Comprehensive biomarker diagnostics of unfavorable cancer of unknown primary to identify patients eligible for precision medical therapies.

PURPOSE: Current guidelines recommend combination chemotherapy for treatment of patients with unfavorable cancer of unknown primary (CUP). Biomarker-guided targeted therapies may offer additional benefit. Data on the feasibility and effectiveness of comprehensive genomic biomarker profiling of CUP in a standard clinical practice setting are limited. METHODS: This analysis included 156 patients with confirmed unfavorable CUP diagnosis according to ESMO guidelines, who were treated at the West German Cancer Center, Essen, Germany, from 2015 to 2021. Clinical parameters and outcome data were retrieved from the electronic hospital information system. Genomic biomarker analyses were performed in formalin-fixed paraffin-embedded tumor tissue whenever possible using the QIAseq Multimodal-Pancancer-Panel. RESULTS: Non-squamous histologies, high tumor burden, and age above 60 years associated with poor survival outcome. Tissue availability restricted comprehensive biomarker analyses to 50 patients (32%), reflecting a major limitation in the real-world setting. In those patients a total of 24 potentially actionable alterations were identified in 17 patients (34% of profiled patients, 11% of total population). The most prevalent biomarkers were high tumor mutational burden and BRCA-mutations. CONCLUSION: In a real-world setting precision medicine for patients with CUP is severely restricted by tissue availability, and a limited spectrum of actionable alterations. Progress for patients may require emphasizing the need for sufficient biopsies, and prospective exploration of blood-based biomarker profiling.

SUVmax Above 20 in 18F-FDG PET/CT at Initial Diagnostic Workup Associates with Favorable Survival in Patients with Cancer of Unknown Primary.

Cancer of unknown primary (CUP) is a heterogeneous entity with a limited prognosis. Novel prognostic markers are needed for patient stratification in prospective clinical trials exploring innovative therapies. Methods: In CUP patients treated at the West German Cancer Center Essen, the prognostic value of 18F-FDG PET/CT at the initial diagnostic workup was analyzed by comparing overall survival (OS) in patients who underwent 18F-FDG PET/CT with those who did not. Results: Of 154 patients with a CUP diagnosis, 76 underwent 18F-FDG PET/CT at the initial diagnostic workup. The median overall survival (OS) of the full analysis set was 20.0 mo. Within the PET/CT subgroup, an SUVmax above 20 was associated with significantly superior OS (median OS, not reached vs. 32.0 mo; hazard ratio, 0.261; 95% CI, 0.095-0.713; P = 0.009). Conclusion: Our retrospective work shows that an SUVmax above 20 on 18F-FDG PET/CT at the initial diagnostic workup is a favorable prognostic factor in patients with CUP. This finding deserves further prospective studies for validation.

Acute myeloid leukemia-induced remodeling of the human bone marrow niche predicts clinical outcome.

Murine models of myeloid neoplasia show how leukemia infiltration alters the hematopoietic stem cell (HSC) niche to reinforce malignancy at the expense of healthy hematopoiesis. However, little is known about the bone marrow architecture in humans and its impact on clinical outcome. Here, we dissect the bone marrow niche in patients with acute myeloid leukemia (AML) at first diagnosis. We combined immunohistochemical stainings with global gene expression analyses from these AML patients and correlated them with clinical features. Mesenchymal stem and progenitor cells (MSPCs) lost quiescence and significantly expanded in the bone marrow of AML patients. Strikingly, their HSC- and niche-regulating capacities were impaired with significant inhibition of osteogenesis and bone formation in a cell contact-dependent manner through inhibition of cytoplasmic ß-catenin. Assessment of bone metabolism by quantifying peripheral blood osteocalcin levels revealed 30% lower expression in AML patients at first diagnosis than in non-leukemic donors. Furthermore, patients with osteocalcin levels ≤11 ng/mL showed inferior overall survival with a 1-year survival rate of 38.7% whereas patients with higher osteocalcin levels reached a survival rate of 66.8%. These novel insights into the human AML bone marrow microenvironment help translate findings from preclinical models and detect new targets which might pave the way for niche-targeted therapies in AML patients.