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Background: Characterization of circulating tumor DNA (ctDNA) has been integrated into clinical practice. Although labs have standardized validation procedures to develop single locus tests, the efficacy of on-site plasma-based next-generation sequencing (NGS) assays still needs to be proved., Materials and Methods: In this retrospective study, we profiled DNA from matched tissue and plasma samples from 75 patients with cancer. We applied an NGS test that detects clinically relevant alterations in 33 genes and microsatellite instability (MSI) to analyze plasma cell-free DNA (cfDNA)., Results: The concordance between alterations detected in both tissue and plasma samples was higher in patients with metastatic disease. The NGS test detected 77% of sequence alterations, amplifications, and fusions that were found in metastatic samples compared with 45% of those alterations found in the primary tumor samples (p = .00005). There was 87% agreement on MSI status between the NGS test and tumor tissue results. In three patients, MSI-high ctDNA correlated with response to immunotherapy. In addition, the NGS test revealed an FGFR2 amplification that was not detected in tumor tissue from a patient with metastatic gastric cancer, emphasizing the importance of profiling plasma samples in patients with advanced cancer., Conclusion: Our validation experience of a plasma-based NGS assay advances current knowledge about translating cfDNA testing into clinical practice and supports the application of plasma assays in the management of oncology patients with metastatic disease. With an in-house method that minimizes the need for invasive procedures, on-site cfDNA testing supplements tissue biopsy to guide precision therapy and is entitled to become a routine practice., Implications for Practice: This study proposes a solution for decentralized liquid biopsy testing based on validation of a next-generation sequencing (NGS) test that detects four classes of genomic alterations in blood: sequence mutations (single nucleotide substitutions or insertions and deletions), fusions, amplifications, and microsatellite instability (MSI). Although there are reference labs that perform single-site comprehensive liquid biopsy testing, the targeted assay this study validated can be established locally in any lab with capacity to offer clinical molecular pathology assays. To the authors' knowledge, this is the first report that validates evaluating an on-site plasma-based NGS test that detects the MSI status along with common sequence alterations encountered in solid tumors., (© 2021 AlphaMed Press.)

Lessons Learned: Hyperfractionation of lutetium-177 ( 177 Lu)-J591 for patients with metastatic castration-resistant prostate cancer did not appear to have any additional advantage over the single dose 177 Lu-J591 or fractionated two-dose 177 Lu-J591 therapy. Definite conclusions were challenging because of the small sample size of this study, and so further studies are needed to evaluate the viability of the hypothesis. On the basis of available data, a registration study of 177 Lu-J591 (also known as TLX591) is planned and will use the two-dose fractionation schedule (Telix Pharma Q3 2019 update https://telixpharma.com/news-media/)., Background: Phase I and II single-dose studies of lutetium-177 ( 177 Lu)-J591, a radio-labeled antibody binding prostate-specific membrane antigen (PSMA), demonstrated safety and efficacy with dose response. Modest dose fractionation of 177 Lu-J591 (2 doses) has less myelosuppression per similar cumulative dose, allowing higher doses to be administered safely. We hypothesized that additional dose fractionation would allow a higher cumulative dose, potentially with less toxicity and more efficacy., Methods: Men with progressive metastatic castration-resistant prostate cancer and adequate organ function were enrolled. 177 Lu-J591 was administered at 25 mCi/m 2 every 2 weeks until the emergence of related grade 2 toxicity. 177 Lu-J591 imaging was performed and circulating tumor cell (CTC) counts were measured before and after treatment along with standard monitoring., Results: Six subjects in a single cohort, with a median age of 68.6 years, were enrolled. Patients received three to six doses (cumulative 75-150 mCi/m 2 ). Two (33%) patients had >30% prostate-specific antigen (PSA) decline and three (50%) had CTC count decline. Two (33%) experienced grade (Gr) 4 neutropenia (without fever), three (50%) had Gr 4 thrombocytopenia (without hemorrhage), and two (33%) required platelet transfusions. Following hematological improvement, two patients developed worsening cytopenia during prostate cancer progression; bone marrow biopsies revealed infiltrative tumor replacing normal marrow elements without myelodysplasia. Targeting of known disease sites was seen on planar imaging in all., Conclusion: Hyperfractionation of 177 Lu-J591 is feasible but does not seem to have significant advantages over the two-dose fractionation regimen., (© AlphaMed Press; the data published online to support this summary are the property of the authors.)

Lessons Learned: Our results highlight additional toxicities of dual PI3K/mTOR inhibition in the clinical setting that were unforeseen from preclinical models.Because of toxicity and lack of efficacy, BEZ235 should not be further developed in the current formulation for patients with renal cell carcinoma., Background: Allosteric inhibitors of the mammalian target of rapamycin complex 1 (mTORC1) are approved for advanced renal cell carcinoma (RCC). Preclinical models have suggested that dual inhibition of phosphatidylinositol 3-kinase (PI3K) and mTOR kinase may establish superior anticancer effect. We aimed to establish safety for BEZ235, a potent inhibitor of both PI3K and mTOR, in advanced RCC., Methods: Patients with advanced RCC who had previously failed standard therapy received escalating doses of BEZ235 in sachet formulation twice daily until progression or unacceptable toxicity. Primary endpoints were to identify the maximally tolerated dose (MTD) and to determine the recommended dose for the phase II study., Results: The study was terminated early because of high incidence of dose-limiting toxicities (DLTs) across all dose levels tested. Ten patients were treated with BEZ235-six with clear cell and four with non-clear cell subtypes. Five of these patients suffered DLTs: 2 of 2 patients in the original 400 mg b.i.d. cohort, 1 of 6 in the 200 mg b.i.d. cohort, and 2 of 2 in the 300 mg b.i.d., Cohort: DLTs included fatigue, rash, nausea and vomiting, diarrhea, mucositis, anorexia, and dysgeusia. Five patients were evaluable for response: Two had stable disease as best response, and three had progressive disease., Conclusion: BEZ235 twice daily resulted in significant toxicity without objective responses; further development of this compound will not be pursued in this disease., (©AlphaMed Press; the data published online to support this summary is the property of the authors.)

In the U.S. and Europe, clinical practice guidelines for metastatic renal cell carcinoma have undergone several revisions as a result of the introduction of molecular-targeted therapies. Recently, the National Comprehensive Cancer Network (NCCN) and the European Association of Urology (EAU) published updated guidelines to reflect these new treatment approaches that provide greater efficacy and better tolerability than the previous standard of care, cytokine therapy with interleukin-2 or interferon-α. Recommendations are classified by line of therapy, Memorial Sloan-Kettering Cancer Center risk level for survival, and level of evidence. Although many similarities exist, levels of evidence between the NCCN and EAU guidelines have differing designations and definitions, and timing of updates varies. New research developments, such as identification of effective combinations of targeted agents, optimal regimens for sequential therapy, newly designed targeted agents, benefits in special populations, and identification of additional prognostic factors and biomarkers, will prompt continued updates and refinements of today's clinical practice guidelines, with the goal of providing physicians with the most up-to-date clinical consensus upon which to base treatment decisions. Because clinical trial populations may not represent real-life patient populations, recommendations should serve only as a guide and must be tailored to the needs of each patient.