Resection of a retroperitoneal lumbar vein aneurysm: A case report.

We present a rare case involving a 54-year-old man with a history of pancreatitis who developed a retroperitoneal lumbar vein aneurysm that was initially misidentified as a pancreatic pseudocyst. Subsequent imaging revealed an enlarged mass and retroperitoneal perforation. Despite initial hesitation, the patient eventually underwent radical surgery that enabled the successful removal of the mass, which was near the inferior vena cava. Pathological examination confirmed varicose veins, and the final diagnosis was lumbar vein aneurysm in the retroperitoneum. The patient's postoperative recovery was uneventful, with no symptoms or recurrence observed on 6-month follow-up imaging. We investigated a potential link between pancreatitis and recurrent bleeding due to weakened venous walls. The findings from this case underscore the rarity of venous aneurysms and the diagnostic and treatment challenges due to the limited number of cases; furthermore, they emphasize that surgery should be carefully considered based on the lesion location and associated risks.

Efficacy and safety of postoperative preemptive use of tolvaptan for patients with cirrhosis undergoing hepatectomy for hepatocellular carcinoma.

PURPOSE: Optimal choice of diuretics in perioperative management remains unclear in enhanced recovery after liver surgery. This study investigated the efficacy and safety of tolvaptan (oral vasopressin V2-receptor antagonist) in postoperative management of patients with liver injury and hepatocellular carcinoma. METHODS: The patients clinically diagnosed with liver cirrhosis were included in this study. Clinical outcomes of 51 prospective cohort managed with a modified postoperative protocol using tolvaptan (validation group) were compared with 83 patients treated with a conventional management protocol (control group). RESULTS: Postoperative urine output were significantly larger and excessive body weight increase were reduced with no impairment in renal function or serum sodium levels in the validation group. Although the total amount of discharge and trend of serum albumin level were not significantly different among the groups, global incidence of postoperative morbidity was less frequent (19.6% vs. 44.6%, P=0.005) and postoperative stay was significantly shorter (8 days vs.10 days, P=0.008) in the validation group compared with the control group. CONCLUSIONS: Tolvaptan could be safely used for the patients with injured liver in postoperative management after hepatectomy and potentially advantageous in the era of enhanced recovery after surgery with its strong diuretic effect and better fluid management.

Efficacy of the Combination of Systemic Sequential Therapy and Locoregional Therapy in the Long-Term Survival of Patients with BCLC Stage C Hepatocellular Carcinoma.

BACKGROUND: The aim of this study was to evaluate the clinical impact of a combination of systemic sequential therapy and locoregional therapy on the long-term survival of patients with Barcelona Clinic Liver Cancer (BCLC) stage C hepatocellular carcinoma (HCC). METHODS: Sixty-four consecutive patients with intrahepatic target nodules who had initially received systemic therapy (lenvatinib and atezolizumab plus bevacizumab) were reviewed. The clinical impact of the combined use of systemic sequential therapy and locoregional therapy was evaluated by determining overall survival (OS). The combined use of systemic sequential therapy with more than two agents and locoregional treatment was defined as multidisciplinary combination therapy (MCT), while only systemic sequential therapy and repeated locoregional-treatment was defined as a single treatment procedure (STP). RESULTS: R0 resection, MCT, and STP resulted in significantly better OS compared with no additional treatment (median OS, not reached vs. 18.2 months and 12.6 vs. 8.1 months, respectively; p = 0.002). Multivariate analysis confirmed that the use of R0 resection and MCT were associated with better OS (hazard ratio [HR]; 0.053, p = 0.006 and 0.189, p < 0.001, respectively) compared with that for STP (HR; 0.279, p = 0.003). CONCLUSIONS: MCT is may effective in patients with BCLC stage C HCC and intrahepatic target nodules who have previously received systemic therapy-based treatment.

Total pancreatectomy with remnant stomach preservation in a patient with a history of proximal gastrectomy and interposed jejunal reconstruction with right gastroepiploic conduit preservation: a case report.

BACKGROUND: Pancreatic head resection following proximal gastrectomy jeopardizes the blood flow of the remnant stomach owing to right gastroepiploic conduit sacrifice, thereby necessitating total gastrectomy. However, owing to its high invasiveness, concomitant remnant total gastrectomy with pancreatectomy should be avoided as much as possible. Herein, we describe our experience of total pancreatectomy with right gastroepiploic conduit preservation in a patient with a history of proximal gastrectomy and reconstruction by jejunum interposition. CASE PRESENTATION: A 78-year-old woman with a history of gastric cancer was followed up at our institute for multiple intraductal papillary mucinous neoplasm, and main pancreatic duct stricture in the pancreatic head was newly detected. The cystic lesion was extended to the pancreatic body. Proximal gastrectomy and reconstruction by jejunal interposition were previously performed, and the mesenteric stalk of the interposed jejunum was approached through the retrocolic route. We planned total pancreatectomy with right gastroepiploic conduit preservation. Following adhesiolysis, the interposed jejunum and its mesentery lying in front of the pancreas were isolated. The arterial arcade from the common hepatic artery to the right gastroepiploic artery was detached from the pancreas. Furthermore, the right gastroepiploic vein was isolated from the pancreas. The pancreatic body and tail were pulled up in front of the remnant stomach, and the splenic artery and vein were resected. The pancreatic body and tail were pulled out to the right side, and the pancreatic head was divided from the pancreatic nerve plexus to the portal vein. The jejunal limb for entero-biliary anastomosis was passed through the hole behind the superior mesenteric artery and vein, and gastrointestinal anastomosis using the antecolic route and Braun anastomosis were performed. CONCLUSIONS: To avoid remnant total gastrectomy, right gastroepiploic conduit preservation is an optional procedure for pancreatic head resection in patients who have undergone proximal gastrectomy with reconstruction by jejunal interposition.

Annual report on National Clinical Database 2020 for gastroenterological surgery in Japan.

Aim: The National Clinical Database (NCD) of Japan is a nationwide data entry system for surgery, and it marked its 10th anniversary in 2020. The aim was to present the 2020 annual report of gastroenterological surgery of the NCD. Methods: The data of the surgical procedures stipulated by the training curriculum for board-certified surgeons of the Japanese Society of Gastroenterological Surgery in the NCD from 2011 to 2020 were summarized. Results: In total, 5 622 845 cases, including 593 088 cases in 2020, were extracted from the NCD. The total number of gastroenterological surgeries increased gradually in these 10 years, except for the year 2020 due to the COVID-19 pandemic. The annual number of surgeries of each organ, except the pancreas and liver, decreased by 0.4%-13.1% in 2020 compared to 2019. The surgical patients were consistently aging, with more than 20% of all gastroenterological surgeries in 2020 involving patients aged 80 years or older. The participation of board-certified surgeons increased for each organ (75.9%-95.7% in 2020). The rates of endoscopic surgery also increased constantly. Although the incidences of postoperative complications of each organ increased by 0.7%-7.9% in these 10 years, postoperative mortality rates decreased by 0.2%-1.5%. Conclusions: We present here the short-term outcomes of each gastroenterological operative procedure in 2020. This review of the 10-years of NCD data of gastroenterological surgery revealed a consistent increase of the number of surgeries (except for in 2020), especially endoscopic procedures, and aging of the Japanese population. The good safety of Japanese gastroenterological surgeries was also indicated.

Disease-Free Interval and Tumor Stage Complementarily Predict the Biological Behavior of Recurrent Hepatocellular Carcinoma.

BACKGROUND: Currently used treatment algorithms were originally established based on the clinical outcomes of the initial treatment for primary hepatocellular carcinoma (HCC), and no strong evidence exists yet to suggest if these algorithms could also be applicable to patients with recurrent HCC after surgery. As such, this study sought to explore an optimal risk stratification method for cases of recurrent HCC for better clinical management. METHODS: Among the 1616 patients who underwent curative resection for HCC, the clinical features and survival outcomes of 983 patients who developed recurrence were examined in detail. RESULTS: Multivariate analysis confirmed that both the disease-free interval (DFI) from the previous surgery and tumor stage at recurrence were significant prognostic factors. However, the prognostic impact of DFI seemed different according to the tumor stages at recurrence. While curative-intent treatment showed strong influence on survival [hazard ratio (HR), 0.61; P < 0.001] regardless of the DFI in patients with stage 0 or stage A disease at recurrence, early recurrence (< 6 months) was a poor prognostic marker in patients with stage B disease. The prognosis of patients with stage C disease was exclusively influenced by the tumor distribution or choice of treatment than by the DFI. CONCLUSIONS: The DFI complementarily predicts the oncological behavior of recurrent HCC, with its predictive value differing depending on the tumor stage at recurrence. These factors should be considered for selection of the optimal treatment in patients with recurrent HCC after curative-intent surgery.

Subserosal vascular density predicts oncological features of T2 gallbladder cancer.

PURPOSE: Tumor sidedness (hepatic side vs. peritoneal side) reportedly predicts microvascular invasion and survival outcomes of T2 gallbladder cancer, although the actual histopathological mechanism is not fully understood. METHODS: The clinical relevance of tumor sidedness was revisited in 84 patients with gallbladder cancer using histopathological analysis of the vascular density of the gallbladder wall. RESULTS: Hepatic-side tumor location was associated with overall survival (OS) (hazard ratio [HR], 13.62; 95% confidence interval [CI], 2.09-88.93) and recurrence-free survival (RFS) (HR, 8.70; 95% CI, 1.36-55.69) in T2 tumors. The Adjusted Kaplan-Meier curve indicated a clear survival difference between T2a (peritoneal side) and T2b (hepatic side) tumors (P = 0.006). A review of 56 pathological specimens with gallbladder cancer and 20 control specimens demonstrated that subserosal vascular density was significantly higher on the hepatic side of the gallbladder, regardless of the presence of cancer (P < 0.001). Multivariate analysis also confirmed that higher subserosal vascular density was significantly associated with poor OS (HR, 1.73; 95% CI, 1.10-2.73 per 10 microscopic fields) and poor RFS (HR, 1.62; 95% CI, 1.06-2.49) in T2  gallbladder cancer. CONCLUSION: Higher subserosal vascular density may account for the higher incidence of cancer spread and the poor prognosis of T2b gallbladder cancer.

A preoperative risk score based on multifrequency bioelectrical impedance analysis in patients undergoing liver resection.

PURPOSE: To investigate if body composition parameters measured by bioelectrical impedance analysis (BIA) and are reportedly correlated with clinical outcomes of patients undergoing digestive tract surgery could be useful for reliably evaluating the perioperative risk in patients undergoing hepatectomy. METHODS: Consecutive 200 patients who underwent BIA before hepatectomy were retrospectively reviewed. A risk prediction model for postoperative morbidity was created using the initial 100 patients, and its performance was validated using the remaining 100 patients. RESULTS: Based on the correlation with postoperative morbidity, a novel risk prediction model, the protein-edema score, was created using net protein weight and extracellular water/total body water ratio measured through BIA. The protein-edema score (score 0 vs. ≥ 1) showed a reproducible correlation with Clavien-Dindo 2 or greater postoperative morbidity in the validation set (17.7% vs. 46.4%, P = 0.002) as observed in the training set (18.8% vs. 49.0%, P = 0.002) after statistical adjustment. Similar tendency was also confirmed in Clavien-Dindo 3a or greater postoperative morbidity (5.9% vs. 18.2%, P = 0.037) and postoperative refractory ascites (5.5% vs. 17.4%, P = 0.037) in the validation set. CONCLUSIONS: The protein-edema score created based on BIA is significantly correlated with postoperative morbidity in patients undergoing liver resection.

Risk Stratification of Patients with Marginal Hepatic Functional Reserve Using the Remnant Hepatocyte Uptake Index in Gadoxetic Acid-Enhanced Magnetic Resonance Imaging for Safe Liver Surgery.

BACKGROUND: This study aimed to explore the efficacy of gadoxetic acid-enhanced (Gd-EOB) magnetic resonance imaging (MRI) in surgical risk estimation among patients with marginal hepatic function estimated by indocyanine green (ICG) clearance test. METHODS: This analysis focused on 120 patients with marginal hepatic functional reserve (ICG clearance rate of future liver remnant [ICG-Krem] < 0.10). Preoperative Gd-EOB MRI was retrospectively reviewed, and the remnant hepatocyte uptake index (rHUI) was calculated for quantitative measurement of liver function. The predictive power of rHUI for posthepatectomy liver failure was compared with several clinical measures used in current risk estimation before hepatectomy. RESULTS: Receiver operating curve analysis showed that rHUI had the best predictive power for posthepatectomy liver failure among the tested variables (ICG-R15, ICG-Krem, albumin + bilirubin score, and albumin + ICG-R15 score). Cross-validation showed that a threshold of 925 could be the best cut-off value for estimating the postoperative risk of liver failure with sensitivity, specificity, positive likelihood ratio, and negative likelihood ratio of 0.689, 0.884, 5.94, and 0.352, respectively. CONCLUSION: rHUI could be a sensitive substitute measure for posthepatectomy liver failure risk estimation among patients with marginal hepatic functional reserve.

Well-preserved liver function enhances the clinical impact of curative-intent subsequent treatment during lenvatinib treatment for unresectable hepatocellular carcinoma.

BACKGROUND: The aims of this study were to evaluate the clinical impact of curative-intent subsequent treatment on overall prognosis in lenvatinib-treated hepatocellular carcinoma (HCC) patients. METHODS: Eighty-three consecutive patients with intrahepatic target nodules who received lenvatinib were reviewed. The clinical impact of curative-intent subsequent treatments was investigated through analysis of overall survival (OS) according to pathological deterioration stratified by mALBI grade. RESULTS: In patients with mALBI grade 1 and 2a liver function, R0 resection and lenvatinib-transarterial chemoembolization (lenvatinib-TACE) sequential therapy resulted in significantly better OS compared with other, non-curative-intent subsequent therapy and lack of additional treatment (median OS, 37.6 vs 29.0 months and 17.1 vs 8.9 months, respectively; P < 0.001). Multivariate analysis confirmed that use of R0 resection and lenvatinib-TACE sequential therapy were associated with better OS (hazard ratio [HR], 0.021; P < 0.001 and 0.108; P < 0.001) compared with other, non-curative-intent subsequent treatment (HR 0.256; P = 0.010). In contrast, in patients with mALBI grade 2b liver function, multivariate analysis confirmed higher treatment efficacy for non-curative-intent subsequent treatment with respect to OS (HR 0.041; P < 0.001) compared with R0 resection and lenvatinib-TACE sequential therapy (HR 0.057; P = 0.027 and 0.063; P = 0.001). CONCLUSION: Curative-intent subsequent treatment is more useful for HCC patients with better liver function (mALBI grade 1 and 2a) and intrahepatic target nodules who have received lenvatini b-based treatment.

The Impact of Lenvatinib on Tumor Blood Vessel Shrinkage of Hepatocellular Carcinoma during Treatment: An Imaging-Based Analysis.

INTRODUCTION: When lenvatinib is administered to people with hepatocellular carcinoma (HCC), tumor blood flow is reduced due to the inhibition of the vascular endothelial growth factor receptor (VEGFR) and fibroblast growth factor receptor (FGFR). Few studies have examined the decrease in tumor blood flow with respect to changes in tumor blood vessels (TBVs) in clinical practice. We investigated the mechanism of tumor blood flow control by investigating changes in the diameter of relatively large TBVs in large-sized lesions with high blood flow. METHODS: From January 2011 to October 2021, patients receiving lenvatinib for unresectable intrahepatic HCC at Toranomon Hospital, Tokyo, Japan, were considered for inclusion. We investigated the TBV diameter in the arterial phase of dynamic computed tomography before treatment and its change over time (2-12 weeks after lenvatinib initiation). The relationship between changes in TBV diameter and prognosis was also examined. RESULTS: Of 114 patients treated with lenvatinib for HCC, 26 patients who had intrahepatic lesions with a tumor diameter of 30 mm or more enrolled in the study. The median tumor and TBV diameters before treatment were 58 mm and 2.55 mm, respectively. Twenty-five patients (96%) had a shrinkage in TBV diameter 2-12 weeks after lenvatinib administration. The maximum TBV diameter shrinkage of 20% or more was observed in 19 patients (73%), and progression-free survival was prolonged in these patients compared to the group with less than 20% TBV diameter shrinkage (p = 0.039). DISCUSSION/CONCLUSION: Due to the antiangiogenic effect of lenvatinib, a shrinkage in the TBV diameter of HCC was observed. The shrinkage of TBV may be regarded as a process of normalization of TBVs. The shrinkage of TBVs in imaging analysis may be associated with improved prognosis; however, additional studies are still required.

Gallbladder cancer concomitant with autosomal dominant polycystic kidney disease: A case report.

The case is a 67-year-old female with autosomal dominant polycystic kidney disease who was followed up regularly. CT scan showed a mural nodule growing over the past 4 years inside the hypodense region surrounded by hepatic cysts. Surgery was performed and the pathological diagnosis was StageI gallbladder cancer.

Liver metastasis from rectal neuroendocrine neoplasm detected 15 years after primary resection.

BACKGROUND: Rectal neuroendocrine neoplasms can induce liver metastasis. However, few reports exist on the associated long-term recurrence rates. We report a case of liver metastasis identified 15 years after rectal neuroendocrine neoplasm resection. CASE PRESENTATION: A 50-year-old woman was on semi-annual follow-up after undergoing mastectomy for breast cancer (pT1N0M0) and low anterior resection for grade 1 rectal neuroendocrine neoplasm (pT1b, ly1, v1). Fifteen years postoperatively, a 7-mm hyperechoic mass was identified at liver segment 6. Magnetic resonance imaging revealed a slight growth of the mass. Positron emission tomography/computed tomography revealed radiotracer accumulation in the lesion. Laparoscopic hepatectomy was performed. The histopathological diagnosis was grade 2 neuroendocrine neoplasm. The pathological findings and clinical course indicated the tumor originated in the rectum. CONCLUSIONS: Our findings highlight the need to reassess the optimal postoperative follow-up period for patients with rectal neuroendocrine neoplasm.

Prognostic Advantages of Individual Additional Interventions After Lenvatinib Therapy in Patients with Advanced Hepatocellular Carcinoma.

BACKGROUND: Increasing number of patients with advanced hepatocellular carcinoma (HCC) has recently achieved salvage interventions after introduction of new biologic agents, while there are insufficient data to determine if such additional intervention(s) after treatment with newer biologic agents are truly advantageous for patients with advanced HCC. METHODS: The clinical records of 107 consecutive patients who underwent lenvatinib treatment for advanced HCC were extensively reviewed and the prognostic advantages of individual additional treatments after lenvatinib treatment were investigated through a regression analysis considering time-dependent covariates. RESULTS: Multivariate analysis revealed that R0 resection or curative-intent radiofrequency ablation (RFA) (hazard ratio [HR], 0.07; 95% CI, 0.01-0.32), transarterial chemoembolization or transarterial infusion therapy (HR, 0.39; 95% CI, 0.19-0.81), and subsequent line of systemic therapy (HR, 0.25; 95% CI, 0.10-0.63) were associated with improved disease-specific survival (DSS), while R2 resection or palliative-intent RFA showed no correlation with DSS. The best response during lenvatinib therapy, nutritional status, plasma des-gamma-carboxyprothrombin level, a baseline CT enhancement pattern, and BCLC stage were also selected as independent predictors for DSS. Among the various treatments performed after lenvatinib therapy, R0 resection also showed clear prognostic advantage in both progression-free survival (HR, 0.30; 95% CI, 0.16-0.58) and time-to-treatment failure (HR, 0.08; 95% CI, 0.02-0.39), suggesting that successful conversion to surgery may prolong survival outcomes through prolonged cancer-free interval in advanced HCC. CONCLUSIONS: Additional intervention(s)/treatment(s) after lenvatinib therapy for advanced HCC may have prognostic advantage in strictly selected populations. Successful conversion to curative resection may offer survival benefit with acceptable clinical outcomes.

Primary hepatic neuroendocrine neoplasm diagnosed by somatostatin receptor scintigraphy: A case report.

BACKGROUND: Primary hepatic neuroendocrine neoplasm (NEN) is a rare condition, and it is difficult to differentiate between primary and metastatic hepatic NENs. Herein, we report a case of primary hepatic NEN that initially mimicked a hemangioma but showed a gradual increase in size on long-term careful observation. CASE SUMMARY: A 47-year-old woman was incidentally diagnosed with a 12-mm liver mass, suspected to be a hemangioma. Since then, regular follow-up had been carried out. Ten years later, she was referred to our institute due to the tumor (located in segment 4) having increased to 20 mm. Several imaging studies depicted no apparent extrahepatic lesion. Positron emission tomography (PET)/computed tomography exhibited significant accumulation in the mass lesion, which made us consider the possibility of malignancy. Left hepatectomy was performed. The histopathological diagnosis was neuroendocrine tumor grade 2, with somatostatin receptor 2a/5 positivity. Postoperative somatostatin receptor scintigraphy (SRS) showed no other site, leading to the diagnosis of NEN of primary hepatic origin. The gradual growth of the hepatic NEN over 10 years suggested that it was likely to be a primary liver tumor. CONCLUSION: In this case, positivity on PET and postoperative SRS may have helped determine whether the tumor was primary or metastatic.

Pretreatment Positron Emission Tomography with 18F-Fluorodeoxyglucose May Be a Useful New Predictor of Early Progressive Disease following Atezolizumab plus Bevacizumab in Patients with Unresectable Hepatocellular Carcinoma.

BACKGROUND AND AIMS: The aim of this study was to identify the utility of 18F-fluorodeoxyglucose positron emission tomography/computed tomography (18F-FDG-PET/CT) as a predictor of early progressive disease (e-PD) in patients with hepatocellular carcinoma (HCC) treated with atezolizumab plus bevacizumab (Atezo/Bev). METHODS: Twenty consecutive patients with measurable intrahepatic target nodules who received Atezo/Bev treatment were reviewed. The oncological aggressiveness of tumors estimated by 18F-FDG-PET/CT was analyzed using the rate of e-PD within 12 weeks and early progression-free survival (e-PFS) and overall survival (OS). Multivariate analysis was used to identify potential confounders for PD during Atezo/Bev therapy. RESULTS: Using the Response Evaluation Criteria in Solid Tumors version 1.1, a tumor-to-normal liver ratio (TLR) ≥2, indicating higher oncological aggressiveness in HCCs, was associated with lower objective response rates compared with TLR values <2 (18% vs. 33%, respectively). Moreover, TLR values ≥2 were significantly associated with higher e-PD rates compared with TLR values <2 (64% vs. 11%, respectively) and worse e-PFS (p = 0.021). In multivariate analysis, TLR ≥2 showed marginal significance as a predictor of e-PD (p = 0.053), and utility as a predictor for worse e-PFS (hazard ratio, 7.153; 95% confidence interval, 1.258-40.689; p = 0.027). In contrast, no significant differences in OS with/without e-PD were observed during the treatment course. In this study, 8 patients experienced e-PD and almost 40% of patients experienced acceptable disease control following subsequent lenvatinib treatment. CONCLUSION: Pretreatment 18F-FDG-PET/CT may be a useful new predictor of e-PD and may enable early decision-making based on early treatment changes following Atezo/Bev treatment of HCC.

Indocyanine green fluorescence angiography-guided simultaneous laparoscopic distal gastrectomy and spleen-preserving distal pancreatectomy for conserving the gastrosplenic ligament: A case report.

INTRODUCTION AND IMPORTANCE: Indocyanine green (ICG) fluorescence angiography is being increasingly performed intraoperatively to detect restricted blood flow intraoperatively for the prevention of postoperative organ ischemia and anastomotic leakage. This is the first case report of simultaneous laparoscopic distal gastrectomy (LDG) and spleen-preserving distal pancreatectomy (LSPDP) involving ICG angiography use to avoid the remnant stomach ischemia. CASE PRESENTATION: A 55-year-old man was diagnosed with early cancer of the stomach body and intraductal papillary mucinous neoplasms of the pancreatic tail. We performed simultaneous LDG with D2 dissection and LSPDP to conserve the gastrosplenic ligament and preserve blood supply to the remnant stomach. Intraoperatively, blood flow to the remnant stomach was visualized using ICG fluorescence angiography, after which Roux-en-Y reconstruction was performed. There was no perioperative remnant stomach ischemia. CLINICAL DISCUSSION: Despite the preserved splenic artery and vein, complete splenic infarction occurs after LSPDP possibly due to thrombus formation during surgical procedures. In this patient, we conserved the gastrosplenic ligament for the short gastric artery, which supplied blood to the remnant stomach; however, remnant stomach ischemia may occur. Therefore, we performed ICG fluorescence angiography during this operation to ensure that sufficient blood supply to the remnant stomach was maintained. CONCLUSION: Our experience demonstrates that ICG angiography may be useful for the prevention of remnant stomach ischemia.

Leiomyosarcoma of the splenic vein with a history of bilateral retinoblastoma: A case report and review of the literature.

Diagnosing leiomyosarcomas of the splenic vein is challenging, and a treatment strategy has not yet been established for this condition. We herein report the case of a 45-year-old female patient with a history of retinoblastoma who underwent pancreatosplenectomy for a primary leiomyosarcoma originating from the splenic vein and transcatheter arterial chemoembolization for metastatic hepatic lesions observed 5 months postoperatively. An initial medical check-up using abdominal ultrasound revealed a 40-mm mass behind the pancreatic tail. Imaging tests revealed a well-circumscribed mass compressing the pancreas posteriorly, without invasion into the pancreatic duct. The splenic vein was torn, with the epiploic veins developed as collateral blood vessels, which was an atypical finding for carcinoma. The patient was followed up regularly. At 5 years after the first visit, an abdominal ultrasound showed that the mass had increased in size to 50 mm, and had developed into a tumor embolus within the splenic vein, causing an obstruction of the vessel. Pancreatosplenectomy was performed due to suspicion of malignancy. The final diagnosis was leiomyosarcoma arising from the splenic vein. The patient was discharged on postoperative day 15 and was followed up regularly thereafter. Imaging studies performed 5 months postoperatively revealed four hepatic lesions. The hepatic masses were histologically diagnosed as metastatic leiomyosarcomas, and transcatheter arterial chemoembolization was performed using epirubicin. Since then, regular follow-ups have been conducted without observed recurrence. Leiomyosarcoma of the splenic vein is exceedingly rare, and the number of reported cases is not sufficient to establish clinical guidelines. Therefore, it is crucial to collect more reports on the occurrence and treatment of this disease.