Kouki Wakata's research while affiliated with Sasebo City General Hospital and other places

Background/aim: We aimed to assess the risk factors for postoperative complications and long-term outcome of patients aged ≥80 years after curative resection for gastric cancer (GC). Patients and methods: Patients aged ≥80 years who underwent curative gastrectomy for stage I-III GC between 2013 and 2020 were included. Clinical factors were retrospectively analyzed. Results: Of all 109 patients, 29 (26.6%) had 33 postoperative complications (Clavien-Dindo grade ≥2). The rate of postoperative complications was higher in those with greater blood loss (≥170 ml, p<0.001). In multivariate analysis, greater blood loss was confirmed as an independent predictor of postoperative complications (p<0.001). The 30-day, 180-day, 1-year, and 3-year cumulative overall survival rates were 100%, 97.0%, 91.6%, and 74.7%, respectively. Multivariate analysis showed postoperative complications (p=0.014) and low prognostic nutritional index (PNI, p=0.044) were independent prognostic factors for poor overall survival. Conclusion: Performing operations with less bleeding is important to reduce postoperative complications. According to the analysis of long-term survival, patients who experience postoperative complications and patients with a low preoperative PNI require special attention in the follow-up period. Nutritional support should be considered in patients with malnutrition.

Schwannomas that occur in the retroperitoneal cavity are rare. We herein report a patient who underwent safe laparoscopic resection by using a preoperative 3D computed tomography (CT) image and a fluorescent ureteral stent during the surgery. A 47-year-old man presented with left lower abdominal pain. CT showed a 10-cm continuous retroperitoneal tumor originating at the third lumbar nerve in the lower left abdomen. Schwannoma was suspected. We underwent laparoscopic resection of the tumor guided by 3D images obtained preoperatively. A fluorescent ureteral stent was implanted during the surgery to improve visibility and protect the left ureter. The resection was completed without injury of other organs and vessels. The patient was discharged on postoperative Day 5. By performing a preoperative simulation using 3D CT images, we could anticipate the anatomical findings and easily identify them intraoperatively. In addition, the fluorescent ureteral stent provided visual support, thereby contributing to safe surgery.

Background/objective With increased life expectancy, the incidence of colorectal cancer in oldest-old patients has been rising. Advanced age is a risk factor for adverse outcomes after surgery. This study aimed to evaluate the short- and long-term outcomes of curative resection for colorectal cancer in nonagenarians. Methods Patients who had undergone curative resection for colorectal cancer (CRC) at Stage I to III from January 2010 to December 2019 were included. Cases of emergent surgery were excluded. The clinical characteristics were documented retrospectively, and factors affecting the long-term outcome were analyzed using multivariate analysis. Results Fifty patients met the selection criteria. Most of them were women (58.0%), and the median age was 92 years. Among these patients, 29 (58.0%) had a poor performance status (ASA-PS≥3). Laparoscopic surgery was performed in 42.0% of the patients, and 50% of the patients had postoperative complications classified as Clavien–Dindo grade 2 or severer, including 3 patients (6.0%) with grade 3 disease. No postoperative mortality occurred. The 30-day, 180-day, 1-year, 3-year and 5-year survival rates were 100%, 80.4%, 71.0%, 46.3%, and 33.8%, respectively. Multivariate analysis showed that a preoperative poor performance status (ASA-PS≥3) (HR: 3.067; 95% CI: 1.220–7.709; p = 0.017) was an independent prognostic factor for OS. Conclusion Curative elective resections for CRC in nonagenarians were performed safely without postoperative mortality. The preoperative performance status was significantly associated with OS after curative elective resection of colorectal cancer in nonagenarians. Our results suggest that excellent long-term outcomes can be achieved in a selected group with a good performance status.

Objective: Resection is usually recommended for locally recurrent rectal cancer (LRRC) for which R0 resection is possible, but its suitability varies by individual patient risk. Here, we report outcomes of resected LRRC in our hospital. Methods: We retrospectively evaluated short- and long-term results of 33 patients who underwent resections for LRRC from January 2003 to December 2019. Results: At the initial surgeries for these 33 patients, their disease stages at that time were Stage I: n=2, Stage II: n=12, Stage III: n=11, Stage IV: n=6, and unknown: n=2. Patients with Stage IV disease at their initial surgeries underwent radical one-step or two-step procedures. Metastasis to other organs was observed in 5 patients at the their initial LRRC diagnoses. At the LRRC surgeries, 7 patients received palliative surgeries; 26 received intent-to-treat resections, of which 17 were R0 resections. All-grade postoperative complications were observed in 11 patients, including 1 surgery-related death. Five-year overall survival rates were all cases: 38.4%; R0 group: 52.3%, R1 or R2 group: 19.4%, and palliative surgery group: 0%. The R0 group thus had significantly better prognosis than other patients (P = 0.0012). Eleven patients in the R0 group (64.7%) suffered re-recurrences but some patients achieved long-term survival through chemotherapy, radiation therapy, and surgery for metastasis to other organs, even after re-recurrence. Conclusion: Long-term prognosis after surgery for LRRC was significantly better for patients with R0 margins. Multimodal treatments may greatly improve survival for patients who suffer re-recurrences after local recurrence resections.

Background Hemostasis is very important for a safe surgery, particularly in endoscopic surgery. Accordingly, in the last decade, vessel-sealing systems became popular as hemostatic devices. However, their use is limited due to thermal damage to organs, such as intestines and nerves. We developed a new method for safe coagulation using a vessel-sealing system, termed flat coagulation (FC). This study aimed to evaluate the efficacy of this new FC method compared to conventional coagulation methods. Methods We evaluated the thermal damage caused by various energy devices, such as the vessel-sealing system (FC method using LigaSure™), ultrasonic scissors (Sonicision™), and monopolar electrosurgery (cut/coagulation/spray/soft coagulation (SC) mode), on porcine organs, including the small intestine and liver. Furthermore, we compared the hemostasis time between the FC method and conventional methods in the superficial bleeding model using porcine mesentery. Results FC caused less thermal damage than monopolar electrosurgery’s SC mode in the porcine liver and small intestine (liver: mean depth of thermal damage, 1.91 ± 0.35 vs 3.37 ± 0.28 mm; p = 0.0015). In the superficial bleeding model, the hemostasis time of FC was significantly shorter than that of electrosurgery’s SC mode (mean, 19.54 ± 22.51 s vs 44.99 ± 21.18 s; p = 0.0046). Conclusion This study showed that the FC method caused less thermal damage to porcine small intestine and liver than conventional methods. This FC method could provide easier and faster coagulation of superficial bleeds compared to that achieved by electrosurgery’s SC mode. Therefore, this study motivates for the use of this new method to achieve hemostasis with various types of bleeds involving internal organs during endoscopic surgeries.

Introduction and importance Granulocyte colony-stimulating factor (G-CSF)-producing intrahepatic cholangiocarcinoma is rare. Surgical cases with postoperative clinical course have rarely been reported. Case presentation A 63-year-old woman complained upper abdominal pain. Computed tomography (CT) showed intrahepatic mass measuring 9 × 9 × 9 cm in the left lateral segment. ¹⁸F-fluorodeoxyglucose positron emission tomography (FDG-PET) showed high uptake by the tumor, with diffuse uptake in the bone marrow. An extended left lobectomy was performed to achieve complete resection. Histopathological examination showed poorly differentiated adenocarcinoma with no lymph node metastasis. Immunohistochemical analysis revealed that tumor cells produced G-CSF. After chemotherapy with S-1 regimen at 10 months after the operation, CT and FDG-PET detected lymph node metastasis in the peri-duodenal area and left kidney metastasis, with no FDG uptake in the bone marrow. Serum G-CSF was normal. Combination chemotherapy with gemcitabine plus cisplatin was administered, and, 12 months after liver resection, metastases were enlarged and FDG uptake in the bone marrow was detected again. Serum G-CSF was elevated at 71.6 pg/mL. The patient was enrolled in a clinical trial of chemotherapy with another regimen and was alive at 19 months after liver resection. Clinical discussion Because of rapid progression, rapid diagnosis and resection are important. FDG uptake in the bone marrow is characteristic in G-CSF producing tumor. In this case, FDG uptake in the bone marrow reappeared after the enlargement of recurrent lesions, followed by tumor enlargement. Conclusion FDG-PET was useful for differential diagnosis and to assess tumor viability and determine the surgical indication.

Background/aim: Perforation and postoperative complications have a negative effect on long-term outcomes in patients with colorectal cancer (CRC). The aim of this study was to evaluate the clinical factors with special reference to postoperative complications predicting the long-term outcome in those for whom curative resection for perforated CRC was performed. Patients and methods: Patients who underwent curative resection for perforated CRC at stage II or III from April 2003 to March 2020 were included. Clinical factors were retrospectively analyzed. Results: Forty-four patients met the selection criteria. The 30-day mortality rate was 4.5% and the complication rate was 47.7%. Excluding 30-day mortality, five-year recurrence-free survival (RFS) and overall survival (OS) were 62.3% and 73.6%, respectively. Multivariate analysis showed that postoperative complications (p=0.005) and pT4 pathological factor (p=0.009) were independent prognostic factors for RFS. Only postoperative complications (p=0.023) were an independent prognostic factor for OS. Conclusion: Postoperative complications were significantly associated with RFS and OS, and pT4 was associated with RFS. The prevention and management of postoperative adverse events may be important for perforated CRC.

Introduction Lung cancer is one of the most common cancers. On the other hand, lung cancer metastasis to the appendix is extremely rare, and in many cases it has been diagnosed with the onset of acute perforating appendicitis. Presentation of case An 85-year-old man with fever and abdominal pain visited our hospital. He had a history of squamous cell carcinoma of the left upper and lower lobes, metastasis to the ipsilateral lung and femur. CT showed that a finding of acute perforating appendicitis, emergency cecal resection was performed. Examination of the resected specimen showed that the appendix was thickened overall, with a white nodular structure at the root and a perforation in the middle. The final diagnosis was acute perforating appendicitis caused by metastatic squamous cell carcinoma from the lung. The patient had no particular problems during the postoperative course. Discussion A PubMed search was performed, this appears to be the first reported case of appendiceal metastasis of squamous cell carcinoma of the lung. Since squamous cell carcinoma of the lung has a stronger tendency for local extension than other histological types, perforating appendicitis due to distant metastasis to the abdominal organs and metastasis to the appendix was reported as a very valuable case. Conclusion Because the progression of concomitant or secondary appendicitis is rapid, we recommend frequent imaging modalities, prophylactic appendectomy be considered for patients who also have lung cancer and imaging findings show suspected metastasis to the appendix.

To prevent postoperative pancreatic fistulas during suprapancreatic lymph node dissection in laparoscopic gastrectomy, we have adopted a surgical approach that avoids direct compression of the pancreas since January 2017. Between January 2011 and December 2018, 178 patients underwent laparoscopic gastrectomy with placement of an abdominal drain for gastric cancer at our institution. The patients were divided into two groups, with 124 patients in the compression group (until December 2016) and 54 patients in the non-compression group (since January 2017). The patients' background characteristics, clinicopathological factors, and surgical outcomes were then compared retrospectively. The drainage fluid amylase levels were lower in the non-compression group than in the compression group on postoperative day 1 ; in particular, they were significantly lower on postoperative day 3 (p=0.001). No patient developed postoperative pancreatic fistula (Clavien-Dindo Grade ≥2) in the non-compression group. A surgical approach to avoid direct compression of the pancreas in laparoscopic gastrectomy is a useful method to prevent postoperative pancreatic fistulas.

Introduction: Tracheal adenoid cystic carcinoma (ACC) is rare and accounts for <1% of all lung cancers. Although ACC is classified as a low-grade tumor, metastases are frequently identified in the late period. Extrapulmonary metastases are rare, and their resection has rarely been reported. Presentation of case: Case 1: A 77-year-old man underwent tracheal resection for ACC with postoperative radiation (60 Gy) 14 years before (at the age of 63). He underwent two subsequent pulmonary resections for metastases. Fourteen years after the first operation, he underwent extended right posterior segmentectomy with resection of segment IV and radiofrequency ablation for metastases of ACC to the liver. He was diagnosed with metastases to the kidney with peritoneal dissemination 4 years after the liver resection and died of pneumonia 2 years later. Case 2: A 53-year-old woman underwent a two-stage operation involving tracheal resection for ACC and partial resection of liver segments II and V for metastases of ACC to the liver. The tracheal margin was histopathologically positive. Postoperative radiation was performed, and she was tumor-free for 10 months after the liver resection. Discussion: Complete resection of tracheal ACC provides better survival. Radiotherapy is also recommended. However, the optimal treatment for metastases of ACC is unclear, especially because liver resection for metastases of tracheal ACC is rarely reported. Our two cases of metastases of tracheal ACC were surgically managed with good outcomes. Conclusion: Liver resection for metastases of tracheal ACC may contribute to long survival.