Assessment for diagnosis of lymph node metastasis in esophageal cancer using endoscopic ultrasound elastography.

BACKGROUND: We performed endoscopic ultrasound real-time tissue elastography to more accurately diagnose lymph node metastasis of esophageal cancer. The aim of this study was to evaluate the ability of EUS elastography to distinguish benign from malignant lymph nodes in esophageal cancer patients. METHODS: The present study had two steps. As the first step (study 1), we developed diagnostic criteria for metastatic lymph nodes using elastography and verified the validity of the criteria. Three hundred and twenty-two lymph nodes from 35 patients treated by surgical resection were included in the study. As the second step (study 2), we preoperatively examined the lymph nodes of esophageal cancer patients with EUS elastography and compared its diagnostic performance with that of the conventional B-mode EUS images. A total of 115 lymph nodes from 31 patients were included. RESULTS: In study 1, lymph nodes were considered malignant if 50 % or more of the node appeared blue, or if the peripheral part of the lesion was blue and the central part was red/yellow/green. The sensitivity and specificity of the elastography were 79.7 and 97.6 % with an accuracy of 93.8 %, which was significantly higher than the values for conventional B-mode imaging. In study 2, the sensitivity and specificity of the EUS elastography were 91.2 and 94.5 % with an accuracy of 93.9 %, which was also significantly higher than the values for conventional B-mode EUS imaging. CONCLUSIONS: The present study demonstrated that EUS elastography is useful for diagnosing lymph node metastasis of esophageal cancer.

Survival predictors of patients with primary duodenal adenocarcinoma.

This single-institution experience retrospectively reviewed the outcomes in 21 patients with primary duodenal adenocarcinoma. Twelve patients underwent curative surgery, and 9 patients underwent palliative surgery at the Chiba University Hospital. The maximum follow-up period was 8650 days. All pathologic specimens from endoscopic biopsy and surgical specimens were reviewed and categorized. Twelve (57.1%) patients underwent curative surgery (R0): 4 pancreaticoduodenectomies (PD), 4 pylorus-preserving PDs (PpPD), 2 local resections of the duodenum and 2 endoscopic mucosal resections (EMR). Palliative surgery was performed for 9 patients (42.9%) following gastro-intestinal bypass. The median cause-specific survival times were 1784 days (range 160-8650 days) in the curative surgery group and 261 days (range 27-857 days) in the palliative surgery group (P = 0.0003, log-rank test). The resectability of primary duodenal adenocarcinoma was associated with a smaller tumor size, a lower degree of tumor depth invasiveness, and less spread to the lymph nodes and distant organs.

RIG-I helicase-independent pathway in sendai virus-activated dendritic cells is critical for preventing lung metastasis of AT6.3 prostate cancer.

We recently demonstrated highly efficient antitumor immunity against dermal tumors of B16F10 murine melanoma with the use of dendritic cells (DCs) activated by replication-competent, as well as nontransmissible-type, recombinant Sendai viruses (rSeV), and proposed a new concept, "immunostimulatory virotherapy," for cancer immunotherapy. However, there has been little information on the efficacies of this method: 1) in more clinically relevant situations including metastatic diseases, 2) on other tumor types and other animal species, and 3) on the related molecular/cellular mechanisms. In this study, therefore, we investigated the efficacy of vaccinating DCs activated by fusion gene-deleted nontransmissible rSeV on a rat model of lung metastasis using a highly malignant subline of Dunning R-3327 prostate cancer, AT6.3. rSeV/dF-green fluorescent protein (GFP)-activated bone marrow-derived DCs (rSeV/dF-GFP-DC), consistent with results previously observed in murine DCs. Vaccination of rSeV/dF-GFP-DC was highly effective at preventing lung metastasis after intravenous loading of R-3327 tumor cells, compared with the effects observed with immature DCs or lipopolysaccharide-activated DCs. Interestingly, neither CTL activity nor DC trafficking showed any apparent difference among groups. Notably, rSeV/dF-DCs expressing a dominant-negative mutant of retinoic acid-inducible gene I (RIG-I) (rSeV/dF-RIGIC-DC), an RNA helicase that recognizes the rSeV genome for inducing type I interferons, largely lost the expression of proinflammatory cytokines without any impairment of antitumor activity. These results indicate the essential role of RIG-I-independent signaling on antimetastatic effect induced by rSeV-activated DCs and may provide important insights to DC-based immunotherapy for advanced malignancies.

Carbon-ion beam treatment induces systemic antitumor immunity against murine squamous cell carcinoma.

BACKGROUND: Carbon-ion beam (CIB) treatment is a powerful tool for controlling primary tumors in the clinical setting. However, to date, few clinical or experimental studies have investigated the effects of CIB treatment on tumor recurrence and antitumor immunity. METHODS: A multiple challenge test was performed using syngenic and nude mouse models of a poorly immunogenic squamous cell carcinoma cell line (SCCVII) after CIB treatment at a clinically available dose (77 kiloelectron volts [keV]/microm) to primary tumors. To further examine changes in antitumor immunity in this model, the authors used dendritic cell (DC)-based immunotherapy. RESULTS: In a syngenic model, CIB treatment itself resulted not only in efficient elimination of the primary tumor but also in a dramatic reduction of tumor formation after secondary tumor challenge at a contralateral site (P<.0001). Conversely, CIB treatment eliminated neither the primary nor the secondary tumor in nude mice. This antitumor effect produced by CIB treatment was enhanced significantly by combining it with DC immunotherapy (P=.0007). Combined CIB and DC treatment induced more intense cytolytic activity than CIB in a chromium-release assay. The third challenge tests, which included challenge with a third-party tumor cell line (FM3A) and effector depletion, revealed that the antitumor effects were the results of tumor-specific, long-lasting antitumor immunity through CD8-positive T lymphocytes. CONCLUSIONS: To the authors' knowledge, this is the first demonstration of strong antitumor immunity induced by CIB treatment in a dermal tumor, and this effect was enhanced by combining it with DC-based immunotherapy. The authors concluded that this combination warrants further investigation as a promising modality for the prevention of tumor recurrence.

Development of immunostimulatory virotherapy using non-transmissible Sendai virus-activated dendritic cells.

Dendritic cell (DC)-based immunotherapy has been clinically evaluated, however, still requires modification to improve its outcomes. We previously demonstrated that DCs activated by replication competent recombinant Sendai virus (SeV) showed dramatic efficacy over that seen in use of current DC vaccine for immunotherapy against malignancies; however, application of replication-deficient vector is more relevant in clinical setting. We here show that F-gene-deleted non-transmissible Sendai virus (SeV/dF)-activated DCs (DCs/SeV/dF) has strong antitumor effects against murine SCCVII tumor, that was well-known as a less immunogenic cell line. SeV/dF shows high transfection efficiency to DCs and leads them to upregulate costimulatory molecules. Intratumoral injection of DCs/SeV/dF resulted in a marked and representative inhibition of the tumor, even when the tumors were well-vascularized. This is the first demonstration that non-transmissible SeV vector, SeV/dF, could be a DC-activator; DC/SeV/dF-based cancer immunotherapy may, therefore, warrant further investigation.