Publications by authors named "Johan Richter"

Background: Brain tumor needle biopsy interventions are inflicted with nondiagnostic or biased sampling in up to 25% and hemorrhage, including asymptomatic cases, in up to 60%. To identify diagnostic tissue and sites with increased microcirculation, intraoperative optical techniques have been suggested. The aim of this study was to investigate the clinical implications of in situ optical guidance in frameless navigated tumor biopsies.

View Article and Find Full Text PDF

The advent of tyrosine kinase inhibitors (TKIs) as treatment of chronic myeloid leukemia (CML) is a paradigm in molecularly targeted cancer therapy. Nonetheless, TKI-insensitive leukemia stem cells (LSCs) persist in most patients even after years of treatment and are imperative for disease progression as well as recurrence during treatment-free remission (TFR). Here, we have generated high-resolution single-cell multiomics maps from CML patients at diagnosis, retrospectively stratified by BCR::ABL1 (%) following 12 months of TKI therapy.

View Article and Find Full Text PDF

Laser Doppler flowmetry (LDF) is a well-established technique for the investigation of tissue microcirculation. Compared to skin, the use in the human brain is sparse. The measurement of cerebral microcirculation in neurointensive care and during neurosurgery is challenging and requires adaptation to the respective clinical setting.

View Article and Find Full Text PDF

Limited data is available on the health-related quality of life (HRQoL) and symptoms of patients with chronic myeloid leukemia (CML) who are in treatment-free remission (TFR). We herein report HRQoL results from the EURO-SKI trial. Patients who had been on tyrosine kinase inhibitors (TKIs) therapy for at least 3 years and achieved MR4 for at least 1 year were enrolled from 11 European countries, and the EORTC QLQ-C30 and the FACIT-Fatigue questionnaires were used to assess HRQoL and fatigue respectively.

View Article and Find Full Text PDF
Article Synopsis
  • - The EURO-SKI study, the largest clinical trial on stopping tyrosine kinase inhibitors (TKIs) for chronic myeloid leukemia, involved 728 patients and found that 61% maintained major molecular response (MMR) at 6 months and 46% at 36 months.
  • - Key factors influencing MMR maintenance included the length of TKI treatment and the patient's deep molecular remission duration before stopping treatment, along with the type of leukemia transcript.
  • - For patients experiencing late MMR losses, factors like TKI treatment duration, the presence of blasts in blood, and platelet counts at diagnosis were significant predictors of outcomes during the 36-month follow-up.
View Article and Find Full Text PDF
Article Synopsis
  • * The DAstop2 study examined patients who previously failed a treatment-free remission (TFR) attempt, re-treating them with dasatinib for two years and assessing their ability to stop TKIs again.
  • * Results showed that 61%, 56%, and 46% of patients maintained TFR at 6, 12, and 24 months after attempting a second stop, demonstrating that this approach is safe and effective for many patients.
View Article and Find Full Text PDF

Membrane transporters are important determinants of drug bioavailability. Their expression and activity affect the intracellular drug concentration in leukemic cells impacting response to therapy. Pharmacogenomics represents genetic markers that reflect allele arrangement of genes encoding drug transporters associated with treatment response.

View Article and Find Full Text PDF

Brain tumor needle biopsies are performed to retrieve tissue samples for neuropathological analysis. Although preoperative images guide the procedure, there are risks of hemorrhage and sampling of non-tumor tissue. This study aimed to develop and evaluate a method for frameless one-insertion needle biopsies with in situ optical guidance and present a processing pipeline for combined postoperative analysis of optical, MRI, and neuropathological data.

View Article and Find Full Text PDF

In order to improve molecular response for a discontinuation attempt in chronic myeloid leukemia (CML) patients in chronic phase, who had not achieved at least a molecular response <0.01% BCR-ABL1 (MR) after at least 2 years of imatinib therapy, we prospectively evaluated whether they could attain MR after a switch to a combination of nilotinib and 9 months of pegylated interferon-α2b (PegIFN). The primary endpoint of confirmed MR at month 12 (a BCR-ABL1 level ≤ 0.

View Article and Find Full Text PDF

Background: Stereotactic neurosurgical brain biopsies are afflicted with risks of inconclusive results and hemorrhage. Such complications can necessitate repeated trajectories and prolong surgical time.

Objective: To develop and introduce a 1-insertion stereotactic biopsy kit with direct intraoperative optical feedback and to evaluate its applicability in 3 clinical cases.

View Article and Find Full Text PDF

The field of spinal neurosurgery covers degenerative conditions and trauma as well as tumors, malformations and vascular disorders of spine and spinal cord. This article focuses on the Swedish spinal neurosurgical care regarding radiculopathy and myelopathy. Disc herniation, foraminal stenosis, spinal stenosis and spinal cord compression due to degenerative disorders or tumors are discussed.

View Article and Find Full Text PDF

In chronic myeloid leukemia (CML), combination therapies with tyrosine kinase inhibitors (TKIs) aim to improve the achievement of deep molecular remission that would allow therapy discontinuation. IFN-α is one promising candidate, as it has long-lasting effects on both malignant and immune cells. In connection with a multicenter clinical trial combining dasatinib with IFN-α in 40 patients with chronic-phase CML (NordCML007, NCT01725204), we performed immune monitoring with single-cell RNA and T cell receptor (TCR) sequencing (n = 4, 12 samples), bulk TCRβ sequencing (n = 13, 26 samples), flow cytometry (n = 40, 106 samples), cytokine analyses (n = 17, 80 samples), and ex vivo functional studies (n = 39, 80 samples).

View Article and Find Full Text PDF

Tyrosine kinase inhibitors (TKIs) have profoundly improved the clinical outcome for patients with chronic myeloid leukemia (CML), but their overall survival is still subnormal and the treatment is associated with adverse events. In a large cohort-study, we assessed the morbidity in 1328 Swedish CML chronic phase patients diagnosed 2002-2017 and treated with TKIs, as compared to that in carefully matched control individuals. Several Swedish patient registers with near-complete nationwide coverage were utilized for data acquisition.

View Article and Find Full Text PDF

In brain tumor surgery it is difficult to distinguish the marginal zone with the naked eye. Fluorescence techniques can help identifying tumor tissue in the zone during resection and biopsy procedures. In this paper a novel system for combined real-time measurements of PpIX-fluorescence, microcirculation and tissue grey-whiteness is presented and experimentally evaluated.

View Article and Find Full Text PDF

Objectives: Treatment-free remission (TFR) has emerged as a treatment goal in chronic myeloid leukemia in the chronic phase (CML-CP). Attempts to increase proportion of patients achieving TFR include combination of tyrosine kinase inhibitors (TKI) and other drugs. Interferon-α in addition to TKI has shown promising efficacy but with dose-dependent toxicity and discontinuations.

View Article and Find Full Text PDF

Background: Accurate stereotactic biopsies of brain tumors are imperative for diagnosis and tailoring of the therapy. Repetitive needle insertions enhance risks of brain lesioning, hemorrhage, and complications due to prolonged procedure.

Objective: To investigate clinical benefits of a combined 5-aminolaevulinic acid (5-ALA) fluorescence and laser Doppler flowmetry system for the detection of malignant brain tumor and blood vessels in stereotactic biopsies.

View Article and Find Full Text PDF

Clinical trials show that tyrosine kinase inhibitor (TKI) treatment can be discontinued in selected patients with chronic myeloid leukaemia (CML). Although updated CML guidelines support such procedure in clinical routine, data on TKI stopping outside clinical trials are limited. In this retrospective study utilising the Swedish CML registry, we examined TKI discontinuation in a population-based setting.

View Article and Find Full Text PDF

Infantile malignant osteopetrosis is a devastating disorder of early childhood that is frequently fatal and for which there are only limited therapeutic options. Gene therapy utilizing autologous hematopoietic stem and progenitor cells represents a potentially advantageous therapeutic alternative for this multisystemic disease. Gene therapy can be performed relatively rapidly following diagnosis, will not result in graft versus host disease, and may also have potential for reduced incidences of other transplant-related complications.

View Article and Find Full Text PDF

Background: Whilst modern awake intraoperative mapping has been widely accepted and implemented in the last decades in neuro-oncology, sparse reports have been published on the safety and efficiency of this approach in epilepsy surgery.

Method: This article reports four cases with different locations of epileptogenic zones as examples of possible safe and efficient resections.

Result: The results of the resections on seizure control were Engel 1 (no disabling seizures) in all cases and no patient experienced significant neurological deficits.

View Article and Find Full Text PDF

Background: Infantile malignant osteopetrosis (IMO) is an autosomal recessive disorder characterized by non-functional osteoclasts and a fatal outcome early in childhood. About 50% of patients have mutations in the TCIRG1 gene.

Methods: IMO iPSCs were generated from a patient carrying a homozygous c.

View Article and Find Full Text PDF

Several studies have now shown that chronic myeloid leukaemia (CML) patients in deep molecular remission may discontinue tyrosine kinase inhibitor (TKI) treatment with a treatment free remission (TFR) rate of approximately 40-60 %. Some factors influencing the possibility of TFR have been described but better tools are needed for individual prediction of long-term TFR. Herein, two multiplex panels were utilised to analyse a total of 162 different plasma proteins from 56 patients included in the TKI stopping trial EURO-SKI (Saussele et al.

View Article and Find Full Text PDF
Article Synopsis
  • The study investigates whether chronic infections could be a risk factor for chronic myeloid leukemia (CML), building on previous findings linking peptic ulcers to increased CML risk.
  • Researchers conducted a case-control study using Swedish registry data, analyzing 980 CML patients and 4,960 matched controls to explore associations between previous infections and CML incidence.
  • Results showed that diagnoses related to peptic ulcers and the use of proton pump inhibitors were linked to a significantly higher risk of CML, suggesting a potential common background between gastric issues and CML, warranting further investigation.
View Article and Find Full Text PDF