Short- and long-term outcomes of laparoscopic surgery with extracorporeal anastomosis for transverse colon cancer: comparison of triangulating anastomosis with functional end-to-end anastomosis.

BACKGROUND: We compared triangulating anastomosis (TRI) with functional end-to-end anastomosis (FEEA) in terms of patient demographics, clinicopathological features, and short- and long-term outcomes in this study. METHODS: From November 2005 to May 2016, 315 patients with transverse colon cancer underwent laparoscopic resection. TRI was performed in 62 patients and FEEA in 253 patients. Patients with another concomitant cancer, who received neoadjuvant chemotherapy, and/or who underwent another operation at the same time were excluded. RESULTS: The patients' backgrounds were comparable in each group. Transverse colectomy was selected more frequently in TRI and right hemicolectomy in FEEA. The operation time was shorter in TRI. The rate of anastomotic leakage was comparable (1.6% in TRI vs. 0.8% in FEEA). Stricture was more common in TRI (8.1% vs. 0%) and bleeding was more common in FEEA (1.6% vs. 10.6%). The rate of long-term complications was comparable in each group. Overall survival of stage 0-III patients was comparable in each group (94.7% in TRI vs. 93.7% in FEEA). 5-year disease-free survival of stage 0-III, stage II, and stage III patients was also comparable in each group (94.8% vs. 93.0%, 100% vs. 92.1%, and 80.3% vs. 79.2% in TRI and FEEA, respectively). CONCLUSION: The short- and long-term outcome rates were acceptable in both groups. Specific attempts to prevent complications are required for each anastomotic procedure.

Role of podoplanin and Kupffer cells in liver injury after ischemia-reperfusion in mice.

AIM: To investigate the relationship between the intrahepatic expression of podoplanin (PDPN) and Kupffer cells (KCs) in ischemia-reperfusion (I/R) liver damage. METHODS: C57Bl/6 mice were injected with 200 µl of clodronate liposomes (macrophage depletion; MDP group) to deplete KCs or control liposomes (control group) via the ophthalmic vein plexus 24 h prior to ischemia. Animals were subjected to 90 min of partial hepatic ischemia (70%), followed by reperfusion, and were then killed at designated time points. Serum and liver tissues were harvested for further analyses. RESULTS: Serum ALT levels, mortality rates, and the percentage of necrotic area in liver sections were significantly higher in the MDP group than in the control group. PDPN was expressed in the lymphatic epithelium, interlobular bile duct epithelium, and in some hepatocytes in each group. Its expression in hepatocytes was down-regulated in the MDP group. The accumulation of platelets in the sinusoid was reduced 6 h after I/R in the MDP group. Tissue HGF and IGF-1 levels decreased in the MDP group. CONCLUSIONS: These results suggest that KCs play a key role in the activation of platelets through direct contact with PDPN-positive hepatocytes in I/R livers.

[Long-Term Prognosis of Patients with Biliary Tract Cancer Undergoing Pancreaticoduodenectomy].

We divided the patients with biliary tract cancer who underwent pancreaticoduodenectomy(PD)at our hospital into the 5-year recurrence-free and recurrence groups and investigated the prognostic factors. Additionally, we investigated the efficacy of adjuvant chemotherapy in patients with and without lymph node (LN) metastasis. There was no significant difference between the two groups for patient characteristics and perioperative factors. However, patients with LN metastasis tended to have a higher recurrence rate. For patients without LN metastasis, the median overall survival(OS)was not significantly different between the patients who received and did not receive adjuvant chemotherapy. For patients with LN metastasis, although it was not significantly different(p=0.234), the OS of patients who received adjuvant therapy was more than 3 times than that of patients who did not(58.6 months and 18.4 months, respectively). For patients with biliary tract cancer who underwent PD, positive LN metastasis may be a poor prognostic factor, and adjuvant therapy may possibly improve prognosis.

[Pathological Complete Response of Intrapelvic Recurrence of Rectal Cancer after Chemoradiotherapy-A Case Report].

50's man who have performed anterior pelvic exenteration with lateral lymph node dissection for rectal cancer with pT4bN0M0, pStage Ⅱc about 2 years ago, was admitted to our hospital for the treatment of intrapelvic recurrence of rectal cancer. No distant metastasis was found in the computed tomography examination but the tumor invaded the dorsal side of the pubis. Because radical excision was impossible with these findings, he received chemoradiotherapy(CRT). Post-CRT imaging showed that the tumor of intrapelvic recurrence region reduced the size, and invasion of pubis had disappeared and been markedly reduced. Thus, radical excision seemed possible at this point, and we decided to attempt operation after total 6 weeks of S-1(120 mg/day)regimen and radiation(40 Gy/20 Fr). We performed Miles' operation. The final pathological examination demonstrated that no viable tumor cells remained in the resected rectum specimen, confirming that a pathological complete response(pCR)had been achieved.

Expression of podoplanin in stromal fibroblasts plays a pivotal role in the prognosis of patients with pancreatic cancer.

PURPOSE: To investigate the role of podoplanin (PDPN) expression in invasive ductal carcinoma of the pancreas (IDCP) in humans. METHODS: Tumor samples were obtained from 95 patients with IDCP. Immunohistochemical staining was done to evaluate the expression of PDPN in cancer tissues. RESULTS: PDPN was detected predominantly in stromal fibroblasts, stained with α-smooth muscle actin. The cutoff value of PDPN-positive areas was calculated according to a histogram. There was no significant difference in clinicopathologic factors between patients with high vs. those with low PDPN expression. The high PDPN group showed significantly poorer disease-free and disease-specific survival rates than the low PDPN group. Among patients from the high PDPN group, those with lymph node metastases and those with a tumor larger than 20 cm in diameter had significantly poorer prognoses than similar patients from the low PDPN group. Multivariate Cox proportional hazards analysis indicated that a high expression of PDPN was an independent risk factor for disease-specific survival. CONCLUSIONS: PDPN expression in cancer-related fibrotic tissues is associated with a poor prognosis, especially in patients with large tumors or lymph node metastases.

Interleukin-17A Plays a Pivotal Role in Chemically Induced Hepatocellular Carcinoma in Mice.

AIM: The aim of the present study was to investigate the role of interleukin (IL)-17A in the initiation and progression of hepatocellular carcinoma. METHODS: IL-17A deficient (KO) and wild-type (WT) mice were intraperitoneal injected with diethyl nitrosamine (DEN) to induce hepatocellular carcinoma, and the incidence of tumours was assessed 38 weeks later. In order to investigate the effects of DEN on hepatocytes in the acute phase of DEN administration, DEN-treated mice were sacrificed at designated time points. Serum and liver tissues were harvested for further analyses. RESULTS: The tumor incidence was approximately 65 % in WT mice, but was significantly lower (by 20 %) in KO mice. The number of tumours was also less in KO mice. Serum ALT levels increased in WT mice 7 days after the administration of DEN, but were significantly lower in KO mice. Furthermore, the number of neutrophils and Kupffer cells, and the expression of TNF-α and IL-6 were reduced in KO mice. The intrahepatic expression of the oxidative DNA damage marker 8-OHdG and lipid oxidative marker 4-HNE was markedly increased in WT mice, but was significantly lower in KO mice. In addition, the increase of cell proliferation, as assessed by Ki-67 immunohistochemistry, in WT mice was significantly reduced in KO mice. CONCLUSION: These results demonstrated that IL-17A plays a pivotal role in chemically induced hepatic carcinogenesis, which is most likely through inflammation-initiated oxidative DNA damage and cell proliferation.

Interleukin 17A plays a role in lipopolysaccharide/D-galactosamine-induced fulminant hepatic injury in mice.

BACKGROUND: Lipopolysaccharide/d-galactosamine (LPS/GalN)-induced hepatic injury is an experimental model of fulminant hepatic failure in which tumor necrosis factor alpha (TNF-α) plays a pivotal role. Moreover, it was reported from our laboratory that interleukin (IL) 17A enhanced production of TNF-α by the Kupffer cell. OBJECTIVE: The purpose of this study was to determine the role of IL-17A in LPS/GalN-induced hepatic injury in mice. METHODS: LPS/GalN was injected into three mouse models: wild-type (WT) mice, IL-17A knockout (KO) mice, or IL-17A KO mice treated with recombinant mouse (rm) IL-17A homodimer (KO + rmIL-17A). Survival was assessed for 24 h after LPS/GalN injection, and histopathologic findings were evaluated at various time points after LPS/GalN injection for neutrophil and apoptosis markers. After LPS/GalN injection, expression of the inflammatory mediators TNF-α, IL-6, monocyte chemotactic protein 1, IL-17A, high-mobility group box 1, and soluble intercellular adhesion molecule 1 was assessed in serum by enzyme-linked immunosorbent assay. RESULTS: Survival was higher in KO mice compared with WT mice after LPS/GalN injection. However, in KO + rmIL-17A mice, mortality was not significantly different compared to the other groups. Neutrophil infiltration and apoptosis were significantly greater in WT mice than KO mice. Furthermore, serum alanine aminotransferase, serum TNF-α, monocyte chemotactic protein 1, IL-17A, high-mobility group box 1, and soluble intercellular adhesion molecule 1 levels were also significantly greater in WT mice than KO mice. In KO + rmIL-17A mice, these levels were similar to those in WT mice. CONCLUSIONS: IL-17A is a key regulator in hepatic injury caused by neutrophil-induced inflammatory responses after LPS/GalN injection.

Macrophage colony-stimulating factor plays a pivotal role in chemically induced hepatocellular carcinoma in mice.

AIM: The specific purpose of this study was to investigate the role of macrophage colony-stimulating factor (M-CSF) in initiation and progression of hepatocellular carcinoma using M-CSF-deficient mice. METHODS: M-CSF-deficient (osteopetrotic: op/op) and their littermate (LM) mice were i.p. injected with diethylnitrosamine (DEN) to induce hepatocellular carcinoma. Twenty-eight weeks after DEN administration, the tumor incidence rate and serum M-CSF levels were assessed. Furthermore, distribution of the activated macrophages and the mRNA expression of CD163 and CD204 were evaluated. Moreover, angiogenesis was analyzed in tumors. In another set of experiments, apoptosis and proliferation of the hepatocytes were examined in the acute phase after DEN administration. Isolated hepatic macrophages were cultured with or without M-CSF, and vascular endothelial growth factor (VEGF) production was assessed by enzyme-linked immunoassay. RESULTS: Tumor incidence was significantly reduced in the op/op compared with the LM mice. Serum M-CSF levels were increased in the carcinogenesis models of the LM mice. Hepatic macrophages were found only in tumors in the op/op but in both normal liver tissue and tumors in the LM mice. In the op/op group, the mRNA expression of inflammatory cytokines was significantly lower compared with the LM mice. Furthermore, apoptosis was significantly increased in the op/op than the LM mice. Angiogenesis increased in liver tumors from the LM compared with the op/op mice. Production of VEGF was greater in the hepatic macrophages incubated with M-CSF compared with those without M-CSF. CONCLUSION: Thus, M-CSF is involved in the progression of chemically induced hepatocarcinogenesis.

Platelet activation receptor CLEC-2 regulates blood/lymphatic vessel separation by inhibiting proliferation, migration, and tube formation of lymphatic endothelial cells.

The platelet activation receptor CLEC-2 plays crucial roles in thrombosis/hemostasis, tumor metastasis, and lymphangiogenesis, although its role in thrombosis/hemostasis remains controversial. An endogenous ligand for CLEC-2, podoplanin, is expressed in lymphatic endothelial cells (LECs). We and others have reported that CLEC-2-deficiency is lethal at mouse embryonic/neonatal stages associated with blood-filled lymphatics, indicating that CLEC-2 is essential for blood/lymphatic vessel separation. However, its mechanism, and whether CLEC-2 in platelets is necessary for this separation, remains unknown. We found that specific deletion of CLEC-2 from platelets leads to the misconnection of blood/lymphatic vessels. CLEC-2(+/+) platelets, but not by CLEC-2(-/-) platelets, inhibited LEC migration, proliferation, and tube formation but had no effect on human umbilical vein endothelial cells. Additionally, supernatants from activated platelets significantly inhibited these three functions in LECs, suggesting that released granule contents regulate blood/lymphatic vessel separation. Bone morphologic protein-9 (BMP-9), which we found to be present in platelets and released upon activation, appears to play a key role in regulating LEC functions. Only BMP-9 inhibited tube formation, although other releasates including transforming growth factor-ß and platelet factor 4 inhibited proliferation and/or migration. We propose that platelets regulate blood/lymphatic vessel separation by inhibiting the proliferation, migration, and tube formation of LECs, mainly because of the release of BMP-9 upon activation by CLEC-2/podoplanin interaction.

Interleukin-17A plays a pivotal role in cholestatic liver fibrosis in mice.

BACKGROUND: It was recently reported that serum interleukin (IL)-17 levels increased in liver fibrosis associated with human alcoholic liver disease. However, the role of IL-17 in liver fibrosis has not yet been elucidated. Therefore, the aim of this study was to evaluate the role of IL-17 on cholestatic liver fibrosis. MATERIALS AND METHODS: IL-17A knockout (KO) and wild-type (WT) mice were subjected to bile duct ligation. Animals were sacrificed at designated times, and serum and liver tissues were collected. The mRNA expression of hepatic fibrotic markers was assessed, and distribution of activated hepatic stellate cells (HSCs) was determined by immunohistochemical staining. In an in vitro study, Kupffer cells (KCs) and HSCs were isolated from WT mice. KCs were cultured with IL-17A or IL-17F, and production of tumor necrosis factor α (TNF-α) and transforming growth factor ß1 (TGF-ß1) was measured. HSCs were cultured with IL-17A or IL-17F, and morphologic changes were assessed by immunohistochemical staining. RESULTS: Liver damage observed in the WT mice was significantly improved in the KO mice. Serum TNF-α and TGF-ß1 levels were significantly decreased in the KO compared with the WT mice. The hepatic mRNA expression of TNF-α, TGF-ß1, and collagen 1α1, which increased in the WT mice, also significantly decreased in the KO mice. Increased hepatic fibrosis in the WT mice was significantly improved in the KO mice. Cytokine production was increased in IL-17A-treated KCs. The most remarkable myofibroblast-like changes were observed in isolated HSCs in the presence of IL-17A. CONCLUSIONS: IL-17A was involved in the pathogenesis of cholestatic liver fibrosis by activation of both the KCs and HSCs.

Interleukin-17A plays a pivotal role after partial hepatectomy in mice.

BACKGROUND: Liver regeneration after partial hepatectomy (PH) is regulated by tumor necrosis factor (TNF)-α derived from the Kupffer cell. Furthermore, it was reported from our laboratory that interleukin (IL)-17A enhances the production of TNF-α by the Kupffer cell, suggesting that IL-17A may play a role in liver regeneration. OBJECTIVE: The purpose was to determine the role of IL-17A and the spleen in liver regeneration after PH. METHODS: Two mouse models including the wild-type (WT) mice or the IL-17A knockout (KO) mice underwent PH. Animals were killed at the designated time points; liver tissues were harvested for further investigation. Proliferation of hepatocytes was evaluated. Furthermore, the messenger RNA and protein expression of TNF-α and IL-6 were measured in the liver. In another set of experiments, the two animal models underwent splenectomy before PH. In an in vitro study, CD4-positive lymphocytes in the spleen were isolated from mice, and the number of IL-17A-positive cells was investigated. RESULTS: Liver regeneration was significantly impaired in the KO mice compared with the WT mice. This was associated with suppression of cell proliferation assessed by cell proliferation markers in the KO mice. In the WT mice that underwent splenectomy, liver regeneration was significantly delayed compared with animals without splenectomy. In contrast, splenectomy did not affect liver regeneration in the KO mice. IL-17A-positive lymphocytes increased significantly in the spleen in the WT mice after PH. CONCLUSIONS: These results indicate that IL-17A derived from CD4-positive lymphocytes in the spleen is a key regulator in liver regeneration after PH.

The Prognostic Implications of Perioperative Serum Cholesterol Levels in Patients With Gastric Cancer.

BACKGROUND/AIM: Although cholesterol is an important indicator of nutritional status, it is also involved in cancer progression. In this study, we investigated the clinical significance of the dynamics of perioperative total cholesterol (T-Cho) levels in patients with gastric cancer (GC). PATIENTS AND METHODS: A total of 212 patients with pathological stage II/III disease who underwent gastrectomy between 2004 and 2020 were enrolled in this retrospective study. The preoperative and postoperative serum T-Cho levels were measured in these patients. RESULTS: Increased serum T-Cho levels were significantly correlated with low preoperative serum albumin levels (p<0.001). Patients with increased serum T-Cho levels after surgery had significantly lower overall and recurrence-free survival rates (p=0.030 and p=0.013, respectively; log-rank test). Cox proportional hazards model revealed that increased serum T-Cho levels (p=0.040), advanced pathological stage (p<0.001), and the provision of adjuvant chemotherapy (p=0.006) were independent prognostic factors for recurrence-free survival in patients with GC. CONCLUSION: Increased serum T-Cho levels after gastrectomy may be an independent prognostic factor in patients with GC.

Prognostic effect of sarcopenia in colorectal cancer recurrence.

OBJECTIVES: Nutritional status significantly influences postoperative prognosis in gastrointestinal cancers. It has been evaluated using sarcopenia before treatments such as surgery and chemotherapy, despite constant changes in nutritional status. We consider that nutritional status at cancer recurrence is one of the important factors that affect treatment choice and intensity. This study evaluated the prognostic effects of improved postoperative nutritional status for people with colorectal cancer recurrence. METHODS: We enrolled 209 participants with pathologically confirmed stage II or III colorectal cancer who underwent radical resection. Sarcopenia was diagnosed using the psoas muscle index obtained from analysis of three-dimensional computed tomographic images. We adopted the cutoff value that was proposed by Hamaguchi et al. (psoas muscle index < 6.36 cm2/m2 for men and < 3.92 cm2/m2 for women). Evaluation was performed before surgery and at the time of recurrence. Participants with preoperative sarcopenia who relapsed were divided into two groups at the time of recurrence: sarcopenia continuation and sarcopenia improvement. We compared the prognosis of the two groups and examined the effect of postoperative nutritional improvement. RESULTS: Among the 209 participants, 81 (38.8%) had preoperative sarcopenia; this group had significantly lower overall survival than those without sarcopenia (P = 0.028). Colorectal cancer recurred in 48 participants. Of those 46, sarcopenia was evaluated at the time of recurrence; 19 of those 46 had preoperative sarcopenia. Preoperative sarcopenia did not affect the cancer recurrence ratio (sarcopenia, 23.5%; non-sarcopenia, 21.3%; P = 0.893). The sarcopenia-improvement group had higher overall survival than the sarcopenia-continuation group (P = 0.042). CONCLUSIONS: Among participants with preoperative sarcopenia, the prognosis at the time of recurrence improved for the sarcopenia-improvement group compared to the sarcopenia-continuation group. In people with colorectal cancer and sarcopenia, nutritional management is important not only before but also after surgery.

A case of simultaneous laparoscopic surgery for double cancer comprising multiple early gastric cancer and advanced sigmoid colon cancer after revascularization.

BACKGROUND: Traditionally, the surgery for simultaneous double cancer of the stomach and colon required a large incision to the upper and lower region of the abdomen. In this case, an artificial blood vessel was located under the skin after revascularization. Considering ischemia due to graft compression by incision retractor during laparotomy, this was difficult to do. This is a report on laparoscopic surgery for simultaneous double cancer of the stomach and colon after revascularization. CASE PRESENTATION: A 69-year-old man had early gastric cancer and advanced sigmoid colon cancer. He had suffered from thromboangitis obliterans and has undergone revascularization many times due to poor blood flow in his lower limbs. He had had some artificial blood vessels inserted under the skin, confirmed by blood vessel construction image by preoperative computed tomography (CT). There was a bypass vessel from the left axillary artery to the left femoral artery under the skin of the left thoracoabdominal. In addition, there were two bypass vessels from the left external iliac artery to the right femoral artery under the skin of the lower abdomen. One of the two bypasses was occluded. In the blood flow to the intestinal tract, the inferior mesenteric artery was already occluded. Peripheral blood flow in the common iliac artery depended on blood flow from the artificial blood vessel, and blood flow from the internal iliac artery to the rectum was poor. Laparoscopic Hartmann's operation was performed for Stage II B (UICC 8th Edition) sigmoid colon cancer. Because the blood flow in the intestinal tract on the anal side was poor, we thought that anastomosis was at a high risk for leakage. Laparoscopic total gastrectomy was also performed simultaneously for two Stage I (UICC 8th edition) gastric cancers in the cardia and body. The location of the port site and stoma was carefully determined preoperatively to prevent damage and infection to the artificial blood vessels. Minimal invasive surgery was performed using laparoscopic surgery. CONCLUSIONS: Laparoscopic surgery with small incisions is useful for patients with double cancer who need an approach to the upper and lower abdomen. Furthermore, laparoscopic surgery has less interference on graft in patients with artificial blood vessels under the skin by intraperitoneal approach.

Changes in Function and Dynamics in Hepatic and Splenic Macrophages in Non-Alcoholic Fatty Liver Disease.

BACKGROUND: The aim of this study was to investigate the populations and functions of hepatic and splenic macrophages (Mfs) in non-alcoholic fatty liver disease (NAFLD). MATERIALS AND METHODS: Experiment 1: Wild-type and STAM® mice were given chow or high-fat diets for designated periods. In isolated Mfs, phagocytosis and cytokine production were assessed. Immunohistochemistry for CD68 and F4/80 and expression of CD14 and CD16 were assessed. Experiment 2: Bone marrow cells harvested from enhanced green fluorescent protein (EGFP) mice were transplanted into wild-type mice with or without splenectomy after total body irradiation that was kept on methionine- and choline-deficient diets. RESULTS: Experiment 1: The number of CD68-positive cells and the percentage of F4/80-positive/CD68-positive cells increased with the progression of NAFLD. Production of TNF-α and IL-6 by hepatic Mfs was greater than that by splenic Mfs in mice with NASH. The number of CD14+CD16- Mfs increased in the spleen and decreased in the liver in animals that had progressed to NASH. Furthermore, the number of CD14+CD16+ hepatic Mfs was increased in animals that had progressed to NASH with fibrosis. Experiment 2: EGFP-positive cells were observed in the liver after transplantation. In the splenectomy group, EGFP-positive Mfs were also observed; however, the number was significantly less than that in the sham operation group. CONCLUSION: The populations and functions of hepatic and splenic Mfs are altered during the progression of NAFLD. In addition, increased hepatic Mfs during the progression of NAFLD may migrate from bone marrow to the liver via the spleen.

Laparoscopic-endoscopic cooperative surgery for ileal lipoma: A case report.

This is the first report of laparoscopic-endoscopic cooperative surgery (LECS) for an ileal tumor. A 50-year-old man was admitted to our hospital with a positive fecal occult blood test. Colonoscopy detected a submucosal tumor with intussusception located in the ileum, 10 cm oral from the Bauhin valve. On further examination, he was diagnosed with an ileal lipoma. There were no signs of malignancy. LECS was performed for the ileal tumor. After submucosal elevation by injecting saline solution, a mucosal incision was made circumferentially along the tumor. A full-thickness incision was created endoscopically and laparoscopically on the circumferential mucosal incisional line. The tumor was withdrawn intraluminally by endoscopy. The defect of the ileal wall was closed laparoscopically in an axial direction with linear staplers. Histologically, the tumor was a 25-mm ileal lipoma with negative resection margins and no malignancy.

Clinical Impact of Histological Heterogeneity in the Metastatic Lymph Nodes of Patients with Colorectal Cancer.

AIM: The purpose of this study was to evaluate the clinical impact of histological heterogeneity in patients with node-positive colorectal cancer (CRC). PATIENTS AND METHODS: One hundred and twenty-nine patients who underwent curative surgical resection for histological node-positive CRC were enrolled. Patients were divided according to the histological heterogeneity in the primary lesion into p-hetero and p-homo groups. The p-hetero group was further divided according to histological heterogeneity in the metastatic lymph nodes into n-hetero and n-homo groups. RESULTS: There were no significant differences between p-homo and p-hetero groups and between n-homo and n-hetero groups in prognosis. However, the recurrence-free survival rate of the n-homo group was significantly lower than that of the n-hetero group in the N2 category. CONCLUSION: Histological heterogeneity in metastatic lymph nodes may be useful for predicting prognosis, and prognosis in those with histological heterogeneity in a metastatic lymph node is not necessarily poor, even in those of the N2 category.

Macrophage colony-stimulating factor expressed in non-cancer tissues provides predictive powers for recurrence in hepatocellular carcinoma.

AIM: To investigate the role of macrophage colony-stimulating factor (M-CSF) in patients with hepatocellular carcinoma (HCC) after surgery. METHODS: Expression of M-CSF, distribution of M2 macrophages (MΦs), and angiogenesis were assessed in the liver, including tumors and peritumoral liver tissues. The prognostic power of these factors was assessed. Mouse isolated hepatic MΦs or monocytes were cultured with media containing M-CSF. The concentration of vascular endothelial growth factor (VEGF) in media was assessed. Furthermore, the role of the M-CSF-matured hepatic MΦs on proliferation of the vascular endothelial cell (VEC) was investigated. RESULTS: A strong correlation between the expressions of M-CSF and CD163 was observed in the peritumoral area. Also, groups with high density of M-CSF, CD163 or CD31 showed a significantly shorter time to recurrence (TTR) than low density groups. Multivariate analysis revealed the expression of M-CSF or hepatic M2MΦs in the peritumoral area as the most crucial factor responsible for shorter TTR. Moreover, the expression of M-CSF and hepatic M2MΦs in the peritumoral area had better predictable power of overall survival. Values of VEGF in culture media were significantly greater in the hepatic MΦs compared with the monocytes. Proliferation of the VEC was greatest in the cells co-cultured with hepatic MΦs when M-CSF was present in media. CONCLUSION: M-CSF increases hepatocarcinogenesis, most likely by enhancing an angiogenic factor derived from hepatic MΦ and could be a useful target for therapy against HCC.