Publications by authors named "Samuel Roberts-Thomson"

Background: High-grade gliomas (HGGs) are aggressive primary brain cancers with poor response to standard regimens, driven by immense heterogeneity. In isocitrate dehydrogenase () wild-type HGG (glioblastoma, GBM), increased intratumoral heterogeneity is associated with more aggressive disease.

Methods: Spatial technologies can dissect complex heterogeneity within the tumor ecosystem by preserving cellular organization .

View Article and Find Full Text PDF

The classification of diffuse gliomas has undergone substantial changes over the last decade, starting with the 2016 World Health Organisation (WHO) classification, which introduced the importance of molecular markers for glioma diagnosis, in particular, isocitrate dehydrogenase (IDH) status and 1p/19-codeletion. This has spurred research into the correlation of imaging features with the key molecular markers, known as "radiogenomics" or "imaging genomics". Radiogenomics has a variety of possible benefits, including supplementing immunohistochemistry to refine the histological diagnosis and overcoming some of the limitations of the histological assessment.

View Article and Find Full Text PDF

Primary follicular lymphoma of the prostate is rare. This case report and literature review literature describes a 74-year old male patient who presented with worsening urinary symptoms, and imaging showing prostatomegaly compressing and displacing the rectum. He ultimately underwent a Millen retropubic prostatectomy for a prostate of 692 cc.

View Article and Find Full Text PDF

Background: Spinal bronchogenic cysts are rare nonneoplastic congenital variants of neurenteric cysts. The natural history and surgical management of these lesions are poorly understood.

Observations: A 25-year-old male presented with progressive back pain and bilateral lower limb sciatica of 6 months' duration.

View Article and Find Full Text PDF

The main barrier to a cure for HIV is the persistence of long-lived and proliferating latently infected CD4 T-cells despite antiretroviral therapy (ART). Latency is well characterized in multiple CD4 T-cell subsets, however, the contribution of regulatory T-cells (Tregs) expressing FoxP3 as well as immune checkpoints (ICs) PD-1 and CTLA-4 as targets for productive and latent HIV infection in people living with HIV on suppressive ART is less well defined. We used multiplex detection of HIV DNA and RNA with immunohistochemistry (mIHC) on formalin-fixed paraffin embedded (FFPE) cells to simultaneously detect HIV RNA and DNA and cellular markers.

View Article and Find Full Text PDF

IDH-wild type (wt) glioblastoma (GB) accounts for approximately 90% of all GB and has a poor outcome. Surgery and adjuvant therapy with temozolomide and radiotherapy is the main therapeutic approach. Unfortunately, after relapse and progression, which occurs in most cases, there are very limited therapeutic options available.

View Article and Find Full Text PDF

SP142 programmed cell death ligand 1 (PD-L1) status predicts response to atezolizumab in triple-negative breast carcinoma (TNBC). Prevalence of VENTANA PD-L1 (SP142) Assay positivity, concordance with the VENTANA PD-L1 (SP263) Assay and Dako PD-L1 IHC 22C3 pharmDx assay, and association with clinicopathologic features were assessed in 447 TNBCs. SP142 PD-L1 intraobserver and interobserver agreement was investigated in a subset of 60 TNBCs, with scores enriched around the 1% cutoff.

View Article and Find Full Text PDF

Tuberous sclerosis complex (TSC) is a multisystem autosomal dominant hamartoma syndrome caused by mutations in TSC1 or TSC2 genes, leading to upregulation of cell growth signalling pathways. Subependymal giant cell astrocytomas (SEGAs) are seen almost exclusively in TSC patients. We report a 'solitary SEGA' in an adult patient, with confirmed deletion of the entire TSC2 gene on tumour tissue DNA, in the absence of detectable constitutional mutation or clinical manifestations of TSC.

View Article and Find Full Text PDF

We present a case of orbital giant cell myositis (OGCM), presenting with bilateral subacute progressive ophthalmoplegia and optic nerve dysfunction. An early extraocular muscle biopsy confirmed the diagnosis and guided appropriate management. Comprehensive investigation excluded any underlying systemic disease, including myocarditis.

View Article and Find Full Text PDF

Somatic GNAS and USP8 mutations have been implicated in sporadic somatotrophinomas and corticotrophinomas, respectively. However, no genes are known to be recurrently mutated in sporadic prolactinomas. The prevalence of copy number variants (CNV), which is emerging as a mechanism of tumorigenesis in sporadic pituitary adenomas in general, is also unclear in prolactinomas.

View Article and Find Full Text PDF

Merkel cell carcinoma is a rare neuroendocrine tumor of subspecialized dermal mechanoreceptors, associated with immunosuppression. The usual ophthalmic presentation is an eyelid lesion. The authors present a case of biopsy-proven orbital metastatic Merkel cell carcinoma in the absence of any eyelid lesion, in an immunosuppressed patient with a history of multiple cancers.

View Article and Find Full Text PDF