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Objectives: FDG PET/MRI is a promising imaging modality for nodal staging in rectal cancer; however, its role remains to be defined. We aimed to assess its performance in detecting mesorectal malignant lymph node involvement based on both metabolic and morphological criteria at PET/MRI versus at MRI alone.

Materials & methods: Sixty-five patients (median age 70 years, IQR 61–74; 39 men) were examined with FDG PET/MRI followed by individual anatomical matching of mesorectal nodal structures between histopathology and MRI. PET N-stage assessment was evaluated using FDG uptake over background levels, MRI N-stage by the 2016 European Society of Gastrointestinal and Abdominal Radiology (ESGAR) consensus criteria and PET/MRI was evaluated using both in combination. Histopathological assessment served as gold standard, and the accuracy of identifying malignancy at both nodal and patient level was calculated. Furthermore, FDG PET/MRI and MRI using ESGAR criteria for nodal restaging after neoadjuvant treatment were also evaluated.

Results: In total, 835 nodal structures were matched, of which 104 were malignant (12%); among these, 59/104 (57%) were histopathologically proven lymph node metastases. MRI alone yielded a sensitivity of 54% and specificity of 85% for nodal malignancy, while the corresponding estimates for FDG-avidity gave a 75% sensitivity and 79% specificity. The different combined FDG PET/MRI criteria for malignancy were evaluated: FDG-positivity or malignancy according to ESGAR criteria resulted in a sensitivity of 76%; while the combination of FDG-positivity and malignancy according to ESGAR criteria achieved a specificity of 90%.

Conclusion: Compared to MRI alone, FDG PET/MRI offers potential added value by reducing the risk of nodal understaging.

Purpose: To evaluate current MRI-based criteria for malignancy in mesorectal nodal structures in rectal cancer.

Method: Mesorectal nodal structures identified on baseline MRI as lymph nodes were anatomically compared to their corresponding structures histopathologically, reported as lymph nodes, tumour deposits or extramural venous invasion. All anatomically matched nodal structures from patients with primary surgery and all malignant nodal structures from patients with neoadjuvant treatment were included. Mixed-effects logistic regression models were used to evaluate the morphological criteria irregular margin, round shape, heterogeneous signal and nodal size, as well as the combined 2016 European Society of Gastrointestinal and Abdominal Radiology (ESGAR) consensus criteria, with histopathological nodal status as the gold standard.

Results: In total, 458 matched nodal structures were included from 46 patients (mean age, 67.7 years ± 1.5 [SD], 27 men), of which 19 received neoadjuvant treatment. The strongest associations in the univariable model were found for short-axis diameter ≥ 5 mm (OR 21.43; 95% CI: 4.13–111.29, p < 0.001) and heterogeneous signal (OR 9.02; 95% CI: 1.33–61.08, p = 0.024). Only size remained significant in multivariable analysis (OR 12.32; 95% CI: 2.03–74.57, p = 0.006). When applying the ESGAR consensus criteria to create a binary classification of nodal status, the OR of malignant outcome for nodes with positive ESGAR was 8.23 (95% CI: 2.15–31.50, p = 0.002), with corresponding sensitivity and specificity of 54% and 85%, respectively.

Conclusion: The results confirm the role of morphological and size criteria in predicting lymph node metastases. However, the current criteria might not be accurate enough for nodal staging.

Objective: This study uses retrospective longitudinal data from a large unselected cohort of patients with peripheral facial paralysis to determine the prevalence and patient characteristic predictors of sequelae receiving intervention.

Study Design: Retrospective case review.

Setting: Karolinska University Hospital in Stockholm Sweden serves as the only tertiary facial palsy center in the region. Here, patients are diagnosed, are followed up, and undergo all major interventions.

Patients: All adult patients presenting with peripheral facial palsy due to idiopathic, zoster, or Borrelia origin at Karolinska, January 1, 2010 to December 31, 2011 with follow-up until December 2022.

Interventions: Patient charts were studied to identify patient characteristics, etiology, initial treatment, severity of palsy, and treatments targeting sequelae.

Main Outcome: Measures Types of initial and late treatments were noted. Sunnybrook and/or House-Brackmann scales were used for palsy grading.

Results: Five hundred twenty-five patients were included. Thirty-three patients (6.3%) received botulinum toxin injections and/or surgical treatment. In this subgroup, 67% received corticosteroids compared to 85% of all patients (p = 0.005), cardiovascular disease prevalence was higher (23 and 42%, respectively, p = 0.009). For 81 patients (15%), follow-up was discontinued although the last measurement was Sunnybrook less than 70 or House-Brackmann 3 to 6.

Conclusions: Of patients with peripheral facial palsy, 6.3% underwent injections and/or surgical treatment within 12 years. However, due to a rather large proportion not presenting for follow-up, this might be an underestimation. Patients receiving late injections and/or surgical treatment had more comorbidities and received corticosteroid treatment to a significantly lower extent in the acute phase of disease.

AIM: The aim of this study was to investigate if patients with a weak social network and colon cancer are more likely to be operated as an emergency than those with a strong social network.

METHODS: Data from patients living in Västerbotten County, Sweden, who underwent colon cancer surgery between 2007 and 2020 were extracted from the Swedish Colorectal Cancer Registry (SCRCR). Patients identified were matched against the Västerbotten Intervention Program (VIP) and the longitudinal study Monitoring of Trends and Determinants in Cardiovascular Disease (MONICA). These two databases include a survey that includes questions regarding quality and size of the patient's social network. Multivariable logistic regression was used for analysis.

RESULTS: Six items from the questions on social network, and the composite variables availability of social integration (AVSI) and availability of attachment (AVAT) were analysed. Data from 801 patients were analysed. The odds ratio for emergency surgery was significantly higher for divorced patients (OR 2.01 (CI 1.03-3.91)) and for male gender (OR 1.51 (CI 1.02-2.24)). A higher OR was seen amongst those with no-one to share feelings with (OR 1.57 (CI 0.82-3.03)) or to comfort them (OR1.33 (CI 0.78-2.28)). Quantitative aspects of social life such as the number of people greater than 10 that feel relaxed at the patient's home, showed a lower OR (OR 0.71(CI 0.35-1.43)).

CONCLUSION: The impact of social network on the risk for emergency surgery for colon cancer is limited. Divorced status and male gender were associated with an increased risk for emergency surgery.

PURPOSE: Anterior resection is the procedure of choice for tumours in the mid and upper rectum. Depending on tumour height, a total mesorectal excision (TME) or partial mesorectal excision (PME) can be performed. Low anastomoses in particular have a high risk of developing anastomotic leakage, which might be explained by blood perfusion compromise. A pilot study indicated a worse blood flow in TME patients in an open setting. The aim of this study was to further evaluate perianastomotic blood perfusion changes in relation to TME and PME in a predominantly laparoscopic context.

METHOD: In this prospective cohort study, laser Doppler flowmetry was used to evaluate the perianastomotic colonic and rectal perfusion before and after surgery. The two surgical techniques were compared in terms of mean differences of perfusion units using a repeated measures ANOVA design, which also enabled interaction analyses between type of mesorectal excision and location of measurement. Anastomotic leakage until 90 days after surgery was reported for descriptive purposes.

RESULTS: Some 28 patients were available for analysis: 17 TME and 11 PME patients. TME patients had a reduced blood perfusion postoperatively compared to PME patients in the aboral posterior area (mean difference: -57 vs 18 perfusion units; p = 0.010). An interaction between mesorectal excision type and anterior/posterior location was detected at the aboral level (p = 0.007). Two patients developed a minor leakage, diagnosed after discharge.

CONCLUSION: Patients operated on using TME have a decreased blood flow in the aboral posterior quadrant of the rectum postoperatively compared to patients operated on using PME. This might explain differing rates of anastomotic leakage.

TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT02401100.

Purpose: The primary aim of this study was to see whether perianal abscess rate differs between patients with type 1 and type 2 diabetes. A secondary aim was to determine whether poor glycemic control increases the risk for perianal abscess.

Methods: Data from the Swedish National Diabetes Registry and the Swedish National Patient Registry between January 2008 and June 2015 were matched. The risk for anal abscess was evaluated in univariate and multivariate analyses with type of diabetes, HbA1c level, BMI, and various diabetes complications as independent factors.

Results: Patients with type 1 diabetes had a lower rate of perianal abscess than patients with type 2 diabetes when adjusted for HbA1c, sex, and age (OR 0.65; 95% CI 0.57–0.73). The risk for perianal abscess increased with higher HbA1c. Incidence of perianal abscess was also elevated in diabetes patients with complications related to poor glycemic control such as ketoacidosis and coma (OR 2.63; 95% CI 2.06–3.35), gastroparesis, and polyneuropathy (OR 1.81; 95% CI 1.41–2.32).

Conclusions: The prevalence of perianal abscess was higher among patients with type 2 diabetes than those with type 1, suggesting that metabolic derangement may be more important than autoimmune factors. Poor glycemic control was associated with higher risk for perianal abscess.

Purpose: To enable the evaluation of locoregional disease in the on-going RECTOPET (REctal Cancer Trial on PET/MRI/CT) study; a methodology to match mesorectal imaging findings to histopathology is presented, along with initial observations.

Methods: FDG-PET/MRI examinations were performed in twenty-four consecutively included patients with rectal adenocarcinoma. In nine patients, of whom five received neoadjuvant treatment, a postoperative MRI of the surgical specimen was performed. The pathological cut-out was performed according to clinical routine with the addition of photo documentation of each slice of the surgical specimen, meticulously marking the location, size, and type of pathology of each mesorectal finding. This allowed matching individual nodal structures from preoperative MRI, via the specimen MRI, to histopathology.

Results: Preoperative MRI identified 197 mesorectal nodal structures, of which 92 (47%) could be anatomically matched to histopathology. Of the matched nodal structures identified in both MRI and histopathology, 25% were found to be malignant. These malignant structures consisted of lymph nodes (43%), tumour deposits (48%), and extramural venous invasion (9%). One hundred eleven nodal structures (55%) could not be matched anatomically. Of these, 97 (87%) were benign lymph nodes, and 14 (13%) were malignant nodal structures. Five were malignant lymph nodes, and nine were tumour deposits, all of which had a short axis diameter < 5 mm.

Conclusions: We designed a method able to anatomically match and study the characteristics of individual mesorectal nodal structures, enabling further research on the impact of each imaging modality. Initial observations suggest that small malignant nodal structures assessed as lymph nodes in MRI often comprise other forms of mesorectal tumour spread.

Trial registration: Clinical Trials Identifier: NCT03846882.

PurposeThe role of hybrid imaging using F-18-fluoro-2-deoxy-D-glucose positron-emission tomography (FDG-PET), computed tomography (CT) and magnetic resonance imaging (MRI) to improve preoperative evaluation of rectal cancer is largely unknown. To investigate this, the RECTOPET (REctal Cancer Trial on PET/MRI/CT) study has been launched with the aim to assess staging and restaging of primary rectal cancer. This report presents the study workflow and the initial experiences of the impact of PET/CT on staging and management of the first patients included in the RECTOPET study.MethodsThis prospective cohort study, initiated in September 2016, is actively recruiting patients from Region Vasterbotten in Sweden. This pilot study includes patients recruited and followed up until December 2017. All patients had a biopsy-verified rectal adenocarcinoma and underwent a minimum of one preoperative FDG-PET/CT and FDG-PET/MRI examination. These patients were referred to the colorectal cancer multidisciplinary team meeting at Umea University Hospital. All available data were evaluated when making management recommendations. The clinical course was noted and changes consequent to PET imaging were described; surgical specimens underwent dedicated MRI for anatomical matching between imaging and histopathology.ResultsTwenty-four patients have so far been included in the study. Four patients were deemed unresectable, while 19 patients underwent or were scheduled for surgery; one patient was enrolled in a watch-and-wait programme after restaging. Consequent to taking part in the study, two patients were upstaged to M1 disease: one patient was diagnosed with a solitary hepatic metastasis detected using PET/CT and underwent metastasectomy prior to rectal cancer surgery, while one patient with a small, but metabolically active, lung nodulus experienced no change of management. PET/MRI did not contribute to any recorded change in patient management.ConclusionsThe RECTOPET study investigating the role of PET/CT and PET/MRI for preoperative staging of primary rectal cancer patients will provide novel data that clarify the value of adding hybrid to conventional imaging, and the role of PET/CT versus PET/MRI.Trial registrationNCT03846882.

Purpose: The purpose of this study is to see if the distance to a hospital performing colon cancer surgery is a risk factor for emergency surgical intervention and to determine the variability between defined but demographically divergent catchment areas.

Methods: Data on patients living in Västerbotten County who underwent colon cancer surgery between 2007 and 2010 were extracted from the Swedish Colorectal Cancer Register (SCRCR). Of the 436 registrations matching these criteria, 380 patients were used in the analysis, and their distance to the nearest hospital providing care for colorectal cancer (CRC) was estimated using Google Maps™. The correlations between the risk for emergency surgery and the distance to a hospital, gender, age, income level and hospital catchment area were analysed in uni- and multivariate models.

Results: Distance to the nearest hospital had no significant effect on the proportion of emergency operations for colon cancer. There was significant variability in risk for emergency surgery between hospital catchment areas, where the catchment areas of the university hospital and the most rural hospital had a higher proportion than the other local hospital catchment area (OR, 2.00 (p = 0.038) and OR, 2.97 (p = 0.005)). These results were still significant when analysed with multivariate logistic regression (OR, 2.13 (p = 0.026) and OR, 3.05 (p = 0.013)).

Conclusion: Distance to a hospital performing colon cancer surgery had no effect on the proportion of emergency surgeries. However, a variability between defined catchment areas was seen. Future studies will focus on possible factors behind this variability.

INTRODUCTION: The aim of this study was to assess the impact of diabetes mellitus, Crohn's disease, HIV/aids, and obesity on the prevalence and readmission rate of perianal abscess.

METHODS: The study cohort was based on the Swedish National Patient Register and included all patients treated for perianal abscess in Sweden 1997-2009. The prevalence and risk for readmission were assessed in association with four comorbidity diagnoses: diabetes mellitus, Crohn's disease, HIV, and/or AIDS and obesity.

RESULTS: A total of 18,877 patients were admitted during the study period including 11,138 men and 4557 women (2.4:1). Crohn's disease, diabetes, and obesity were associated with a significantly higher prevalence of perianal abscess than an age- and gender-matched background population (p < 0.05). In univariate analysis, neither age nor gender had any significant impact on the risk for readmission. In a multivariate Cox proportional hazard analysis, Crohns disease was the only significant risk factor for readmission of perianal abscess.

CONCLUSION: Crohn's disease, diabetes, and obesity increase the risk for perianal abscess. Of these, Crohn's and HIV has an impact on readmission. The pathogenesis and the influence of diabetes and obesity need further research if we are to understand why these diseases increase the risk for perianal abscess but not its recurrence.