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Background: Postoperative death measured 30 days after surgery is a conventional quality metric, whereas intervals up to 90 days are increasingly used, although data-driven time windows have scarcely been investigated.

Methods: The Swedish Colorectal Cancer Registry was used to identify all patients subjected resection for colorectal cancer between 2007 and 2020. All patients were followed up until 180 days after surgery. A join-point statistical hazard model was used to model a declining hazard to a transition point, followed by a stable death rate. This method was subsequently applied to describe postoperative deaths for the entire cohort and subgroups according to tumour location (colon and rectum).

Results: Some 56 096 patients electively operated on for colorectal cancer during the study interval were included, with a 30-day and 90-day fatality of 805 (1.43%) and 1458 (2.60%) patients respectively. The derived postoperative fatality window, after which the death rate transitioned to a stable rate, was 23.8 (95% c.i. 21.5 to 28.2) days after surgery. There was no significant difference in the time window between rectal cancer (22.9 days; 95% c.i. 15.1 to 28.4) and colon cancer (27.3 days; 95% c.i. 21.4 to 31.8) patients (P = 0.455). However, postoperative fatality time windows were extended in patients aged at least 80 years and with American Society of Anesthesiologists’ grade III or IV.

Conclusion: The traditional postoperative time window of 30 days was confirmed to be an appropriate metric in elective colorectal cancer surgery when evaluated with a hazards-based statistical framework. Importantly, this time window is influenced by older age and advanced co-morbidity, which could prompt increased vigilance for these patient groups.

BACKGROUND: Anastomotic leakage after anterior resection for rectal cancer is more common after total mesorectal excision compared to partial mesorectal excision but might be mitigated by a defunctioning stoma.

OBJECTIVE: The aim is to assess how anastomotic leakage is affected by type of mesorectal excision and defunctioning stoma use.

DESIGN: This is a retrospective multicenter cohort study evaluating anastomotic leakage after anterior resection. Multivariable Cox regression with HRs and 95% CIs was used to contrast mesorectal excision types and defunctioning stoma use with respect to anastomotic leakage, with adjustment for confounding.

SETTINGS: This multicenter study included patients from 11 Swedish hospitals between 2014 and 2018.

PATIENTS: Patients who underwent anterior resection for rectal cancer were included.

MAIN OUTCOMES MEASURES: Anastomotic leakage rates within and after 30 days of surgery are described up to 1 year after surgery.

RESULTS: Anastomotic leakage occurred in 24.2% and 9.0% of 1126 patients operated with total and partial mesorectal excision, respectively. Partial compared to total mesorectal excision was associated with a reduction in leakage, with an adjusted HR of 0.46 (95% CI, 0.29-0.74). Early leak rates within 30 days were 14.9% with and 12.5% without a stoma, whereas late leak rates after 30 days were 7.5% with and 1.9% without a stoma. After adjustment, defunctioning stoma was associated with a lower early leak rate (HR 0.47; 95% CI, 0.28-0.77). However, the late leak rate was nonsignificantly higher in patients with defunctioning stomas (HR 1.69; 95% CI, 0.59-4.85).

LIMITATIONS: This study was limited by its retrospective observational study design.

CONCLUSIONS: Anastomotic leakage is common up to 1 year after anterior resection for rectal cancer, where partial mesorectal excision is associated with a lower leak rate. Defunctioning stomas seem to decrease the occurrence of leakage, although partially by only delaying the diagnosis. See Video Abstract.

Background: Without evidence, positive expiratory pressure therapy is a part of rehabilitation worldwide to prevent postoperative hypoxia. Reading aloud could be used as an alternative therapy as lung volumes increases while speaking. We aimed to investigate whether reading aloud is superior to positive expiratory pressure therapy for improving oxygen saturation after abdominal surgery.

Material and Methods: This crossover randomized controlled trial compared reading a text aloud with positive expiratory pressure therapy in patients on postoperative day 1 or 2 after upper gastrointestinal, colorectal, urological, or gynecological abdominal surgery at Umeå University Hospital, Sweden. The primary outcome was the change in peripheral oxygen saturation compared with baseline at 7 min after the intervention. The secondary outcome was transcutaneous carbon dioxide partial pressure change.

Results: This study included 50 patients of which 48 patients were analyzed. Peripheral oxygen saturation rapidly decreased to minimum values below baseline immediately after both interventions and then increased to values above baseline after reading aloud (1%, 95% confidence interval 0.2% to 1%, P = 0.004), but not after positive expiratory pressure therapy (−0.2%, 95% confidence interval −1% to 0.4%, P = 0.436). The difference in oxygen saturation was 1% (95% confidence interval 0.1% to 2%, P = 0.039) at 7 min after termination of the interventions. The interventions reduced transcutaneous carbon dioxide partial pressure by similar amounts.

Conclusions: This trial adds to the evidence against the use of positive expiratory pressure therapy after abdominal surgery. It is even slightly better to read aloud.

Introduction: Fibrillar collagens accumulate in the breast cancer stroma and appear as poorly defined spiculated masses in mammography imaging. The prognostic value of tissue type I collagen remains elusive in treatment-naïve and chemotherapy-treated breast cancer patients. Here, type I collagen mRNA and protein expression were analysed in 2 large independent breast cancer cohorts. Levels were related to clinicopathological parameters, prognostic biomarkers, and outcome.

Method: COL1A1 mRNA expression was analysed in 2509 patients with breast cancer obtained from the cBioPortal database. Type I collagen protein expression was studied by immunohistochemistry in 1395 women diagnosed with early invasive breast cancer.

Results: Low COL1A1 mRNA and protein levels correlated with poor prognosis features, such as hormone receptor negativity, high histological grade, triple-negative subtype, node positivity, and tumour size. In unadjusted analysis, high stromal type I collagen protein expression was associated with improved overall survival (OS) (HR = 0.78, 95% CI = 0.61-0.99, p = .043) and trended towards improved breast cancer–specific survival (BCSS) (HR = 0.65, 95% CI = 0.42-1.01, P = 0.053), although these findings were lost after adjustment for other clinical variables. In unadjusted analysis, high expression of type I collagen was associated with better OS (HR = 0.70, 95% CI = 0.55-0.90, P = .006) and BCSS (HR = 0.55, 95% CI = 0.34-0.88, P = .014) among patients not receiving chemotherapy. Strikingly, the opposite was observed among patients receiving chemotherapy. There, high expression of type I collagen was instead associated with worse OS (HR = 1.83, 95% CI = 0.65-5.14, P = .25) and BCSS (HR = 1.72, 95% CI = 0.54-5.50, P = .357).

Conclusion: Low stromal type I collagen mRNA and protein expression are associated with unfavourable tumour characteristics in breast cancer. Stromal type I collagen might predict chemotherapy response.

Background: Breast cancer is the most common cancer in women. Cancer cells can persist in a prolonged dormant state for years without any clinical evidence of disease creating an urgent need to better understand the molecular mechanisms leading to relapse. This study aimed to identify extracellular matrix (ECM) components associated with hypoxia-induced breast cancer dormancy. The effects of selected ECM proteins on breast cancer cell proliferation were analyzed, along with their correlation with established prognostic markers in human breast cancer tissue.

Materials and methods: Screening of extracellular matrix proteins was performed in hypoxia-induced dormant MCF-7 breast cancer cells. Proliferation of MCF-7 cells in vitro was subsequently determined in the presence of recombinant ColVII. Adipose tissue-derived mesenchymal stem cells (AdMSCs) subpopulation overexpressing ColVII were indirectly isolated by ColVII receptor integrin-α6 specific antibodies. AdMSCs- MCF-7 3D spheroid cultures were generated to model solid tumour conditions. In addition, the association between ColVII and various prognostic markers was evaluated in clinical samples of human breast cancer tissue.

Results: Dormant MCF-7 cells showed an elevated expression of ColVII while MCF-7 cells cultured on ColVII exhibited reduced proliferation in vitro. In AdMSCs-MCF-7 3D spheroids, a reduced proliferation of MCF-7 cells was observed in Int-α6+/ ColVIIhigh compared with Int-α6-/ ColVIIlow AdMSCs spheroids. In human tissue, high ColVII expression correlated to several positive prognostic markers. Staining for Cytokeratin-5 revealed that ColVIIhigh-expressing cells were predominantly myoepithelial cells.

Conclusion: ColVII is associated with reduced proliferation of breast cancer cells in vitro. ColVII is strongly expressed in myoepithelial cells and in breast cancer tissue the high ColVII expression correlates with several well-known positive prognostic markers, highlighting its potential as a prognostic marker in breast cancer.

Background: A previously published study at Norrland University Hospital, Umeå, Sweden, found that in 29.5% of patients with urinary bladder cancer (UBC) who underwent cystectomy, incorrect cT-stage (clinical T-stage) was registered in the Swedish National Register of Urinary Bladder Cancer (SNRUBC). Tumor in bladder diverticulum (TIBD) and tumor-associated hydronephrosis (TAH) were common causes for misclassification. Our aim was to further investigate cT-staging, as well as pathoanatomical markers, in the SNRUBC, compared to detailed data from medical records in a larger, retrospective multicenter cohort. Our secondary objective was to describe the frequency of pathoanatomical markers in pathology reports (PAD) after transurethral resection of the bladder (TURb): variant histology (VH), concomitant carcinoma in situ (CIS), lymphovascular invasion (LVI) and perineural invasion (PNI).

Methods: Medical records of 630 patients planned for radical cystectomy in the years 2009-2022 in the Northern Healthcare Region, Region of Gävleborg and Region of Västmanland were reviewed. Factors impacting risk of misclassification of cT-staging were identified through logistic regression. In TURb pathology reports, all comments on pathoanatomical markers were identified. For each pathoanatomical marker, respectively, comments were then registered as positive or negative. The absence of a comment on a marker was registered as "not commented".

Results: A total discrepancy rate of 36.5% was found between validated cT-staging and the SNRUBC, of which 13.3% were upstaged from <T2 to ≥T2. The results are presented as odds ratios (ORs) with corresponding 95% confidence intervals (CIs). Registrations with discrepancy were significantly associated with TIBD (OR: 10.28, 95% CI: 5.20-20.34), TAH (OR: 9.60, 95% CI: 6.12-15.10) and year of cystectomy 2009-2011 (OR: 3.38, 95% CI: 2.13-5.36). Incorrect CIS registration: 134 (35.8%); incorrect histology registration: 98 (25.6%). Total frequencies of recorded pathoanatomical markers in TURb-reports were for VH =23.8%, concomitant CIS =36.9%, LVI =30.4%, PNI =2.3%.

Conclusions: The SNRUBC has a significant prevalence of misclassification of cT-staging with a large proportion due to TAH and TIBD. Misclassification of VH and CIS is also common. Improved guidelines could increase consistency. Total rates of recorded pathoanatomical markers in TURb-reports are low.

BACKGROUND: In Sweden, all patients with urinary bladder cancer (UBC) are recorded in the Swedish National Register for Urinary Bladder Cancer (SNRUBC). The purpose of this study was to validate the registered clinical tumour categories (cT-categories) in the SNRUBC for Norrland University Hospital, Sweden, from 2009 to 2020, inclusive.

METHODS: The medical records of all 295 patients who underwent radical cystectomy for the treatment of UBC were reviewed retrospectively. Possible factors impacting the cT-categories were identified. To optimise cT-classification, computed tomography urography of all patients with suspected tumour-associated hydronephrosis (TAH) or suspected tumour in bladder diverticulum (TIBD) were retrospectively reviewed by a radiologist. Discrepancy was tested with a logistic regression model.

RESULTS: cT-categories differed in 87 cases (29.5%). Adjusted logistic regression analysis found TIBD and TAH as significant predictors for incorrect registration; OR = 7.71 (p < 0.001), and OR = 17.7, (p < 0.001), respectively. In total, 48 patients (68.6%) with TAH and 12 patients (52.2%) with TIBD showed discrepancy regarding the cT-category. Incorrect registration was mostly observed during the years 2009-2012.

CONCLUSION: The study revealed substantial incorrect registration of cT-categories in SNRUBC. A major part of the misclassifications was related to TAH and TIBD. Registration of these variables in the SNRUBC might be considered to improve correct cT-classification.

Aim: To investigate whether patients with endoscopically untraversable rectal cancer may benefit from a defunctioning stoma created before neoadjuvant therapy or resectional surgery.

Methods: This retrospective study comprise patients diagnosed with rectal cancer during 2007–2020 in Region Västerbotten, Sweden. The primary outcome was time between diagnosis and any treatment, while survival and the incidence of complications were secondary outcomes. Excluded were patients without endoscopic obstruction, patients already having a stoma, patients with recurrent disease, palliative patients, and patients receiving a stoma shortly after diagnosis due to any urgent bowel-related complication. Data were obtained from the Swedish Colorectal Cancer Registry and medical records. Kaplan–Meier failure curves were drawn, and a multivariable Cox regression model was employed for confounding adjustment.

Results: Out of 843 patients, 57 remained after applying exclusion criteria. Some 12/57 (21%) patients received a planned stoma before treatment, and the remainder received upfront neoadjuvant therapy or surgery. Median time to any treatment was 51 days for the planned stoma group and 36 days for the control group, with an adjusted hazard ratio of 0.28 (95% confidence interval: 0.12–0.64). Complications occurred at a rate of 5/12 (42%) and 7/45 (16%) in the planned stoma group and control group, respectively. Survival was similar between groups.

Conclusion: A planned stoma results in treatment delay, but it remains unclear whether this is clinically relevant. Complications were more common in the planned stoma group, although the data are limited. While larger studies are needed, it seems feasible to avoid defunctioning stomas even in endoscopically obstructing rectal cancers.

Objective: Vehicle materials developments raise concerns about new patterns of vehicle fire toxic gas emissions. This study aimed to describe toxicologic components in a recent material of fatal car crashes on Swedish roads in which the vehicle caught fire and compare the results to a previous material.

Methods: Retrospective registry study. All fatal car crashes with fire in Sweden 2009–2018 were extracted from the Swedish Transport Administration’s In-Depth Studies Database and compared with an earlier study of the time period 1998–2008.

Results: A total of 79 crashes and 94 fatalities were included. Carbon monoxide (COHb) blood levels >10% were found in 13 cases. Hydrogen cyanide (HCN) blood levels 0.1–1.7 µg/g were found in 10 cases. In 31 of the cases the person had a blood alcohol level (BAC) >0.2‰, which is the legal driving limit in Sweden. A total of 15 people died due to burn injuries and 2 individuals died due to toxic gas emissions without any other fatal traumatic injury. Total number of deaths in fire-related crashes halved from 181 (1998–2008) to 94 (2009–2018) but the percentage of fatalities in burning vehicles was unaltered (5% vs. 6%). The proportion of fatalities with HCN in the blood increased from 2% between 1998–2008 to 10% during 2009–2018 (p = 0.006). The age of the car involved in a crash increased by 0.26 years per calendar year (p = 0.001).

Conclusions: The proportion of fatalities with measured levels of HCN in the blood has increased. Eleven of the 15 burn injury fatalities had high levels of alcohol, HCN, or COHb, possibly contributing to an inability to leave a burning vehicle. Faster rescue brought by improved specific education and training of ambulance and rescue services personnel may be of future importance, as may on-scene antidote administration and revised regulations of vehicle flammability.

Objectives: Intraoperative pancreatoscopy is a promising procedure that might guide surgical resection for suspected main duct (MD) and mixed type (MT) intraductal papillary mucinous neoplasms (IPMNs). The aim of the present study was to assess the diagnostic yield and clinical impact of intraoperative pancreatoscopy in patients operated on for MD and MT-IPMNs.

Methods: This is a retrospective cohort study. Patients undergoing surgery for suspected MD or MT-IPMN underwent intraoperative pancreatoscopy and frozen section analysis. In all patients who required extended resection due to pancreatoscopic findings, we compared the final histology with the results of the intraoperative frozen section analysis.

Results: In total, 46 patients, 48% females, mean age (range) 67 years (45–82 years) underwent intraoperative pancreatoscopy. No mortality or procedure related complications were observed. Pancreatoscopy changed the operative course in 30 patients (65%), leading to extended resections in 20 patients (43%) and to parenchyma sparing procedures in 10 patients (22%). Analyzing the group of patients who underwent extended resections, 7 (35%) displayed lesions that needed further surgical treatment (six high grade dysplasia and one with G1 pancreatic neuroendocrine tumor) and among those 7, just 1 (14%) would have been detected exclusively with histological frozen section analysis of the transection margin. The combination of both pancreatoscopy and frozen section analysis lead to 86% sensitivity and 92% specificity for the detection of pathological tissue in the remnant pancreas.

Conclusion: Intraoperative pancreatoscopy is a safe and feasible procedure and might allow the detection of skip lesions during surgery for suspect MD-involving IPMNs.