Three-dimensional simulation of the pancreatic parenchyma, pancreatic duct and vascular arrangement in pancreatic surgery using a deep learning algorithm.

Three-dimensional surgical simulation, already in use for hepatic surgery, can be used in pancreatic surgery. However, some problems still need to be overcome to achieve more precise pancreatic surgical simulation. The present study evaluates the performance of SYNAPSE VINCENT® (version 6.6, Fujifilm Medical Co., Ltd., Tokyo, Japan) in the semiautomated surgical simulation of the pancreatic parenchyma, pancreatic ducts, and peripancreatic vessels using an artificial intelligence (AI) engine designed with deep learning algorithms. One-hundred pancreatic cancer patients and a control group of 100 nonpancreatic cancer patients were enrolled. The evaluation methods for visualizing the extraction were compared using the Dice coefficient (DC). In the pancreatic cancer patients, tumor size, position, and stagewise correlations with the pancreatic parenchymal DC were analyzed. The relationship between the pancreatic duct diameter and the DC, and between the manually and AI-measured diameters of the pancreatic duct were analyzed. In the pancreatic cancer/control groups, the pancreatic parenchymal DC and pancreatic duct extraction were 0.83/0.86 and 0.84/0.77. The DC of the arteries (portal veins/veins) and associated sensitivity and specificity were 0.89/0.88 (0.89/0.88), 0.85/0.83 (0.85/0.82), and 0.82/0.81 (0.84/0.81), respectively. No correlations were observed between pancreatic parenchymal DC and tumor size, position, or stage. No correlation was observed between the pancreatic duct diameter and the DC. A positive correlation (r = 0.61, p<0.001) was observed between the manually and AI-measured diameters of the pancreatic duct. Extraction of the pancreatic parenchyma, pancreatic duct, and surrounding vessels with the SYNAPSE VINCENT® AI engine assumed to be useful as surgical simulation.

Recent trends in the prevalence and distribution of colonic diverticula in Japan evaluated using computed tomography colonography.

BACKGROUND: Computed tomography colonography (CTC) may be superior to colonoscopy and barium enema for detecting diverticula. However, few studies have used CTC to diagnose diverticula. AIM: To evaluate the current prevalence and distribution of colonic diverticula in Japan using CTC. METHODS: This study was conducted as part of the Japanese National Computed Tomographic Colonography Trial, which included 1181 participants from 14 hospitals in Japan. We analyzed the prevalence and distribution of colonic diverticula and their relationships with age and sex. The relationship between the diverticula and the length of the large intestine was also analyzed. RESULTS: Diverticulosis was present in 48.1% of the participants. The prevalence of diverticulosis was higher in the older participants (P < 0.001 for trend). The diverticula seen in younger participants were predominantly located in the right-sided colon. Older participants had a higher frequency of bilateral type (located in the right- and left-sided colon) diverticulosis (P < 0.001 for trend). The length of the large intestine with multiple diverticula in the sigmoid colon was significantly shorter in those without diverticula (P < 0.001). CONCLUSION: The prevalence of colonic diverticulosis in Japan is higher than that previously reported. The prevalence was higher, and the distribution tended to be bilateral in older participants.

Possibility of determining the degree of adhesion of the lymph node to the pulmonary artery preoperatively.

BACKGROUND: To make a preoperative determination of the degree of adhesion of the lymph node (LN) to the pulmonary artery (PA) in patients with lung cancer. METHODS: We investigated clinical parameters, including sex, age, smoking, stage, histology and surgical procedure, and performed an image analysis using CT scanning. RESULTS: The data for sex, age, smoking, stage, histology and the surgical procedure were identical between the "adhesion" and "no adhesion" groups. However, three of the five analyzable cases in the adhesion group clearly showed the disappearance of the fat plane on minimum intensity projection (minIP) computed tomography (CT). In particular, sites on more than three slices demonstrated the disappearance of the fat plane. On the other hand, five of the eight analyzable cases in the no adhesion group showed no disappearance of the fat plane. Therefore, one central slice adequately reflected the fat plane in the cases in the no adhesion group. CONCLUSIONS: These findings suggest that it is necessary to obtain a careful diagnosis of the extent of attachment of the LN to the PA using modern diagnostic imaging in order to preoperatively assess the degree of adhesion of the LN to adjacent structures.

Analysis of complete response by MRI following neoadjuvant chemotherapy predicts pathological tumor responses differently for molecular subtypes of breast cancer.

In the present study, clinical tumor response following neoadjuvant chemotherapy (NAC) was diagnosed by magnetic resonance imaging (MRI) and clinicopathological factors, including molecular subtypes at baseline, were analyzed for correlations with pathological tumor responses. In addition, clinicopathological factors were analyzed for a correlation with the MRI capacity to predict pathological complete response (pCR). Clinical tumor response evaluated by MRI following NAC was determined as a clinical CR (cCR) or a residual tumor. cCR was confirmed if no gadolinium enhancement or an enhancement equal to or less than that of glandular tissue was observed in any phase of the MRI. Pathological tumor responses following NAC were classified into grades 0 (no change) to 3 (no residual invasive cancer) according to criteria of the Japanese Breast Cancer Society. pCR was defined as grade 3 in the present study. Of 264 cases of invasive breast cancer in 260 patients (4 synchronous bilateral breast cancer cases), 59 (22%) were diagnosed by MRI following NAC as cCR and 98 (37%) were pathologically diagnosed as pCR. In terms of predicting pCR by MRI, the sensitivity, specificity, accuracy, positive predictive value (PPV) and negative predictive value (NPV) were 44, 90, 73, 73 and 73%, respectively. Tumor size, hormone receptor status, human epidermal growth factor receptor 2 (HER2) status, molecular subtype and histological type were significantly correlated with pathological tumor responses. pCR rates increased in the following order: luminal/HER2-negative (14%), luminal/HER2-positive (32%), triple-negative (46%) and non-luminal/HER2-positive (73%) tumors. Sensitivity and specificity were the highest (60 and 100%, respectively) in triple-negative tumors. PPV decreased in the following order: triple-negative (100%), non-luminal/HER2-positive (92%), luminal/HER2-positive (46%) and luminal/HER2-negative (33%) tumors. In conclusion, MRI evaluation is useful for predicting pCR following NAC, particularly for triple-negative tumors.

[Intramucosal colorectal carcinomas treated by surgical resection].

Stage 0 colorectal cancer was found only in the innermost lining of the colon and rectum. Treatments for an early stage colorectal cancer were available including endoscopic polypectomy, endoscopic mucosal resection (EMR) and trans-anal or -sacral local excision, laparoscopy-assisted colectomy and open colectomy. Our study indicated that endoscopic therapy for the early stage colorectal cancer was more advantageous than the conventional operative treatment. Although EMR should be applied for intramucosal carcinomas, 11 intramucosal carcinomas were treated by a surgical resection due to several limitations at our institution.

[Bladder preservation by chemoradiotherapy in combination with radical TUR-Bt in muscle invasive bladder cancer].

PURPOSE: To evaluate bladder preservation protocol by radical TUR-Bt and subsequent concurrent chemoradiotherapy in muscle invasive bladder cancer. PATIENTS AND METHODS: Twenty-six patients with muscle invasive bladder cancer (T2-T4NOM0) were treated with concurrent chemoradiotherapy after transurethral resection of the tumor as much as possible beyond muscle layers. Chemotherapy was consisted of systemic administration of methoterexete (30 mg/m2 day 1 and day 22) and intraarterial infusion of cisplatin (70 mg/m2, day 2 and day 23). The response was evaluated by TUR, urine cytology, CT and/or MRI 4 to 6 weeks after the treatment. RESULTS: Among 24 evaluable cases, pathological complete response was achieved in 13 cases (50%) and residual tumors were noted in 11 cases (pT1 in 9 and pT2 in 2). During follow-up period up to 69.8 months, invasive recurrence was observed in 2 cases, superficial recurrence was noted in 5 patients and distant metastasis without evidence of local recurrence was noted in 4 cases. Overall bladder preservation rate was 92%. CONCLUSIONS: The bladder preservation by radical TUR-Bt and chemoradiotherapy is a safe and effective treatment option for muscle invasive bladder cancer.

[A comparative study of CT and barium enema examination in diagnosis of peritoneal metastasis from gastric carcinoma].

OBJECTIVE: To compare the results of CT and barium enema examination in the diagnosis of peritoneal metastasis from gastric carcinoma. MATERIALS: Peritoneal metastases were pathologically confirmed in nine patients with gastric carcinoma who had had abdominal CT and barium enema examinations prior to surgery. METHODS AND RESULTS: Five patients were reported to have colonic wall rigidity on preoperative barium enema examination. Review of the images indicated that six cases showed rigidity. On the other hand, no CT findings suggestive of peritoneal metastasis were reported in eight patients without ascites. No patients were indicated to have intraperitoneal nodules. For the retrospective evaluation, we changed the diagnostic procedure: the CT window setting was changed in wide window width (from 250 Hounsfield units (HU) to 400HU)and low window level (50-60HU to 0 HU), and reading mode was changed to a cine paging mode with a picture archiving and communication system (PACS) instead of hard-copy review. It followed that intraperitoneal nodules suggestive of peritoneal metastasis were detected in eight patients. CONCLUSION: On conventional image reading, barium enema examination is of greater assistance than CT examination for detecting peritoneal metastasis from gastric carcinoma. However, the new CT reading method with PACS is more sensitive than barium enema examination for diagnosing peritoneal metastasis.