Absence of residual tumor tissue after Gamma Knife radiosurgery followed by resection of a vestibular schwannoma: illustrative case

BACKGROUND Late pathology after vestibular schwannoma radiosurgery is uncommon. The authors presented a case of a resected hemorrhagic mass 13 years after radiosurgery, when no residual tumor was found. OBSERVATIONS A 56-year-old man with multiple comorbidities, including myelodysplastic syndrome cirrhosis, received Gamma Knife surgery for a left vestibular schwannoma. After 11 years of stable imaging assessments, the lesion showed gradual growth until a syncopal event occurred 2 years later, accompanied by progressive facial weakness and evidence of intralesional hemorrhage, which led to resection. However, histopathological analysis of the resected specimen showed hemorrhage and reactive tissue but no definitive residual tumor. LESSONS This case demonstrated histopathological evidence for the role of radiosurgery in complete elimination of tumor tissue. Radiosurgery for vestibular schwannoma carries a rare risk for intralesional hemorrhage in select patients.

Smooth muscle degeneration of the mesenteric and branching veins causing ischemic enteritis: a case report

Background Ischemic bowel injuries are generally caused by arteriosclerosis, thromboembolism, or vasculitis. Ischemic enteritis is less common than ischemic colitis because of the rich collateral arteries of the small intestine. In the present case, smooth muscle degeneration of the mesenteric to the submucosal veins caused ischemic enteritis and small bowel obstruction. Case presentation An 85-year-old woman with recurrent enteritis eventually developed small bowel obstruction. We performed laparoscopic partial resection of the small intestine. The pathological findings revealed smooth muscle degeneration of the mesenteric veins that caused ischemic enteritis. Venous changes were detected not only in the injured region, but also in a part of the normal region of the resected specimen. She continued to experience some minor symptoms postoperatively; however, these symptoms subsided in a short period with medicine discontinuation. Conclusion This report shows the possibility that a disease causes ischemic enteritis with unique venous pathological changes and may recur postoperatively.

Completion surgery vs. primary TME for early rectal cancer: a national study

Purpose While local excision by transanal endoscopic microsurgery (TEM) or transanal minimally invasive surgery (TAMIS) is an option for low-risk early rectal cancers, inaccuracies in preoperative staging may be revealed only upon histopathological evaluation of the resected specimen, demanding completion surgery (CS) by formal resection. The aim of this study was to evaluate the results of CS in a national cohort. Method This was a retrospective analysis of national registry data, identifying and comparing all Norwegian patients who, without prior radiochemotherapy, underwent local excision by TEM or TAMIS and subsequent CS, or a primary total mesorectal excision (pTME), for early rectal cancer during 2000–2017. Primary endpoints were 5-year overall and disease-free survival, 5-year local and distant recurrence, and the rate of R0 resection at completion surgery. The secondary endpoint was the rate of permanent stoma. Results Forty-nine patients received CS, and 1098 underwent pTME. There was no difference in overall survival (OR 0.73, 95% CI 0.27–2.01), disease-free survival (OR 0.72, 95% CI 0.32–1.63), local recurrence (OR 1.08, 95% CI 0.14–8.27) or distant recurrence (OR 0.67, 95% CI 0.21–2.18). In the CS group, 53% had a permanent stoma vs. 32% in the pTME group (P = 0.002); however, the difference was not significant when adjusted for age, sex, and tumor level (OR 2.17, 0.95–5.02). Conclusions Oncological results were similar in the two groups. However, there may be an increased risk for a permanent stoma in the CS group.

Alpha Smooth Muscle Actin (αSMA) Immunohistochemistry Use in the Differentiation of Pancreatic Cancer from Chronic Pancreatitis

Aim: Fibrosis is observed both in pancreatic cancer (PDAC) and chronic pancreatitis (CP). The main cells involved in fibrosis are pancreatic stellate cells (PSCs), which activate alpha smooth muscle actin (αSMA), which is considered to be the best-known fibrosis marker. The aim of the study was to evaluate the expression of the αSMA in patients with PDAC and CP as the possible differentiation marker. Methods: We enrolled 114 patients undergoing pancreatic resection: 83 with PDAC and 31 with CP. Normal fragments of resected specimen from 21 patients represented the control tissue. The immunoexpressions of αSMA were detected in tissue specimens with immunohistochemistry (Abcam antibodies, GB). Results: Mean cytoplasmatic expression of αSMA protein in PDAC stromal cells was significantly higher compared to CP: 2.42 ± 0.37 vs 1.95 ± 0.45 (p < 0.01) and control group 0.61 ± 0.45 (p < 0.01). Strong immunoexpression of the αSMA protein was found in the vast majority (80.7%) of patients with PDAC, in about half (58%) of patients with CP, and not at all in healthy tissue. The expression of αSMA of different intensity was found in all patients with PDAC and CP, while in healthy tissue was minimal or absent. In PDAC patients, αSMA expression was significantly higher in tumors of diameter higher than 3 cm compared to smaller ones (p = 0.017). Conclusions: Presented findings confirm the significant role of fibrosis in both PDAC and CP; however, they do not confirm the role of αSMA as a marker of differentiation.

Primary retroperitoneal liposarcoma: a rare case report

Primary retroperitoneal liposarcoma (PRPLS) is a rare malignant tumor with a low incidence. A 34-year-old female patient presented to our department with abdominal pain, nausea, and vomiting for 2 days. Abdominal computed tomography (CT) indicated a huge mass between the liver and kidney, with a clear boundary and measuring approximately 202 mm × 155 mm ×106 mm. The mass was considered a retroperitoneal lipoma or liposarcoma. The entire tumor was completely resected without auxiliary injury, and histopathology of the resected specimen indicated liposarcoma. The patient recovered well and was discharged from our department on the 6th postoperative day. No signs of relapse were seen during 1-year of follow-up. PRPLS is rare and without obvious symptoms in the early stage. CT plays a vital role in the diagnosis of PRPLS, and surgical resection is considered the most suitable treatment. Radiotherapy and chemotherapy might also be treatment options to improve the overall survival of PRPLS patients.

P-OGC86 Textbook Outcome following Oesophagectomy for Oesophageal Cancer: An International Cohort Study

Background Although textbook outcome (TO) has been proposed as a tool for the assessment of oncological surgical care, an international assessment in patients undergoing oesophagectomy for oesophageal cancer has not been reported. This study aimed to assess TO in an international setting. Methods Patients undergoing curative resection for oesophageal cancer were identified from the international Oesophagogastric Anastomosis Audit (OGAA) from April 2018 - December 2018. TO was defined as the percentage of patients who underwent a complete tumour resection with at least 15 lymph nodes in the resected specimen and an uneventful postoperative course, without hospital readmission. A multivariable binary logistic regression model was used to identify factors independently associated with TO, and results are presented as odds ratio (OR) and 95% confidence intervals (CI95%). Results This study included 2,159 patients with oesophageal cancer, of whom 39.7% achieved a TO. The outcome parameter ‘no major postoperative complication’ had the greatest negative impact on a TO for patients with oesophageal cancer, compared to other TO parameters. Multivariable analysis identified male gender, increasing Charlson comorbidity index, and higher AJCC T and N staging to be associated with a significantly lower likelihood of TO. After accounting for these factors, high volume centres (&gt;50 cases/year; OR: 1.36, CI95%: 1.06 - 1.75, p = 0.015), presence of 24-hour on-call rota for oesophageal surgeons (OR: 2.11, CI95%: 1.33 - 3.35, p = 0.001) and radiology (OR: 1.56, CI95%: 1.08 - 2.26, p = 0.019), total minimally invasive esophagectomies (OR: 1.60, CI95%: 1.25 - 2.05, p &lt; 0.001), and chest anastomosis above azygous (OR: 2.17, CI95%: 1.58 - 2.98, p &lt; 0.001) were independently associated with a significantly increased likelihood of TO. Conclusions TO is achieved in less than 40% of patients having oesophagectomy for cancer. Improvements in centralisation, hospital resources (i.e. daily 24-hour on-call esophagogastric surgeons and radiologists), access to minimal access surgery, and adoption of newer techniques for improving lymph node yield could improve TO. Understanding how these individual parameters help improve quality of patient care should be the focus of future research.

Duodenal stenosis associated with an ectopic opening of the common bile duct into the duodenal bulb: a case report

Background Ectopic opening of the common bile duct is a rare congenital biliary anomaly. Herein, we present a case of duodenal stenosis with ectopic opening of the common bile duct into the duodenal bulb. Case presentation A 54-year-old man was referred with fever, nausea, and vomiting. He had experienced epigastric pain several times over the past 30 years. Endoscopy showed a post-bulbar ulcer, a submucosal tumor of the duodenum, and a small opening with bile secretion. Contrast duodenography revealed duodenal stenosis and bile reflux with a common bile duct deformity. Pancreatoduodenectomy was performed because of the clinical suspicion of a biliary neoplasm or groove pancreatitis. The resected specimen showed an ectopic opening of the common bile duct into the duodenal bulb and no tumor. Conclusions Ectopic opening of the common bile duct into the duodenal bulb is complicated by a duodenal ulcer, deformity, and stenosis mimicking groove pancreatitis or pancreatic tumors. Although rare, we should be aware of this anomaly for an accurate diagnosis.

P-L15 Fluorescence guided laparoscopic resection of Colorectal Liver Metastases: Same day administration of indocyanine green with use of SPY- Colour Segmented Fluorescence imaging to identify tumours intra-operatively

Background Near-infrared fluorescent (NIRF) imaging using indocyanine green (ICG) has various applications in minimally invasive surgery. There are a number of techniques in timing and dose administration. Visually different fluorescent enhancement patterns correlate with different pathologies to aid identification of lesions intra-operatively. The aim of this study is to present our experience with utilisation of Colour Segmented Fluorescence ICG mode in laparoscopic liver surgery for colorectal liver metastases. Methods We present a single surgeon (SA) experience with the use of laparoscopic fluorescence guided imaging surgery (L-FGIS). Between November 2020 and July 20201, L-FGIS was used in seven patients with suspected CRLM. ICG was administered intravenously at a dose of 0.2 to 0.3 mg/kg IV 2-3 hours prior to liver surgery. Through use of the SPY Colour Segmented Fluorescence (CSF) imaging mode, the image is scaled as to NIRF fluorescence intensity to allow for the clear identification of the CRLM intra-operatively. Results A total of seven patients (Four males) with median age of 74.3 years (range: 30.5 -86) underwent L-FGIS during the study period. Two out of seven patients underwent re-do liver surgery. The median size of the tumour was 27mm (range: 10-65mm) and median number of tumours were one (range: 1-2). To visualise the tumour and to avoid interference of green background liver, ICG camera was switched to CSF mode. All lesions had signet ring appearance under CSF mode (see figure 1). Except in one patient (necrotic lesion), the histology of resected specimen contained a well to moderately differentiated colorectal adenocarcinoma metastasis. R0 resection was achieved in all patients and median clearance of the tumour was 3mm (range 0.4-10mm). Conclusions In our limited experience ICG administered at least 2-3 hours prior to surgery can identify superficially located colorectal metastases, provided ICG camera is switched to CSF mode. Superficially located lesions are easily identifiable under CSF mode. CSF mode helped us to identify the lesions and to mark the resection margin. The use of ICG is an important advancement in CRLM surgery and further research is needed to optimise image interpretation and correlate with clinical resection outcomes.