Molecular imaging supports the development of multispecific cancer antibodies.

Multispecific antibodies are engineered antibody derivatives that can bind to two or more distinct epitopes or antigens. Unlike mixtures of monospecific antibodies, the binding properties of multispecific antibodies enable two specific molecules to be physically linked, a characteristic with important applications in cancer therapy. The field of multispecific antibodies is highly dynamic and expanding rapidly; to date, 15 multispecific antibodies have been approved for clinical use, of which 11 were approved for oncological indications, and more than 100 new antibodies are currently in clinical development.

Facts and Hopes for PET Imaging-Derived Immunotherapy Biomarkers.

Current immunotherapies have brought major progress in cancer treatments, but not all patients benefit. Therefore, insight into reasons for treatment failure and optimal biomarkers for patient selection are warranted. Current approved biomarkers for cancer immunotherapy do not provide insight into characteristics across tumor lesions in a patient or their heterogeneity.

Monoclonal antibody biosimilars for cancer treatment.

Monoclonal antibodies are important cancer medicines. The European Medicines Agency (EMA) approved 48 and the Food and Drug Administration (FDA) 56 anticancer monoclonal antibody-based therapies. Their high prices burden healthcare systems and hamper global drug access.

Independent transcriptional patterns reveal biological processes associated with disease-free survival in early colorectal cancer.

Background: Bulk transcriptional profiles of early colorectal cancer (CRC) can fail to detect biological processes associated with disease-free survival (DFS) if the transcriptional patterns are subtle and/or obscured by other processes' patterns. Consensus-independent component analysis (c-ICA) can dissect such transcriptomes into statistically independent transcriptional components (TCs), capturing both pronounced and subtle biological processes.

Methods: In this study we (1) integrated transcriptomes (n = 4228) from multiple early CRC studies, (2) performed c-ICA to define the TC landscape within this integrated data set, 3) determined the biological processes captured by these TCs, (4) performed Cox regression to identify DFS-associated TCs, (5) performed random survival forest (RSF) analyses with activity of DFS-associated TCs as classifiers to identify subgroups of patients, and 6) performed a sensitivity analysis to determine the robustness of our results RESULTS: We identify 191 TCs, 43 of which are associated with DFS, revealing transcriptional diversity among DFS-associated biological processes.

Efficacy and Safety of Panitumumab in Patients With RAF/RAS-Wild-Type Glioblastoma: Results From the Drug Rediscovery Protocol.

Background: The prognosis of malignant primary high-grade brain tumors, predominantly glioblastomas, is poor despite intensive multimodality treatment options. In more than 50% of patients with glioblastomas, potentially targetable mutations are present, including rearrangements, altered splicing, and/or focal amplifications of epidermal growth factor receptor (EGFR) by signaling through the RAF/RAS pathway. We studied whether treatment with the clinically available anti-EGFR monoclonal antibody panitumumab provides clinical benefit for patients with RAF/RAS-wild-type (wt) glioblastomas in the Drug Rediscovery Protocol (DRUP).

Phase II study (KAMELEON) of single-agent T-DM1 in patients with HER2-positive advanced urothelial bladder cancer or pancreatic cancer/cholangiocarcinoma.

The antibody-drug conjugate trastuzumab emtansine (T-DM1) is approved for human epidermal growth factor receptor 2 (HER2/ERBB2)-positive breast cancer. We aimed to study tumor HER2 expression and its effects on T-DM1 responses in patients with HER2-positive urothelial bladder cancer (UBC) or pancreatic cancer (PC)/cholangiocarcinoma (CC). In the phase II KAMELEON study (NCT02999672), HER2 status was centrally assessed by immunohistochemistry, with positivity defined as non-focal homogeneous or heterogeneous overexpression of HER2 in ≥30% of stained cells.

Potential, Limitations and Risks of Cannabis-Derived Products in Cancer Treatment.

The application of cannabis products in oncology receives interest, especially from patients. Despite the plethora of research data available, the added value in curative or palliative cancer care and the possible risks involved are insufficiently proven and therefore a matter of debate. We aim to give a recommendation on the position of cannabis products in clinical oncology by assessing recent literature.

Opportunities on the horizon for the management of early colon cancer.

There is a clear unmet need to improve early colon cancer management. This review encompasses the current systemic treatment landscape and summarises novel and pivotal trials. The Immunoscore and circulating tumour DNA (ctDNA) are studied to evaluate which patients should receive no, 3, or 6 months of adjuvant treatment.

Manual Versus Artificial Intelligence-Based Segmentations as a Pre-processing Step in Whole-body PET Dosimetry Calculations.

Purpose: As novel tracers are continuously under development, it is important to obtain reliable radiation dose estimates to optimize the amount of activity that can be administered while keeping radiation burden within acceptable limits. Organ segmentation is required for quantification of specific uptake in organs of interest and whole-body dosimetry but is a time-consuming task which induces high interobserver variability. Therefore, we explored using manual segmentations versus an artificial intelligence (AI)-based automated segmentation tool as a pre-processing step for calculating whole-body effective doses to determine the influence of variability in volumetric whole-organ segmentations on dosimetry.

Molecular imaging to support cancer immunotherapy.

The advent of immune checkpoint inhibitors has reinvigorated the field of immuno-oncology. These monoclonal antibody-based therapies allow the immune system to recognize and eliminate malignant cells. This has resulted in improved survival of patients across several tumor types.

Comparison of [F]DOPA and [Ga]DOTA-TOC as a PET imaging tracer before peptide receptor radionuclide therapy.

Background: In treatment of neuroendocrine neoplasms (NENs), confirmation of somatostatin receptor expression with Ga-DOTA somatostatin analogues is mandatory to determine eligibility for peptide receptor radionuclide therapy (PRRT). [F]DOPA can detect additional lesions compared to [Ga]DOTA-TOC. The aim of this study was to explore differences in tumour detection of both tracers and their relevance for selecting patients for PRRT.

Zr-3,2-HOPO-Mesothelin Antibody PET Imaging Reflects Tumor Uptake of Mesothelin-Targeted Th-Conjugate Therapy in Mice.

The mesothelin (MSLN)-targeted Th conjugate is a novel α-therapy developed to treat MSLN-overexpressing cancers. We radiolabeled the same antibody-chelator conjugate with Zr to evaluate whether PET imaging with Zr-MSLN matches Th-MSLN tumor uptake, biodistribution, and antitumor activity. Serial PET imaging with protein doses of 4, 20, or 40 μg of Zr-MSLN and Zr-control was performed up to 168 h after tracer injection in human tumor-bearing nude mice with high (HT29-MSLN) and low (BxPc3) MSLN expression.

First-line everolimus and cisplatin in patients with advanced extrapulmonary neuroendocrine carcinoma: a nationwide phase 2 single-arm clinical trial.

Background: Extrapulmonary neuroendocrine carcinoma (EP-NEC) are an aggressive subgroup of neuroendocrine neoplasms (NEN). Advanced EP-NEC is generally treated with platinum-based cytotoxic regimens, but progressive disease occurs rapidly, resulting in a poor prognosis. Genetic alterations in the mammalian target for rapamycin (mTOR) pathway have been identified in NEN, providing a rationale for treatment with the mTOR-inhibitor everolimus.

Radiolabeled Monoclonal Antibody Against Colony-Stimulating Factor 1 Receptor Specifically Distributes to the Spleen and Liver in Immunocompetent Mice.

Macrophages can promote tumor development. Preclinically, targeting macrophages by colony-stimulating factor 1 (CSF1)/CSF1 receptor (CSF1R) monoclonal antibodies (mAbs) enhances conventional therapeutics in combination treatments. The physiological distribution and tumor uptake of CSF1R mAbs are unknown.

Patients with Biallelic BRCA1/2 Inactivation Respond to Olaparib Treatment Across Histologic Tumor Types.

Purpose: To assess the efficacy of olaparib, a PARP inhibitor (PARPi) in patients with tumors with mutations, regardless of histologic tumor type.

Patients And Methods: Patients with treatment-refractory mutated cancer were included for treatment with off-label olaparib 300 mg twice daily until disease progression or unacceptable toxicity. In Drug Rediscovery Protocol (DRUP), patients with treatment-refractory solid malignancies receive off-label drugs based on tumor molecular profiles while whole-genome sequencing (WGS) is performed on baseline tumor biopsies.

Perioperative Systemic Therapy vs Cytoreductive Surgery and Hyperthermic Intraperitoneal Chemotherapy Alone for Resectable Colorectal Peritoneal Metastases: A Phase 2 Randomized Clinical Trial.

Importance: To date, no randomized clinical trials have investigated perioperative systemic therapy relative to cytoreductive surgery and hyperthermic intraperitoneal chemotherapy (CRS-HIPEC) alone for resectable colorectal peritoneal metastases (CPM).

Objective: To assess the feasibility and safety of perioperative systemic therapy in patients with resectable CPM and the response of CPM to neoadjuvant treatment.

Design, Setting, And Participants: An open-label, parallel-group phase 2 randomized clinical trial in all 9 Dutch tertiary centers for the surgical treatment of CPM enrolled participants between June 15, 2017, and January 9, 2019.

Mesothelin/CD3 half-life extended bispecific T-cell engager molecule shows specific tumor uptake and distributes to mesothelin and CD3 expressing tissues.

BiTE (bispecific T-cell engager) molecules exert antitumor activity by binding one arm to CD3 on cytotoxic T-cells and the other arm to a tumor-associated antigen. We generated a fully mouse cross-reactive mesothelin (MSLN)-targeted BiTE molecule that is genetically fused to a Fc-domain for half-life extension, and evaluated biodistribution and tumor targeting of a zirconium-89 (Zr)-labeled MSLN HLE BiTE molecule in 4T1 breast cancer bearing syngeneic mice with positron emission tomography (PET). Biodistribution of 50 µg Zr-MLSN HLE BiTE was studied over time by PET imaging in BALB/c mice and revealed uptake in tumor and lymphoid tissues with an elimination half-life of 63.

Patient-Derived Organoid Models of Human Neuroendocrine Carcinoma.

Gastroenteropancreatic neuroendocrine carcinoma (GEP-NEC) is a poorly understood disease with limited treatment options. A better understanding of this disease would greatly benefit from the availability of representative preclinical models. Here, we present the potential of tumor organoids, three-dimensional cultures of tumor cells, to model GEP-NEC.

Comparison of 18F-DOPA Versus 68Ga-DOTATOC as Preferred PET Imaging Tracer in Well-Differentiated Neuroendocrine Neoplasms.

Purpose: The aim of this study was to retrospectively compare 18F-FDOPA versus 68Ga-DOTATOC PET in lesion detection rates and laboratory tumor markers in patients with neuroendocrine neoplasms (NENs).

Patients And Methods: All patients with histologically proven NEN between May 2015 and February 2019 were included who underwent both 18F-DOPA and 68Ga-DOTATOC PET scans within 6 months from each other (mean, 75; median, 38; range, 2-168 days). All patients, except those with pancreatic NEN, received carbidopa before 18F-DOPA PET.

Reconsider radiation exposure from imaging during immune checkpoint inhibitor trials to reduce risk of secondary cancers in long-term survivors?

Immune checkpoint inhibitors (ICI) have improved outcomes for patients with advanced cancers, and results in increasing numbers of long-term survivors. For registration studies, progression-free survival and disease-free survival often serve as primary endpoints. This requires repeated computed tomography (CT) scans for tumour imaging which might lead to major radiation exposure.

The Biodistribution of a CD3 and EpCAM Bispecific T-Cell Engager Is Driven by the CD3 Arm.

Bispecific T-cell engager (BiTE) molecules are designed to engage and activate cytotoxic T cells to kill tumor cells. Little is known about their biodistribution in immunocompetent settings. To explore their pharmacokinetics and the role of the immune cells, BiTE molecules were radiolabeled with the PET isotope Zr and studied in immunocompetent and immunodeficient mouse models.

Compliance and tolerability of short-course radiotherapy followed by preoperative chemotherapy and surgery for high-risk rectal cancer - Results of the international randomized RAPIDO-trial.

Background: Preoperative chemoradiotherapy (CRT) followed by total mesorectal excision is widely accepted as the standard of care for high-risk rectal cancer. Adjuvant chemotherapy is advised in several international guidelines, although the survival benefit remains unclear and compliance is poor. The current multidisciplinary approach has led to major improvements in local control, yet the occurrence of distant metastases has not decreased accordingly.