Lennart Blomqvist

Dr. Lennart Blomqvist


Research Focus & Metrics

Academic Career Length

30Years (1997-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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7 June 2013 in BMC Cancer
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Journal Article
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PNPer Johan Nilsson
Per Johan Nilsson
BEBoudewijn van Etten
Boudewijn van Etten
GHGeke AP Hospers
Geke AP Hospers
LPLars Påhlman
Lars Påhlman
CVCornelis J.H. van de Velde
Cornelis J.H. van de Velde
BGBengt Glimelius
Bengt Glimelius
Current standard for most of the locally advanced rectal cancers is preoperative chemoradiotherapy, and, variably per institution, postoperative adjuvant chemotherapy. Short-course preoperative radiation with delayed surgery has been shown to induce tumour down-staging in both randomized and observational studies. The concept of neo-adjuvant chemotherapy has been proven successful in gastric cancer, hepatic metastases from colorectal cancer and is currently tested in primary colon cancer. Patients with rectal cancer with high risk features for local or systemic failure on magnetic resonance imaging are randomized to either a standard arm or an experimental arm. The standard arm consists of chemoradiation (1.8 Gy x 25 or 2 Gy x 25 with capecitabine) preoperatively, followed by selective postoperative adjuvant chemotherapy. Postoperative chemotherapy is optional and may be omitted by participating institutions. The experimental arm includes short-course radiotherapy (5 Gy x 5) followed by full-dose chemotherapy (capecitabine and oxaliplatin) in 6 cycles before surgery. In the experimental arm, no postoperative chemotherapy is prescribed. Surgery is performed according to TME principles in both study arms. The hypothesis is that short-course radiotherapy with neo-adjuvant chemotherapy increases disease-free and overall survival without compromising local control. Primary end-point is disease-free survival at 3 years. Secondary endpoints include overall survival, local control, toxicity profile, and treatment completion rate, rate of pathological complete response and microscopically radical resection, and quality of life. Following the advances in rectal cancer management, increased focus on survival rather than only on local control is now justified. In an experimental arm, short-course radiotherapy is combined with full-dose chemotherapy preoperatively, an alternative that offers advantages compared to concomitant chemoradiotherapy with or without postoperative chemotherapy. In a multi-centre setting this regimen is compared to current standard with the aim of improving survival for patients with locally advanced rectal cancer. ClinicalTrials.gov NCT01558921

24 May 2022 in Biomolecules
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LBLennart Blomqvist
Lennart Blomqvist
GNGunnar F. F. Nordberg
Gunnar F. F. Nordberg
Valeria Marina NurchiValeria Marina Nurchi
Valeria Marina Nurchi
Jan O. AasethJan O. Aaseth
Jan O. Aaseth
Gadolinium (Gd) is one of the rare-earth elements. The properties of its trivalent cation (Gd3+) make it suitable to serve as the central ion in chelates administered intravenously to patients as a contrast agent in magnetic resonance imaging. Such Gd-chelates have been used for more than thirty years. During the past decades, knowledge has increased about potential harmful effects of Gd-chelates in patients with severe renal dysfunction. In such patients, there is a risk for a potentially disabling and lethal disease, nephrogenic systemic fibrosis. Restricting the use of Gd-chelates in persons with severely impaired renal function has decreased the occurrence of this toxic effect in the last decade. There has also been an increasing awareness of Gd-retention in the body, even in patients without renal dysfunction. The cumulative number of doses given, and the chemical structure of the chelate given, are factors of importance for retention in tissues. This review describes the chemical properties of Gd and its medically used chelates, as well as its toxicity and potential side effects related to injection of Gd-chelates.

19 January 2017 in Cancer Imaging
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ERErik Rollvén
Erik Rollvén
MAMirna Abraham-Nordling
Mirna Abraham-Nordling
THTorbjörn Holm
Torbjörn Holm
LBLennart Blomqvist
Lennart Blomqvist
To study different imaging criteria for prediction of lymph node metastases (Stage III disease) in colon cancer using CT. In a retrospective setting, 483 consecutive patients with histology proven colon cancer underwent elective primary resection during 2008–2011, a cohort of 119 patients were included. Contrast enhanced CT examinations, in portal-venous phase, were reviewed with assessment of the number of lymph nodes, their anatomical distribution, size, size ratio, internal heterogeneity, presence of irregular outer border and attenuation values. Sensitivity, specificity, PPV and NPV for each studied criteria for prediction of stage III disease was calculated. According to histopathology 80 patients were stage I-II and 39 were stage III. Of the studied CT-criteria for lymph node metastases per patient, internal heterogeneity in at least one lymph node resulted in the best performance with sensitivity, specificity, PPV and NPV of 79, 84, 70 and 89%, Odds ratio (OR) 20. Presence of irregular outer border resulted in a sensitivity, specificity, PPV and NPV of 59, 81, 61 and 82%, OR 6.2. If both internal heterogeneity and/or irregular outer border was used as a criterion this resulted in a sensitivity, specificity, PPV and NPV of 85, 75, 62 and 91%, OR 16.5. None of the size criteria used were predictive for stage III disease. When performing preoperative CT in patients with colon cancer, the imaging criteria that allow best prediction of stage III disease on CT are either presence of at least one lymph node with internal heterogeneity or internal heterogeneity and/or irregular outer border. These criteria have to be validated in a prospective study.

1 June 2013 in British Journal of Radiology
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Journal Article
Open access
HNH Nilsson
H Nilsson
LBLennart Blomqvist
Lennart Blomqvist
LDL Douglas
L Douglas
ANA Nordell
A Nordell
IJI Janczewska
I Janczewska
EJEduard Jonas
Eduard Jonas
The aims of this study were to use dynamic hepatocyte-specific contrast-enhanced MRI to evaluate liver volume and function in liver cirrhosis, correlate the results with standard scoring models and explore the inhomogeneous distribution of liver function in cirrhotic livers. 10 patients with liver cirrhosis and 20 healthy volunteers, serving as controls, were included. Hepatic extraction fraction (HEF), input relative blood flow and mean transit time were calculated on a voxel-by-voxel basis using deconvolutional analysis. Segmental and total liver volumes as well as segmental and total hepatic extraction capacity, expressed in HEFml, were calculated. An incongruence score (IS) was constructed to reflect the uneven distribution of liver function. The Mann-Whitney U-test was used for group comparison of the quantitative liver function parameters, liver volumes and ISs. Correlations between liver function parameters and clinical scores were assessed using Spearman rank correlation. Patients had larger parenchymal liver volume, lower hepatocyte function and more inhomogeneous distribution of function compared with healthy controls. The study demonstrates the non-homogeneous nature of liver cirrhosis and underlines the necessity of a liver function test able to compensate for the heterogeneous distribution of liver function in patients with diseased liver parenchyma. The study describes a new way to quantitatively assess the hepatic uptake of gadoxetate or gadolinium ethoxybenzyl diethylenetriaminepentaacetic acid in the liver as a whole as well as on a segmental level.

30 August 2016 in World Journal of Surgical Oncology
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EÖEmma Öistämö
Emma Öistämö
FHFredrik Hjern
Fredrik Hjern
LBLennart Blomqvist
Lennart Blomqvist
YFYlva Falkén
Ylva Falkén
KPKlas Pekkari
Klas Pekkari
MAMirna Abraham-Nordling
Mirna Abraham-Nordling
Emergency surgery for colon cancer, as a result of obstruction, has been vitiated by a high frequency of complications and poor survival. The concept of “bridge to surgery” includes either placement of self-expanding metallic stents (SEMS) or diverting stoma of an obstructing tumour and subsequent planned resection. The aim of this study was to compare acute resection with stoma or stent and later resection regarding surgical and oncological outcomes and total hospital stay. This is a retrospective cohort study. All 2424 patients diagnosed with colorectal cancer during 1997–2013 were reviewed. All whom underwent acute surgery with curative intention for left-sided malignant obstruction were included in the study. One hundred patients fulfilled the inclusion criteria. Among them, 57 patients were treated with acute resection and 43 with planned resection after either acute diverting colostomy (n = 23) or stent placement (n = 20). The number of harvested lymph nodes in the resected specimen was higher in the planned resection group compared with acute resection group (21 vs. 8.7; p = 0.001). Fewer patients were treated with adjuvant chemotherapy in the acute resection group than in the stoma group (14 % (8/57 patients) vs. 43 %, (10/23 patients; p = 0.024)). Patients operated with acute resection had a higher 30-day mortality rate and were more frequently left with a permanent stoma. Decompression of emergency obstructive left colon cancer with stent or stoma and subsequent curative resection appears safer and results in a higher yield of lymph node harvest, and fewer patients are left with a permanent stoma.

14 February 2019 in Abdominal Radiology
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ERErik Rollvén
Erik Rollvén
LBLennart Blomqvist
Lennart Blomqvist
EÖEmma Öistämö
Emma Öistämö
FHFredrik Hjern
Fredrik Hjern
GCGyörgy Csanaky
György Csanaky
MAMirna Abraham-Nordling
Mirna Abraham-Nordling
The aim of the study was to assess morphological predictors for lymph node metastases (Stage III disease) in colon cancer on computed tomography.