Impact of Whole Genome Doubling on Detection of Circulating Tumor DNA in Colorectal Cancer.

OBJECTIVE: Circulating tumor DNA (ctDNA) is a candidate biomarker of cancer with practice-changing potential in the detection of both early and residual disease. Disease stage and tumor size affect the probability of ctDNA detection, whereas little is known about the influence of other tumor characteristics on ctDNA detection. This study investigates the impact of tumor cell whole-genome doubling (WGD) on the detection of ctDNA in plasma collected preoperatively from newly diagnosed colorectal cancer (CRC) patients. METHODS: WGD was estimated from copy numbers derived from whole-exome sequencing (WES) data of matched tumor and normal DNA from 833 Danish CRC patients. To explore if tumor WGD status impacts ctDNA detection, we applied tumor-informed ctDNA analysis to preoperative plasma samples from all patients. RESULTS: Patients with WGD+ tumors had 53% increased odds of being ctDNA positive (OR = 1.53, 95%CI: 1.12-2.09). After stratification for UICC stage, the association persisted for Stage I (OR = 2.44, 95%CI: 1.22-5.03) and Stage II (OR = 1.76, 95%CI: 1.11-2.81) but not for Stage III (OR = 0.83, 95%CI: 0.44-1.53) patients. CONCLUSION: The presence of WGD significantly increases the probability of detecting ctDNA, particularly for early-stage disease. In patients with more advanced disease, the benefit of WGD on ctDNA detection is less pronounced, consistent with increased DNA shedding from these tumors, making ctDNA detection less dependent on the amount of ctDNA released per tumor cell.

[Transanal endoscopic microsurgery for excision of a symptomatic tailgut cyst].

A tailgut cyst is a rare tumour originating from the embryonic remnant of the retrorectal space. The cyst is often asymptomatic, but it can cause abdominal or rectal pain and urogenital symptoms. When diagnosed, resection is the choice of treatment, and traditionally open surgery has been preferred. In this case report, we present a 30-year-old female patient with a painful tailgut cyst. She was found to be candidate for transanal endoscopic microsurgery, which was successfully performed.

Prevention of anastomotic leak following surgical treatment for rectal cancer.

INTRODUCTION: Anastomotic leak (AL) is a major complication to surgical treatment of colorectal cancer affecting approximately 12% of patients. AL is associated with a 6-30% mortality. Finding methods that may reduce the incidence of AL is therefore important. In this study, we aimed to examine the effect of mechanical bowel preparation (MBP) and oral antibiotics on the rate of AL. METHODS: This was a retrospective, single-centre analysis of patients undergoing surgical treatment for rectal cancer. We included 150 consecutive patients treated from July 2014 to October 2018. From June 2017 onwards, 50 patients comprised the study group (receiving MBP and oral antibiotics), while the preceding 100 patients served as a control group (receiving a rectal enema). RESULTS: Two cases (4%) of AL were found in the study group and 20 cases (20%) in the control group (p lesser-than 0.01). Converting from laparoscopy to open surgery or having a World Health Organization performance score 2-3 were also associated with AL in univariate analysis. CONCLUSION: Administrating MBP and oral antibiotics prior to surgery seems to reduce the incidence of AL following rectal cancer surgery. FUNDING: none. TRIAL REGISTRATION: not relevant.

The effect of a diverting stoma on morbidity and risk of permanent stoma following anastomotic leakage after low anterior resection for rectal cancer: a nationwide cohort study.

BACKGROUND: Diverting stomata (DS) have been shown to mitigate the clinical impact of anastomotic leakage (AL) but not without complications, and their routine use remains a matter of international debate. The objective of this study was to examine the association between stomata and the clinical consequences of AL. METHODS: This was a nationwide retrospective cohort study including all patients suffering from AL after low anterior resection from 2001 to 2010. RESULTS: Four thousand sixty-three patients were treated in the period of whom 581 (11.9%) developed AL. In case of AL, patients without a diverting stoma had a slightly higher 90-day mortality rate (13.5% versus 8.7%, p = 0.089). Patients suffered more complications due to AL, both surgical (52% versus 28%, p < 0.001) and non-surgical (48% versus 35%, p = 0.004) with a higher Clavien-Dindo score. Twenty percent of patients developed stoma-related complications prior to stoma reversal. Mortality related to stoma reversal was 2.4%. Factors associated with a risk of a permanent stoma were age (HR 1.04, 95% CI 1.01-1.08), blood transfusion during primary surgery (HR 2.35, 95% CI 1.16-4-78), conserved anastomosis after AL (HR 0.019, 95% CI 0.009-0.04), and a diverting stoma fashioned at the index operation (HR 0.50, 95% CI 0.26-0.97). CONCLUSION: The use of diverting stomata during low anterior resection mitigates the clinical impact of AL. However, this benefit needs to be balanced against the risk of stoma-related complications, seen in 20%, and mortality with stoma reversal (2.4%). Where practical, the decision to divert should be made pre-operatively in a multidisciplinary setting.

Percutaneous yttrium aluminum garnet-laser lithotripsy of intrahepatic stones and casts after liver transplantation.

Bile duct stones and casts (BDSs) contribute importantly to morbidity after liver transplantation (LT). The purpose of this study was to estimate the clinical efficacy, safety, and long-term results of percutaneous transhepatic cholangioscopic lithotripsy (PTCSL) in transplant recipients and to discuss underlying factors affecting the outcome. A retrospective chart review revealed 18 recipients with BDSs treated by PTCSL laser lithotripsy with a holmium-yttrium aluminum garnet laser probe at 365 to 550 µm. They were analyzed in a median follow-up time of 55 months. In all but 1 patient (17/18 or 94%), it was technically feasible to clear all BDSs with a mean of 1.3 sessions. PTCSL was unsuccessful in 1 patient because of multiple stones impacting the bile ducts bilaterally; 17% had early complications (Clavien II). All biliary casts were successfully cleared; 39% had total remission; 61% needed additional interventions in the form of percutaneous transhepatic cholangiography and dilation (17%), re-PTCSL (11%), self-expandable metallic stents (22%), or hepaticojejunostomy (6%); and 22% eventually underwent retransplantation. The overall liver graft survival rate was 78%. Two patients died during follow-up for reasons not related to their BDS. Nonanastomotic strictures (NASs) were significantly associated with treatment failure. We conclude that PTCSL in LT patients is safe and feasible. NASs significantly increased the risk of relapse. Repeated minimally invasive treatments, however, prevented graft failure in 78% of the cases.

[Dealing with surgical complications after bariatric gastric bypass surgery]. / Håndtering af kirurgiske komplikationer efter gastrisk bypassoperation for fedme

The subject of this article is surgical complications to Roux-en-Y-gastric bypass and how to deal with them. The article addresses doctors, who are on duty in hospitals without bariatric surgery and who often deal with this patient category in the acute situation. Managing complications is challenging due to both the patient's physiognomy and the wide-ranged change in anatomy. The article gives a review of the literature and hands-on-recommendations for treating anastomotic leak, post-operative bleeding, internal herniation, bowel obstruction and biliary complications.

Significance of acquired diverticular disease of the vermiform appendix: a marker of regional neoplasms?

AIM: To assess the prevalence of acquired diverticulum of the appendix (DA), including incipient forms and its possible significance as a marker of local/regional neoplasms. MATERIALS AND METHODS: The pathology database at Hvidovre Hospital was searched for appendix specimens, received between 2001 and 2010, coded for DA or for a space-occupying lesion. Slides were reviewed to determine DA status and the nature of lesions possibly causing DA. RESULT: Among 4413 appendix specimens, DA were identified in 39 (0.9%, CI 0.6% to 1.2%) cases, 17 (43.6%, 28.0% to 59.2%) of which additionally harboured an appendiceal neoplasm/neoplastic precursor, whereas this figure was 1.2% (CI 0.9% to 1.6%) for non-DA specimens (p<0.0001). Six of the 39 DA specimens comprised incipient DA, three of which coexisted with appendiceal neoplasms. In addition, local/regional non-neoplastic lesions (six cases) and colorectal carcinomas (four cases) coexisted with DA. CONCLUSION: DA has significance as a putative marker of local/regional neoplasms. Therefore, a DA specimen proved significantly more likely to harbour a neoplastic growth than a non-DA counterpart. Submission for microscopy of the entire DA specimen, whether transmural or only incipient, and a comment in the pathology report on the occasional concurrence of local/regional neoplasms in this setting seem appropriate. The observation of DA may thus provide a valuable contribution in the diagnostic process.

[Necrotizing fasciitis after arthroscopic synovectomy of an infected prepatellar bursa]. / Fasciitis necroticans efter artroskopi af praepatellar bursitis.

Necrotizing fasciitis (NF) is a life-threatening soft tissue infection in superficial and deep fascias. NF is most often caused by mixed aerobic and anaerobic bacteria. The treatment is early and aggressive surgical debridement, antibiotics and hyperbaric oxygen. In this case description, a nearly 60-year-old man developed NF after arthroscopic synovectomy of an infected prepatellar bursa. We stress the point that the endoscopic technique itself might be responsible for the spreading of bacteria to the fascias. This is a subject for further investigation.