Reconsideration of the Appropriate Dissection Range Based on Japanese Anatomical Classification for Resectable Pancreatic Head Cancer in the Era of Multimodal Treatment.

Patients with resectable pancreatic cancer are considered to already have micro-distant metastasis, because most of the recurrence patterns postoperatively are distant metastases. Multimodal treatment dramatically improves prognosis; thus, micro-distant metastasis is considered to be controlled by chemotherapy. The survival benefit of "regional lymph node dissection" for pancreatic head cancer remains unclear. We reviewed the literature that could be helpful in determining the appropriate resection range. Regional lymph nodes with no suspected metastases on preoperative imaging may become areas treated with preoperative and postoperative adjuvant chemotherapy. Many studies have reported that the R0 resection rate is associated with prognosis. Thus, "dissection to achieve R0 resection" is required. The recent development of high-quality computed tomography has made it possible to evaluate the extent of cancer infiltration. Therefore, it is possible to simulate the dissection range to achieve R0 resection preoperatively. However, it is often difficult to distinguish between areas of inflammatory changes and cancer infiltration during resection. Even if the "dissection to achieve R0 resection" range is simulated based on the computed tomography evaluation, it is difficult to identify the range intraoperatively. It is necessary to be aware of anatomical landmarks to determine the appropriate dissection range during surgery.

Causative bacteria associated with a clinically relevant postoperative pancreatic fistula infection after distal pancreatectomy.

PURPOSE: Clinically relevant postoperative pancreatic fistulas (CR-POPF) occurring after distal pancreatectomy often cause intra-abdominal infections. We monitored the presence of bacterial contamination in the ascitic fluid after distal pancreatectomy to clarify the bacterial origin of intra-abdominal infections associated with CR-POPF. METHODS: In 176 patients who underwent distal pancreatectomy, ascitic fluid bacterial cultures were performed on postoperative days (POD) 1-4 and when the drainage fluid became turbid. The association between postoperative ascitic bacterial contamination and CR-POPF incidence was investigated. RESULTS: CR-POPF occurred in 18 cases (10.2%). Among the patients with CR-POPF, bacterial contamination was detected in 0% on POD 1, in 38.9% on POD 4, and in 72.2% on the day (median, day 9.5) when the drainage fluid became turbid. A univariate analysis revealed a significant difference in ascitic bacterial contamination on POD 4 (p < 0.001) and amylase level on POD 3-4 (p < 0.001). A multivariate analysis revealed the amylase level and ascitic bacterial contamination on POD 4 to be independent risk factors. CONCLUSIONS: In the CR-POPF group, ascitic bacterial contamination was not observed in the early postoperative stage, but the bacterial contamination rate increased after pancreatic juice leakage occurred. Therefore, CR-POPF-related infections in distal pancreatectomy may be caused by a retrograde infection of pancreatic juice.

Preoperative cholangitis is associated with increased surgical site infection following pancreaticoduodenectomy.

BACKGROUND: Few reports describe the relationship between preoperative cholangitis and surgical site infections (SSIs) after pancreaticoduodenectomy (PD). We aimed to determine the association between the incidence of preoperative cholangitis and surgical site infection following PD. METHODS: The surgical outcomes of 359 patients who underwent PD were compared between patients with (n = 92) and without (n = 267) preoperative cholangitis. Bacterial cultures from the postoperative drainage fluid were examined. Risk factors for postoperative infectious complication were evaluated. RESULTS: The incidence of postoperative infectious complications including grade B/C postoperative pancreatic fistula was high among patients with preoperative cholangitis (P < .01). The positive rate of bacterial culture in the drainage fluid until postoperative day 3 (P < .01) and the detection rate of Enterococcus species (P < .01) were higher in the preoperative cholangitis group. The most common cause of preoperative cholangitis was drainage device dysfunction mainly with plastic stent occlusion. In the multivariate analysis, preoperative cholangitis (odds ratio 2.04, 95% confidence interval 1.13 to 3.69; P = .02) was an independent risk factor for postoperative infectious complications. CONCLUSIONS: Preoperative cholangitis significantly increased ascitic bacterial contamination and the incidence of postoperative infectious complications. after PD. Appropriate preoperative biliary drainage for the prevention of preoperative cholangitis is important for improving outcomes after PD.

Clinical impact of pancreaticoduodenectomy for pancreatic cancer with resection of the secondary or later branches of the superior mesenteric vein.

PURPOSE: To evaluate the feasibility of pancreaticoduodenectomy with resection of the second jejunal vein (J2V) for pancreatic ductal adenocarcinoma (PDAC). METHODS: Among 114 patients with PDAC undergoing pancreaticoduodenectomy with portal-superior mesenteric vein resection (PVR), surgical outcomes, and prognoses of 10 patients with resection of J2V or later branches of the superior mesenteric vein (J2VR) were compared to 104 patients with PVR above J2V (standard PVR). The reconstruction methods in the J2VR group were reviewed. RESULTS: There were no significant differences in the operative time (470 vs 435 min), morbidity (30% vs 27%), presence of portal vein stenosis (10% vs 5%) or thrombosis (10% vs 1%), and induction of adjuvant therapy (80% vs 88%) between the J2VR and standard PVR groups, although blood loss was higher in the J2VR group (1184 vs 494 ml; P = .002). R0 proportion and 2-year survival rates were not significantly worse in the J2VR group compared to the standard PVR group (90 and 88%; 67 and 45%, respectively). At least one branch of the superior mesenteric vein was reconstructed in the J2VR group. CONCLUSION: Pancreaticoduodenectomy with J2VR for PDAC can be safely performed with a satisfactory overall survival rate.

Blumgart method using LAPRA-TY clips facilitates pancreaticojejunostomy in laparoscopic pancreaticoduodenectomy.

The modified Blumgart method for pancreaticojejunostomy has been shown to reduce the rate of postoperative pancreatic fistula (POPF) in open surgery. We describe a modified Blumgart method using LAPRA-TY suture clips to facilitate laparoscopic pancreaticojejunostomy.We prepared a double-armed 4-0 nonabsorbable monofilament, which was ligated using the LAPRA-TY clip at the tail end, 12-cm in length. Next, the U-suture was placed through the pancreatic stump and the seromuscular layer of the jejunum. We performed duct-to-mucosa suturing with a 5-0 absorbable monofilament. After completing the duct-to-mucosa suturing, as a final step we placed the sutures through the seromuscular layer of the jejunum on the ventral side and tightly secured the thread with the LAPRA-TY clips. We performed laparoscopic Blumgart pancreaticojejunostomy during pancreaticoduodenectomy in 39 patients. We compared the surgical outcomes of 19 patients who underwent Blumgart pancreaticojejunostomy using the LAPRA-TY clips (LAPRA-TY group) with 20 patients undergoing surgery not using the LAPRA-TY clips (conventional group).The rate of clinically relevant postoperative pancreatic fistula in the LAPRA-TY group was 21.1%, which did not differ significantly from the rate of the conventional group. However, the mean time of pancreaticojejunostomy in the LAPRA-TY group was 56.2 min (range, 39-79 min), which was significantly shorter than that of the conventional group (69.7 min; range, 53-105 min, P < .001).Although the modified Blumgart pancreaticojejunostomy using LAPRA-TY suture clips did not improve the pancreatic fistula rate, it allowed for shorter operative times. Thus, this procedure lends itself to positive surgical and patient outcomes.

Growth of single-crystalline Bi2Te3 hexagonal nanoplates with and without single nanopores during temperature-controlled solvothermal synthesis.

Bismuth telluride (Bi2Te3) is a promising thermoelectric material for applications near room temperature. To increase the thermoelectric performance of this material, its dimensions and thermal transport should be decreased. Two-dimensional nanoplates with nanopores are an ideal structure because thermal transport is disrupted by nanopores. We prepared Bi2Te3 nanoplates with single nanopores by a solvothermal synthesis and investigated their structural and crystallographic properties. The nanoplates synthesized at a lower reaction temperature (190 °C) developed single nanopores (approximately 20 nm in diameter), whereas the nanoplates synthesized at a higher reaction temperature (200 °C) did not have nanopores. A crystal growth mechanism is proposed based on the experimental observations.

Clinical Impact of Neoadjuvant Chemotherapy and Chemoradiotherapy in Borderline Resectable Pancreatic Cancer: Analysis of 884 Patients at Facilities Specializing in Pancreatic Surgery.

BACKGROUND: The efficacy of neoadjuvant therapy (NAT), including neoadjuvant chemotherapy (NAC) and neoadjuvant chemo-radiotherapy (NACRT), for patients with borderline resectable pancreatic cancer (BRPC) has not been elucidated. This study aimed to clarify the efficacy of NAC and NACRT for patients with BRPC. METHODS: The study analyzed the treatment outcomes of 884 patients treated for BRPC from 2011 to 2013. Treatment results were compared between upfront surgery and NAT and between NAC and NACRT using propensity score-matching analysis. Overall survival (OS) was calculated via intention-to-treat analyses. RESULTS: The overall resection rates for the patients who underwent NAT were significantly lower than for the patients who underwent upfront surgery (75.1% vs 93.3%; p < 0.001). However, the R0 resection rate was significantly higher for NAT than for upfront surgery (p < 0.001). Additionally, the OS for the patients who received NAT was significantly longer than for those who underwent upfront surgery (median survival time [MST], 25.7 vs 19.0 months; p = 0.015). The lymph node rate for the patients with NACRT was significantly lower than for those who underwent NAC (p < 0.001). However, the resection rate for the NACRT cases was significantly lower than for the NAC cases (p = 0.041). The local recurrence rate for the NACRT cases was significantly lower than for the NAC cases (p = 0.002). However, OS did not differ significantly between NAC and NACRT (MST, 29.2 vs 22.5 months; p = 0.130). CONCLUSIONS: The study showed that NAT has potential benefit for patients with BRPC. Compared with NAC, NACRT decreased the rates for lymph node metastasis and local recurrence but did not improve the prognosis.

Why Does Postoperative Pancreatic Fistula Occur After Hand-sewn Parenchymal Closure and Staple Closure in Distal Pancreatectomy?

Hand-sewing (HS) and stapling are common parenchymal closure techniques after distal pancreatectomy. However, these methods cannot completely prevent postoperative pancreatic fistula (POPF). The mechanisms of POPF formation after closure are unknown. We performed distal pancreatectomy in mongrel dogs to identify the mechanisms of POPF formation after HS and staple closure. We measured the closed pancreatic duct burst pressures and examined the histology of the remnant pancreas. The after staple-closure burst pressures depended on stapler height; lower pressures were associated with greater stapler heights. Post-HS closure burst pressures were significantly higher than those at each stapler height (P<0.01). Post-HS closure pathologic findings showed extensive necrosis (day 3), and some regenerated pancreatic duct stumps (day 5). Necrosis was not observed around the stapled tissues. Although HS completely closes the pancreatic ducts, stump necrosis and blood flow disturbances may cause POPF. With stapler closure, pancreatic fluid leakage may occur even with appropriate stapler heights.

Irreversible Electroporation for Nonthermal Tumor Ablation in Patients with Locally Advanced Pancreatic Cancer: Initial Clinical Experience in Japan.

Objective To evaluate irreversible electroporation (IRE) for locally advanced pancreatic cancer (LAPC). Methods This study was approved by our local review board. Eight patients with histologically proven LAPC ≤5 cm were prospectively enrolled to undergo ultrasound-guided IRE. The primary endpoint was complications within 90 days. Secondary outcomes were the overall survival (OS) and time to local progression. Safety was assessed using Common Terminology Criteria for Adverse Events Version 4.0. Results All patients were treated successfully. The median procedure time was 150 min. The median largest tumor diameter was 29.5 mm (20.0-48.0 mm) in the pancreatic head (n=5) and body (n=3). Open (n=4) and percutaneous (n=4) approaches were used. No patients died within 90 days after IRE. There were 5 minor complications in 3 patients and 4 major complications in 3 patients. The incidence rates of major complications did not differ significantly between the approaches. The median time to local progression after IRE was 12.0 months, and the median OS was 17.5 months from IRE and 24.0 months from the diagnosis, with no significant differences between the approaches. Conclusions Percutaneous and open IRE may be acceptable for patients with LAPC (despite some major adverse events) and may represent a useful new therapeutic option.

Surgical resection of neuroendocrine tumors of the pancreas (pNETs) by minimally invasive surgery: the laparoscopic approach.

Neuroendocrine tumors of the pancreas (pNETs) are a rare group of neoplasms that originate from the endocrine portion of the pancreas. Tumors that either secrete or do not secrete compounds, resulting in symptoms, can be classified as functioning and non-functioning pNETs, respectively. The prevalence of such tumors has recently increased due to the use of more sensitive imaging techniques, such as multidetector computed tomography, magnetic resonance imaging and endoscopic ultrasound. The biological behavior of pNETs varies widely from indolent, well-differentiated tumors to those that are far more aggressive. The most effective and radical treatment for pNETs is surgical resection. Over the last decade, minimally invasive surgery has been increasingly used in pancreatectomy, with laparoscopic pancreatic surgery (LPS) emerging as an alternative to open pancreatic surgery (OPS) in patients with pNETs. Non-comparative studies have shown that LPS is safe and effective. In well-selected groups of patients with pancreatic lesions, LPS was found to results in good perioperative outcomes, including reduced intraoperative blood loss, postoperative pain, time to recovery, and length of hospital stay. Despite the encouraging results of studies from highly specialized centers with extensive experience, no randomized trials to date have conclusively validated these findings. Indications for minimally invasive LPS for patients with pNETs remain unclear. This review presents the current state of LPS for pNETs.

Surgical Outcomes of Pancreaticoduodenectomy for Pancreatic Cancer with Proximal Dorsal Jejunal Vein Involvement.

BACKGROUND/PURPOSE: The proximal jejunal vein which branches from the dorsal side of the superior mesenteric vein (SMV) usually drains the inferior pancreatoduodenal veins (IPDVs) and contacts the uncinate process of the pancreas. We focused on this vein, termed the proximal dorsal jejunal vein (PDJV), and evaluated the anatomical classification of the PDJV and surgical outcomes in patients with pancreatic ductal adenocarcinoma (PDAC) with PDJV involvement (PDJVI). METHODS: The jejunal veins that branch from the dorsal side of the SMV above the inferior border of the duodenum are defined as PDJVs. We investigated 121 patients who underwent upfront pancreaticoduodenectomy for PDAC between 2011 and 2017; PDJVs were resected in all patients. The anatomical classification of PDJV was evaluated using multidetector computed tomography. Surgical and prognostic outcomes of pancreticoduodenectomy for PDAC with PDJVI were evaluated. RESULTS: The PDJVs were classified into seven types depending on the position of the first and second jejunal veins relative to the superior mesenteric artery. In all patients, the morbidity and mortality rates were 15.7 and 0.8%, respectively. The rates for parameters including SMV resection, presence of pathological T3-4, R0 resection, and 3-year survival were 46.2, 92.3, 92.3, and 61.1%, respectively, when there was PDJVI (n = 13). When there was no PDJVI (n = 108), the rates were 60.2, 93.5, 86.1, and 58.3%, respectively. Overall, there were no significant differences. CONCLUSIONS: Pancreaticoduodenectomy with PDJV resection is feasible for PDAC with PDJVI and satisfactory overall survival rates are achievable. It may be necessary to reconsider the resectability of PDAC with PDJVI.

Approaching the superior mesenteric artery from the right side using the proximal-dorsal jejunal vein preisolation method during laparoscopic pancreaticoduodenectomy.

BACKGROUND: Although the artery-first approach is widely used in open pancreaticoduodenectomy, it is difficult to laparoscopically expose the origin of the inferior pancreaticoduodenal artery (IPDA) from the left side of the superior mesenteric artery (SMA). By contrast, damaging the inferior pancreaticoduodenal veins (IPDVs) is possible when approaching the IPDA from the right side of the SMA. To facilitate the artery-first approach in laparoscopic pancreaticoduodenectomy (LPD), we focused on the proximal-dorsal jejunal vein (PDJV) that branched from the superior mesenteric vein (SMV) dorsal side and drained the IPDVs. This study aimed to clarify the usefulness of the right SMA approach using the PDJV preisolation method. METHODS: The PDJV was first isolated, and the IPDVs were divided along the PDJV on the right side of the SMA. Then, the IPDA was divided at the root without first separating the pancreatic head from the portal vein and the SMV. Overall, 21 patients underwent this approach, and the results were retrospectively compared with those of 21 patients who underwent the artery-first approach, which was performed on the left side of the SMA. Anatomical characteristics of the PDJV were evaluated using multidetector computed tomography for the two groups. RESULTS: Operative times and resection times were significantly lower for the PDJV preisolation group than for the conventional LPD group (489.3 vs. 541.7 min, respectively; p = 0.002). During anatomical evaluation, 41 patients (97.6%) had a PDJV that drained from the SMV dorsally and was in contact with the anterior aspect of the uncinate process. The PDJV was confirmed as the first jejunal vein in 31 patients (73.8%) and as the second jejunal vein in 10 patients (23.8%). CONCLUSIONS: This approach facilitates dissection of the IPDA on the right side of the SMA, thereby reducing operative times.

Liver metastasis is established by metastasis of micro cell aggregates but not single cells.

Cancer cell engraftment in the target organ is necessary to establish metastasis. Clinically, lymph node metastasis of single cells has been confirmed using cytokeratin staining. In the current study, a LacZ-labeled cancer cell line was used to visualize intrahepatic metastasis of single cells or liver micrometastasis. KM12SM-lacZ stably expressing LacZ was prepared with a highly metastatic colon cancer cell line, KM12SM. KM12SM-lacZ was injected into the spleen of nude mice and following 1 week the spleen was excised. The liver was then examined for metastasis following 1, 2 or 3 weeks. Confirmation of liver metastasis was completed by observing the grade of metastasis. Grade-1 metastasis (DNA level), human DNA in liver tissue was detected; Grade-2 metastasis (metastasis of single cells), confirmed by X-gal staining; Grade-3 metastasis (histopathological micrometastasis), diagnosed by light microscopy and Grade-4 metastasis (typical metastasis), easily detected macroscopically or by hematoxylin and eosin staining. The Grade-1 metastasis detection rates 1, 2 and 3 weeks following splenectomy were 50, 100 and 100%, respectively. Grade-2 metastasis was not detected by microscopy. The Grade-3 metastasis detection rates for 1, 2 and 3 weeks were 75, 100 and 100%, respectively. Micrometastasis was observed in the portal vein lumen and wall. The Grade-4 metastasis detection rates were 50, 100 and 100% for 1, 2 and 3 weeks respectively. Cancer cells were present in vessels surrounding the main tumor. In conclusion, a specific number of cancer cell aggregates may be necessary to establish hematogenous metastasis.

A phase II trial of neoadjuvant chemoradiotherapy with intensity-modulated radiotherapy combined with gemcitabine and S-1 for borderline-resectable pancreatic cancer with arterial involvement.

PURPOSE: Chemoradiotherapy using intensity-modulated radiotherapy (IMRT) is expected to provide a powerful alternative to conventional chemotherapy with a low incidence of adverse events. This study evaluated the efficacy of intensity modulated radiotherapy in combination with gemcitabine and S-1 as neoadjuvant chemoradiotherapy (NACRT) for borderline-resectable pancreatic cancer with arterial involvement (BR-A). METHODS: A total of 27 patients with BR-A were enrolled in this study between February 2012 and September 2015. IMRT was administered at 50.4 Gy in 28 fractions with concurrent gemcitabine at a dose of 600 mg/m2 and S-1 at a dose of 60 mg. RESULTS: Only one patient (3.5%) experienced gastrointestinal adverse events at grade 3 or higher. Nineteen patients (70.3%) underwent resection, and R0 resection was achieved in 18 patients (94.7%). Thirteen patients (68.4%) developed distant metastasis at the initial site of recurrence after resection. Local recurrence developed in only one of these patients (7.7%). The median overall survival and 1-year survival rates were 22.4 months and 81.3%, respectively. CONCLUSIONS: Concurrent IMRT with gemcitabine and S-1 for patients is feasible as NACRT for BR-A with low gastrointestinal toxicity. IMRT can be employed as a standard radiotherapy to provide more effective NACRT with powerful chemotherapy drugs.

The Straightened Splenic Vessels Method Improves Surgical Outcomes of Laparoscopic Distal Pancreatectomy.

BACKGROUND: In laparoscopic distal pancreatectomy (LDP), isolating the splenic artery and vein requires advanced techniques. This study aimed to assess the efficacy of a novel method termed the 'straightened splenic vessels' (SSV) method for isolating the splenic vessels in LDP. METHODS: In SSV, to adjust the instrument axis, the splenic artery was straightened by grasping 2 points of its nerve sheath. Then, the layer between the splenic artery's nerve sheath and the pancreatic parenchyma was dissected. Next, the pancreas was mobilized from body to tail, and the splenic vein was straightened by 3-point retraction before isolation. To evaluate this method's efficacy, we investigated 51 patients who underwent LDP. RESULTS: In 39 patients who underwent LDP with splenectomy, the mean operating time was significantly shorter in the SSV group than in the conventional group (p = 0.004). In 12 patients who underwent LDP with preserving the splenic vessels, the mean intraoperative blood loss in the SSV group was 27.6 ml, which was significantly lower than that in the conventional group (p = 0.012). CONCLUSION: This method may be applied as a standard procedure with little blood loss and short operation time for LDP. Larger prospective studies are needed to further evaluate the feasibility.

Serum SPan-1 Is a Significant Risk Factor for Early Recurrence of Pancreatic Cancer after Curative Resection.

BACKGROUND/AIMS: Curative resection is still the only treatment for patients with pancreatic ductal adenocarcinoma (PDAC). However, early postoperative recurrence occurs frequently. The aim of this study was to investigate the predictors of early recurrence of PDAC. METHODS: Clinical data of 172 consecutive patients with PDAC who underwent curative resection (R0) between 2000 and 2015 at Tokyo Medical University Hospital were retrospectively analyzed. RESULTS: The median follow-up period was 18.2 months. Recurrence occurred in 96 of 172 (55.8%) patients, 27 in whom recurrence occurred within 6 months (early recurrence). Median survival time of the early recurrence group was 10.7 months. The optimal cutoff concentrations for the prediction of early recurrence were 111.3 U/ml, 3.0 ng/ml, 41 U/ml and 670 U/ml for CA19-9, carcinoembryonic antigen, SPan-1 and DUPAN-2, respectively. Multivariate analysis demonstrated that a SPan-1 concentration of >41 U/ml, having received neoadjuvant therapy and having never received adjuvant chemotherapy were significant and independent predictors of early recurrence. CONCLUSION: A preoperative SPan-1 concentration of >41 U/ml is a significant and independent predictor of the early recurrence of pancreatic adenocarcinoma.

RhoA activity increases due to hypermethylation of ARHGAP28 in a highly liver-metastatic colon cancer cell line.

Certain cell lines exhibit metastatic ability (highly metastatic cell lines) while their parent cell lines have no metastatic ability. Differences in methylation, which are not derived from differences in the gene sequence between cell lines, were extensively analyzed. Using an established highly metastatic cell line, KM12SM, and its parent cell line, KM12C, differences in the frequency of methylation were analyzed in the promoter regions of ~480,000 gene sites using Infinium HumanMethylation450. The promoter region of the Rho GTPase-activating protein 28 (ARHGAP28) gene was the most markedly methylated region in KM12SM compared with KM12C. ARHGAP28 is a GTPase-activating protein (GAP), and it converts activated RhoA to inactivated RhoA via GTPase. RhoA activity was compared between these two cell lines. The activated RhoA level was compared using western blot analysis and G-LISA. The activated RhoA level was higher in KM12SM compared to KM12C for western blot analysis and G-LISA analysis. RhoA is a protein involved in cytoskeleton formation and cell motility. RhoA, for which ARHGAP28 acts as a GAP, is possibly a factor involved in the metastatic ability of cancer.

Feasibility of intensity-modulated radiotherapy combined with gemcitabine and S-1 for patients with pancreatic cancer.

The aim of the present study was to establish whether intensity-modulated radiotherapy (IMRT) with concurrent gemcitabine and S-1 is a feasible treatment option for patients with locally advanced pancreatic ductal adenocarcinoma. Patients with pancreatic ductal adenocarcinoma were prospectively enrolled. An IMRT dose of 50.4 Gy in 28 fractions with concurrent gemcitabine at a dose of 600 mg/m2 and S-1 at a dose of 60 mg were administrated. Adverse events and associated dosimetric factors were assessed. Between February 2012 and January 2014, 17 patients with borderline resectable and 4 with unresectable pancreatic cancer were enrolled. None of the patients experienced grade 3 or worse nausea and vomiting. The planning target volume (≥200 vs. <200 ml) was a statistically significant predictive factor for neutrocytopenia (≥500 vs. 500/µl, P=0.02). Concurrent IMRT with gemcitabine and S-1 for patients with locally advanced pancreatic cancer is feasible, with tolerable hematological toxicities and low gastrointestinal toxicities.

Laparoscopic distal pancreatectomy without needle aspiration before resection for giant mucinous cell neoplasms.

Laparoscopic resection of large mucinous cystic neoplasms (MCN) has recently been reported. However, in most reports, needle aspiration of the cyst contents was performed before resection and can cause dissemination. Here, we report two patients with giant MCN: a 26-year-old woman with a 23-cm MCN and a 41-year-old woman with an 18-cm MCN. The MCN were successfully resected without aspiration by laparoscopic surgery. CT revealed no tumor involvement of the origins of the splenic artery and vein in either case. In case 1, we performed hand-assisted laparoscopic surgery while dissecting around the spleen, whereas case 2 underwent pure laparoscopic surgery. No postoperative complications occurred in either case, indicating that laparoscopic distal pancreatectomy for giant MCN is feasible without aspiration in patients without splenic artery and vein origin involvement.

[A Large Number of Circulating Tumor Cells(CTCs)Can Be Isolated from Samples Obtained by Using Leukapheresis Procedures].

We hypothesized that a large number of circulating tumor cells(CTCs)may be isolated from samples obtained by using the leukapheresis procedures that are utilized to collect peripheral blood mononuclear cells for dendritic cell vaccine therapy. We utilized the CellSearch System to determine the number of CTCs in samples obtained by using leukapheresis in 7 patients with colorectal cancer, 5 patients with breast cancer, and 3 patients with gastric cancer. In all patients, a large number of CTCs were isolated. The mean number of CTCs per tumor was 17.1(range 10-34)in colorectal cancer, 10.0(range 2-27)in breast cancer, and 24.0(range 2-42)in gastric cancer. We succeeded in culturing the isolated CTCs from 7 patients with colorectal cancer, 5 patients with breast cancer, and 3 patients with gastric cancer. In conclusion, compared to conventional methods, a large number of CTCs can be obtained by using leukapheresis procedures. The molecular analyses of the CTCs isolated by using this method should be promising in the development of personalized cancer treatments.