Search Results (91)

Background: Extracranial metastasis (EM) from glioblastoma (GB), IDH-wildtype (WHO CNS 2021 grade 4) is rare and often under-recognized, yet it has immediate implications for staging and management. We report a case series integrating advanced neuroimaging, whole-body imaging, and pathology/biomarkers to characterize imaging–pathology correlates of EM and highlight practical clinical triggers that should prompt systemic evaluation. Case presentation: We report three patients with adult-type, IDH-wildtype GB who developed EM confirmed by cytology/histology and/or concordant multimodality imaging. Brain MRI (1.5T/3T) demonstrated aggressive primary tumors with qualitative elevation of DSC-perfusion and frequent tumor–surface contact (dural, ependymal/leptomeningeal contact). Intratumoral susceptibility signal reached grade 3 where assessed. All patients underwent surgical resection followed by temozolomide-based chemoradiation; two received fotemustine and bevacizumab, and one underwent re-irradiation. EM presented with clinical triggers including severe axial/back pain, palpable cervical masses, and/or cytopenias. Initial EM sites were bone marrow/vertebrae (n = 1) and cervical lymph nodes (n = 2); staging revealed additional osseous disease in both nodal cases and a small pulmonary nodule in one. Nodal and osseous lesions were FDG-avid on 18F-FDG PET/CT. OLIG2-positive cytology confirmed cervical nodal metastases, and bone marrow aspiration with GFAP/OLIG2 positivity confirmed medullary infiltration. All tumors shared a molecular profile of TERT-promoter mutation, ATRX wild-type, TP53 mutation, and MGMT-promoter methylation. Despite attempts at second- and third-line therapies, disease progression was rapid, and all patients succumbed within 8–16 months of diagnosis. Discussion: This series underscores that EM can occur despite MGMT-promoter methylation and supports the concept of heterogeneous metastatic phenotypes in GB. Our cases reinforce that new axial/back pain or hematologic abnormalities may signal osseous or marrow involvement, and necrotic cervical lymphadenopathy in GB patients warrants dedicated imaging and tissue confirmation with glial markers. Integrating brain MRI features (high perfusion, surface contact, susceptibility burden) with FDG-PET/CT and targeted cytology/pathology can expedite diagnosis and inform multidisciplinary care. Conclusions: EM can arise despite MGMT-promoter methylation in IDH-wildtype GBM. Imaging red flags (high perfusion, surface contact, necrotic/FDG-avid cervical nodes) and clinical cues (axial pain, cytopenias, neck masses) should prompt early systemic staging (CT/PET-CT) and targeted tissue confirmation to advance management. Full article

Background/Objectives: Bone metastases are a common complication of breast cancer. In our previous study, we reported that extracellular vesicles released by osteotropic human (MDA-MB-231) and murine (4T1) breast cancer cells disrupt bone homeostasis by enhancing osteoclast differentiation and impairing osteoblast function. Based on these findings, we investigated whether microRNAs contained within tumour-derived EVs could mediate these bone-altering effects. Methods: MDA-MB-231- and 4T1-EVs were tagged with the RNA-specific fluorophore SYTORNA and employed to treat mouse primary bone marrow macrophages (BMMs) and osteoblasts (OBs). We also performed RNAseq on MDA-MB-231- and 4T1-EVs to assess their miRNAs content. Finally, we evaluated the effect of selected miRNA-mimics on OBs, BMMs and HUVEC cells. Results: Fluorescence microscopy demonstrated EV-RNAs shuttling to recipient cells, while RNA sequencing on MDA-MB-231- and 4T1-EVs revealed that, of the top 20 expressed miRNAs, 10 were common. Among them, we first focused on the following four: miR-26a-5p, miR-24-3p, miR-29a-3p, and miR-29b-3p, which were linked to bone biology. We confirmed their presence in MDA-MB-231-/4T1-EVs by qPCR. Then, we evaluated their EV-mediated shuttling to BMMs and OBs using affinity tags. Among all the conditions tested, miR-29a and miR-29b were the best-shuttled miRNAs, with efficiency between 50–100% in both OBs and BMMs, both for MDA-MB-231- and 4T1-EVs. Finally, to test whether miR-29a and miR-29b could have a functional role in bone cells, OBs were transfected with miR-29a and 29b-mimics, discovering that this treatment reduced collagen1α1 and 1α2 mRNA as well as the OBs’ mineralisation ability, while the same miRNA mimics were found to have no effect on osteoclastogenesis or on in vitro angiogenesis. Conclusions: MDA-MB-231- and 4T1-EVs shuttle miRNAs to bone cells, which likely contributes to OBs’ activity impairment. Full article

Background: Breast cancer remains a major health issue, with bone metastases negatively impacting patient outcomes. The biochemical and biological functions of the exon 4-splice isoform (ZNF217-ΔE4) of the oncogenic transcription factor ZNF217 have been poorly investigated. Methods/Results: This study, for the first time, elucidates through advanced live-cell single-molecule tracking microscopy that the C-terminus of ZNF217 influences chromatin engagement and binding stability. ZNF217-ΔE4 retains its ability to be recruited and to promote positive transcriptional activity. CRISPR/Cas9-mediated silencing of the ZNF217 gene in MDA-MB-231 breast cancer cells impairs cell aggressiveness, while reintroduction of the ZNF217-ΔE4 isoform is sufficient to restore increased cell proliferation, migration, invasion, and stemness features. In vivo, ZNF217 ΔE4—although less potent than the wild-type isoform—accelerates the formation of bone marrow micrometastases. A retrospective analysis of primary breast tumors revealed that patients with high ZNF217-ΔE4 mRNA levels had a higher risk of developing bone metastases. Conclusions: Overall, this study identifies ZNF217-ΔE4 as a novel functional isoform that mediates breast cancer cell aggressiveness and bone marrow homing. It also highlights this isoform as a promising biomarker and potential therapeutic target for breast cancers at elevated risk of bone metastasis. Full article

Background/Objectives: The combination of chemotherapy and radiotherapy represents a standard adjuvant treatment for patients with high-risk endometrial cancer. However, limited access to radiotherapy in many healthcare systems frequently results in treatment delays, potentially compromising outcomes. The aim of this study was to evaluate the oncologic outcomes and toxicity profile of an inverted treatment sequence consisting of upfront chemotherapy followed by concurrent chemoradiotherapy. Methods: We conducted a retrospective single-center study including patients with non-metastatic high-risk endometrial cancer. Eligible patients had FIGO stage I grade 3 disease with lymphovascular space invasion, stage II–III disease, or non-endometrioid histology. All patients received four cycles of paclitaxel–carboplatin followed by pelvic radiotherapy with concurrent cisplatin. Survival outcomes, including local recurrence-free survival, disease-free survival, metastasis-free survival, and overall survival, were analyzed using the Kaplan–Meier method and Cox proportional hazards models. Acute hematologic toxicity was graded according to CTCAE v5.0. Bone marrow dose–volume parameters were evaluated, and receiver operating characteristic curve analysis was performed to identify thresholds associated with grade ≥ 2 hematologic toxicity. Results: Fifty-two patients were included, with a median follow-up of 31.4 months. Five-year overall survival and disease-free survival rates were 86.1% and 77.5%, respectively. Ten patients relapsed, with distant metastases observed in all cases and synchronous local recurrence in one. Delays between surgery and radiotherapy of 20 weeks or more, as well as delays exceeding 10 weeks before initiation of chemotherapy, were associated with significantly reduced disease-free survival. Grade ≥ 2 hematologic toxicity was frequent, and neutropenia was associated with inferior overall survival. Bone marrow dose–volume thresholds predictive of hematologic toxicity included V40 Gy < 20–25% and V30 Gy < 40%. Conclusions: A chemotherapy-first adjuvant strategy provides favorable oncologic outcomes and excellent locoregional control in high-risk endometrial cancer when radiotherapy is delayed. However, increased hematologic toxicity highlights the importance of optimized bone marrow sparing. Full article

Background/Objectives: This study aimed to evaluate the prognostic value of ¹⁸F-FDG PET/CT-based secondary lymphoid organ metabolic ratios—spleen/liver (SLR), bone marrow/liver (BLR), and ileocecal region/liver (ILR)—and hematological inflammation markers (neutrophil/lymphocyte ratio [NLR] and systemic immune-inflammation index [SII]) obtained before nivolumab treatment in relation to survival in patients with advanced non-small cell lung cancer (NSCLC). Methods: This retrospective single-center study included 79 advanced NSCLC patients who were treated with nivolumab monotherapy at Marmara University Faculty of Medicine Hospital between 2022 and 2024. Pretreatment SLR, BLR, and ILR ratios were calculated from ¹⁸F-FDG PET/CT examinations; NLR and SII values were obtained from hematological data. Survival outcomes were analyzed using the Kaplan–Meier method, and prognostic factors were assessed using Cox proportional hazards regression analysis. In a subset of patients, an exploratory longitudinal analysis was performed using early follow-up PET/CT to assess follow-up-to-baseline changes in immune-organ metabolic ratios in relation to overall survival. Results: High NLR and SII levels were significantly associated with shorter progression-free survival and overall survival. In contrast, no significant associations were observed between PET/CT-derived metabolic ratios (SLR, BLR, and ILR) and survival. Multivariate analysis identified the presence of liver metastases and a high NLR as independent adverse prognostic factors for overall survival. Conclusions: In this homogeneous real-world cohort treated exclusively with single-agent nivolumab, PET/CT-derived secondary lymphoid organ metabolic ratios showed limited prognostic value at baseline and during early on-treatment assessment. In contrast, hematological inflammation markers, especially high NLR levels, are strong prognostic indicators of survival and may complement established clinical factors in risk stratification. Full article

Bone metastases mark a critical and often terminal phase in cancer progression, where disseminated tumor cells (DTCs) manage to infiltrate and exploit the complex microenvironments of the bone marrow. While most current therapies focus on the well-known late-stage “vicious cycle” of osteolysis, they often overlook the earlier stages, namely, tumor cell colonization and dormancy. During these early phases, cancer cells co-opt hematopoietic stem cell (HSC) niches, using them as sanctuaries for long-term survival. In this review, we bring together emerging insights that highlight a trio of underappreciated cellular players in this metastatic takeover: megakaryocytes, erythroid lineage cells, and perivascular stromal subsets. Far from being passive bystanders, these cells actively shape the metastatic niche. For instance, megakaryocytes and platelets go beyond their role in transport; they orchestrate immune evasion and dormancy through mechanisms such as transforming growth factor-β1 (TGF-β1) signaling and the physical shielding of tumor cells. In parallel, we uncover a distinct “erythroid-immune” axis: here, stress-induced CD71⁺ erythroid progenitors suppress T-cell responses via arginase-mediated nutrient depletion and checkpoint engagement, forming a potent metabolic barrier against immune attack. Furthermore, leptin receptor–positive (LepR⁺) perivascular stromal cells emerge as key structural players. These stromal subsets not only act as anchoring points for DTCs but also maintain them in protective vascular zones via CXCL12 chemokine gradients. Altogether, these findings reveal that the metastatic bone marrow niche is not static; it is a highly dynamic, multi-lineage ecosystem. By mapping these intricate cellular interactions, we argue for a paradigm shift: targeting these early and cooperative crosstalk, whether through glycoprotein-A repetitions predominant (GARP) blockade, metabolic reprogramming, or other niche-disruptive strategies, could unlock new therapeutic avenues and prevent metastatic relapse at its root. Full article

Bone metastases remain a leading cause of morbidity and mortality in patients with advanced breast, prostate, and lung cancers. A striking clinical feature of bone metastasis is the ability of disseminated tumor cells (DTCs) to persist in a dormant state for years or even decades before reawakening to drive overt disease. While the molecular and microenvironmental cues that induce and maintain dormancy have been increasingly studied, the mechanisms governing dormancy escape remain poorly defined yet are critical for preventing relapse. In this review, we synthesize emerging evidence on how the bone microenvironment orchestrates the transition of dormant tumor cells into proliferative lesions. We discuss how osteoclast-mediated bone resorption liberates growth factors such as TGF-β and IGF-1, fueling reactivation; how loss of osteoblast-mediated quiescence signals disrupts the endosteal niche; and how bone marrow adipocytes provide metabolic support through lipid transfer and adipokine secretion. We highlight the role of immune surveillance in maintaining dormancy and how immunosuppressive myeloid populations, regulatory T cells, and inflammatory triggers, such as neutrophil extracellular traps, promote escape. Additional emphasis is placed on extracellular matrix remodeling, mechanotransduction, angiogenic switching, and systemic factors, including aging, hormonal changes, and sympathetic nervous system activation. We also review epigenetic and metabolic reprogramming events within dormant cells that enable reactivation. Finally, we evaluate therapeutic strategies to sustain dormancy or prevent reawakening, including osteoclast-targeted therapies, immune-modulating approaches, and epigenetic or metabolic interventions. By integrating these insights, we identify key knowledge gaps and propose future directions to intercept dormancy escape and delay or prevent metastatic relapse in bone. Full article

The premetastatic niche (PMN) represents a specialized microenvironment established in distant organs before the arrival of metastatic cells. This concept has fundamentally altered our understanding of cancer progression, shifting it from a random event-driven process to an orchestrated one. This review examines the critical role of extracellular proteases in PMN formation, focusing on matrix metalloproteinases (MMPs), serine proteases, and cysteine cathepsins that collectively orchestrate extracellular matrix remodeling, immune modulation, and vascular permeability changes essential for metastatic colonization. Key findings demonstrate that MMP9 and MMP2 facilitate basement membrane degradation and the recruitment of bone marrow-derived cells. At the same time, tissue inhibitor of metalloproteinase-1 (TIMP-1) promotes organ-specific hepatic PMN recruitment through neutrophil recruitment mechanisms. The plasminogen–plasmin system emerges as a master regulator through its broad-spectrum proteolytic activity and ability to activate downstream proteases, with S100A10-mediated plasmin generation providing mechanistic pathways for remote PMN conditioning. Neutrophil elastase and cathepsin G contribute to the degradation of anti-angiogenic proteins, thereby creating pro-metastatic microenvironments. These protease-mediated mechanisms represent the earliest interventional window in metastatic progression, offering therapeutic potential to prevent niche formation rather than treat established metastases. However, significant methodological challenges remain, including the need for organ-specific biomarkers, improved in vivo methods for measuring protease activity, and a better understanding of temporal PMN dynamics across different target organs. Full article

Background: Hypereosinophilia, defined as a peripheral blood eosinophil count greater than 1.5 × 10⁹/L, can arise from allergic, infectious, autoimmune, or malignant conditions. In solid tumors, it is rare and most often linked to mucin-secreting carcinomas, while on extremely rare occasions, it accompanies signet ring cell carcinoma, a highly aggressive form of adenocarcinoma. Case Presentation: A 64-year-old woman presented with dyspnea and hypereosinophilia (2.9 × 10⁹/L). She was admitted with suspected eosinophilic pneumonia, but extensive testing was inconclusive. After bone marrow biopsy, her condition deteriorated; histology revealed metastatic signet ring cell carcinoma. PET/CT showed skeletal metastases without apparent local recurrence, although colonoscopy could not be performed to definitively rule it out. Retrospective review uncovered a 2 mm rectal polyp with signet ring cell carcinoma (SRCC) removed two years earlier. Peripheral eosinophilia progressively increased from 0.16 × 10⁹/L ten months earlier to a peak of 4.29 × 10⁹/L one month prior to admission. She died four weeks after discharge. Conclusions: To the best of our knowledge, this case represents one of the smallest reported primary colorectal SRCC lesions (2 mm) presenting with disseminated disease and paraneoplastic hypereosinophilia as the first diagnostic clue. Monitoring peripheral blood eosinophil counts may provide additional insight into disease activity and prognosis in solid tumors. Full article

Primary spinal osseous tumors are relatively rare, comprising ~5–10% of spinal bone neoplasms, whereas metastases account for the vast majority of spinal lesions. Patients commonly present with insidious back pain, sometimes with a focal mass, and constitutional symptoms are uncommon early in the disease course. As clinical features are often nonspecific and may overlap with degenerative, infectious, and metastatic disease, imaging plays an important role in lesion identification, characterization, and treatment planning. Computed tomography helps to define osseous architecture and matrix characteristics. Magnetic resonance imaging can assess marrow involvement, soft tissue extension, neural compression and intra-canal disease, and tumor vascularity. Together, advanced imaging modalities guide further workup, optimize biopsy planning, inform prognostic assessment and therapeutic decision-making, and anticipate mechanical instability or neural compromise. This narrative pictorial review synthesizes radiographic, CT, and MRI appearances of primary spinal tumors across major histologic lineages (e.g., osteogenic, chondrogenic, notochordal, vascular), illustrated with representative cases. We correlate imaging with clinical presentation to distinguish typical from atypical variants and highlight mimics and pitfalls with implications for diagnostic interpretation and management. Full article

Background/Objectives: Preclinical and clinical evidence supports a chaperone-based vaccination platform for cancer immunotherapy. The objective of this study is to interrogate the next generation of chaperone-based immune modulator, termed Flagrp170, which was constructed by fusing a defined NF-κB-activating microbial sequence with a large stress protein with a superior antigen-holding/presenting property in the setting of antigen-targeted cancer vaccination. Methods: Bone marrow-derived dendritic cells were treated with Flagrp170 protein or an unmodified parental chaperone molecule (i.e., Grp170), followed by an analysis of DC activation and DC-mediated T cell priming using both in vitro and in vivo models. Antitumor vaccine responses in mice receiving tumor antigens (e.g., gp100, Her2/neu) complexed with Flagrp170 or Grp170 were examined through multiple immune assays. The potential use of a Flagrp170-based chaperone vaccine to sensitize tumors to anti-PD-1 therapy was also evaluated. Results: Flagrp170 not only retains the intrinsic ability of the parent chaperone to facilitate antigen cross-presentation, but also acquires a unique capacity to stimulate DCs efficiently through the engagement of TLR5-NF-κB signaling. This chimeric chaperone shows superior activity compared to the unmodified parental molecule, resulting in enhanced DC activation and T cell priming. Vaccination with Flagrp170 complexed to tumor antigens induces a robust T cell response against primary tumors and metastases, a process critically dependent on CD8⁺ DCs. Additionally, the Flagrp170 chaperone vaccine can efficiently generate and expand tumor-reactive T cells. The consequent remodeling of the tumor microenvironment towards a Th1/Tc1 dominant immune phenotype significantly potentiates cancer responsiveness to anti-PD1 therapy. Conclusions: Given the safety and T cell stimulation profiles of the chaperone–antigen complex vaccine already established in our recent clinical trial, this new generation of chaperone cargo, capable of delivering both antigenic targets and pathogen-associated immunoactivating signals simultaneously, represents a promising strategy to potentially improve the low response rates in patients receiving immune checkpoint inhibitors. Full article

Bone metastases continue to be a major cause of morbidity and mortality in patients with advanced cancers, driven by the dynamic remodeling of the bone marrow niche. Traditionally viewed as passive space-fillers, bone marrow adipocytes (BMAs) are now recognized as active regulators of tumor growth, therapeutic resistance, and skeletal pathology. BMAs comprise a significant portion of the adult marrow space, particularly in aging and obesity, and facilitate metastatic colonization through various mechanisms. These include metabolic coupling, where adipocyte-derived fatty acids fuel tumor oxidative phosphorylation; the secretion of adipokines such as leptin and IL-6, which promote epithelial-to-mesenchymal transition, invasion, and immune evasion; regulation of osteoclastogenesis via RANKL expression; and the release of extracellular vesicles that reprogram cancer cell metabolism. Clinical and experimental studies show that BMA expansion correlates with increased tumor burden and poorer outcomes in breast, prostate, lung cancers, and multiple myeloma. Additionally, BMAs actively promote therapeutic resistance through metabolic rewiring and drug sequestration. Experimental models, ranging from in vitro co-cultures to in vivo patient-derived xenografts, demonstrate the complex roles of BMAs and also reveal important translational gaps. Despite promising preclinical approaches such as metabolic inhibitors, PPARγ modulation, adipokine blockade, and lifestyle changes, no therapies directly targeting BMAs have yet reached clinical practice. This review compiles current evidence on the biology of BMAs, their tumor-promoting interactions, and potential therapeutic strategies, while also highlighting unresolved questions about BMA heterogeneity, lipid flux, and immunometabolic crosstalk. By revealing how bone marrow adipocytes actively shape the metastatic niche through metabolic, endocrine, and immunological pathways, this review highlights their potential as novel biomarkers and therapeutic targets for improving the management of bone metastases. Full article

Background/objectives: Despite advancements in early diagnosis and clinical practices guided by standardized care protocols, Merkel cell carcinoma (MCC) is marked by an unfavorable prognosis with a 5-year relative survival rate of 65%, based primarily on data collected prior to the introduction of immunotherapy. Regional nodal metastases affect 40–50% of MCC patients, while approximately 33% experience distant dissemination. Among these, bone and bone marrow metastases are particularly notable, although the characteristics and clinical implications of this metastatic disease in MCC remain poorly understood. Methods: A comprehensive review was conducted using the Medline database (via PubMed) up to January 2025. The search strategy included the string “(Merkel cell carcinoma AND (bone OR marrow))”. Results: A total of 1133 (69.3% male and 30.7% female) patients diagnosed with advanced MCC were collected. The median (IQR) age at diagnosis was 67.5 (12.65) years old. Overall, 201 (20.8%) cases of bone and/or bone marrow metastases were identified and linked to a primary known MCC in 75.7% of cases. Bone metastases (BMs) appear as the third most common metastatic site, following the liver (second) and lymph nodes (first). They show mixed biological and radiological behavior, with a marked preference for the axial skeleton over the appendicular one. Addressing the characteristics of metastatic bone disease, neurological symptoms were the most documented, whereas bone marrow involvement and leukemic spread seemed to be primarily related to immunosuppression. Multimodal treatment strategies, including platinum-based chemotherapy and radiotherapy, were the primary approaches adopted, reflecting therapeutic practices from the pre-immunotherapy era. Conclusions: The pattern of metastatic spread in MCC differs among studies, with the bones resulting as the third most common site of distant spread. Excluding head and neck MCC, which seems to be more regularly associated with liver metastases, the relationship between the primary tumor site and the development of bone or bone marrow metastases appears inconsistent. Overall, BMs mostly correlated with advanced MCC stages and poorer survival outcomes, with a median overall survival (OS) of 8 months (range 12.75–4). The integration of international guidelines, evolving evidence from clinical trials, and the expanding role of immune checkpoint inhibitors (ICIs) will contribute to improving systemic disease control and enhance patient care. Full article

Bone lesions encountered as part of radiology practice can bring diagnostic challenges, both when encountered incidentally or suspected as a primary bone lesion, and in patients at risk of metastases or marrow-based malignancies. Differentiating benign from malignant bone marrow lesions is critical, yet can be challenging due to overlapping imaging characteristics. One key imaging feature that can assist with diagnosis is the presence of fat within the lesion. Fat can be present either macroscopically (i.e., visible on radiographs, computed tomography (CT), and conventional magnetic resonance imaging (MRI)), or microscopically, detected through specialised MRI techniques such as chemical shift imaging (CSI). This comprehensive review explores the diagnostic significance of both macroscopic and microscopic fat in bone lesions and discusses how its presence can point towards benignity. We illustrate the spectrum of fat-containing bone lesions, encompassing both typical and atypical presentations, and provide practical imaging strategies to increase diagnostic accuracy by utilising radiographs, CT, and MRI in characterising these lesions. Specifically, CSI is highlighted as a non-invasive method for evaluating intralesional fat content, to distinguish benign marrow entities from malignant marrow-replacing conditions based on quantifiable signal drop-off. Furthermore, we detail imaging pitfalls with a focus on conditions that can mimic malignancy (such as aggressive haemangiomas) and collision lesions. Through a detailed discussion and illustrative examples, we aim to guide radiologists and clinicians in recognising reassuring imaging features while also identifying scenarios where further investigation may be warranted. Full article

The role of extracellular vesicles has been extensively studied in physiological and pathological conditions, and growing evidence has pinpointed them as key players in tumor progression, regulation of the metastatic niche, and modulation of anti-tumor immune responses. Indeed, a dynamic transfer of extracellular vesicles between cancer cells and immunological or non-immunological cells homing in the tumor microenvironment exists, and the balance between their release by cancer cells and by normal cells determines cancer progression. Here, we focused on the role of extracellular vesicles in the dysregulation of the bone marrow environment in pediatric tumors such as acute leukemias and neuroblastomata, whose poor prognosis is strictly related to the involvement of such anatomical site. Acute leukemias arise from bone marrow progenitors, whereas approximately 50% of neuroblastoma patients have bone marrow metastases at diagnosis. Thus, here, we discuss the mechanisms underlying the bone marrow dysregulation in pediatric acute leukemias and neuroblastomata with particular emphasis on the involvement of extracellular vesicles. Full article