Precise highlighting of the pancreas by semantic segmentation during robot-assisted gastrectomy: visual assistance with artificial intelligence for surgeons.

BACKGROUND: A postoperative pancreatic fistula (POPF) is a critical complication of radical gastrectomy for gastric cancer, mainly because surgeons occasionally misrecognize the pancreas and fat during lymphadenectomy. Therefore, this study aimed to develop an artificial intelligence (AI) system capable of identifying and highlighting the pancreas during robot-assisted gastrectomy. METHODS: A pancreas recognition algorithm was developed using HRNet, with 926 training images and 232 validation images extracted from 62 scenes of robot-assisted gastrectomy videos. During quantitative evaluation, the precision, recall, intersection over union (IoU), and Dice coefficients were calculated based on the surgeons' ground truth and the AI-inferred image from 80 test images. During the qualitative evaluation, 10 surgeons answered two questions related to sensitivity and similarity for assessing clinical usefulness. RESULTS: The precision, recall, IoU, and Dice coefficients were 0.70, 0.59, 0.46, and 0.61, respectively. Regarding sensitivity, the average score for pancreas recognition by AI was 4.18 out of 5 points (1 = lowest recognition [less than 50%]; 5 = highest recognition [more than 90%]). Regarding similarity, only 54% of the AI-inferred images were correctly differentiated from the ground truth. CONCLUSIONS: Our surgical AI system precisely highlighted the pancreas during robot-assisted gastrectomy at a level that was convincing to surgeons. This technology may prevent misrecognition of the pancreas by surgeons, thus leading to fewer POPFs.

Treatment strategy for successful conversion surgery in clinical stage IVB gastric cancer.

INTRODUCTION: Recent advances in chemotherapy have resulted in successful conversion surgery (CS) for clinical stage (cStage) IVB gastric cancer (GC). This study aimed to evaluate the success rate of CS in clinical practice and determine optimal treatment strategies. METHODS: Totally, 166 patients with cStage IVB gastric and gastroesophageal junction adenocarcinoma, who underwent chemotherapy at Hyogo Medical University Hospital between January 2017 and June 2022, were included. CS was performed after confirming tumor to be M0 based on imaging and/or staging laparoscopy, except for resectable liver metastases. Preoperative chemotherapy was continued for at least 6 months provided that adverse events were manageable. RESULTS: Of 125 eligible patients, 23 were treated with CS, achieving a conversion rate of 18.4% and an R0 resection rate of 91.3%. The median duration of preoperative chemotherapy was 8.5 months; the median number of cycles was eight. The highest conversion rate was observed in patients receiving first-line treatment (14.4%), followed by those receiving second and third lines (5.8% and 2.3%, respectively). The median survival time in patients who received CS was significantly longer than that in patients who continued chemotherapy alone (56.7 versus 16 months, respectively, P < 0.0001). There was no significant difference in the 3-year overall survival between the patients who achieved CS after first-line treatment (63.2%, n = 18) and those who achieved CS after second- or third-line treatment (66.7%, n = 5). CONCLUSION: Consistent chemotherapy strategies could lead to successful CS and improved prognosis in a greater number of patients with cStage IVB GC, regardless of line of treatment.

Proposal for T3 classification of esophagogastric junction carcinoma based on the interconnection of extramural anatomical structures.

Classification of extramural invasion of esophagogastric junction carcinoma (EGJC) is not yet established. The anatomy surrounding the EGJ alters between the mediastinum and the abdominal cavity. This review proposed a T3 classification of EGJC based on anatomical continuity. Analysis of endoscopic ultrasound images, review of intraoperative images, and detailed observation of surgical specimens were followed by a review of the literature. In the EGJ, the muscularis propria of the esophagus is enclosed in mediastinal adipose tissue called the adventitia, which is surrounded by the diaphragmatic crus and contains the paraesophageal lymph nodes (LNs). After passing through the esophageal hiatus along with the vagus nerves and blood vessels, the adventitia joins the adipose tissue containing the paracardial LNs, which is covered by the peritoneum, and then further divides into the lesser and greater omentum. The connective tissue outside the muscularis propria of the stomach, including the adipose tissue of the omentum, is called the subserosa. According to the TNM classification, T3 esophageal and gastric cancer is defined as invasion of the adventitia and subserosa, respectively. Given that the adventitia is anatomically continuous with the subserosa, T3 tumors of the EGJ can be described as those that extend through the muscularis propria but do not invade the peritoneum or diaphragmatic crus. We propose classifying T3 EGJC as "tumor extends through muscularis propria" rather than using the separate terms "adventitia" and "submucosa". T4 could be "tumor perforates serosa or invades adjacent structures", as per the current gastric cancer classification.

[A Case of Breast Cancer in the Elderly Localized in the Nipple].

An 89-year-old woman presented to our clinic with a complaint of a wound in the left nipple. The pathological diagnosis via skin biopsy revealed adenocarcinoma. A physical examination, mammography, ultrasonography, and CT scan revealed a mass in the left nipple. However, a definite diagnosis could not be established by skin biopsy. Left breast-conserving surgery and sentinel lymph node biopsy were performed for diagnosis and treatment. Histological examination revealed a scirrhous type invasive ductal carcinoma in the left nipple and areola with skin invasion and lymph node metastasis. Radiation and hormone therapy were used as adjuvant therapy. She is alive with no local recurrence for 5 months post surgery. Since ductal carcinoma of the nipple is uncommon, we present this case report along with a review of the relevant literature.

Laparoscopic gastrectomy with and without prophylactic drains in gastric cancer: a propensity score-matched analysis.

BACKGROUND: The number of patients who are undergoing laparoscopic gastrectomy for treating gastric cancer is increasing. Although prophylactic drains have been widely employed following the procedure, there are few studies reporting the efficacy of prophylactic drainage. Therefore, this study assessed the efficacy of prophylactic drains following laparoscopic gastrectomy for gastric cancer. METHODS: Data of patients who received laparoscopic gastrectomy for treating gastric cancer in our institution between April 2011 and March 2017 were reviewed, and the outcomes of patients with and without a prophylactic drainage were compared. Propensity score matching was used to minimize potential selection bias. RESULTS: A total of 779 patients who underwent surgery for gastric cancer were reviewed; of these, 628 patients who received elective laparoscopic gastrectomy were included in this study. After propensity score matching, data of 145 pairs of patients were extracted. No significant differences were noted in the incidence of postoperative complications between the drain and no-drain groups (19.3% vs 11.0%, P = 0.071). The days after the surgery until the initiation of soft diet (6.3 ± 7.4 vs 4.9 ± 2.9 days, P = 0.036) and the length of postoperative hospital stay (15.7 ± 12.9 vs 13.0 ± 6.3 days, P = 0.023) were greater in the drain group than those in the no-drain group. CONCLUSIONS: This study suggests that routinely using prophylactic drainage following laparoscopic gastrectomy for treating gastric cancer is not obligatory.

[A Case of Stage IV Gastric Cancer Which Showed Pathological Complete Response after Neo-Adjuvant Chemotherapy].

We report a case of Stage IV gastric cancer showing pathological complete response(pCR)after neo-adjuvant chemotherapy( NAC)using S-1 and oxaliplatin(SOX).A woman 73-year-old was diagnosed as harming type 3 Stage IV gastric cancer with para-aortic lymph node(PAN)metastasis.She underwent 4 courses of NAC with SOX regimen.After the treatment, both the primary tumor and the metastatic PAN decreased in size remarkably.She underwent distal gastrectomy with D2 plus PAN dissection with curative intent.Pathological diagnosis revealed complete disappearance of cancer cells in both the primary lesion of the stomach and all dissected lymph nodes, confirming pCR.She is alive without recurrence 4 months after surgery.

[A Case of Small Intestinal Cancer Repeating an Ileus Symptom Complicated with Refractory Arrhythmia].

A 56-year-old man had been treated for hypertrophic cardiomyopathy since childhood. He had been treated for refractory ventricular tachycardia (VT) with interventricular septum cauterization, catheter ablation, and implantation of a defibrillator. He had been treated at home for several years. The ileus that developed in July 2014 was relieved by conservative medical treatment once, but it recurred after oral intake of food a short time later. The obstruction was due to a small intestine cancer that was diagnosed by enteroscopy. After considering the risks of surgery due to the cardiac problem and the quality of life due to ileus caused by the mass, we resected it. This surgery was not a radical resection because of peritoneal dissemination. He started oral food intake postoperatively, and returned to home care. Three months after surgery, oral chemotherapy was administered after considering his stable cardiac function in addition to his coherent mental status. An adverse event of severe watery diarrhea developed, and VT caused by dehydration occurred. After the chemotherapy was discontinued, he recovered in intensive care. He returned to home care at his prior status for 9 months postoperatively.

[A Case of Carcinosarcoma of the Esophagus Treated with Chemoradiotherapy].

Carcinosarcoma of the esophagus is a rare malignant neoplasm. We report a case of an 87-year-old man treated with chemoradiotherapy. The main presenting complaint was hiccups. Histological analysis of a biopsy from the tumor demonstrated a carcinosarcoma. The clinical diagnosis was T2N0M0, cStageⅡ. In consideration of his advanced age, a past history of cerebral infarction, high blood pressure, aortic valve sclerosis, and chronic renal failure (Cr 1.5-1.8 mg/dL), chemoradiotherapy consisting of TS-1 40 mg/day with radiotherapy of 66 Gy was administered to the patient. The carcinosarcoma decreased in size on endoscopic examination in response to the chemoradiotherapy. Surgery with extended lymphadenectomy for esophageal carcinosarcoma is the standard treatment, but chemotherapy may be a good choice for local control for patients who cannot undergo surgical resection.

[A case of resection of pancreatic head lymph node metastasis of rectal carcinoid].

An 80-year-old woman was treated with low anterior resection and D3 lymph node dissection for rectal carcinoid in August 2007. Pathological diagnosis was a tumor 23 × 22 mm in size with muscularis propria invasion, ly1, v0, n1 (No. 251[1/12]). Partial hepatectomy was performed for liver metastasis in March 2010 and September 2011. In June 2013, an isolated tumor of 17 mm in diameter was detected between the inferior vena cava and the stomach using abdominal ultrasonography. The tumor was diagnosed as pancreatic head lymph node metastasis using abdominal enhanced computed tomography (CT), magnetic resonance cholangiopancreatography (MRCP), and positron emission tomography (PET); fluorodeoxyglucose (FDG) uptake was noted at the site of the tumor, but not at other parts of the body. Curative resection was the chosen treatment option. Open surgery was performed in September 2013, and a tumor 30 mm in diameter located at the ventral side of the inferior vena cava, lateral side of the portal vein, and cranial side of duodenum was resected. No surrounding tissue infiltration was found. Pathological analysis of the resected specimen indicated lymph node metastasis of the rectal carcinoid. The patient has been disease free for 9 months after surgery.