Long-term outcomes of robot-assisted versus minimally invasive esophagectomy in patients with thoracic esophageal cancer: a propensity score-matched study.

BACKGROUND: Recently, robot-assisted minimally invasive esophagectomy (RAMIE) has gained popularity worldwide. Some studies have compared the long-term results of RAMIE and minimally invasive esophagectomy (MIE). However, there are no reports on the long-term outcomes of RAMIE in Japan. This study compared the long-term outcomes of RAMIE and MIE. METHODS: This retrospective study included 86 patients with thoracic esophageal cancer who underwent RAMIE or MIE at our hospital from June 2010 to December 2016. Propensity score matching (PSM) was employed, incorporating co-variables such as confounders or risk factors derived from the literature and clinical practice. These variables included age, sex, body mass index, alcohol consumption, smoking history, American Society of Anesthesiologists stage, comorbidities, tumor location, histology, clinical TNM stage, and preoperative therapy. The primary endpoint was 5-year overall survival (OS), and the secondary endpoints were 5-year disease-free survival (DFS) and recurrence rates. RESULTS: Before PSM, the RAMIE group had a longer operation time (min) than the MIE group (P = 0.019). RAMIE also exhibited significantly lower blood loss volume (mL) (P < 0.001) and fewer three-field lymph node dissections (P = 0.028). Postoperative complications (Clavien-Dindo: CD ≥ 2) were significantly lower in the RAMIE group (P = 0.04), and postoperative hospital stay was significantly shorter than the MIE group (P < 0.001). After PSM, the RAMIE and MIE groups consisted of 26 patients each. Blood loss volume was significantly smaller (P = 0.012), postoperative complications (Clavien-Dindo ≥ 2) were significantly lower (P = 0.021), and postoperative hospital stay was significantly shorter (P < 0.001) in the RAMIE group than those in the MIE group. The median observation period was 63 months. The 5-year OS rates were 73.1% and 80.8% in the RAMIE and MIE groups, respectively (P = 0.360); the 5-year DFS rates were 76.9% and 76.9% in the RAMIE and MIE groups, respectively (P = 0.749). Six of 26 patients (23.1%) in each group experienced recurrence, with a median recurrence period of 41.5 months in the RAMIE group and 22.5 months in the MIE group. CONCLUSIONS: Compared with MIE, RAMIE led to no differences in long-term results, suggesting that RAMIE is a comparable technique.

[A Case of Early-Stage Cecal Cancer with Mesenteric Phlebosclerosis Requiring Laparoscopic Right Hemicolectomy of the Colon].

The patient was a 71-year-old woman diagnosed with mesenteric phlebosclerosis(MP)2 years earlier. CT performed to investigate her abdominal pain revealed an ascending colon obstruction. Colonoscopy(CS)revealed MP extending to the ascending colon hepatic flexure with stenosis and a cecal tumor(biopsy tub1). Although the cancerous lesion itself was potentially curable by endoscopic treatment, it was surgically resected because of the ascending colon stenosis caused by the MP that had also caused intestinal obstruction. Intraoperative findings revealed wall thickening and stiffening from the cecum to the ascending colon hepatic flexure. Postoperative pathological examination revealed cecal carcinoma pTis, N0, M0, pStage 0. The background mucosal tissue was consistent with MP, but no findings suggested a relationship between the MP and tumor. Although the relationship between MP and carcinogenesis is unknown, and no such relationship was identified in this case, we report this case because a further accumulation of cases of MP and carcinoma is necessary, considering the rarity of MP itself and the non-negligible number of cases with carcinoma.

[A Case of Rectal Cancer with Solitary Lymph Node Metastasis in the Stomach after Hepatectomy for Liver Metastasis].

A 44-year-old woman had undergone a laparoscopic low anterior resection and lymph node dissection for rectal cancer (pT4aN2aH0P0M0, pStage Ⅲc)in 20XX. Six months postoperatively, a CT scan revealed recurrent liver metastasis. She underwent surgery and adjuvant chemotherapy. Three years after the initial surgery, her liver metastasis recurred again, and the patient underwent another cycle of surgical treatment and adjuvant chemotherapy. Five years after the initial surgery, a lesion was found in a gastric lesser curvature lymph node. Gastric kyphosis lymph node dissection was performed under the suspicion of a solitary lymph node metastasis. The resected lymph node was diagnosed as a medium-differentiated adenocarcinoma, with findings consistent with a lymph node metastasis from the initial rectal cancer. Postoperative adjuvant chemotherapy was administered. No recurrence was noted 6 years and 6 months after the initial surgery. Rectal cancer rarely metastasizes to the gastric lymph nodes in a solitary fashion. We describe a case of a solitary gastric regional lymph node metastasis observed after the resolution of previous liver metastases.

[Preoperative Prognostic Factors in CRS plus HIPEC for Patients with Peritoneal Dissemination of Colorectal Cancer].

Peritoneal dissemination of colorectal cancer has the poorest prognosis among metastatic sites, with an average overall survival of less than 6 months. Various treatment methods have been reported for these patients, and recently there have been several reports showing the usefulness of cytoreductive surgery(CRS)combined with hyperthermic intraperitoneal chemotherapy (HIPEC). However, the studies on this treatment are limited. In this study, we retrospectively reviewed cases of CRS plus HIPEC. Twenty-one patients who underwent CRS plus HIPEC at Tokyo Medical University Hospital and Toda Central General Hospital between August 2014 and December 2017 were included in this study. The long-term and short-term survival groups were analyzed separately, and predictors of preoperative treatment efficacy were examined. The surgical approach was open in 16 cases and laparoscopic in 5 cases. Complete resection was achieved in 10 of these patients. Postoperative complications occurred in 6 patients. There were no deaths within 90 days of surgery. The median overall survival was 17.0 months, and the 1-year survival rate was 65%. Median progression-free survival was 11.0 months. In a multivariate analysis predicting long-term versus short-term survival groups, sex, primary tumor location, and P factor were independent predictors of treatment response. CRS plus HIPEC therapy is considered an effective treatment option. The predictors of preoperative treatment response include sex, primary tumor location, and P factor.

Salivary metabolomics with machine learning for colorectal cancer detection.

As the worldwide prevalence of colorectal cancer (CRC) increases, it is vital to reduce its morbidity and mortality through early detection. Saliva-based tests are an ideal noninvasive tool for CRC detection. Here, we explored and validated salivary biomarkers to distinguish patients with CRC from those with adenoma (AD) and healthy controls (HC). Saliva samples were collected from patients with CRC, AD, and HC. Untargeted salivary hydrophilic metabolite profiling was conducted using capillary electrophoresis-mass spectrometry and liquid chromatography-mass spectrometry. An alternative decision tree (ADTree)-based machine learning (ML) method was used to assess the discrimination abilities of the quantified metabolites. A total of 2602 unstimulated saliva samples were collected from subjects with CRC (n = 235), AD (n = 50), and HC (n = 2317). Data were randomly divided into training (n = 1301) and validation datasets (n = 1301). The clustering analysis showed a clear consistency of aberrant metabolites between the two groups. The ADTree model was optimized through cross-validation (CV) using the training dataset, and the developed model was validated using the validation dataset. The model discriminating CRC + AD from HC showed area under the receiver-operating characteristic curves (AUC) of 0.860 (95% confidence interval [CI]: 0.828-0.891) for CV and 0.870 (95% CI: 0.837-0.903) for the validation dataset. The other model discriminating CRC from AD + HC showed an AUC of 0.879 (95% CI: 0.851-0.907) and 0.870 (95% CI: 0.838-0.902), respectively. Salivary metabolomics combined with ML demonstrated high accuracy and versatility in detecting CRC.

Postoperative complications, bowel function, and prognosis in restorative proctocolectomy for ulcerative colitis-a single-center observational study of 320 patients.

PURPOSE: To determine the selection criteria, postoperative complications, bowel function, and prognosis of stapled ileal pouch-anal anastomosis (IPAA) and hand-sewn IPAA for ulcerative colitis (UC). METHODS: We defined our surgical indications and strategy, and compared the postoperative complications, bowel function, and prognoses between patients who underwent stapled and hand-sewn IPAA for UC at the Yokohama City University Medical Center between 2004 and 2017. RESULTS: Among 320 patients enrolled, 298 patients underwent stapled IPAA while 22 underwent hand-sewn IPAA. There was no significant difference in the postoperative complications between the two groups. Regarding postoperative bowel function, stapled IPAA caused significantly less soiling (stapled vs hand-sewn: 9.1% vs 41.0%, odds ratio (OR) = 0.14, p < 0.0002), spotting (stapled vs hand-sewn: 23.2% vs 63.6%, OR = 0.17, p < 0.0001), and difficulty in distinguishing feces from flatus (stapled vs hand-sewn: 39.9% vs 63.6%, OR = 0.36, p < 0.026). No postoperative neoplasia was observed at the final follow-up in all patients. CONCLUSION: In this study, there was no clear difference in the postoperative complications between stapled and hand-sewn IPAA, but stapled IPAA resulted in better postoperative bowel function. Postoperative oncogenesis from the residual mucosa is rare. However, future cancer risk remains; thus, careful follow-up is required.

A new technique for robotic lateral pelvic lymph node dissection for advanced low rectal cancer with emphasis on en bloc resection and inferior vesical vessel preservation.

BACKGROUND: Lateral pelvic lymph node (LPLN) dissection is becoming increasingly important in the treatment of advanced low rectal cancer patients. However, the surgery has several disadvantages, including its technical complexity and high risk of urinary dysfunction. Herein, we report a new technique for robotic lateral pelvic lymph node dissection for advanced low rectal cancer with emphasis on en bloc resection and inferior vesical vessel preservation. METHODS: Robotic LPLN dissection was performed in 12 consecutive patients between April 2020 and December 2021. Six surgical ports were placed in the abdomen under general anesthesia. Fascia-oriented LPLN dissection of the internal iliac region and obturator region was performed using the ureterohypogastric nerve fascia, vesicohypogastric fascia, and internal obturator muscles as anatomical landmarks. Lymph nodes were resected en bloc via the caudal side of the inferior vesical vessels. The inferior vesical vessels were spared to prevent urinary dysfunction. RESULTS: The median patient age was 62 years (range, 43-82 years), and eight patients were male. The median operative time was 498 min (range, 424-661 min), the median bleeding volume was 56 ml (range, 13-467 ml), and the median number of harvested LPLN was 16 (range, 1-70). The conversion rate to open surgery was 0%. Clavien-Dindo Grade ≥ II urinary dysfunction rated was not observed. CONCLUSION: A new technique for robotic LPLN dissection for advanced low rectal cancer with emphasis on en bloc resection and inferior vesical vessel preservation can be safely performed, making it a promising surgical procedure.

Laparoscopic middle colic artery-preserved right hemicolectomy with true D3 lymph node dissection for right-sided colon cancer: modified complete mesocolic excision.

BACKGROUND: Complete mesocolic excision (CME) has been demonstrated to be a useful surgical procedure for advanced colon cancer. We previously reported on laparoscopic (Lap) CME with true central vascular ligation (CVL) for advanced right-sided colon cancer. Lap CME with true CVL is highly plausible from the perspective of surgical oncology. However, true CVL of the middle colic artery (MCA) may require extensive resection of the transverse colon. The Japanese Classification of Colorectal Cancer defines D3 as main lymph node dissection around the superior mesenteric artery (SMA), and true CVL is not listed as a required condition. Our institution has been performing a Lap procedure (Lap D3/modified CME) that consists of the dissection of main lymph nodes around the root of the MCA (#223LNs) while preserving the left branch of the MCA. Two videos of a Lap D3/modified CME are presented, and the short-term outcome is reported. METHODS: Lap D3/modified CME was defined as Lap ligation surgery at the root of the right branch of the MCA that preserves the MCA with #223LNs on the resection side. The present study retrospectively examined 11 cases of Lap D3/modified CME performed at the Tokyo Medical University Hospital between 2015 and 2020. When the SMA is difficult to visualize in Type V/A cases, the SMV is pulled using some silicone string, and the surrounding lymph nodes are dissected while visualizing the SMA. RESULTS: The median operating time was 289 min, and the median blood loss was 57 ml. The median total number of dissected lymph nodes was 38, and the median number of dissected #223LNs was three. No metastasis was found in the dissected #223LNs. CONCLUSION: Although this surgery can be performed safely, we believe that this surgery needs to be performed for suitable cases by a highly experienced and skilled surgical team.

[A Case of Gastrointestinal Stromal Tumor(GIST)of the Sigmoid Colon with Early Colon Cancer].

A 67-year-old male patient was referred to our department for fecal occult blood in March 2019. In April, lower intestinal endoscopic examination revealed a 25-mm pedunculated polyp in the sigmoid colon. Endoscopic mucosal resection was then performed. The pathological diagnosis was tub1-tub2 with an invasion depth of pT1b 3,000 µm, and ly0 and v1 vascular invasion. The tumor marker levels were normal, with CEA of 1.1 ng/mL and CA19-9 of 13.9 U/mL. An additional laparoscopic low anterior resection and D2 dissection were performed in June. After the endoscopic mucosal resection, pathologic examination revealed densely hyperplastic spindle cells arranged in bundles at the proper muscular layer of the scar site. There was no lymph node metastasis. On immunostaining, the lesion tested positive for c-kit, CD34, and DOG1, but negative for desmin, SMA, and S-100, with a MIB-1 index of 2%. The patient was diagnosed with very low risk gastrointestinal stromal tumor(GIST). We encountered a rare case of early sigmoid colon cancer, complicated by sigmoid colon GIST.

Neutrophil-to-lymphocyte ratio is a prognostic factor for colon cancer: a propensity score analysis.

BACKGROUND: A large number of patients suffer recurrence after curative resection, and mortality from colon cancer remains high. The role of systemic inflammatory response, as reflected by neutrophil-to-lymphocyte ratio (NLR), in cancer recurrence and death has been increasingly recognized. This study aimed to analyze long-term oncologic outcomes of Stage II-III colon cancer to examine the prognostic value of NLR using a propensity score analysis. METHODS: A total of 375 patients with colon cancer underwent radical surgery between 2000 and 2014 at Tokyo Medical University Hospital. Long-term oncologic outcomes of these patients were evaluated according to NLR values. A cut-off NLR of 3.0 was used based on receiver operating characteristic curve analysis. Primary outcomes were overall survival (OS) and relapse-free survival (RFS). An analysis of outcomes according to tumor sidedness was also performed. RESULTS: Patients with lower NLR values ("lower NLR group") were more likely to have lymph node metastasis compared to those with higher NLR values ("higher NLR group") before case matching. After case matching, clinical outcomes were similar between the two groups. There were no significant differences in 5-year OS and 5-year RFS rates between the two groups before case matching based on propensity scores. After case matching, 5-year OS rates were 94.5% in the lower NLR group (n = 135) and 87.0% in the higher NLR group (n = 135), showing a significant difference (p = 0.042). Five-year RFS rates were 87.8% in the lower NLR group and 77.9% in the higher NLR group, also showing a significant difference (p = 0.032). Among patients with left-sided colon cancer in the matched cohort, 5-year OS and 5-year RFS rates were 95.2 and 87.3% in the lower NLR group (n = 88), respectively, and 86.4 and 79.2% in the higher NLR group (n = 71), respectively, showing significant differences (p = 0.014 and p = 0.047, respectively). CONCLUSIONS: The NLR is an important prognostic factor for advanced colon cancer, especially for left-sided colon cancer.

Laparoscopic complete mesocolic excision with true central vascular ligation for right-sided colon cancer.

BACKGROUND: Complete mesocolic excision (CME) is known to be effective for colon cancer. However, in right-sided colon cancer, central vascular ligation (CVL) is not easy to perform. In particular, in patients in whom the superior mesenteric vein (SMV) runs on the ventral side of the superior mesenteric artery (SMA) (Type V/A), laparoscopic ligation of the artery at its root is extremely difficult compared with this procedure in patients in whom the SMA runs on the ventral side of the SMV (Type A/V). METHODS: We started performing laparoscopic CME with true CVL for right-sided colon cancer using the SMA as a landmark in 2015, and by 2019, we had completed it for 60 patients. To start, the mesocolon is opened well to the caudal side of the ileocolic vessels. The mesentery is then fully detached from the retroperitoneal tissue, after which the ileocolic vessels are ligated at their roots. D3 lymph node dissection of the lymph nodes around the SMA and SMV on the resection side is also performed using the SMA as a landmark, and depending on the location of the tumor, the roots of the right and middle colic vessels are ligated and divided. This study was conducted with the approval of the Tokyo Medical University Ethics Committee. All patients provided informed consent. RESULTS: The tumor was located in the cecum in 21 cases, the ascending colon in 33, and the transverse colon in 6. The mean operating time was 229 min and the mean volume of hemorrhage was 67 ml. There was one Clavien-Dindo Grade 3 or worse postoperative complication (ileus). There were no surgery-related or in-hospital deaths. CONCLUSION: This procedure can be performed comparatively safely. However, since it requires some skill, we consider that it should only be performed in suitable cases by teams with sufficient experience.

The glomuvenous malformation protein Glomulin binds Rbx1 and regulates cullin RING ligase-mediated turnover of Fbw7.

Fbw7, a substrate receptor for Cul1-RING-ligase (CRL1), facilitates the ubiquitination and degradation of several proteins, including Cyclin E and c-Myc. In spite of much effort, the mechanisms underlying Fbw7 regulation are mostly unknown. Here, we show that Glomulin (Glmn), a protein found mutated in the vascular disorder glomuvenous malformation (GVM), binds directly to the RING domain of Rbx1 and inhibits its E3 ubiquitin ligase activity. Loss of Glmn in a variety of cells, tissues, and GVM lesions results in decreased levels of Fbw7 and increased levels of Cyclin E and c-Myc. The increased turnover of Fbw7 is dependent on CRL and proteasome activity, indicating that Glmn modulates the E3 activity of CRL1(Fbw7). These data reveal an unexpected functional connection between Glmn and Rbx1 and demonstrate that defective regulation of Fbw7 levels contributes to GVM.

[Esophagogastric Junctional Adenocarcinoma Responding Completely to Chemotherapy in an Elderly Patient with Long-Term Survival and No Recurrences-A Case Report].

An 85-year-old man was diagnosed with esophagogastric junctional adenocarcinoma, E=G, Type 2, por, 6 cm in size, cT4aN1M0, cStage ⅢA. He had a history of atherosclerosis obliterans and thoracoabdominal aortic aneurysm. Considering the comorbidities and life expectancy, we decided to perform chemotherapy without tumor resection. Although the renal function was poor, we chose SP therapy(S-1 80mg/kg/day for 14 days, followed by 7-day rest, CDDP 30mg/kg/day on day 1)because the current status of the patient was satisfactory. The primary tumor remarkably shrank after 2 courses of SP therapy and completely disappeared after 5 courses of SP therapy. There were no adverse events during the entire course of treatment. We detected clinical CR and provided the S-1 monotherapy for another 2 years. The patient has survived with no recurrences for 7 years since the initial chemotherapy. Although intensive chemotherapy regimens are avoided in elderly patients, the patient, in this case, showed a favorable prognosis from powerful chemotherapy.

[Two Cases of Neuroendocrine Carcinoma of Colon and Rectum].

We report 2 cases of neuroendocrine carcinoma(NEC)of colon and rectum with distant metastasis. The treatment of NEC with distant metastasis is based on the treatment of small cell lung cancer, but that is controversial because NEC is relatively rare. Case 1: A 75-year-old man who was admitted for anal pain. Physical examination showed the anal tumor and swelling inguinal lymph nodes. CT showed rectum tumor and multiple lymph node metastases to the pelvis and inguinal region. Colonoscopy showed a Type 3 tumor in the rectum. He was diagnosed with NEC based on biopsy and immunostaining. Colostomy was performed for pain relief and etoposide/cisplatin(EP)therapy was introduced. After 6 courses of the chemotherapy, CT showed progression of the tumor, then we made the shift to palliative treatment. Case 2: A 69-year-old man who was admitted for abdominal pain and back pain. CT showed transverse colon tumor with multiple metastases to the liver, lung, and lymph nodes. Colonoscopy showed a circumferential tumor in the transverse colon. He was diagnosed with NEC based on biopsy and immunostaining. He refused chemotherapy and died 2 months later.

[A Case of BRAF-Mutated Obstructive Colon Cancer with Liver Metastases Treated with Multidisciplinary Therapy].

A 39-year-old woman visited our hospital with complaints of nausea, vomiting, and lower abdominal pain for 2 weeks. Abdominal CT revealed thickening of the transverse colonic wall, dilated bowel, and a metastatic ischemic tumor in the liver (S7). We diagnosed her with obstructive colon cancer, clinical Stage Ⅳa(T, type 2, cT3, N0, M1a[liver]). At first, we placed a self-expanding metallic stent(SEMS)to decompress bowel obstructions. We planned a surgical resection of the primary tumor followed by partial resection of the liver. We performed a laparoscopic right hemicolectomy(D3)24 days after the stenting. Pathologically, we diagnosed her with BRAF-mutated colon cancer, pStage Ⅳa(pT4a, N1b[2/43], M1a[liver]). On completion of 4 courses of mFOLFOXIRI and bevacizumab, we confirmed a reduction of the S7 tumor but found a new tumor in S6. Since the tumors were potentially resectable, we performed partial liver resection(S6, S7)1 month later. A month following the hepatectomy, CT revealed a new tumor in S4. The patient has been receiving general chemotherapy (CapeOX and bevacizumab)without disease progression for 6 months. We experienced a challenging case of BRAF- mutated obstructive colon cancer with liver metastases.

[A Case of Intussusception Caused by Ascending Colon Cancer in an Elderly Woman].

In September 2015, a 90-year-old woman presented with abdominal pain and emesis as the chief complaints. Except for WBC counts of 10,420/mL, CRP levels of 5.69mg/dL, and ALP levels of 359 IU/L, no other abnormal values were noted, and CEA and CA19-9 tumor marker levels were normal at 3.9 ng/mL and 5.7 U/mL, respectively. Abdominal CT showed intussusception of the right colon and a solid tumor at the presenting portion. Surgery for suspected intussusception caused by colon cancer was performed. Surgical findings revealed a protruding lesion at the ascending colon that extended to the transverse colon, and the intussusception was intrusive up to the ascending colon at the end of the intestinal ileum. Thus, resection of the right half colon and dissection of lymph nodes were performed. Resected specimens revealed a type 1 tumor measuring 65×50×30mm in diameter at the ascending colon. Histopathologic findings revealed tub1>tub2, SS, ly0, v0, PM0, DM0, N0 (0/27)Stage Ⅱa tumor. The postoperative course was favorable, and the patient was discharged on postoperative day 12. We report about a rare case of intussusception caused by ascending colon cancer.

[Examination of Treatment Results and Risk Factors for Recurrence of Advanced Lower Rectal Cancer].

BACKGROUND: The standard treatment in Japan for advanced lower rectal cancer is total mesorectal excision(TME)plus lateral lymph node dissection(LLND). However, the standard treatment in Western countries is preoperative treatment plus TME. There have been some discussions on preoperative chemotherapy and chemoradiation therapy. This study was aimed at identifying the prognostic factors of recurrence after curative surgery for advanced lower rectal cancer. METHODS: A total of 54 patients with advanced lower rectal cancer who had undergone curative operation at our department from 2010 to 2015 were retrospectively analyzed, excluding patients with both LLND and preoperative therapy. The primary endpoint of this study was the 5-year recurrence-free survival(5RFS). RESULTS: The overall 5RFS was 57.6%. The univariate analysis demonstrated that lymph node metastasis(p=0.038)and radial margin(RM, p=0.015)were significant risk factors, with a 5RFS of 39.7% and 0%, respectively. The multivariate analysis revealed that only RM significantly affected 5RFS(p= 0.009). CONCLUSION: Our results suggest that securing an adequate circumferential resection margin together with proper surgical technique and preoperative therapy are important for decreasing postoperative recurrence rates of advanced lower rectal cancer.

[A Case of Long-Term Survival of a Postoperative Recurrence of Duodenal Papilla Adenosquamous Carcinoma Associated with the Annular Pancreas].

A woman in her mid-50's presented to our hospital with jaundice, fatigue, and fever. Jaundice, elevated tumor markers, and lower bile duct stricture suggested malignancy, for which subtotal stomach-preserving pancreaticoduodenectomy was performed. The patient also had annular pancreas as the second part of the duodenum was surrounded by pancreatic parenchyma. The histopathological diagnosis was adenosquamous carcinoma of the duodenal papilla associated with annular pancreas. Adjuvant chemotherapy with TS-1 was administered for 1 year. Although para-aortic lymph node metastasis was detected radiographically 3 years 9 months after surgery, the recurrence remains under control and she is alive at 5 years 9 months after surgery due to multidisciplinary therapy.

[A Successful Case of Multimodal Therapy for Multiple Hypervascular Tumor of Unknown Primary Origin in the Liver].

We experienced a successful case in which the patient was treated with a combination of operation and transcatheter arterial chemoembolization for a hypervascular tumor of unknown primary origin in the liver; we report this case with a literature review. A 76-year-old man noticed an upper abdominal tumor and he visited our department for detailed examination. Enhanced CT scan showed multiple hypervascular tumors scattered across both lobes of the liver, and the pattern of contrast effect implied that the tumors were primary neuroendocrine tumors or endocrine metastases. Gastroscopy and colonoscopy showed no tumor in the intestine. TACE was performed mainly for the tumors in the right lobe. One month later, we performed left lateral segmentectomy and partial hepatectomy for segment 6. Histopathological findings showed that the tumors in the left lateral segment had neuroendocrine properties, and the tumor in segment 6 was necrosed. One year has passed since the surgery without recurrence of neuroendocrine tumors in the liver or other organs.

[A Case of Advanced Gastric Cancer with Right Gastroepiploic Vein Tumor Thrombus Treated by Preoperative S-1 plus CDDP That Resulted in Pathological Complete Response].

We report a case of advanced gastric cancer with right gastroepiploic vein tumor thrombus treated using preoperative S-1 plus cisplatin(CDDP)in which pathological complete response was achieved. A 78-year-old man was diagnosed with type 2 gastric cancer located at the greater curvature of the antrum, accompanied by right gastroepiploic vein tumor thrombus. Four courses of S-1 plus CDDP were administered as neoadjuvant chemotherapy. After 2 courses, computed tomography(CT) revealed the disappearance of the tumor in the right gastroepiploic vein thrombus. Distal gastrectomy with D2 lymphadenec- tomy was performed, and the diagnosis was pathological complete response(CR). Eight courses of S-1(100mg/day on days 1-28, followed by 2 weeks of rest)were administered as adjuvant chemotherapy. During the 1-year postoperative follow up, the patient showed no recurrence. An S-1 plus CDDP regimen can be a useful preoperative chemotherapy option for advanced gastric cancer with tumor vein thrombus.