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"Mathiesen, Tiit"
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The risk of developing a meningioma during and after pregnancy
by
Tettamanti, Giorgio
,
Feychting, Maria
,
Talbäck, Mats
in
631/67/1922
,
631/67/2324
,
Brain cancer
2021
Pregnancy has been associated with diagnosis or growth of meningiomas in several case reports, which has led to the hypothesis that pregnancy may be a risk factor for meningiomas. The aim of this study was to test this hypothesis in a large population-based cohort study. Women born in Sweden 1958–2000 (N = 2,204,126) were identified and matched with the Medical Birth Register and the Cancer Register. The expected number of meningioma cases and risk ratios were calculated for parous and nulliparous women and compared to the observed number of cases. Compared to parous women, meningiomas were more common among nulliparous (SIR = 1.73; 95% CI 1.52–1.95). The number of meningioma cases detected during pregnancy was lower than the expected (SIR = 0.40; 95% CI 0.20–0.72). Moreover, no increased risk was found in the first-year post-partum (SIR = 1.04; 95% CI 0.74–1.41). Contrary to our hypothesis, there was no increased risk for diagnosing a meningioma during pregnancy or 1-year post-partum. A lower detection rate during pregnancy, may reflect under-utilization of diagnostic procedures, but the actual number of meningiomas was homogenously lower among parous than nulliparous women throughout the study period, indicating that pregnancy is not a risk factor for meningioma.
Journal Article
The Ki-67 Proliferation Index as a Marker of Time to Recurrence in Intracranial Meningioma
2020
Abstract
BACKGROUND
There are examples of incongruence between the WHO grade and clinical course in meningioma patients. This incongruence between WHO grade and recurrence has led to search for other prognostic histological markers.
OBJECTIVE
To study the correlation between the Ki-67 proliferative index (PI), risk of recurrence, and recurrence rates in meningioma patients.
METHODS
We prospectively collected pathological diagnosis of de novo consecutive meningiomas. In total, we followed 159 patients with clinical controls until recurrence, death, or emigration. We estimated the correlation between risk of recurrence and Ki-67 PI when adjusted for age at diagnosis, sex, WHO grade, extent of surgical resection, and tumor location. We estimated the cumulative incidence of recurrence when considering death without recurrence a competing risk. We report recurrence rates per 100 person-years.
RESULTS
A 1%-point increase of Ki-67 PI yielded a hazard ratio of 1.12 (95% CI: 1.01-1.24) in a multivariate analysis. The cumulative incidence of recurrence was 3% for Ki-67 0% to 4% vs 19% for Ki-67 > 4% meningiomas after 1 yr, but 24% vs 35%, respectively, after 10 yr. There was no significant difference in mean Ki-67 PI between nonrecurrent and recurrent meningioma in a 2-sample t-test (P = .08). The strongest relationship was detected between Ki-67 PI and time to recurrence: Ki-67 < 4% meningiomas recurred after median 4.8 yr, compared to 0.60 to 0.75 yr for patients with higher Ki-67 PI.
CONCLUSION
Ki-67 PI was a marker for time to recurrence rather than a predictor of recurrence. Ki-67 PI may be utilized for patient tailored follow-up.
Graphical Abstract
Graphical Abstract
Journal Article
Ten-year follow-up after Gamma Knife radiosurgery of meningioma and review of the literature
2020
ObjectivesWith regard to the generally slow growth of meningioma, it is essential to analyse clinical treatment results in a long-term perspective. The purpose of the present analysis is to provide clinical data after Gamma Knife radiosurgery of meningioma in a 10-year perspective together with a review of the current literature.MethodsThe current study is a retrospective analysis of 86 consecutive Swedish patients with meningiomas treated using Gamma Knife radiosurgery at the Karolinska Hospital Stockholm between March 1991 and May 2001. A total of 130 tumours were treated in 115 treatment sessions. The median radiological follow-up was 10 years (1.8–16.5 years), and the median clinical follow-up was 9.4 years (2.1–17.4 years).ResultsAfter a median follow-up period of 10 years, local tumour control was achieved in 87.8% of meningiomas (108/123 tumours). The median latency between initial treatment and local (in-field) recurrence (n = 15) was 5.8 years (1.9–11.5). Recurrences adjacent but outside the initial radiation field occurred in 15.1% of patients (13/86) at a median of 7.5 years (1.3–15.7). New meningiomas were seen in 10.5% after a median of 5.4 years (0.9–10.8). In 72% of patients, no further treatment was required, 17.4% (15/86) underwent a second Gamma Knife treatment, 4.7% (4/86) required later open surgery and 5.8% (5/86) required both secondary treatments. Eighty-six percent of patients were neurologically unchanged or improved. A significantly lower rate of local (in-field) recurrences was seen in meningiomas treated with a prescription dose of > 13.4 Gy (7.1% vs. 24%, p = 0.02).ConclusionsThe current retrospective analysis provides a 10-year follow-up and comprises one of the longest available follow-up studies of radiosurgically treated meningiomas. The current series documents a persistent high local tumour control after Gamma Knife treatment, while providing an estimation of a necessary minimum dose for long-term tumour control in meningiomas. The study confirms the validity of previous short-term data in a long-term perspective.
Journal Article
TERT promoter mutations in primary and secondary WHO grade III meningioma
2021
Purpose: TERT promoter mutation (TERTpMut) has a strong association to recurrence and has been suggested to act as a driver mutation for malignant transformation of WHO grade I and II meningiomas. TERTpMut has been investigated in selected high‐grade meningioma samples. The existence of TERTpMut across recurrent tumors in a population‐based cohort needs to be investigated in order to identify when TERTpMut emerges across recurrent samples and to validate prognostic impact among WHO grade III tumors. Methods: We gathered material from a consecutive single‐center cohort of 40 patients with malignant meningioma (WHO grade III) treated between 2000 and 2018, including specimens from primary and secondary malignant meningiomas with the corresponding earlier benign specimens and later malignant recurrences. In total 107 tumor samples were studied by Sanger sequencing for TERT promoter mutational status. Results: Seven of 40 patients (17.5%) harbored TERTpMut thus validating the incidence of TERTpMut in previous non‐population‐based cohorts. In 6/7 patients, the TERTpMut was present at initial surgery (WHO grade I–III) while in one patient the TERTpMut was found de novo when the meningioma became malignant. The incidences were 2/1.000.000/year for TERTpMut WHO grade III meningioma and 8/1.000.000/year for TERTpwt WHO grade III meningioma in our catchment area. We found a 1.7 times higher recurrence rate (CI 95% 0.65–4.44) and a 2.5 higher mortality rate per 10 person‐years (CI 95% 1.01–6.19) for TERTpMut compared to TERTpwt. Conclusion: TERTpMut can occur independently of malignant progression in meningioma and was most often present from the first tumor sample across recurring tumors. TERTpMut in WHO grade III may represent a marker of an aggressive subset of tumors. We investigated the TERT promoter mutation (TERTpMut) in a population‐based, consecutive cohort of 40 malignant meningioma patients with tumor samples available from the corresponding earlier benign specimens and later malignant recurrences. TERTpMut can occur independently of malignant progression in meningioma and was most often present from the first tumor sample across recurring tumors. TERTpMut in WHO grade III may represent a marker of an aggressive subset of tumors.
Journal Article
Cognitive dysfunction and subjective symptoms in patients with arachnoid cyst before and after surgery
by
Agopian-Dahlenmark Louiza
,
Mathiesen Tiit
,
Bergendal Åsa
in
Arachnoid
,
Brain diseases
,
Cognition
2020
IntroductionArachnoid cysts are congenital, benign lesions in the brain and are often incidental radiological findings. Frequently, the arachnoid cysts are left untreated; however, recent studies have shown that arachnoid cysts can cause cognitive dysfunction that affect quality of life. Moreover, the function can improve after surgical decompression. Hence, there is controversy regarding symptomatology and treatment effects of arachnoid cysts. The aim of the study was to analyse if arachnoid cysts can cause cognitive impairment and subjective symptoms and if these impairments are reversible after surgical treatment.Material and methodsTwenty-one consecutive patients with radiologically confirmed supratentorial arachnoid cysts were cognitively evaluated using a battery of seven neuropsychological tests. Twelve of these patients underwent surgery and were evaluated before and after surgery. The patients were also evaluated with neuropsychological testing after surgery. Further information was extracted from the medical records. The cognitive test results were compared to standard population values using z-test, and the test results from the surgically treated patients were compared before and after surgery using paired t-test.ResultsThe surgically treated patients had a statistically significant improvement of neurocognitive test results after surgery in six out of the seven tests (p < 0.05). The total patient group showed lower mean values in all tests when compared to standard population. Statistical significance was, however, only detected in two of the seven tests. All surgically treated patients reported diminished symptoms after surgery.ConclusionsThe patients with arachnoid cysts presented with cognitive dysfunction compared to the normal population which improved after surgical decompression. Arachnoid cysts should not be considered asymptomatic unless thoroughly evaluated with clinical and neuropsychological work-up.
Journal Article
Critical ICP thresholds in relation to outcome: Is 22 mmHg really the answer?
by
Riparbelli, Agnes C.
,
Olsen, Markus H.
,
Møller, Kirsten
in
Brain Injuries, Traumatic - diagnosis
,
Brain Injuries, Traumatic - therapy
,
Cognitive ability
2024
Purpose
Intensive care for patients with traumatic brain injury (TBI) aims, among other tasks, at avoiding high intracranial pressure (ICP), which is perceived to worsen motor and cognitive deficits and increase mortality. International recommendations for threshold values for ICP were increased from 20 to 22 mmHg in 2016 following the findings in a study by Sorrentino et al., which were based on an observational study of patients with TBI of averaged ICP values. We aimed to reproduce their approach and validate the findings in a separate cohort.
Methods
Three hundred thirty-one patients with TBI were included and categorised according to survival/death and favourable/unfavourable outcome at 6 months (based on Glasgow Outcome Score—Extended of 6–8 and 1—5, respectively). Repeated chi-square tests of survival and death (or favourable and unfavourable outcome) vs. high and low ICP were conducted with discrimination between high and low ICP sets at increasing values (integers) between 10 and 35 mmHg, using the average ICP for the entire monitoring period. The ICP limit returning the highest chi-square score was assumed to be the threshold with best discriminative ability. This approach was repeated after stratification by sex, age, and initial Glasgow Coma Score (GCS).
Results
An ICP limit of 18 mmHg was found for both mortality and unfavourable outcome for the entire cohort. The female and the low GCS subgroups both had threshold values of 18 mmHg; for all other subgroups, the threshold varied between 16 and 30 mmHg. According to a multiple logistic regression analysis, age, initial GCS, and average ICP are independently associated with mortality and outcome.
Conclusions
Using identical methods and closely comparable cohorts, the critical thresholds for ICP found in the study by Sorrentino et al. could not be reproduced.
Journal Article
Orthotopic meningioma rat model exhibits morphological and immunohistochemical congruency and epigenetic concordance with benign primary patient-derived tumors
by
Kristensen, Bjarne Winther
,
Boldt, Henning
,
Wirenfeldt, Martin
in
631/67/70
,
692/308/1426
,
692/308/2778
2024
Meningiomas are the most common primary central nervous system tumor. Clinical trials have failed to support effective medical treatments, despite initially promising animal studies. A key issue could be that available experimental models fail to mimic the clinical situation. Hence, there is a need for meningioma models with high translational value for understanding pathophysiology and tests of possible medical treatments. Resemblance between models and clinical meningiomas should be optimized with respect to morphology, immunohistochemistry and epigenetic factors, which we aimed to do. Third passage primary patient-derived benign meningiomas were implanted intracranially in athymic nude rats. The animals were euthanized after three months. We found intra- and intertumoral variability in terms of tumor take rate (79.5% for superficially implanted cells and 25% for deeply implanted cells) and xenograft sizes. There were close resemblance between primary tumors and xenografts in morphology and immunohistochemistry. Furthermore, we performed DNA-methylation using the EPIC 850 K array on three pairs of primary tumors and xenografts. Copy number variation profiles and correlation plots on CpGs showed a high degree of similarities between primary tumors and corresponding xenografts. On differential methylation analysis, most probes were insignificant (866,074), 25 were hypermethylated, and 382 were hypomethylated, where no significant differentially methylated regions were revealed.
Journal Article
Meningioma animal models: a systematic review and meta-analysis
by
Paludan-Müller, Asger Sand
,
Kristensen, Bjarne Winther
,
Wirenfeldt, Martin
in
Analysis
,
Animal genetic engineering
,
Animal models
2023
Background
Animal models are widely used to study pathological processes and drug (side) effects in a controlled environment. There is a wide variety of methods available for establishing animal models depending on the research question. Commonly used methods in tumor research include xenografting cells (established/commercially available or primary patient-derived) or whole tumor pieces either orthotopically or heterotopically and the more recent genetically engineered models—each type with their own advantages and disadvantages. The current systematic review aimed to investigate the meningioma model types used, perform a meta-analysis on tumor take rate (TTR), and perform critical appraisal of the included studies. The study also aimed to assess reproducibility, reliability, means of validation and verification of models, alongside pros and cons and uses of the model types.
Methods
We searched Medline, Embase, and Web of Science for all in vivo meningioma models. The primary outcome was tumor take rate. Meta-analysis was performed on tumor take rate followed by subgroup analyses on the number of cells and duration of incubation. The validity of the tumor models was assessed qualitatively. We performed critical appraisal of the methodological quality and quality of reporting for all included studies.
Results
We included 114 unique records (78 using established cell line models (ECLM), 21 using primary patient-derived tumor models (PTM), 10 using genetically engineered models (GEM), and 11 using uncategorized models). TTRs for ECLM were 94% (95% CI 92–96) for orthotopic and 95% (93–96) for heterotopic. PTM showed lower TTRs [orthotopic 53% (33–72) and heterotopic 82% (73–89)] and finally GEM revealed a TTR of 34% (26–43).
Conclusion
This systematic review shows high consistent TTRs in established cell line models and varying TTRs in primary patient-derived models and genetically engineered models. However, we identified several issues regarding the quality of reporting and the methodological approach that reduce the validity, transparency, and reproducibility of studies and suggest a high risk of publication bias. Finally, each tumor model type has specific roles in research based on their advantages (and disadvantages).
Systematic review registration: PROSPERO-ID CRD42022308833.
Journal Article
Correction to: Cognitive dysfunction and subjective symptoms in patients with arachnoid cyst before and after surgery
2020
Incorrect family name of Åsa Bergendal.
Journal Article