Futoshi Miyazono

Surgical Maneuvers Enhance Molecular Detection of Circulating Tumor Cells During Gastric Cancer Surgery

ObjectiveTo evaluate the relation between the presence of cancer cells in blood according to the time course during a surgical procedure and liver metastases in patients with gastric cancer. Summary Background DataSeveral studies have reported on the detection of circulating cancer cells in blood by reverse transcriptase–polymerase chain reaction (RT-PCR). However, few reports have examined the relation between molecular detection of circulating cancer cells according to the time course during a surgical procedure and blood-borne metastases. MethodsBlood samples from 57 patients with gastric cancer were obtained from the portal vein, peripheral artery, and superior vena cava before and after tumor dissection. After total RNA was extracted from each blood sample, carcinoembryonic antigen (CEA)-specific RT-PCR was performed. ResultsCEA-mRNA was detected in the blood of 21 (36.8%) of the 57 patients. CEA-mRNA was not detected in the blood obtained from 15 healthy volunteers and 15 patients with benign disease. The positive rate increased in proportion to the depth of tumor. The incidence of positive CEA-mRNA did not differ among the various sites of blood sampling. The appearance of circulating cancer cells was related to the surgical maneuver. A significant relation was found between the detection of CEA-mRNA and blood-borne metastases. ConclusionsA high incidence of positive CEA-mRNA was found in the blood during gastric cancer surgery. Surgical maneuvers are a possible cause of hematogenous metastasis. The authors found that patients with positive CEA-mRNA had a high risk of blood-borne metastasis even after curative resection.

Mutations in the mitochondrial DNA D-Loop region occur frequently in adenocarcinoma in Barrett's esophagus

Mitochondrial DNA (mtDNA) is known for high mutation rates caused by lack of protective histones, inefficient DNA repair systems, and continuous exposure to mutagenic effects of oxygen radicals. We examined the frequency of mutations in the mtDNA D-Loop region in 20 patients with Barretts carcinoma and associated Barretts epithelium by automated DNA sequencing. Mutations were detected in eight of 20 (40%) patients in tumor and/or tumor-associated Barretts epithelium. In six of eight positive cases, the mutations were detected only in the tumor, one of eight showed mutations in tumor and Barretts epithelium, and one of eight only in Barretts epithelium. The degree of dysplasia in Barretts epithelium was classified low-grade in one and high grade in the two specimens. There was no association of mtDNA D-Loop mutations with histopathological stage of disease or tumor grading. We present the first study of frequent occurrence of mutations in the mtDNA D-Loop regions in adenocarcinomas in Barretts esophagus. Furthermore, this study supports the hypothesis that oxidative damage might be a mechanism for the induction of adenocarcinoma in Barretts esophagus. Since mutations were identified in tumor-associated dysplastic Barretts epithelium, they also might become a marker for the malignant potential of Barretts epithelium.

Molecular detection of circulating cancer cells during surgery in patients with biliary-pancreatic cancer

BACKGROUND It remains unclear whether surgical treatment for biliary-pancreatic cancers provokes the hematogenous dissemination of cancer cells. The aim of this study was to detect circulating cancer cells in the blood stream before and during tumor resection for biliary-pancreatic cancer. METHODS We analyzed blood samples obtained perioperatively from the portal vein, peripheral artery, and superior vena cava, using a carcinoembryonic antigen (CEA)-specific nested reverse transcriptase-polymerase chain reaction. RESULTS CEA-mRNA expression was detected in the blood of 21 (52.5%) of 40 patients with biliary-pancreatic cancer. The patients with detectable CEA-mRNA expression included 8 (42.1%) of 19 with bile duct cancers and 13 (61.9%) of 21 with pancreatic cancers. CEA-mRNA expression was not detected in blood obtained from 15 healthy volunteers and 15 patients with benign disease. The positive rate of CEA-mRNA of advanced clinical stage (TNM pStage III and IV) showed higher than that of early stage (pStage I and II; P <0.05). Tumor resection increased significantly the positive rates of CEA-mRNA in the blood stream of three kinds of vessel. CONCLUSIONS Surgical procedures provoke the hematogenous dissemination of cancer cells perioperatively. Therefore, new strategies during operations to prevent liver metastases are needed to improve the survival of patients with biliary-pancreatic cancer.

Evaluation of colloid size for sentinel nodes detection using radioisotope in early gastric cancer

The purpose of this study was to investigate the relationship between colloid size and the detection of sentinel nodes (SN) in early gastric cancer. Three size of 99mTechnetium-tin colloids (500, 100 and 50 nm) were preoperatively injected into the submucosa under endoscopic control. Lymph node metastasis and micrometastasis was examined. RI-uptake in the hottest nodes and the total RI-uptake in the hot nodes were highest in the size of 100 nm. At least one lymph node metastasis, including micrometastasis, was included in the hot nodes. RI-labeled colloid size was one of the important factors to detect SN in early gastric cancer.

Intraoperative molecular detection of circulating tumor cells by reverse transcription-polymerase chain reaction in patients with biliary-pancreatic cancer is associated with hematogenous metastasis

BackgroundCirculating tumor cells in the blood were frequently detected by reverse transcription-polymerase chain reaction during operation in patients with biliary-pancreatic cancer. We investigated the relationship between circulating tumor cells during operation and hematogenous metastases.MethodsBlood samples from 67 patients with biliary-pancreatic cancer were obtained from the portal vein, peripheral artery, and superior vena cava during operation. Afer total RNA was extracted from each blood sample, carcinoembryonic antigen (CEA)-specific reverse transcription-polymerase chain reaction was performed.ResultsIntraoperative CEA-messenger RNA (mRNA) expression was detected in the blood of 32 (47.8%) of 67 patients with biliary-pancreatic cancer, although it was not detected in the blood obtained from 20 healthy volunteers or 15 patients with benign disease of the biliary pancreas. The incidence (37.5%) of hematogenous metastases after surgery in the CEA-mRNA-positive group (n =32) was significantly higher than that (11.4%) in the negative group (n=35;P=.01). In stage I, II, and III patients, survival of the CEA-mRNA-positive group was significantly worse compared with that of negative group (P=.03)ConclusionsIntraoperative molecular detection of circulating tumor cells in patients with biliary-pancreatic cancer relates to a high risk of hematogeneous metastasis and is associated with unfavorable prognosis even after curative resection.

Distribution of Lymph Node Metastasis Including Micrometastasis in Gastric Cancer with Submucosal Invasion

The purpose of this retrospective study was to analyze the distribution of lymph node metastases, including micrometastases, according to the location of the gastric cancer with submucosal invasion. A total of 118 patients with submucosal gastric cancer were enrolled in this study. The distribution of lymph node metastases was examined according to tumor location. Immunohistochemical examination using anti-cytokeratin antibody was performed to examine nodal micrometastases in 118 patients. Lymph node metastasis was found in 19.5% (23/118) of the patients. Significant differences were found for tumor size and depth, lymphatic invasion, and venous invasion for patients with and without nodal metastasis. The distribution of lymph node metastasis for tumors at upper or middle portions of the stomach was mainly found along the left gastric artery. The distribution of lymph node metastasis for tumors in the lower and lesser curvature varied. Immunohistochemical analysis found that 15 of 23 patients with lymph node metastasis found by histologic examination had micrometastases. The presence of two or more lymph node micrometastases was found in these 15 patients, and they were distributed in another stations, including distant nodes. The incidence of micrometastasis was 24.2% (23/95) in pN0 patients. Lymph node micrometastases were confined to regional nodes near the primary tumor. When planning minimally invasive treatment for submucosal gastric cancer, it is important to understand the distribution of lymph node metastasis, including micrometastasis, according to tumor location.

Infiltration of antitumor immunocytes into the sentinel node in gastric cancer

The sentinel node (SN) is regarded as the first drainage lymph node, and tumor cells are considered likely to directly affect the SN. However, few reports have identified differences between SNs and non-SNs in cancer patients. Subjects in this study included 27 patients with gastric cancer who underwent curative operation and intraoperative detection of SNs by radioisotope methods. The mean number of SNs was 3.2 (range 1 to 5). Degree of infiltration of natural killer cells, dendritic cells, MIB-1 labeling index, and CD3-ξ expression of lymphocytes in SNs and non-SNs were examined by means of immunohistochemical methods. Degree of infiltration was compared according to depth of invasion and between SNs and non-SNs. Patients with early-stage cancer displayed a greater degree of infiltration of MIB-1 labeling index and CD3-ξ expression than patients with pT2 or pT3 lesions (P<0.05). The MIB-1 labeling index in SNs was significantly lower than that in non-SNs (P<0.05). However, no significant difference was observed in infiltration of natural killer cells, dendritic cells, or CD3-ξ. Morphologic changes of dendritic cells in SNs were not definite. Our results suggest that SNs in gastric cancer might not be suppressed, unlike in breast cancer and melanoma. SN paralysis may depend on tumor- and organ-specific characteristics or exogenous stimulation from the gastric mucosa. Studies in progress will help to identify immunologic paralysis of the SN in various types of cancer. Attention must therefore be paid to organ specificity.

Paraaortic lymph node micrometastasis and tumor cell microinvolvement in advanced gastric carcinoma.

Abstract:Background. Paraaortic lymph node dissection in advanced gastric carcinoma is controversial. The purpose of this study was to investigate the incidence and significance of micrometastasis (MM) or tumor cell microinvolvement (TCM) in these critical lymph nodes.Methods. A total of 2339 lymph nodes, including 390 paraaortic nodes, obtained from 47 patients with advanced gastric carcinoma were examined immunohistochemically, using cytokeratin antibody.Results. Lymph node metastasis was found in 95 of the 390 paraaortic nodes of 14 patients by routine histological examination. MM or TCM was immunohistochemically detected in 45 of the 295 negative paraaortic lymph nodes from 15 of 33 patients (MM, n = 5; TCM, n = 10). The 5-year-survival rate in the paraaortic node-negative group and cytokeratin-positive group was significantly higher that that of the hematoxilin and eosin-positive group. The total number of lymph node metastases by hematoxylin and eosin staining and the pathological lymph node compartments, by cytokeratin-positive nodes, were prognostic factors by multivariate analysis. Conclusions. We demonstrated a high rate of MM or TCM in the paraaortic lymph nodes and suggest that such harbored metastases are related to the prognosis of patients with advanced gastric carcinoma. On the basis of this study, a multi-institutional study should be considered.

Disseminated cancer cells in the blood and expression of sialylated antigen in gastric cancer

BACKGROUND In gastric cancer, disseminated cancer cells (DCC) can be detected in peripheral blood using bio-molecular techniques. It is known that patients having DCC exhibit a high occurrence of postoperative relapse in gastrointestinal cancer. However, more than half of gastric cancer patients having positive DCC do not show cancer relapse. Sialylated Lewis antigens are considered to be crucial molecules in the metastasis of disseminated cancer. The current study investigated whether combination analysis of DCC and sialylated Lewis antigen are useful in estimating the recurrence risk of gastric cancer. PATIENTS AND METHODS Subjects were 106 consecutive gastric cancer patients who underwent curative gastrectomy. DCC in the peripheral blood were detected using the carcinoembryonic antigen (CEA)-mRNA by RT-PCR method. Sialylated Lewis antigen expression (sLeA and sLeX) of the primary tumor was assessed immunohistochemically. RESULTS Of 106 gastric cancer patients, 43 (40%) were positive for DCC. Immunohistochemically, 53 (50%) and 49 (46%) patients were positive for sLeA and sLeX, respectively. The presence of DCC did not correlate with sLeA and sLeX expression in gastric cancer. Postoperative tumors were present in 19 patients (7 hematogenous and 12 non-hematogenous), 12 of which were positive for DCC. Six sLeA-positive patients (26%) with DCC and 13 sLeX-positive patients (57%) with DCC suffered from postoperative recurrence of gastric cancer. The p value of CEA-mRNA and sLeX combination analysis was more significant (p<0.01) than that of CEA-mRNA alone (p=0.02). CONCLUSION Analyzing both DCC and sLeX expression in gastric cancer may enable more accurate prediction of postoperative recurrence.

Effect of neoadjuvant chemotherapy for lymph node micrometastasis and tumor cell microinvolvement in the patients with esophageal carcinoma

Micrometastasis (MM) and tumor cell microinvolvement (TCM) in the lymph node were immunohistochemically evaluated using the cytokeratin (CK) antibody between a surgery group (n=20; 929 lymph nodes) and a chemotherapy group (n=20; 1052 lymph nodes). The incidence of MM+/-TCM in the surgery and chemotherapy groups was 50.0 (10/20) and 55.0% (11/20), respectively. Limiting the analysis to TCM alone revealed that the incidence in the chemotherapy group (10.0%; 2/20) was significantly lower than that in the surgery group (40.0%; 8/20; P=0.032). Preoperative chemotherapy in this regime was not effective, except for some patients with TCM alone.