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50 result(s) for "TASHIRO, YOSHIHIKO"
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Oral recombinant methioninase combined with paclitaxel arrests recalcitrant ovarian clear cell carcinoma growth in a patient-derived orthotopic xenograft (PDOX) nude-mouse model
PurposeAdvanced ovarian clear cell carcinoma (OCCC) is a recalcitrant disease, often resistant to the first-line platinum-based therapy. Using a novel patient-derived orthotopic xenograft (PDOX) nude-mouse model of OCCC, we tested whether oral-recombinant methioninase (o-rMETase) could enhance the efficacy of paclitaxel (PTX).MethodsThe OCCC PDOX model was established and passaged in nude mice. The OCCC PDOX models were randomized into 5 groups. G1: untreated control; G2: paclitaxel (PTX) (20 mg/kg, intraperitoneal (i.p.) injection, weekly); G3: o-rMETase (100 units, oral, daily); G4: PTX (20 mg/kg, i.p. injection, weekly) + carboplatinum (CBDCA) (40 mg/kg, i.p. injection weekly); G5: PTX (20 mg/kg, i.p. injection, weekly) + o-rMETase (100 units, oral, daily). The treatment period was 2 weeks.ResultsThe combination of PTX and o-rMETase arrested OCCC tumor growth (relative tumor volume: 1.09 ± 0.63 (mean ± SD)) compared with the untreated control (relative tumor volume: 3.92 ± 1.04 (mean ± SD)) (p < 0.0001). There was no significant difference in relative tumor volume between PTX plus o-rMETase and PTX plus CBDCA (relative tumor volume: 1.39 ± 0.37 (mean ± SD)) (p = 0.93).ConclusionPTX plus o-rMETase arrested the OCCC tumor growth. o-rMETase is readily administered and can greatly enhance first-line therapy of a recalcitrant cancer. The novel and effective treatment strategy in the present report has future clinical potential for patients with OCCC, especially for patients who cannot well tolerate platinum-based therapy.
Laparoscopic Liver Surgery Guided by Virtual Real-time CT-Guided Volume Navigation
Background Recently, virtual navigation system has been applied to hepatic surgery, enabling better visualization of intrahepatic vascular branches and location of tumor. Intraoperative ultrasonography (IOUS) is the most common form of image guidance during liver surgery. However, during laparoscopic hepatectomies (LH), IOUS has several limitations and its reliability has been poorly evaluated. The objective of this work is to evaluate VRCT (virtual real-time CT-guided volume navigation) during LH. This system aims to provide accurate anatomical orientation for surgeons enhancing the safety of LH. Methods Twenty-seven hepatic neoplasms were resected laparoscopically at our institution under reference guidance of VRCT. During operation, electromagnetic tracking of the surgical instrument was used for navigating the direction of accurate liver transection. Results Twenty-six (96.3%) of the 27 lesions (mean diameter 11 mm) were successfully performed under VRCT guidance. Average registration time was < 2 min. Average setup time was approximately 7 min per procedure. VRCT allows the surgeon to navigate liver transection with acceptable accuracy. The mean error was 12 mm. All surgical margins were negative and the mean histologic resection margin was 9 mm. Conclusions VRCT-guided LH is feasible and provides valuable real-time anatomical feedback during hepatic resections. Advancement of such systems to improve accuracy might greatly compensate for the limitation of laparoscopic IOUS.
Development of a Novel Artificial Intelligence System for Laparoscopic Hepatectomy
Laparoscopic hepatectomy (LH) requires accurate visualization and appropriate handling of hepatic veins and the Glissonean pedicle that suddenly appear during liver dissection. Failure to recognize these structures can cause injury, resulting in severe bleeding and bile leakage. This study aimed to develop a novel artificial intelligence (AI) system that assists in the visual recognition and color presentation of tubular structures to correct the recognition gap among surgeons.BACKGROUND/AIMLaparoscopic hepatectomy (LH) requires accurate visualization and appropriate handling of hepatic veins and the Glissonean pedicle that suddenly appear during liver dissection. Failure to recognize these structures can cause injury, resulting in severe bleeding and bile leakage. This study aimed to develop a novel artificial intelligence (AI) system that assists in the visual recognition and color presentation of tubular structures to correct the recognition gap among surgeons.Annotations were performed on over 350 video frames capturing LH, after which a deep learning model was developed. The performance of the AI was evaluated quantitatively using intersection over union (IoU) and Dice coefficients, as well as qualitatively using a two-item questionnaire on sensitivity and misrecognition completed by 10 hepatobiliary surgeons. The usefulness of AI in medical education was qualitatively evaluated by 10 medical students and residents.PATIENTS AND METHODSAnnotations were performed on over 350 video frames capturing LH, after which a deep learning model was developed. The performance of the AI was evaluated quantitatively using intersection over union (IoU) and Dice coefficients, as well as qualitatively using a two-item questionnaire on sensitivity and misrecognition completed by 10 hepatobiliary surgeons. The usefulness of AI in medical education was qualitatively evaluated by 10 medical students and residents.The AI model was able to individually recognize and colorize hepatic veins and the Glissonean pedicle in real time. The IoU and Dice coefficients were 0.42 and 0.53, respectively. Surgeons provided a mean sensitivity score of 4.24±0.89 (from 1 to 5; Excellent) and a mean misrecognition score of 0.12±0.33 (from 0 to 4; Fail). Medical students and residents assessed the AI to be very useful (mean usefulness score, 1.86±0.35; from 0 to 2; Excellent).RESULTSThe AI model was able to individually recognize and colorize hepatic veins and the Glissonean pedicle in real time. The IoU and Dice coefficients were 0.42 and 0.53, respectively. Surgeons provided a mean sensitivity score of 4.24±0.89 (from 1 to 5; Excellent) and a mean misrecognition score of 0.12±0.33 (from 0 to 4; Fail). Medical students and residents assessed the AI to be very useful (mean usefulness score, 1.86±0.35; from 0 to 2; Excellent).The novel AI presented was able to assist surgeons in the intraoperative recognition of microstructures and address the recognition gap among surgeons to ensure a safer and more accurate LH.CONCLUSIONThe novel AI presented was able to assist surgeons in the intraoperative recognition of microstructures and address the recognition gap among surgeons to ensure a safer and more accurate LH.
Pathological Validity of Using Near-infrared Fluorescence Imaging for Securing Surgical Margins During Liver Resection
Background/Aim: This study investigated the use of near-infrared fluorescent imaging for securing safe margins during liver resection. Patients and Methods: This study included 125 patients who underwent liver tumor resection in 2014-2018. Indocyanine green testing was performed 2-14 days before surgery. Histopathological specimens of hepatocellular carcinoma (HCC) and colorectal liver metastasis (CRLM) were evaluated using fluorescent microscopy. Results: Fluorescence microscopy identified signals in 26/53 (49.0%) and 36/72 (50%) cases of HCC and CRLM, respectively. HCC demonstrated total, partial, rim, and combined fluorescence patterns; CRLM uniformly demonstrated rim fluorescence. Although rim fluorescence was seen in both HCC and CRLM, no malignancy was confirmed pathologically in the peritumoral area demonstrating fluorescence. The median widths of fluorescence from the tumor edge in HCC and CRLM were 1227.5 μm and 1608 μm, respectively, with no significant difference. Conclusion: Near-infrared fluorescent imaging can reliably detect safe surgical margins intraoperatively during liver resection.
Laparoscopic Anatomical Liver Resection Using Liver Mapping of Incidental Indocyanine Green Fluorescence due to Cholestasis
Indocyanine green (ICG) fluorescence is useful in laparoscopic hepatectomy (LH) for tumor identification and staining, as well as determination of resection margins. At our Institution, patient-specific, three-dimensional simulations and rehearsal of surgical strategies are carried out preoperatively. We describe cases in which ICG administered preoperatively became stagnated and fluoresced in an area similar to the preoperatively established resection area and the pathological findings in these cases.BACKGROUND/AIMIndocyanine green (ICG) fluorescence is useful in laparoscopic hepatectomy (LH) for tumor identification and staining, as well as determination of resection margins. At our Institution, patient-specific, three-dimensional simulations and rehearsal of surgical strategies are carried out preoperatively. We describe cases in which ICG administered preoperatively became stagnated and fluoresced in an area similar to the preoperatively established resection area and the pathological findings in these cases.Four patients who underwent LH at our hospital between 2020 and 2023 (due to hepatocellular carcinoma in two and colorectal liver metastasis in two) were enrolled in the present study. The ICG-fluorescing liver segments were resected laparoscopically and their pathological characteristics were examined using a fluorescence microscope.PATIENTS AND METHODSFour patients who underwent LH at our hospital between 2020 and 2023 (due to hepatocellular carcinoma in two and colorectal liver metastasis in two) were enrolled in the present study. The ICG-fluorescing liver segments were resected laparoscopically and their pathological characteristics were examined using a fluorescence microscope.In four cases, the areas of ICG fluorescence seen intraoperatively were due to stasis of preoperatively administered ICG, which fortuitously was equivalent to the planned resection area in the preoperative patient-specific simulation. The fluorescent areas were resected; there were no cases of bile leakage or recurrence. Fluorescence microscopy revealed areas with diffuse ICG fluorescence in normal hepatocytes on the tumor's peripheral side.RESULTSIn four cases, the areas of ICG fluorescence seen intraoperatively were due to stasis of preoperatively administered ICG, which fortuitously was equivalent to the planned resection area in the preoperative patient-specific simulation. The fluorescent areas were resected; there were no cases of bile leakage or recurrence. Fluorescence microscopy revealed areas with diffuse ICG fluorescence in normal hepatocytes on the tumor's peripheral side.It was suggested that resection of the liver area that was fluorescent due to stagnation of preoperatively administered ICG was rational and justified both anatomically and oncologically. This resection may also contribute to the prevention of bile leakage and recurrence.CONCLUSIONIt was suggested that resection of the liver area that was fluorescent due to stagnation of preoperatively administered ICG was rational and justified both anatomically and oncologically. This resection may also contribute to the prevention of bile leakage and recurrence.
Indocyanine Green Labeling of Tumors in the Liver Recurring After Radiofrequency Ablation Enables Complete Resection by Fluorescence-guided Surgery
Radiofrequency ablation (RFA) is used to treat primary and metastatic tumors in the liver. However, local recurrence after RFA is frequent and subsequent salvage hepatectomy is often ineffective due to difficulty in visualization of tumor margins. In the present retrospective clinical trial, seven patients from the Department of General and Gastro-enterological Surgery, Showa University School of Medicine underwent salvage hepatectomy for recurrent hepatocellular carcinoma (HCC) (n=2), colorectal liver metastasis (n=4) and lung-carcinoid liver metastasis (n=1), after RFA, between 2011 and 2020. Tumors were labeled with indocyanine green (ICG) and resected under fluorescence guidance. Resected specimens were evaluated under fluorescence microscopy as well as by standard histopathological techniques. Pathological findings revealed negative tumor margins in all patients after fluorescence-guided surgery. Six of seven resected tumors had a fluorescent rim, including both HCC and liver metastasis. Fluorescence microscopy demonstrated that viable cancer tumor cells were located only on the inside of the fluorescent rim, and no malignant cells were detected within the fluorescent rim surrounding the tumor. Fluorescence microscopy showed that the tumor margin was secured if the fluorescence signal was completely resected. The present results demonstrate that ICG labeling of liver tumors recurring after RFA enabled complete resection under fluorescence guidance. The present study is the first clinical study to demonstrate that tumor types that generally cannot be completely resected with bright light are fully resectable under fluorescence guidance.
Obesity Strongly Promotes Growth of Mouse MC38 Colon Cancer in an Orthotopic-syngeneic C57BL/6 Mouse Model
Background/Aim: Obesity is a major risk factor for colorectal cancer. The MC38 mouse colon-cancer cell line is a versatile syngeneic model of colon cancer in C57BL/6 mice. In the present study, the influence of a high-fat diet (HFD) on the growth of the MC38 mouse colon-cancer cell line was examined in an orthotopic-transplantation syngeneic model in C57BL/6 mice. Materials and Methods: Five 6-week-old C57BL/6 male mice were fed a control diet (CD, 6.5% fat) or HFD (34.3% fat) for eight weeks. Then, a 2 mm3 fragment of a subcutaneous MC38 tumor was attached to the surface of the cecum of C57BL/6 mice with a single stitch using a 7-0 suture to establish an orthotopic-transplantation model. Each group continued their initial diet for 17 days. Results: The HFD group had more than twice the tumor volume and tumor weight than the CD group (p=0.021 and p=0.014, respectively). Conclusion: HFD-induced obesity strongly increased MC38 colon-cancer progression in a C57BL/6 orthotopic-transplantation mouse model. The present study emphasizes the detrimental effect of obesity on coloncancer progression.
Response of Triple-negative Breast Cancer Liver Metastasis to Oral Recombinant Methioninase in a Patient-derived Orthotopic Xenograft (PDOX) Model
The aim of this study was to establish a patient-derived orthotopic xenograft (PDOX) mouse model of liver metastasis of triple-negative breast cancer (TNBC) and examine the efficacy of oral recombinant methioninase (o-rMETase) on the liver metastasis. TNBC from a patient was implanted in the left hepatic lobe of nude mice to simulate liver metastasis in a PDOX model. Ten days later, all mice underwent laparotomy to measure tumor size and were randomized to three groups: control; o-rMETase 100 U once daily (qd); and o-rMETase 200 U qd. After 9 days of treatment, all mice were sacrificed. At the end of the treatment period for the liver metastasis, the size of liver metastases was 372.6 mm in the control group; 160.0 mm in the o-rMETase 100 U group; and 245.3 mm in the o-rMETase 200 U group. All mice had ascites and 12 out of 14 mice in all groups had mesenteric lymph-node metastasis, as re-metastasis. The mean body-condition score was 1.5 in the control group; 2.4 in the o-rMETase 100 U group; and 2.6 in the o-rMETase 200 U group (control group vs. o-rMETase 200 U group, p<0.05). The TNBC liver metastasis was highly aggressive resulting in re-metastasis and ascites. o-rMETase tended to inhibit the liver metastasis and significantly improved the mouse body-condition score. This new PDOX model of TNBC liver metastasis will be useful for identifying effective agents for this recalcitrant disease.
Intraoperative Shear Wave Elastography as a Quantitative Predictor of Pancreatic Fibrosis and Exocrine Function
Soft pancreatic texture is a risk factor for postoperative pancreatic fistula (POPF). However, conventional evaluation of pancreatic texture is largely dependent on subjective assessment and lacks quantitative parameters. The study aimed to use ultrasonic shear wave elastography (SWE) to evaluate pancreatic stiffness to determine if the intraoperative SWE measurement could be a quantitative predictor for POPF. Fifteen patients scheduled for pancreaticoduodenectomy were included. Both pre- and intra-operative measurement of the pancreatic SWE index (SWEI) were evaluated. Relationships between intraoperative and preoperative SWEI, pathological fibrosis of the resected pancreatic specimen, postoperative exocrine function of the remnant pancreas, and the incidence of POPF were evaluated. The intraoperative SWEI was correlated with the preoperative SWEI, pathological fibrosis of pancreatic tissue, and pancreatic exocrine function. Intraoperative SWE measurement of pancreatic elasticity may be useful as a quantitative method for evaluating pancreatic fibrosis and exocrine function.
A Gemcitabine Plus 5-Fluorouracil Combination Inhibits Gastric-Cancer Liver Metastasis in a PDOX Model: A Novel Treatment Strategy
Background/Aim: We established a new patient-derived orthotopic xenograft (PDOX) model of gastric cancer liver metastasis and evaluated the efficacy of a novel combination chemotherapy, gemcitabine (GEM) plus 5-fluorouracil (5-FU), compared to a standard regimen of oxaliplatinum (L-OHP) plus 5-FU on the liver metastasis. Materials and Methods: Patient-derived gastric cancer was established in nude mice from the patient' s surgical tumor specimen. A single tumor fragment was implanted in the liver of nude mice. The mice with tumors were treated by GEM plus 5-FU or L-OHP plus 5-FU. Results: GEM plus 5-FU or L-OHP plus 5-FU significantly and similarly inhibited tumor growth on the liver compared to the untreated control (p=0.007, p=0.02, respectively). Conclusion: GEM plus 5-FU could be a novel future clinical alternative to L-OHP plus 5-FU in gastric cancer patients who cannot tolerate platinum drugs.