Utility of Assessing Early Tumor Shrinkage as an Efficacy Predictor in Patients with Non-Surgically Indicated or Recurrent Esophageal Cancer Treated with Nivolumab plus Ipilimumab.

INTRODUCTION: Nivolumab plus ipilimumab combination therapy has been administered as a first-line treatment in Japan since 2022 for patients with unresectable progressive or recurrent esophageal cancer. The efficacy and safety of this immune checkpoint inhibitor (ICI) doublet therapy are now being evaluated, and it is necessary to identify populations that benefit from this treatment at an early phase after initiation. For patients not showing early benefit, changing as soon as possible to other therapeutic strategies could improve their survival outcomes. Therefore, we attempted to identify decision-making factors such as early tumor shrinkage (ETS) based on treatment experience with ICI doublet therapy. METHODS: The study included 19 patients who received nivolumab plus ipilimumab for non-surgically indicated or recurrent esophageal cancer between July 2022 and November 2023. Tumors were assessed approximately every 2 months after treatment initiation. The effects of ETS, depth of response (DpR), and clinicopathologic features, including immune-related adverse events (irAEs), on progression-free and overall survival were evaluated using Kaplan-Meier plots and Cox proportional hazard models. RESULTS: The mean duration of ICI doublet administration was 5.89 months (range, 1-16 months). At first evaluation, patients who exhibited no tumor progression >20% indicated possible response to ICI doublet therapy, and patients whose tumors shrank even minimally exhibited favorable progression-free survival. Higher DpR at any cut-off line exhibited better progression-free survival than those with lower DpR. Fifteen patients experienced irAEs, with 13 of these patients experiencing irAEs within 3 months of treatment initiation. irAEs were associated with the efficacy of ICI doublet therapy, but efficacy could not be predicted based on early irAE experience. CONCLUSION: ETS-high, DpR-high, and irAEs might be associated with favorable responses to nivolumab plus ipilimumab. As a predictor of efficacy at an early phase, ETS >0% could be a deciding factor for continuing ICI doublet therapy.

Robot-assisted minimally invasive esophagectomy for esophageal cancer in the left lateral decubitus position.

BACKGROUND: The use of robot-assisted minimally invasive esophagectomy (RAMIE) in the prone position for esophageal cancer has been currently increasing worldwide. In future, as surgical-assisted robots become more widespread, it is estimated that only two methods of transthoracic approach will remain: RAMIE and open thoracotomy for thoracic esophageal cancer. RAMIE in the left lateral decubitus position (RAMIE-LLDP) has the same field of view as open thoracotomy, is safe in emergency situations, and provides education on open thoracotomy. METHODS: Between September 2020 and April 2024, RAMIE-LLDP was performed in 64 consecutive patients with esophageal cancer. RAMIE-LLDP was performed with the operating table rotated and tilted 45° to the ventral side under artificial pneumothorax. The hand-control setting of the surgical-assist robot system was reversed left to right when the Patient Cart was rolled from the same direction as the RAMIE in the prone position. RESULTS: The mean total surgery and console times during the thoracic procedure were 254-min overall and 225 min in the last 24 cases and 195-min overall and 178- min in the last 24 cases, respectively. The mean amount of blood loss was 203.4 g overall and 28.3 g in the last 24 cases. Postoperative recurrent laryngeal nerve palsy with Clavien-Dindo classification (CD) was ≥ 2 in six patients (9.4%). Postoperative pneumonia with CD ≥ 2 was observed in 11 patients (17.2%). Conversion to open thoracotomy was observed in three patients (4.7%). In all three patients, an immediate conversion to thoracotomy without patients' position change was actually possible and no serious complications were noted. No mortality occurred within 30 days postoperatively. CONCLUSION: RAMIE-LLDP which facilitates emergency thoracotomy has perioperative results comparable to those of conventional thoracoscopic esophagectomy and is educational for open surgery. RAMIE-LLDP is the safest and most optimal surgery for esophageal cancer.

Optimal extent of lymph node dissection for high-risk gastric cancer stratified by a national clinical database risk calculator.

BACKGROUND: For patients with gastric cancer, a well-balanced treatment that considers both oncological aspects and surgical risk is demanded. This study aimed to explore the optimal extent of lymph node dissection (LND) for patients with gastric cancer according to surgical risk, stratified by the risk calculator system produced by the Japan National Clinical Database (NCD). PATIENTS AND METHODS: We retrospectively evaluated 187 patients who underwent radical gastrectomy for gastric cancer. Using the median predicted anastomotic leak rate obtained by the NCD risk calculator as the cutoff value, we classified 97 and 90 patients as having high and low risks, respectively. RESULTS: In low-risk patients, although limited LND reduced the postoperative intraabdominal infectious complications (IAIC), multivariate analysis revealed standard LND as an independent prognostic factor that improved Relapse-free survival (RFS). In high-risk patients, the rates of postoperative IAIC and RFS were similar between standard and limited LND. Pancreatic fistula was not observed in the limited dissection group. CONCLUSION: Limited LND might be the optimal treatment strategy for patients with gastric cancer with high surgical risk.

Effects of an artificial pancreas on postoperative inflammation in patients with esophageal cancer.

PURPOSES: Subtotal esophagectomy for esophageal cancer (EC) is associated with high morbidity rates. Tight glycemic control using an artificial pancreas (AP) is one of the promising strategies to reduce postoperative inflammation and morbidities. However, the effects of tight glycemic control using AP in patients with EC are yet to be fully elucidated. METHOD: This study reviewed 96 patients with EC who underwent subtotal esophagectomy. The postoperative inflammation parameters and morbidity rates were compared between patients who used the AP (n = 27) or not (control group, n = 69). AP is a closed-loop system that comprises a continuous glucose monitor and an insulin pump. RESULTS: The numbers of white blood cells (WBC) and Neutrophils (Neut) were noted to be lower in the AP group than in the control group, but with no significant difference. The ratio in which the number of WBC, Neut, and CRP on each postoperative day (POD) was divided by those tested preoperatively was used to standardize the results. The ratio of WBC and Neut on 1POD was significantly lower in the AP group than in the control group. The rate of surgical site infection was lower in the AP group than in the control group. CONCLUSION: AP significantly decreased WBC and Neut on 1POD; this suggests the beneficial effects of AP in alleviating postoperative inflammation.

Prognostic significance of the Naples prognostic score in colorectal cancer patients undergoing curative resection: a propensity score matching analysis.

BACKGROUND: Systemic inflammation is recognized as a hallmark of cancer that contributes to tumor development and progression in various malignancies. The Naples prognostic score (NPS) was established as a prognostic indicator for colorectal cancer (CRC). This study aims to examine the predictive value of the NPS for survival in CRC patients undergoing curative resection by a propensity score matching (PSM) analysis. METHODS: A total of 533 CRC patients were enrolled in this study. Overall survival (OS) and disease-free survival (DFS) were compared between high-NPS and low-NPS groups. A time-dependent receiver operator characteristic (ROC) curve analysis was conducted to calculate the area under curve (AUC) of the NPS for OS. A multivariable Cox-proportional hazards regression analysis and PSM analysis were used to identify independent prognostic factors for OS and DFS. We compared the predictive value of the NPS to that of the neutrophil-to-lymphocyte ratio (NLR), lymphocyte-to-monocyte ratio (LMR), platelet-to-lymphocyte ratio (PLR), Onodera prognostic nutritional index (PNI), and controlling nutritional status score (CONUT) for OS. RESULTS: High-NPS was significantly associated with worse OS and DFS. After PSM, 123 patients were included in each group. A multivariate analysis revealed that Age ≥ 68, ASA-PS ≥ 3, high NPS and undifferentiated tumor type were independently associated with OS, while high NPS, advanced T and N stage were independently associated with DFS after PSM. The NPS had the greatest AUC for OS in comparison to the NLR, LMR, PNI and CONUT. CONCLUSIONS: We successfully validated the prognostic utility of the NPS for CRC patients after curative resection.

Predictive value of the Naples prognostic score on postoperative outcomes in patients with rectal cancer.

PURPOSE: The Naples prognostic score (NPS) is a prognostic index based on the nutritional and inflammatory status. However, its utility in predicting postoperative complications (POCs) has not been examined in rectal cancer (RC). We evaluated the predictive value of the preoperative NPS for POCs in RC. METHODS: We retrospectively analyzed 235 patients who underwent surgery for RC. The NPS was calculated based on serum albumin, serum total cholesterol, the neutrophil-to-lymphocyte ratio (NLR) and the lymphocyte-to-monocyte ratio (LMR). Severe POCs were defined as Clavien-Dindo classification grade ≥ III. The optimal cut-off value of the NPS was determined by a receiver operator characteristic (ROC) curve analysis. The NPS, NLR, LMR, platelet-to-lymphocyte ratio (PLR), C-reactive protein (CRP)-to-albumin ratio (CAR), Glasgow prognostic score (GPS), Onodera prognostic nutritional index (PNI) and controlling nutritional status score (CONUT) were investigated as inflammation-based and/or nutritional markers. Predictors of severe POCs were analyzed by logistic regression modeling. RESULTS: Severe POCs were observed in 64 patients (27.2%). Male sex, operation time (> 257 min), blood loss (≥ 30 mL), albumin (< 4.0 g/dL), CRP (≥ 1.0 mg/dL), total cholesterol (≤ 180 mg/dL), NPS (≥ 2), LMR (≥ 3.48), PLR (≥ 103.6), CAR (> 0.025), GPS (≥ 1), PNI (< 48.1) and CONUT (≥ 2) were significantly associated with severe POCs. The multivariate analysis revealed that male sex, operation time (> 257 min), and a high NPS (≥ 2) were independent predictors of severe POCs. The ROC curve analysis revealed that the NPS had the greatest predictive value among the inflammation-based and/or nutritional markers. CONCLUSION: The NPS is a valuable predictor of severe POCs in RC.

Impact of a circular powered stapler on preventing anastomotic leakage in patients with left-sided colorectal cancer: a retrospective study.

BACKGROUND: The powered circular stapler, which was developed with the aim of providing reliable and reproducible anastomosis, provides complete anastomosis, resulting in a reduced risk of anastomotic leakage. The aim of this study was to compare the incidence of anastomotic leakage between a conventional manual circular stapler (MCS) and the ECHELON CIRCULAR™ Powered Stapler (ECPS) in patients with left-sided colorectal cancer who underwent anastomosis with the double stapling technique. METHODS: A total of 187 patients with left-sided colorectal cancer who underwent anastomosis with the double stapling technique with a conventional MCS or the ECPS during surgery at Osaka City University Hospital between January 2016 and July 2022 were enrolled in this study. RESULTS: The incidence of anastomotic leakage in the ECPS group was significantly lower than that in the MCS group (4.4% versus 14.3%, p = 0.048). Furthermore, even after propensity score matching, an association was found between the use of the ECPS and a reduced incidence of anastomotic leakage. CONCLUSION: The ECPS has the potential to help reduce the rate of anastomotic leakage in left-sided colorectal surgery.

Efficacy of the polyglycolic acid sheet for preventing anastomotic leakage in double-stapling technique anastomosis for left-sided colon or rectal cancer surgery: a propensity score-matched study.

BACKGROUND: To prevent anastomotic leakage in patients with left-sided colorectal cancer who underwent double-stapling technique (DST) anastomosis, we investigated a new method: DST anastomosis with a polyglycolic acid (PGA) sheet. This procedure has been shown to have the potential to decrease the rate of anastomotic leakage. However, due to the small number of cases enrolled in our previous study, it was not possible to compare the outcomes of the new and conventional procedures. The aim of this study was to evaluate the effect of the PGA sheet on preventing anastomotic leakage in patients with left-sided colorectal cancer who underwent DST anastomosis by retrospectively comparing the anastomotic leakage rate between the PGA sheet and conventional groups. METHODS: A total of 356 patients with left-sided colorectal cancer who underwent DST anastomosis during surgery at Osaka City University Hospital between January 2016 and April 2022 were enrolled in this study. Propensity score matching was performed to reduce the confounding effects secondary to imbalances in the use of PGA sheets. RESULTS: The PGA sheet was used in 43 cases (PGA sheet group) and it was not used in 313 cases (conventional group). After propensity score matching, the incidence of anastomotic leakage in the PGA sheet group was significantly lower than that in the conventional group. CONCLUSION: DST anastomosis with PGA sheet, which is easy to perform, contributes to the reduction of anastomotic leakage rate by increasing the strength of the anastomotic site.

[The Role of Cancer-Associated Fibroblasts in Modulating Tumor Immunity in Colorectal Cancer].

Cancer-associated fibroblasts(CAFs)remodel the extracellular matrix(ECM)and shape the tumor microenvironment (TME), resulting in immune escape and the promotion of tumor metastasis. Using an orthotopic tumor model of colorectal cancers(CRCs)in mice, we demonstrated that the single-cell RNA sequencing of orthotopic rectal tumors identified a subpopulation of CAFs that modulate the immune response. In this review, we report that understanding the role of CAFs in the TME concerning tumor immunity may lead to future avenues for CAF-targeted therapy.

[A Case of Robot-Assisted Abdominoperineal Resection Alongside En Bloc Prostatectomy and Vesico-Urethral Anastomosis for Local Recurrence].

A 66-year-old man presenting with cStage Ⅲc rectal cancer underwent laparoscopic low anterior resection(D3 lymph node dissection and R0 resection)following neoadjuvant chemoradiotherapy(capecitabine, 45 Gy/25 Fr)and received adjuvant chemotherapy(CAPOX). A year after surgery, abdominal contrast-enhanced computed tomography revealed recurrence near the rectal anastomosis with prostate invasion. The patient underwent robot-assisted abdominoperineal resection alongside en bloc prostatectomy and vesico-urethral anastomosis after 12 courses of neoadjuvant chemotherapy(FOLFIRI and panitumumab). He exhibited a good postoperative course and was discharged on the 12th postoperative day. After 7 months of surgery, no recurrence was observe; and urinary incontinence seen immediately after surgery gradually improved.

[A Case of Late Recurrence of Anal Canal Carcinoma after Surgery, Discovered following the Diagnosis of a Subcutaneous Tumor in the Perineal Region].

We present an 82-year-old male patient who underwent laparoscopic abdominal perineal rectal amputation and D3 lymph node dissection, including left inguinal lymph node dissection for anal canal carcinoma. Left inguinal lymph node metastasis was positive, and pT1bN2aM0, pStage Ⅲa was the final pathological diagnosis. He underwent 8 courses of capecitabine plus oxaliplatin therapy as adjuvant chemotherapy. He was examined without recurrence for 5 years postoperatively. However, he awared a perineal subcutaneous tumor and was transferred to our hospital for further examination and treatment 6 years postoperatively. Recurrence after anal canal carcinoma surgery was diagnosed based on a needle biopsy, and perineal subcutaneous tumor resection was performed. This is a rare case of late postoperative recurrence of anal canal carcinoma, which was detected due to a perineal subcutaneous tumor 6 years after surgery for anal canal carcinoma.

[A Case of Sigmoid Colon Cancer with Simultaneous Solitary Adrenal Metastasis Refractory to Preoperative Diagnosis].

A 72-year-old man was referred to our urology department due to a giant adrenal tumor detected by computed tomography( CT). Endocrine screening showed that cortisol, renin, aldosterone, adrenaline, and noradrenaline levels were all normal, and there was no evidence of adrenal hyperfunction. The adrenal tumor was so large that we suspected malignancy. Contrast-enhanced CT of the abdomen was performed for qualitative diagnostic purposes, and showed wall thickening of the sigmoid colon extending for approximately 6 cm. Lower gastrointestinal endoscopy was performed and revealed a full circumferential type 2 tumor in the sigmoid colon. Biopsy results showed intermediate differentiated ductal adenocarcinoma. Tumor markers were as follows: CEA 23.1 ng/mL, CA19-9 962 U/mL. The adrenal tumor was suspected of being malignant due to its size, but imaging examinations did not lead to a diagnosis of primary or metastatic disease. There were no tumors other than those in the sigmoid colon and adrenal glands. Since complete resection was deemed possible, sigmoid colon resection and combined left adrenalectomy were performed for both a diagnosis and treatment. A histopathological examination revealed that the histology of the adrenal tumor resembled that of colorectal cancer, leading to a diagnosis of left adrenal metastasis from sigmoid colon cancer.

[A Case of Advanced Recurrent Rectal Cancer Successfully Treated by Rechallenge Therapy with an Anti-Epidermal Growth Factor Receptor(EGFR)Drug].

The patient was a 75-year-old man who had undergone potentially curative surgery for Stage Ⅲb rectal cancer followed by resection of liver metastases. Two years after the resection of liver metastases, lung and remnant liver metastases were found. He received chemotherapy for unresectable metastatic tumors. Based on the findings of molecular and pathological examinations(RAS: wild type; BRAF: wild type; MSI: negative; HER2: negative), the following chemotherapy regimens were administered: first-line, FOLFIRI plus panitumumab(PANI); second-line, mFOLFOX6; third-line, trifluridine/tipiracil; fourth- line, regorafenib. After fourth-line treatment, he was judged to have disease progression due to the increase in his lung and liver metastases and the elevation of tumor markers. All standard regimens were refractory, but the Eastern Cooperative Oncology Group performance status was zero and a liquid biopsy for RAS still showed wild type. Therefore, rechallenge therapy with anti-epidermal growth factor receptor(EGFR)drugs, cetuximab(CET)and irinotecan(IRI), was administered 13 months after the final course of FOLFIRI plus PANI treatment. After 4 courses of CET plus IRI, the size of the 2 metastatic tumors markedly decreased and his tumor marker levels normalized.

The impact of the surgical Apgar score on oncological outcomes in patients with colorectal cancer: a propensity score-matched study.

BACKGROUND: The surgical Apgar score (SAS) predicts postoperative complications (POCs) following gastrointestinal surgery. Recently, the SAS was reported to be a predictor of not only POCs but also prognosis. However, the impact of the SAS on oncological outcomes in patients with colorectal cancer (CRC) has not been fully examined. The present study therefore explored the oncological significance of the SAS in patients with CRC, using a propensity score matching (PSM) method. METHODS: We retrospectively analyzed 639 patients who underwent radical surgery for CRC. The SAS was calculated based on three intraoperative parameters: estimated blood loss, lowest mean arterial pressure, and lowest heart rate. All patients were classified into 2 groups based on the SAS (≤6 and >6). The association of the SAS with the recurrence-free survival (RFS), overall survival (OS), and cancer-specific survival (CSS) was analyzed. RESULTS: After PSM, each group included 156 patients. Univariate analyses revealed that a lower SAS (≤6) was significantly associated with a worse OS and CSS. A multivariate analysis revealed that the age ≥75 years old, ASA-Physical Status ≥3, SAS ≤6, histologically undifferentiated tumor type, and an advanced pStage were independent factors for the OS, and open surgery, a SAS ≤6, histologically undifferentiated tumor type and advanced pStage were independent factors for the CSS. CONCLUSIONS: A lower SAS (≤6) was an independent prognostic factor for not only the OS but also the CSS in patients with CRC, suggesting that the SAS might be a useful biomarker predicting oncological outcomes in patients with CRC.

Usefulness of the skeletal muscle index in postoperative ileus of colorectal cancer patients: a retrospective cohort study.

BACKGROUND: Postoperative complications of colorectal cancer mainly include infections (surgical site infection, remote infection, etc.), post-operative ileus (POI), and anastomosis leakage. POI reportedly prolongs the hospital stay and increases medical costs. Therefore, predicting POI is very important. There have been some reports on the relationships between sarcopenia and postoperative complications in colorectal cancer patients, but none have been limited to POI. We therefore conducted a retrospective clinical study with a logistic regression analysis to confirm the risk factors for ileus after colorectal cancer surgery. METHODS: We retrospectively analyzed 213 patients who underwent elective oncological colorectal surgery for colorectal cancer from November 2017 to July 2021. The skeletal muscle mass (SMM, kg) was estimated using a whole-body bioelectrical impedance analysis (BIA), and the skeletal muscle index (SMI) was calculated as the SMM/height2. We divided all patients into 2 groups based on a low SMI (male < 8.958 kg/m2, female < 8.443 kg/m2) or normal SMI. Preoperative and intraoperative factors as well as, postoperative outcomes were then compared between the two groups. RESULTS: The median (range) age of the 213 included patients was 72.0 (33-91) years old. Complications were noted in 96 patients (45.1%), including 21 (9.9%) with POI. There were 68 (31.9%) low SMI patients. POI occurred significantly more frequently in low SMI patients (19.1%) than in normal SMI patients (5.5%) (p = 0.005). In the multivariate analysis, bleeding (p = 0.039) and a low SMI (p = 0.031) were significantly associated with POI. In addition, a propensity score matching analysis was performed to further reduce the selection bias. As a result, a low SMI was the only independent POI predictor among the 78 matched cases. CONCLUSION: A preoperative low SMI in colorectal cancer patients was considered a risk factor for POI.

[A Case Report of Psoas Abscess Formation Caused by Mucinous Cystadenocarcinoma].

We report a rare case of psoas abscess formation caused by mucinous cystadenocarcinoma. A 65-year-old women was admitted to our hospital for treatment for iliopsoas abscess. She presented with standing difficulty and her laboratory data showed an increased level of leukocytes. CT scan demonstrated an abscess formation in iliopsoas muscle. Colonoscopy showed an ulcer on her cecum. Although percutaneous drainage was performed on the first day, the abscess relapsed repeatedly. Ileocolectomy was performed on post admission day 29. Abscess drainage continued after the operation, the patient was discharged on postoperative day 34. Pathological examination revealed mucinous cystadenocarcinoma on the cecal tumor. Total 8 cycles of FOLFOX6 was performed as adjuvant chemotherapy. The patient has been survived for 20 months with no recurrence.

Asporin Expression on Stromal Cells and/or Cancer Cells Might Be A Useful Prognostic Marker in Patients with Diffuse-Type Gastric Cancer.

BACKGROUND: Asporin (ASPN), a member of the proteoglycan family, has been shown to have a close correlation with cancer progression. It is not known whether ASPN is an oncogenic driver or a tumor suppressor in human gastric cancer. We sought herein to determine the relationship between ASPN expression and clinicopathological features of gastric cancer. PATIENTS AND METHODS: A total of 296 gastric cancer patients (diffuse type, n = 144; intestinal type, n = 152) were enrolled. The ASPN expression level in each case was analyzed by immunohistochemistry. RESULTS: ASPN was mainly found on stromal cells, especially on fibroblasts in tumor stroma, i.e., cancer-associated fibroblasts. The ASPN expression on either cancer cells or stromal cells was significantly high in macroscopic scirrhous-type tumors (p < 0.001) and histologically abundant stroma-type tumors (p < 0.001). Interestingly, a Kaplan-Meier survival curve of the 144 cases of diffuse-type gastric cancer revealed a significantly poorer prognosis in patients with ASPN-positive expression (p = 0.043; log rank) compared to those with ASPN-negative expression, but the prognoses were not significantly different in these subgroups of the 152 cases of intestinal-type gastric cancer. A multivariate analysis with respect to overall survival showed that ASPN expression on stromal cells and/or cancer cells was significantly correlated with overall survival in patients with diffuse-type gastric cancer (p = 0.041). CONCLUSION: In gastric cancer, ASPN was expressed mainly on stromal cells and partially on cancer cells. ASPN expression on stromal cells and/or cancer cells might be a useful prognostic marker in patients with diffuse-type gastric cancer.

[A Case of Neuroendocrine Carcinoma Originating from the Papilla of Vater].

A woman in her late 70s with fatigue, nausea, and epigastric discomfort was found to have a tumor at the papilla of Vater through endoscopy. We performed subtotal stomach-preserving pancreaticoduodenectomy with regional lymph node dissection. The immunohistological analysis showed positive staining for chromogranin A, synaptophysin, and CD56. The definitive diagnosis was neuroendocrine carcinoma of the papilla of Vater. Although the patient declined adjuvant chemotherapy, she had to start chemotherapy with carboplatin and etoposide because multiple liver metastases, lymph node metastasis, and peritoneal dissemination occurred 6 months after surgery. We performed 6 courses of chemotherapy. However, progressive disease(PD)was assessed, and she died of cancer 13 months after the surgery. The prognosis of the disease is poor when surgery alone is performed. Adjuvant chemotherapy, in addition to surgery, may be necessary.

[A Case of Hyperammonemic Encephalopathy following mFOLFOX6 plus Panitumumab Therapy for Rectal Cancer].

An 80-year-old man underwent laparoscopic rectal high anterior resection with perineal dissemination for the management of RS rectal cancer. Following the diagnosis of RS rectal cancer with muc, pT4a, N3(14/15), M1c, P1, pStage Ⅳc, RAS/BRAF: wild type, treatment was initiated with mFOLFOX6 plus panitumumab(Pmab). Laboratory examination on admission revealed mild renal dysfunction(Cr 1.45 mg/dL). The patient became confused on day 3 of chemotherapy(JCS Ⅲ-200). Furthermore, laboratory findings revealed a serum ammonia level of 338µg/dL. He was diagnosed with 5-FU- induced hyperammonemic encephalopathy. Discontinuation of high-dose 5-FU and branched-chain amino acid solutions improved his mental status and decreased serum ammonia levels. We switched his chemotherapy regime to CPT-11 plus Pmab, but it was discontinued after 1 course on his request.

[A Case of the Large Rectal GIST Treated by Laparoscopic Anus Preserving Operation after Neoadjuvant Therapy with Imatinib Mesylate].

A 50s old woman admitted to our hospital with anal pain, who was diagnosed as rectal gastrointestinal stromal tumor (GIST). After neoadjuvant therapy with imatinib mesylate for 6 months, the tumor reduced by 75% from its original size and anus preserving operation(low anterior resection)was performed. After operation adjuvant therapy with imatinib mesylate was performed for 2 years and 6 months. The patient is alive without recurrence 5 years after surgery. It is suggested that neoadjuvant therapy with imatinib mesylate is useful and safety for large rectal GIST, from the standpoint of anal preservation.