Hirotomi Cho

Indocyanine green fluorescence imaging system for sentinel lymph node biopsies in early breast cancer patients.

PurposeThis study presents a new method that enables the detection of sentinel lymph nodes (SLN) with high sensitivity using indocyanine green (ICG) fluorescence imaging.MethodsThis study enrolled 128 patients with clinically node-negative breast cancer. Fluorescence imaging was obtained after ICG was injected into the areola. Subcutaneous lymphatic channels were immediately visible.ResultsLymphatic channels and SLN were successfully visualized in all patients. One lymphatic channel was 60%, two channels were 24%, and three channels were 16%. The number of fluorescence SLN ranged from 1 to 6, and blue-dyed SLN ranged from 0 to 3. In the latter, SLN were not identified in 44 patients. Nineteen patients had pathologically identified lymph node metastases. All of them were recognized by fluorescence imaging, but 8 patients had lymph nodes with metastases were not identified by dye method.ConclusionThis ICG fluorescence imaging technique is feasible and safe for detecting SLN in a less invasive manner than conventional mapping, with real-time observations.

Peripheral nerve regeneration by transplantation of BMSC-derived Schwann cells as chitosan gel sponge scaffolds

It is said that bone marrow stromal cells (BMSCs) are able to differentiate into different kinds of cells, including Schwann cells, under relevant conditions (Dezawa et al., Eur J Neurosci 2001;14:1771-1776). In the previous paper, we demonstrated that chitosan gel sponge is one of the effective scaffolds for regenerating axons of the rat sciatic nerve (Ishikawa et al., J Biomed Mater Res A 2007;83:33-40). In the present study, we examined whether BMSC-derived Schwann cells with chitosan gel sponges were one of the effective scaffolds for peripheral nerve regeneration in rats. BMSC-derived cells with Schwann cell characteristics were labeled by green fluorescent protein using a retrovirus. An 8-mm gap was made by removing a nerve segment from the rat peripheral nerve, and chitosan gel sponges containing BMSC-derived Schwann cells were grafted, sandwiching the proximal and distal stumps of the transected nerve. Rats were sacrificed at 7, 14, and 28 days, and 2 and 4 months after transplantation. Immunohistochemistry demonstrated that regenerating axons were found near transplanted Schwann cells 7 days after surgery and extended into the host distal nerve segment at 14 days after surgery. Electron microscopy showed that transplanted Schwann cells formed myelin sheaths on regenerating axons 1 month after transplantation. The mean diameter of myelinated fibers was increased from 2.58 mum at 2 months to 2.84 mum at 4 months postsurgery. This study indicates that chitosan gel sponges containing BMSC-derived Schwann cells have strong potentiality as a graft that can be used for peripheral nerve regeneration.

Abstract P1-15-11: The Kampo medicine Goshajinkigan prevents docetaxel-related peripheral neuropathy in breast cancer patients

Background: Although taxanes have become a key chemotherapeutic drug in breast cancer treatment. Taxanes inhibit the growth of cancer cells by disrupting the functioning of their microtubules; however, the microtubules of nerve cells are also affected by this process, which can cause neurological disorders. The Kampo medicine Goshajinkigan (GJG) is a traditional Japanese medicine that is used for the treatment of several neurological symptoms including pain and numbness, GJG is comprised of 10 herbs, each of which contains numerous active ingredients. Recently, GJG has been reported to prevent anticancer drug-induced peripheral neuropathy in colorectal cancer. We performed the present prospective randomized study to confirm the effects of GJG and mecobalamin (B12) against docetaxel (DOC)-associated peripheral neurotoxicity in breast cancer patients. Patients and method: Between May 2007 and April 2011, 60 breast cancer patients were treated with DOC. Thirty-three patients (GJG group) received oral administration of 7.5 g/day GJG and 27 patients (B12 group) received oral administration of 1500 μg/day B12. The patients were treated with TC (75mg/m 2 docetaxel and 600 mg/m 2 cyclophosphamide) every 3 weeks for 4 cycles, docetaxel alone (100mg/m 2 ) every 3 weeks for 4 cycles, and XT (900mg/m 2 capecitabine administered orally twice a day on days 1–14 plus 60 mg/m 2 docetaxel) every 3 weeks for 6 cycles. Peripheral neuropathy was evaluated during every course according to DEB-NTC (Neurotoxicity Criteria of Debiopharm), Common Terminology Criteria for Adverse Events (NCI-CTC) ver.3.0, and a visual analogue scale (VAS). Results: The median age of the GJG group was 58 years old (35 to 70 years old), the B12 group was 55 years old (33 to 69 years old), and they were all females. For the regimens, in the GJG group, TC, DOC only, and XT were administered in 19 cases, 13 cases and 1 case, respectively. In the B12 group, they were 15 cases, 11 cases and 12 cases, respectively. The cumulative dose of DOC was 338.5 mg/m2 in the GJG group, and 340 mg/m2 in the B12 group. Peripheral neuropathy occurred significantly less frequently in the GJG group (39.3%) than the B12 group (88.9%) (p Conclusion: The present study is the first prospective control study to prove the efficacy of GJG against docetaxel-induced peripheral neuropathy in breast cancer patients. Our findings suggest that DOC-associated peripheral neurotoxicity can be suppressed by the administration of GJG. It will be necessary to confirm the usefulness of GJG in larger prospective studies. Citation Information: Cancer Res 2012;72(24 Suppl):Abstract nr P1-15-11.

New fluorescence imaging method for sentinel lymph node biopsy in patients with early breast cancer.

e11578 Background: Indocyanine green (ICG) is a popular diagnostic reagent for the examination of hepatic function and cardiac output. In this study, based on the fluorescence characteristics of ICG, we present a new method that enables the detection of sentinel lymph nodes (SLN) with high sensitivity using ICG fluorescence imaging. METHODS Fluorescence images were obtained using the fluorescence imaging system, the Photodynamic Eye (Hamamatsu Photonics Co., Japan). A 0.5% ICG solution combined with Indigocarmine was intradermally injected for 0.3 ml in the areola closest to a tumor. Subcutaneous lymphatic channels draining from the areola to the axilla or other directions were visible by fluorescence imagings immediately. The point where the fluorescence disappeared was identified on the skin, and the skin has been pressed with the capsule. The point of fluorescence seemed was then incised, and the SLN were then dissected by fluorescence navigation. RESULTS This study enrolled 202 patients with clinically node-negative breast cancer. Their average age was 53.9 years (ranged from 29 to 82 years). Sixty five patients were premenopausal, and 137 patients were postmenopausal. There were five cases of Tis lesions and 117 cases with T1 lesions and 80 cases with T2 lesions. Subcutaneous lymphatic channels and SLN were successfully visualized in all patients. One lymphatic channel to the axilla was 53%, two channels were 32%, and three channels were 16%. The channels to other directions were not seen. The number of fluorescent SLN ranged from 1 to 6 (mean: 3.1), and blue dyed SLN ranged from 0 to 3 (mean: 1.2). In the latter, SLN were not identified in 76 patients (identification rate: 62.4%). Twenty three patients had lymph node metastases pathologically. All of them were recognized by fluorescence imagings, but, in 10 patients, lymph nodes with metastases were not identified by a blue dye. CONCLUSIONS The fluorescence imaging method is therefore considered to be a new and effective method for SLN mapping, which allows easy, highly sensitive and real-time imaging-guided SLN mapping in patients with early breast cancer. The current results show that SLN mapping guided by ICG fluorescence imaging could therefore be a promising tool.

Abstract 1939: Augmenting effector function and abrogating Treg function by OX40 costimulation enhances adoptive transfer tumor-specific CTL response

Proceedings: AACR 101st Annual Meeting 2010‐‐ Apr 17‐21, 2010; Washington, DC We have recently shown that OX40 (CD134) costimulation provided with GM-CSF-secreting vaccine can bypass CD8+ T cell tolerance. OX40 costimulation can also abrogate Foxp3+ regulatory T cell (Treg)-mediated suppression of antitumor immunity by reducing Foxp3 expression on Tregs. In addition, OX40 costimulation can directly augment tumor-specific CTL function without CD4+ T cell help in vivo. Here we show that pre-treatment with agonistic anti-OX40 mAb augments the antitumor immune effects of adoptive CD8+ T cell therapy in the clinically relevant wild-type model, not TCR-transgenic, mouse model. CD8+ T cells stimulated with tumor antigen (HER2/neu immunodominant peptide and T2 cells), including a small number of tumor antigen-specific effector CD8+ T cells, were transferred into tumor-bearing FVB/N mice. We could detect the response of tumor antigen-specific CD8+ T cells that were adoptively transferred into the recipient mice, however, the response was not sufficient to eradicate an established tumor. In addition, we showed that pre-treatment with OX40 costimulation in tumor-bearing recipient in order to inhibit the Treg-mediated suppressive function enhanced tumor specific immune response of adoptively transferred CD8+ T cells in the recipients, thus resulting in the eradication of an established tumor. Moreover, adoptively transferred CTLs, with OX40 costimulation in vitro before transfer, significantly enhanced a tumor-specific immune response in the tumor-bearing recipient. Furthermore, when tumor antigen-specific CTLs costimulated through OX40 in vitro were adoptively transferred into the tumor-bearing recipients that had been pre-treated with OX40 costimulation to inhibit Treg function, transferred tumor-specific CTLs were effectively maintained in this recipient 7 times more than in the recipient with CTL transfer alone without OX40 treatment, and about 3 times more than in the recipient with a single treatment of OX40 costimulation. These findings therefore suggest that both direct enhancement of adoptive transfer CTL function and pre-inhibition of Treg-mediated suppressive function in recipients with OX40 costimulation are useful strategy for antitumor adoptive CTL therapy. Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 101st Annual Meeting of the American Association for Cancer Research; 2010 Apr 17-21; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2010;70(8 Suppl):Abstract nr 1939.