Explainable artificial intelligence prediction-based model in laparoscopic liver surgery for segments 7 and 8: an international multicenter study.

BACKGROUND: Artificial intelligence (AI) is becoming more useful as a decision-making and outcomes predictor tool. We have developed AI models to predict surgical complexity and the postoperative course in laparoscopic liver surgery for segments 7 and 8. METHODS: We included patients with lesions located in segments 7 and 8 operated by minimally invasive liver surgery from an international multi-institutional database. We have employed AI models to predict surgical complexity and postoperative outcomes. Furthermore, we have applied SHapley Additive exPlanations (SHAP) to make the AI models interpretable. Finally, we analyzed the surgeries not converted to open versus those converted to open. RESULTS: Overall, 585 patients and 22 variables were included. Multi-layer Perceptron (MLP) showed the highest performance for predicting surgery complexity and Random Forest (RF) for predicting postoperative outcomes. SHAP detected that MLP and RF gave the highest relevance to the variables "resection type" and "largest tumor size" for predicting surgery complexity and postoperative outcomes. In addition, we explored between surgeries converted to open and non-converted, finding statistically significant differences in the variables "tumor location," "blood loss," "complications," and "operation time." CONCLUSION: We have observed how the application of SHAP allows us to understand the predictions of AI models in surgical complexity and the postoperative outcomes of laparoscopic liver surgery in segments 7 and 8.

Prognostic Factors and Lymph Node Metastasis Patterns of Primary Duodenal Cancer.

BACKGROUND: The effectiveness and extent of regional lymph node dissection in primary duodenal cancer (DC) remains unclear. This study aimed to analyze the prognostic factors and lymph node metastasis (LNM) patterns in DC. METHODS: Fifty-three patients who underwent surgical resection for DC between January 1998 and December 2018 at two institutions were retrospectively analyzed. Univariate and multivariate analyses were performed on the prognostic factors of resected DC. Moreover, the relationships between depth of tumor invasion and incidence of LNM and between tumor location and LNM stations were analyzed. RESULTS: The five-year survival rate of the study population was 68.9%. Multivariate survival analysis demonstrated that histologic grade G2-G4, presence of LNM, pT3-4, and elevated preoperative CA19-9 were the independent poor prognostic factors. No patient with pTis-T2 had LNM. On the other hand, LNM was found in 70% of patients with pT3-4. Among 36 patients who underwent pancreaticoduodenectomy (PD), LNM around the pancreatic head was observed, regardless of the duodenal cancer site, including the duodenal bulb and the third to the fourth portion. CONCLUSIONS: Histologic grade G2-G4, presence of LNM, pT3-T4, and elevated preoperative CA19-9 were the independent poor prognostic factors in patients with resected DC. Our results suggested that lymph node dissection could be omitted for DC Tis-T1a. Moreover, based on the high frequency of LNM in T3-4 cases, PD with lymph node dissection in the pancreatic head region was considered necessary for T3-4 DC at any site.

[Synchronous Double Primary Non-B, and Non-C Intrahepatic Cholangiocarcinoma and Hepatocellular Carcinoma-A Case Report].

A 78-year-old man without hepatitis virus B or C underwent right hemi-hepatectomy and lymph node dissection for a tumor 5 cm in diameter located in the hepatic hilum of the posterior segment of the liver with portal vein thrombi extending into the main portal trunk and a tumor 1.5 cm in diameter in the peripheral side of segment 5 of the liver. Histopathologically, the former was diagnosed as intrahepatic cholangiocarcinoma and the latter as hepatocellular carcinoma(HCC). Five months after the surgery, intrahepatic and lymph node metastases were diagnosed based on computed tomography(CT); therefore, chemotherapy with S-1 for 3 months and gemcitabine and cisplatin(GC)for 5 months was administered, after which the metastatic lesions were not detected. Nineteen months after the surgery, partial resection of segment 2 of the liver was performed for a tumor 3 cm in diameter, which was diagnosed as HCC histopathologically. Two years after the second surgery, 2 recurrent nodules in the liver in segments 3 and 4 were detected on CT. Platinum-based hepatic arterial infusion chemotherapy(HAIC)and transcatheter arterial chemoembolization(TACE)were performed, and chemotherapy with GC was then administered for 7 months. For a new tumor detected in segment 1 in the liver, TACE was performed 17 months after initial HAIC. Seventy-four months after the initial surgery, 5 new nodules less than 1 cm in diameter were detected, and chemotherapy with sorafenib was administered for 5 months, after which the patient died of coronavirus disease 2019.

[Locally Advanced Pancreatic Cancer Treated with Two-Staged Pancreaticoduodenectomy after Laparoscopic Median Arcuate Ligament Section-A Case Report].

A 76-year-old male was diagnosed as locally advanced pancreatic cancer because abdominal CT scan revealed a pancreatic head tumor with involvement of the proper hepatic artery. Gemcitabine plus nab-paclitaxel was initiated, but was discontinued because interstitial pneumonia was occurred. The treatment was switched to S-1 therapy and achieved stable disease for 22 months. Therefore, conversion surgery was scheduled. Because stenosis of the celiac artery origin due to median arcuate ligament(MAL)compression and dilatation of pancreatoduodenal artery arcade were observed, laparoscopic MAL section was performed. The patient was discharged on postoperative day 5 without complications. Postoperative CT scan revealed no stenosis of the celiac artery origin and disappearance of dilatation of pancreatoduodenal artery arcade. On postoperative day 14, subtotal stomach-preserving pancreaticoduodenectomy(PD)with portal vein resection was performed. The patient was discharged on postoperative day 19 without complications. Two-staged PD after MAL section make possible to evaluate blood flow accurately and select an appropriate operative method. Laparoscopic MAL section is minimally invasive and may be useful for two-staged PD in patients with celiac axis stenosis.

[A Case of pStage IB Gastric Cancer Relapsed on Both Pleura and Peritoneum Eight Year after Radical Gastrectomy].

An 86-year-old man presented with upper abdominal pain and was diagnosed with type 0-Ⅲ gastric cancer located at the posterior wall of the upper stomach by upper gastrointestinal endoscopy. Laparoscopic total gastrectomy(D1+)was performed for gastric cancer of cStage Ⅰ. As final pathological diagnosis was pT2N0(0/27)M0H0P0CY0, pStage ⅠB, adjuvant chemotherapy was not administrated. The patient has been alive with no recurrence for 5 years after surgery. 8 years and 1 month after procedure, he visited our hospital with chief complaint of abdominal distention and anorexia. Chest and abdominal CT showed pleural fluid and ascites, but PET-CT could not detect any sites of recurrence. Cytopathology and cell blocks by immunohistochemical staining of ascites proved recurrence of previous gastric cancer. Any treatment was rejected, and the patient died 3 months after recurrence and 8 years and 4 months after gastrectomy. Late recurrence on both pleura and peritoneum of gastric cancer is very rare. We report a case of pStage ⅠB gastric cancer relapsed on both pleura and peritoneum 8 year after radical gastrectomy.

[A Case of Recurrent Gastric Cancer of Multiple Organ Metastasis with Long-Term Survival Due to Multimodal Treatment].

A 67-year-old man was introduced to examine for abnormal findings in physical examination. Upper gastrointestinal endoscopy detected the 3 lesions and diagnosed multiple gastric cancers with biopsy. Laparoscopic total gastrectomy was performed and final pathological diagnosis was pT2N1M0, pStage ⅡA with HER2 positive(3+). Adjuvant chemotherapy was not administrated. CT findings 6 months after procedure showed 2 liver metastases(S6, S7)and laparoscopic partial liver resection was performed. Pathological findings proved the metastasis of previous gastric cancer. Although adjuvant chemotherapy of S-1 was started 2 months after hepatectomy, CT findings showed second recurrences in liver and right adrenal gland. Chemotherapy was changed to S-1 plus cisplatin(SP)plus trastuzumab. AS these recurrence sites and ascites could not be detected by CT after 6 courses, therapeutic effect was judged as clinical CR(cCR)and SP plus trastuzumab was stopped due to side effect. Since then, regular follow-up CT showed preservation of status of cCR without chemotherapy and he has been alive without recurrence for 8 years and 9 months after gastrectomy. We report a case of recurrent gastric cancer of multiple organ metastasis with long-term survival due to multimodal treatment.

[Prognostic Analysis of Colorectal Cancer Patients by the Controlling Nutritional Status(CONUT)Score].

We examined the controlling nutritional status(CONUT)score and the long-term prognosis of colorectal cancer surgery cases. We retrospectively examined the prognosis of colorectal cancer patients who underwent surgery between January 2013 and December 2015. We targeted 449 patients who were able to calculate the CONUT score. A total of 266 patients (59.2%)had normal nutritional status(1 or less)and 183 patients(40.8%)had mildly poor or worse nutritional status (2 or more). The CONUT score was calculated through preoperative blood tests. The relationship between the CONUT score and overall survival was examined in the low and high groups. Overall survival was significantly shorter in the high group but relapse-free survival did not differ significantly between the 2 groups. There was no difference in cancer-specific survival between the 2 groups, but the survival time due to death from other diseases was significantly shorter in the high group. The CONUT score obtained from preoperative blood sampling suggested that the overall survival time was short in the malnourished group, and that it could be used as an index of prognosis due to death from other diseases.

[Short-Term Clinical Outcome of Robotic Surgery for Advanced Rectal Cancer after Neoadjuvant Therapy].

We examined 14 cases who underwent robotic rectal resection with neoadjuvant chemotherapy(NAC)or neoadjuvant chemoradiation therapy(NACRT)for local advanced rectal cancer in our hospital from 2018 June to 2020 December. Two patients underwent NACRT, 12 patients underwent NAC. Sex was 10 males and 4 females. The median age was 66. The surgical procedure was ISR 2 cases, LAR 8 cases, APR 4 cases. The median operation time was 397 minutes and the median blood loss was 73 mL. The histological response grade were Grade 3: 1 case, 2: 7 cases, 1b: 3 cases, and 1a: 3 cases. Surgical margin was negative in all cases. Postoperative complications(≥Clavien-Dindo Grade Ⅲ)required reoperation due to intestinal obstruction in 1 case. Urinary dysfunction was nothing in all cases. Although long-term results such as prognosis and function preservation need to be examined, short-term results of robot-assisted rectal resection after NAC or NACRT were generally good.

[A Case of Robot Assisted Low Anterior Resection for a Patient with Persistent Descending Mesocolon].

Persistent descending mesocolon(PDM)is caused by absence of fusion of the descending colon to the retroperitoneum. A 67-year-old man with bloody stools was diagnosed with rectal cancer on colonoscopy. A computed tomography showed a medial displacement of his descending colon. The preoperative clinical diagnosis was rectal cancer with PDM, and robot assisted low anterior resection was performed. We found that the left-sided colon was shifted to the midline and adhered the cecum and the mesentery of small intestine. Robot assisted surgery enables surgery with the precise adhesiotomy in a stable field. PDM is a relatively rare anatomic abnormality. Character of PDM is adhesion between the left-sided colon and other organs and radially branch from the inferior mesenteric artery. It is important to understand the anatomical characteristics of PDM and to improve on existing surgical procedures to ensure safe robot assisted surgery these patients.

[Short- and Long-Term Surgical Outcomes for Patients with Colorectal Cancer Aged 80 Years or Older].

This study aimed to assess short-term and long-term outcomes and to identify the factors that affect outcomes for patients with colorectal cancer aged 80 years or older. Two hundred patients with colorectal cancer who were underwent resection of the primary tumor between January 2013 and December 2018 were enrolled. Short-term outcomes of elderly patients with poor PS and of those who take antithrombotic agents and of those who were underwent open surgery were poor. Long-term outcomes of elderly patients with high GNRI and of those who were underwent D3 lymph nodes dissection were better. Laparoscopic surgery with D3 lymph nodes dissection for elderly patients who were more than 80 years old should be useful to improve short- and long-term outcomes. GNRI might be a prognostic predictive factor for patients with colorectal cancer aged 80 years or older.

Development of a nomogram to predict outcome after liver resection for hepatocellular carcinoma in Child-Pugh B cirrhosis.

BACKGROUND & AIMS: Treatment allocation in patients with hepatocellular carcinoma (HCC) on a background of Child-Pugh B (CP-B) cirrhosis is controversial. Liver resection has been proposed in small series with acceptable outcomes, but data are limited. The aim of this study was to evaluate the outcomes of patients undergoing liver resection for HCC in CP-B cirrhosis, focusing on the surgical risks and survival. METHODS: Patients were retrospectively pooled from 14 international referral centers from 2002 to 2017. Postoperative and oncological outcomes were investigated. Prediction models for surgical risks, disease-free survival and overall survival were constructed. RESULTS: A total of 253 patients were included, of whom 57.3% of patients had a preoperative platelet count <100,000/mm3, 43.5% had preoperative ascites, and 56.9% had portal hypertension. A minor hepatectomy was most commonly performed (84.6%) and 122 (48.2%) were operated on by minimally invasive surgery (MIS). Ninety-day mortality was 4.3% with 6 patients (2.3%) dying from liver failure. One hundred and eight patients (42.7%) experienced complications, of which the most common was ascites (37.5%). Patients undergoing major hepatectomies had higher 90-day mortality (10.3% vs. 3.3%; p = 0.04) and morbidity rates (69.2% vs. 37.9%; p <0.001). Patients undergoing an open hepatectomy had higher morbidity (52.7% vs. 31.9%; p = 0.001) than those undergoing MIS. A prediction model for surgical risk was constructed (https://childb.shinyapps.io/morbidity/). The 5-year overall survival rate was 47%, and 56.9% of patients experienced recurrence. Prediction models for overall survival (https://childb.shinyapps.io/survival/) and disease-free survival (https://childb.shinyapps.io/DFsurvival/) were constructed. CONCLUSIONS: Liver resection should be considered for patients with HCC and CP-B cirrhosis after careful selection according to patient characteristics, tumor pattern and liver function, while aiming to minimize surgical stress. An estimation of the surgical risk and survival advantage may be helpful in treatment allocation, eventually improving postoperative morbidity and achieving safe oncological outcomes. LAY SUMMARY: Liver resection for hepatocellular carcinoma in advanced cirrhosis (Child-Pugh B score) is associated with a high rate of postoperative complications. However, due to the limited therapeutic alternatives in this setting, recent studies have shown promising results after accurate patient selection. In our international multicenter study, we provide 3 clinical models to predict postoperative surgical risks and long-term survival following liver resection, with the aim of improving treatment allocation and eventually clinical outcomes.

Validation and performance of three-level procedure-based classification for laparoscopic liver resection.

BACKGROUND: A procedure-based laparoscopic liver resection (LLR) classification (IMM classification) stratified 11 different LLR procedures into 3 grades. IMM classification assessed the difficulty of LLR differently than an index-based LLR classification (IWATE criteria), which scored each procedure on an index scale of 12. We validated the difference of 3 IMM grades using an external cohort, evaluated the IMM classification using the scores of the IWATE criteria, and compared the performance of IMM classification with the IWATE criteria and the minor/major classification. METHODS: Patients undergoing LLR without simultaneous procedures were selected from a prospectively maintained database at the Institut Mutualiste Montsouris (IMM cohort) and from the database of 43 Japanese institutions (JMI cohort). Surgical and postoperative outcomes were evaluated according to the 3 IMM grades using the JMI cohort. The 11 LLR procedures included in the IMM classification were scored according to the IWATE criteria. The area under the curves (AUCs) for surgical and postoperative outcomes were compared. RESULTS: In the JMI (n = 1867) cohort, operative time, blood loss, conversion rate, and major complication rate were significantly associated with a stepwise increase in grades from I to III (all, P < 0.001). In the IMM (n = 433) and JMI cohorts, IMM grades I, II, and III corresponded to three low-scoring, two intermediate-scoring, and six high-scoring LLR procedures as per the IWATE criteria, respectively. Mean ± standard deviation among the IMM grades were significantly different: 3.7 ± 1.4 (grade I) versus 7.5 ± 1.7 (grade II) versus 10.2 ± 1.0 (grade III) (P < 0.001) in the IMM cohort and 3.6 ± 1.4 (grade I) versus 6.7 ± 1.5 (grade II) versus 9.3 ± 1.4 (grade III) (P < 0.001) in the JMI cohort. The AUCs for surgical and postoperative outcomes are higher for the 3-level IMM classification than for the minor/major classification. CONCLUSIONS: The difference of 3 IMM grades with respect to surgical and postoperative outcomes was validated using an external cohort. The 3-level procedure-based IMM classification was in accordance with the index-based IWATE criteria. The IMM classification performed better than the minor/major classification for stratifying LLR procedures.

[Clinical Significance of Preoperative Chemotherapy for Advanced Colorectal Cancer].

We examined 22 cases who underwent preoperative chemotherapy in our hospital from 2013 April to 2018 December. Seven patients were treated as neoadjuvant chemotherapy(NAC). Out of 15 patients with unresectable diseases before chemotherapy, 6 patients were able to R0 resection after chemotherapy(conversion). Although only one patients was underwent RM1 resection, the other patients were underwent RM0 resection. The median overall survival was 42 months in NAC group, 28 months in conversion group, and 17 months in palliative resection group, respectively. Recurrence was observed in 1 patient in NAC group, however, all patients had recurrent disease in conversion group. In this study, although further examination should be done according to the clinical significance of preoperative chemotherapy, preoperative chemotherapy may be carried out without severe adverse event and severe postoperative complication.

[Laparoscopic Resection of Solitary Lymph Node Metastasis of Hepatocellular Carcinoma after Transcatheter Arterial Chemoembolization and Percutaneous Locoregional Therapies].

A 75-year-old woman underwent transcatheter chemoembolization(TACE)for 2 small hepatocellular carcinoma(HCC) lesions associated with severe alcoholic liver cirrhosis that necessitated management for ascites. Over 5 years after the initial TACE, she received multidisciplinary therapies with TACE, transcatheter arterial infusion of anticancer agents, percutaneous ethanol injections, or percutaneous radiofrequency ablation performed on 5 occasions for small recurrent HCC lesions. Computed tomography performed after the last therapy for HCC revealed a solitary lymph node swelling(39 mm in diameter) around the common hepatic artery. Magnetic resonance imaging performed 3 months later revealed that the lymph node had enlarged to 45 mm, without recurrence of the primary HCC, and after 4 months, to 60 mm; she then underwent laparoscopic lymph node resection. Histopathological examination of the resected specimen showed HCC metastasis. A recurrent metastatic lymph node(30 mm in diameter)was detected around the common hepatic artery and was resected laparoscopically 17 months postoperatively. Pancreatic head cancer was diagnosed 22 months after the second surgery; however, the patient refused cancer therapy and died 16 months after this diagnosis. No recurrence of the primary HCC or lymph node metastasis was observed over the 38 months after the second surgery.

[A Resected Case for Needle-Tract Implantation after Radiofrequency Ablation to the Hepatocellular Carcinoma].

A 82-year-old female had received radiofrequency ablation for hepatocellular carcinoma(HCC)in segment 2 30 months before surgery. One month before surgery, enhanced CT showed enhanced lesion about 20 mm in diameter in the abdominal wall along the needle-tract. There was no other recurrent lesion including liver. We diagnosed the lesion as needle-tract implantation and she underwent surgical resection of the abdominal rectus muscle and sheath including needle-tract. The pathological findings revealed well differentiated HCC. After the surgery, she underwent transcatheter arterial embolization for the recurrent HCC in segment 3 and segment 4. Twenty one months after the surgery, she has been alive without recurrence. Our case demonstrated that surgical resection of the needle-tract implantation of the HCC is one of the useful therapeutic options for the selected patients.

[Successful Conversion Surgery for Pancreatic Cancer with Sister Mary Joseph's Nodule-A Case Report].

A 66-year-old female with upper abdominal pain was diagnosed the pancreatic tail cancer infiltrating into the stomach and transverse colon by computed tomography(CT). Umbilical metastasis(so called Sister Mary Joseph's nodule)and peritoneal metastases in pouch of Douglas were detected by FDG-PET. The patient was diagnosed as unresectable pancreatic cancer with distant metastases. Thus, she received FOLFIRINOX therapy. After 9 courses of FOLFIRINOX therapy and 15 courses of FOLFIRI therapy, the pancreatic tumor shrunk on CT. In addition, umbilical metastasis and peritoneal metastases disappeared on FDG-PET. Therefore, conversion surgery was scheduled. Fourteen months after the initial treatment, we performed distal pancreatectomy with left adrenalectomy partial gastrectomy, transverse colectomy, and umbilical resection. The patient was discharged 15 days after the operation without serious complications. Histopathological findings revealed the presence of adenocarcinoma infiltrating into the preperitoneal adipose tissue in the umbilicus. Histological therapeutic effect was Grade Ⅰb according to the 7th Edition of the General Rules for the Study of Pancreatic Cancer. Seven months after the operation, local recurrence was showed. The patient is still alive 2 years and 5 months since the initial treatment.

[Pancreatic Cancer with Hemobilia after Biliary Self-Expandable Metallic Stent Placement during Neoadjuvant Chemotherapy-A Case Report].

A 67-year-old woman was diagnosed with borderline resectable pancreatic cancer and obstructive jaundice. A covered self-expandable metallic stent(SEMS)was placed endoscopically. Neoadjuvant chemotherapy with gemcitabine plus nabpaclitaxel was provided. Forty-seven days after the SEMS placement, she presented with hematemesis. Computed tomography revealed migration of SEMS into the small bowel. No pseudoaneurysms were detected. Upper digestive endoscopy demonstrated hemobilia without obvious causes of bleeding in the stomach or duodenum. As hemorrhage recurrence was confirmed in the bile duct, we performed pancreaticoduodenectomy. Thus, bile duct hemorrhage can occur in patients with pancreatic cancer after SEMS placement.

[A Case of Advanced Hepatocellular Carcinoma Successfully Treated with Liver Resection after Administration of Sorafenib].

CASE: A 76-year-old man was referred to our hospital for advanced hepatocellular carcinoma(HCC)with chronic hepatitis type B. Although he underwent right anterior sectionectomy and S3 segmentectomy, multiple recurrences were found in the hepatic remnant after 2 months. Transcatheter arterial chemoembolization(TACE)and transcatheter arterial infusion (TAI)were performed separately. One and a half month after the last TAI, AFP and PIVKA-Ⅱ levels markedly elevated, and multiple early enhancing nodules with portal vein tumor thrombosis were detected on CT. A half dose of sorafenib(400mg/ day)was administered to the patient who was refractory to TACE. Sorafenib was discontinued after 4 weeks because the patient developed general fatigue and anorexia(Grade 3). Furthermore, these adverse events became worse, and ascites appeared. He was hospitalized in the palliative care unit for best supportive care for 3 weeks and also received outpatient treatment for more than 14 months. Fifteen months after discontinuing sorafenib administration, his condition improved dramatically, and CT revealed that the multiple HCC had reduced in size. Moreover, the portal vein tumor thrombosis disappeared. As his performance status and liver function were well preserved, he underwent partial hepatectomy for residual HCC. The patient remains alive without recurrence at 18 months, despite no administration of sorafenib. CONCLUSION: This case demonstrates that sorafenib administration combined with surgical treatment could possibly cure advanced HCC refractory to TACE.

[A Case of Metachronous Liver Metastasis of Gallbladder Cancer Controlled by Liver Resection].

The patient was an 81-year-old woman. She had undergone extended cholecystectomy with lymph node dissection for primary gallbladder cancer. The pathological diagnosis was moderately differentiated tubular adenocarcinoma(pT2, N0, M0, pStage Ⅱ). Eleven months after the initial surgery, dynamic CT revealed a solitary low-enhanced tumor in S5 ofthe liver. As the tumor was detected with abnormal FDG uptake by PET-CT, we diagnosed the patient with a metastatic liver tumor from gallbladder cancer. Although chemotherapy was considered, conservative treatment was selected as the patient did not want to undergo chemotherapy. Therefore, laparoscopic partial liver resection was performed 15 months after the initial surgery with the consideration that no other distant metastasis was found, and tumor markers were within normal ranges. The postoperative course was uneventful, and the patient was discharged 13 days after liver resection without any morbidities. The resected tumor was pathologically diagnosed as a metastatic liver tumor from gallbladder cancer. She has achieved 18 months recurrence free survival after the liver resection without adjuvant chemotherapy. Although liver resection for a metastatic liver tumor from gallbladder cancer is not a standardized treatment, it may be a therapeutic option in cases of limited metastasis.