We investigated the intra-patient heterogeneity of driver gene mutations among colorectal liver metastases by sequencing 479 tumor samples from 106 patients. A near-perfect intra-patient concordance was found in the mutation status of the primary tumor and multiple metastatic lesions of KRAS/NRAS/BRAF and PIK3CA when high-sensitivity methods were applied. Mutations in KRAS alone and KRAS/NRAS/BRAF combined had a negative prognostic impact after liver resection. Background: The prevalence and clinical implications of genetic heterogeneity in patients with multiple colorectal liver metastases remain largely unknown. In a prospective series of patients undergoing resection of colorectal liver metastases, the aim was to investigate the inter-metastatic and primary-to-metastatic heterogeneity of mutations in KRAS, NRAS, BRAF, and PIK3CA and their prognostic impact. Patients and Methods: We analyzed the mutation status among 372 liver metastases and 78 primary tumors from 106 patients by methods used in clinical routine testing, by Sanger sequencing, by next-generation sequencing (NGS), and/or by droplet digital polymerase chain reaction. The 3-year cancer-specific survival (CSS) was analyzed using the Kaplan-Meier method. Results: Although Sanger sequencing indicated inter-metastatic mutation heterogeneity in 14 of 97 patients (14%), almost all cases were refuted by high-sensitive NGS. Also, heterogeneity among metastatic deposits was concluded only for PIK3CA in 2 patients. Similarly, primary-to-metastatic heterogeneity was indicated in 8 of 78 patients (10%) using Sanger sequencing but for only 2 patients after NGS, showing the emergence of 1 KRAS and 1 PIK3CA mutation in the metastatic lesions. KRAS mutations were present in 53 of 106 patients (50%) and were associated with poorer 3-year CSS after liver resection (37% vs. 61% for KRAS wild-type; P ¼ .004). Poor prognostic associations were found also for the combination of KRAS/NRAS/BRAF mutations compared with triple wild-type (P ¼ .002). Conclusion: Intrapatient mutation heterogeneity was virtually undetected, both between the primary tumor and the liver metastases and among the metastatic deposits. KRAS mutations separately, and KRAS/NRAS/BRAF mutations combined, were associated with poor patient survival after partial liver resection.

a b s t r a c tIntroduction: Surgery combined with perioperative chemotherapy has become standard of care in patients with resectable colorectal liver metastases. However, poor outcome is expected for a significant subgroup. The clinical implications of inter-metastatic heterogeneity remain largely unknown. In a prospective, population-based series of patients undergoing resection of multiple colorectal liver metastases, the aim was to investigate the prevalence and prognostic impact of heterogeneous response to neoadjuvant chemotherapy. Materials and Methods: Radiological response to treatment was evaluated in a lesion-specific manner in 2e5 metastases per patient. Change of lesion diameter was evaluated and response/progression was classified according to three different size thresholds; 3, 4 and 5 mm. A heterogeneous response was defined as progression and response of different metastases in the same patient. Results: In total, 142 patients with 585 liver metastases were examined with the same radiological method (MRI or CT) before and after neoadjuvant treatment. Heterogeneous response to treatment was seen in 16 patients (11%) using the 3 mm size change threshold, and this group had a 5-year cancerspecific survival of 19% compared to 49% for patients with response in all lesions (p ¼ 0.003). Cut-off values of 4e5 mm were less sensitive for detecting a heterogeneous response, but the survival difference was similar and significant. Conclusion: A subgroup of patients with multiple colorectal liver metastases had heterogeneous radiological response to neoadjuvant chemotherapy and poor prognosis. The evaluation of response pattern is easy to perform, feasible in clinical practice and, if validated, a promising biomarker for treatment decisions.

Background and Goals: Multiple sclerosis (MS) is a central nervous system inflammatory disease where magnetic resonance imaging (MRI) is an important tool for diagnosis and disease monitoring. Quantitative measurements of lesion volume, lesion count, distribution of lesions, and brain atrophy have a potentially significant value for evaluating disease progression. We hypothesize that utilizing software designed for evaluating MRI data in MS will provide more accurate and detailed analyses compared to the visual neuro-radiological evaluation.Methods: A group of 56 MS patients (mean age 35 years, 70% females and 96% relapsing-remitting MS) was examined with brain MRI one and 5 years after diagnosis. The T1 and FLAIR brain MRI sequences for all patients were analyzed using the LesionQuant (LQ) software. These data were compared with data from structured visual evaluations of the MRI scans performed by neuro-radiologists, including assessments of atrophy, and lesion count. The data from LQ were also compared with data from other validated research methods for brain segmentation, including assessments of whole brain volume and lesion volume. Correlations with clinical tests like the timed 25-foot walk test (T25FT) were performed to explore additional value of LQ analyses.Results: Lesion count assessments by LQ and by the neuro-radiologist were significantly correlated one year (cor = 0.92, p = 2.2 × 10−16) and 5 years (cor = 0.84, p = 2.7 × 10−16) after diagnosis. Analyzes of the intra- and interrater variability also correlated significantly (cor = 0.96, p < 0.001, cor = 0.97, p < 0.001). Significant positive correlation was found between lesion volume measured by LQ and by the software Cascade (cor = 0.7, p < 0.001. LQ detected a reduction in whole brain percentile >10 in 10 patients across the time-points, whereas the neuro-radiologist assessment identified six of these. The neuro-radiologist additionally identified five patients with increased atrophy in the follow-up period, all of them displayed decreasing low whole brain percentiles (median 11, range 8–28) in the LQ analysis. Significant positive correlation was identified between lesion volume measured by LQ and test performance on the T25FT both at 1 and 5 years after diagnosis.Conclusion: For the number of MS lesions at both time-points, we demonstrated strong correlations between the assessments done by LQ and the neuro-radiologist. Lesion volume evaluated with LQ correlated with T25FT performance. LQ-analyses classified more patients to have brain atrophy than the visual neuro-radiological evaluation. In conclusion, LQ seems like a promising supplement to the evaluation performed by neuro-radiologists, providing an automated tool for evaluating lesions in MS patients and also detecting early signs of atrophy in both a longitudinal and cross-sectional setting.

Introduction. Takayasu arteritis is a rare disease affecting the aorta and its main branches, causing arterial claudication and end-organ ischemia, including stroke. The etiology is unknown but is believed to be autoimmune. An association between Takayasu arteritis and tuberculosis has been suggested, but the possible relation is unclear. Case Presentation. A 15-year-old Somali boy was diagnosed with latent tuberculosis. He had a lesion in the right lung, and both the tuberculin skin test by the Mantoux method and Quantiferon GOLD test turned out positive. After he suffered a cerebral infarct in the right hemisphere, childhood Takayasu arteritis was diagnosed. The diagnosis was based on diagnostic imaging showing a high-grade stenosis of the origin of the right common carotid artery, an occluded common carotid artery on the left side, a circumferential thickening of the vessel walls in the right and left common carotid artery, and laboratory findings with elevated C-reactive protein. Conclusion. Takayasu arteritis is an uncommon cause of stroke. It should however be kept in mind as a cause of cerebrovascular disease, especially in the young.

Background and goals: Multiple sclerosis (MS) is a central nervous system inflammatory disease where magnetic resonance imaging (MRI) is an important tool for diagnosis and disease monitoring. Quantitative measurements of lesion volume, lesion count, distribution of lesions and brain atrophy have a potentially significant value for evaluating disease progression. We hypothesize that utilizing software designed for evaluating MRI data in MS will provide more accurate and detailed analyses compared to the visual neuro-radiological evaluation. Methods: A group of 56 MS patients (mean age 35 years, 70% females and 96% relapsing-remitting MS) was examined with brain MRI one and five years after diagnosis. The T1 and FLAIR brain MRI sequences for all patients were analysed using the LesionQuant(LQ) software. These data were compared with data from structured visual evaluations of the MRI scans performed by a neuro-radiologist, including assessments of atrophy and lesion count. Correlations with clinical tests like the timed 25-foot walk test (T25FT) were performed to explore additional value of LQ analyses. Results: Lesion count assessments by LQ and by the neuro-radiologist were significantly correlated one year (cor=0.92, p=2.2x10-16) and five years (cor=0.84, p=2.7x10-16) after diagnosis. LQ detected a reduction in whole brain percentile >10 in 10 patients across the time-points, whereas the neuro-radiologist assessment identified six of these. The neuro-radiologist additionally identified five patients with increased atrophy in the follow-up period, all of them displayed decreasing low whole brain percentiles (median 11, range 8-28) in the LQ analysis. Significant positive correlation was identified between lesion volume measured by LQ and test performance on the T25FT both at one year and five years after diagnosis. Conclusion: For the number of MS lesions at both time-points, we demonstrated strong correlations between the assessments done by LQ and the neuro-radiologist. Lesion volume evaluated with LQ correlated with T25FT performance. LQ-analyses were more sensitive in capturing brain atrophy than the visual neuro-radiological evaluation. In conclusion, LQ seems like a promising supplement to the evaluation performed by neuro-radiologists, providing an automated tool for evaluating lesions and brain volume in MS patients in both a longitudinal and cross-sectional setting.