significant differences between the por and well/mod tumors were found in the occurrence of K‐ras mutation at codons 12 and 13, and MSI. Clinicopathologically, the tumor status of por with MSI was found to significantly correlate with the tumors location in the proximal colon. In cases without MSI and sig, no frameshift mutation of either the T β R‐II or the BAX gene was found. These results suggest that poorly differentiated and signet‐ring‐cell carcinomas have a genetic background different from that of well or moderately differentiated carcinomas of the colorectum, and that DNA‐replication error is at least partly involved in the carcinogenesis of these specific types of colorectal carcinomas. Int. J. Cancer (Pred. Oncol.) 84:33–38, 1999.