Parp inhibitors as maintenance treatment in platinum sensitive recurrent ovarian cancer: An updated meta-analysis of randomized clinical trials according to BRCA mutational status Publication date: November 2019 Source: Cancer Treatment Reviews, Volume 80 Author(s): Federica Tomao, Erlisa Bardhi, Anna Di Pinto, Carolina Maria Sassu, Elena Biagioli, Maria Cristina Petrella, Innocenza Palaia, Ludovico Muzii, Nicoletta Colombo, Pierluigi Benedetti Panici Abstract Objective This meta-analysis investigated the effectiveness of PARP inhibitors (PARPis) as maintenance treatment in platinum sensitive recurrent ovarian cancer (ROC), stratifying results based on BRCA mutational status into five different categories: whole population, germ-line BRCA mutated patients, somatic BRCA mutated patients, HRD patients and wild type population. Methods PubMed, Medline, Scopus, EMBASE and clinicaltrials.gov, as well as meeting proceedings were searched for eligible studies that described RCTs testing the efficacy of PARPis as maintenance treatment in platinum sensitive ROC. Data were extracted independently and analysed using RevMan statistical software version 5.3. Primary end-point was progression free survival (PFS). Results The analysis confirmed the positive effect of PARPis in patients with platinum sensitive ROC in case of germinal or somatic BRCA mutations. Specifically, HR for PFS was 0.26, 95% CI 0.21–0.31, p < 0.00001 for the mutation of BRCA gene and 0.24, 95%, CI 0.12–0.48, p < 0.0001 for the somatic alteration. In addition, in the HRD population, studies that analysed the efficacy of PARPis  reported a PFS improvement with HR 0.34, 95% CI 0.26–0.43, p < 0.00001. Finally, our analysis confirms the role of these drugs in prolonging PFS in the whole population with HR 0.36, 95% CI 0.32–0.42, p < 0.00001, although to a lesser extent, with a significant improvement even in wild type cancers with HR 0.49, 95%, CI 0.41–0.59, p < 0.00001). Conclusions PARPis are effective regardless of BRCA mutational status. Future investigations are necessary to explore the use of different PARPis as monotherapy, comparing them among each other in terms of efficacy and toxicity, and exploring their potential re-use.

Evolution of treatment strategies for oligometastatic NSCLC patients – A systematic review of the literature Publication date: November 2019 Source: Cancer Treatment Reviews, Volume 80 Author(s): Daniel H. Schanne, Jana Heitmann, Matthias Guckenberger, Nicolaus H.J. Andratschke Abstract Background The concept of oligometastatic disease (OMD) has expanded the scope of potentially curative therapy for metastatic NSCLC. However, large uncertainties remain regarding its definition and optimal management strategies. We therefore conducted a systematic review to investigate the value of various multimodality treatment concepts. Methods We searched the available literature in Pubmed, Medline and EMBASE using the terms “oligomet*”, “synchron*”, “oligorec*”, “metachr*” “NSCLC”, “lung cancer” and “stage IV” and included studies reporting treatment regimens and outcomes on radically treated patients with either “synchronous”, “metachronous” or “mixed” OMD. Only de-novo diagnosis of OMD was considered. The impact of patient and treatment characteristics on overall survival (OS) and time trends in patterns of care were investigated. Results 54 studies published between 1987 and 2018 were included. Despite a wide range of OMD definitions, 90.1% of patients were treated for a single metastasis. Systemic therapy was used as backbone treatment for most patients. Although surgery was the preferred local treatment in earlier studies, the use of stereotactic radiotherapy increased rapidly after 2011. No OS difference was observed between surgery or radiotherapy as the treatment of primary tumor or metastases, respectively. A time trend towards improved OS after 2011 could be detected. Conclusions While evidence in favor of radical treatment is emerging, most studies remain retrospective and mainly evaluate patients with singular metastases. While surgery, stereotactic radiotherapy and chemotherapy are the cornerstones of current treatment strategies, future clinical trials need to address the high risk of distant metastases by integrating targeted or immunotherapy.

Molecular targeted therapy of glioblastoma Publication date: November 2019 Source: Cancer Treatment Reviews, Volume 80 Author(s): Emilie Le Rhun, Matthias Preusser, Patrick Roth, David A. Reardon, Martin van den Bent, Patrick Wen, Guido Reifenberger, Michael Weller Abstract Glioblastomas are intrinsic brain tumors thought to originate from neuroglial stem or progenitor cells. More than 90% of glioblastomas are isocitrate dehydrogenase (IDH)-wildtype tumors. Incidence increases with age, males are more often affected. Beyond rare instances of genetic predisposition and irradiation exposure, there are no known glioblastoma risk factors. Surgery as safely feasible followed by involved-field radiotherapy plus concomitant and maintenance temozolomide chemotherapy define the standard of care since 2005. Except for prolonged progression-free, but not overall survival afforded by the vascular endothelial growth factor antibody, bevacizumab, no pharmacological intervention has been demonstrated to alter the course of disease. Specifically, targeting cellular pathways frequently altered in glioblastoma, such as the phosphoinositide 3-kinase (PI3K)/protein kinase B (AKT)/mammalian target of rapamycin (mTOR), the p53 and the retinoblastoma (RB) pathways, or epidermal growth factor receptor (EGFR) gene amplification or mutation, have failed to improve outcome, likely because of redundant compensatory mechanisms, insufficient target coverage related in part to the blood brain barrier, or poor tolerability and safety. Yet, uncommon glioblastoma subsets may exhibit specific vulnerabilities amenable to targeted interventions, including, but not limited to: high tumor mutational burden, BRAF mutation, neurotrophic tryrosine receptor kinase (NTRK) or fibroblast growth factor receptor (FGFR) gene fusions, and MET gene amplification or fusions. There is increasing interest in targeting not only the tumor cells, but also the microenvironment, including blood vessels, the monocyte/macrophage/microglia compartment, or T cells. Improved clinical trial designs using pharmacodynamic endpoints in enriched patient populations will be required to develop better treatments for glioblastoma.

Advances and challenges in precision medicine in salivary gland cancer Publication date: November 2019 Source: Cancer Treatment Reviews, Volume 80 Author(s): Gerben Lassche, Wim van Boxtel, Marjolijn J.L. Ligtenberg, Adriana C.H. van Engen-van Grunsven, Carla M.L. van Herpen Abstract Salivary gland cancer (SGC) is a rare malignancy consisting of 22 subtypes with different genetic, histological and clinical characteristics. This rarity and heterogeneity makes systemic treatment of recurrent or metastatic (R/M) disease challenging. Use of chemotherapy is scarcely studied and chemotherapy at best has moderate effects. New therapeutic strategies are therefore warranted, but advances made in SGC are lagging behind on advances made in more common cancers. By unraveling tumor characteristics of SGC, such as genetic alterations and protein expression profiles, therapeutic strategies tailored to the patient’s tumor can be rationalized. This genomic profiling and mapping of immunohistochemical expression profiles is essential in the search for a suitable treatment approach. Thereby, it alleviates the paucity in systemic treatment options and can significantly alter the prognosis of patients with R/M SGC. This review aims to give a comprehensive overview of known genetic alterations and expression profiles amenable for targeted therapy in every histological subtype of SGC. We discuss the remaining knowledge gaps and the implications of these targets for future studies and personalized treatments, thereby aiding clinicians faced with this rare and heterogeneous type of cancer.

Comprehensive intra-individual genomic and transcriptional heterogeneity: Evidence-based Colorectal Cancer Precision Medicine Publication date: November 2019 Source: Cancer Treatment Reviews, Volume 80 Author(s): Ioannis D. Kyrochristos, Dimitrios H. Roukos Abstract Despite advances in translating conventional research into multi-modal treatment for colorectal cancer (CRC), therapeutic resistance and relapse remain unresolved in advanced resectable and, particularly, non-resectable disease. Genome and transcriptome sequencing and editing technologies, coupled with interaction mapping and machine learning, are transforming biomedical research, representing the most rational hope to overcome unmet research and clinical challenges. Rapid progress in both bulk and single-cell next-generation sequencing (NGS) analyses in the identification of primary and metastatic intratumor genomic and transcriptional heterogeneity (ITH) and the detection of circulating cell-free DNA (cfDNA) alterations is providing critical insight into the origins and spatiotemporal evolution of genomic clones responsible for early and late therapeutic resistance and relapse. Moreover, DNA and RNA editing pave new avenues towards the discovery of novel drug targets. Breakthrough combinations of sequencing and editing systems with technologies exploring dynamic interaction networks within pioneering studies could delineate how coding and non-coding mutations perturb regulatory networks and gene expression. This review discusses latest data on genomic and transcriptomic landscapes in time and space, as well as early-phase clinical trials on targeted drug combinations, highlighting the transition from research to clinical Colorectal Cancer Precision Medicine, through non-invasive screening, individualized drug response prediction and development of multiple novel drugs. Future studies exploring the potential to target key transcriptional drivers and regulators will contribute to the next-generation pharmaceutical controllability of multi-layered aberrant transcriptional biocircuits.

Should platinum-based chemotherapy be preferred for germline BReast CAncer genes (BRCA) 1 and 2-mutated pancreatic ductal adenocarcinoma (PDAC) patients? A systematic review and meta-analysis Publication date: November 2019 Source: Cancer Treatment Reviews, Volume 80 Author(s): Taiane F. Rebelatto, Maicon Falavigna, Marta Pozzari, Francesca Spada, Chiara A. Cella, Alice Laffi, Stefania Pellicori, Nicola Fazio Abstract Background Pancreatic ductal adenocarcinoma (PDAC) is one of the most lethal cancers worldwide. Recent studies have shown that 4–20% of patients with PDAC have a germline BReast CAncer (gBRCA) genes 1 and 2 mutation (m). Because homologous recombination is impaired in patients with gBRCAm, some reports suggested that these tumors may be more sensitive to platinum compounds. Therefore, this systematic review and meta-analysis focused on benefit of patients with gBRCAm receiving a platinum-based chemotherapy (PtCh) compared with those treated with a non-platinum-based chemotherapy (NPtCh). Material and methods The following electronic databases were searched from inception to May 12, 2018: PubMed (MEDLINE), EMBASE, and Cochrane Library. Abstracts from conferences were also reviewed for inclusion. Cohort, case-control and randomized studies of patients with PDAC and gBRCAm were eligible for inclusion if they provided data to compare patients receiving PtCh vs NPtCh. The primary endpoint was overall survival (OS) in the PtCh group vs the NPtCh group in patients with clinical stage III (locally advanced) or IV (metastatic) (CS III-IV) PDAC. Results Of 112 studies identified, 6 were included (total of 108 patients); of these, 4 provided sufficient data for meta-analysis. Half of the patients were males, with a mean age ranging from 58 to 63 years. The OS in the 85 patients with CS III-IV PDAC was higher in the PtCh group (23.7 vs 12.2 months; mean difference of 10.21 months, 95% confidence interval [CI] 5.05–15.37; P < 0.001; very low quality of evidence). PtCh was associated with a lower mortality (62.3 vs 87.5%; relative risk of 0.80, 95%CI 0.66–0.97; P = 0.021; very low quality of evidence). Conclusion Our study confirmed the hypothesis that patients with CS III-IV gBRCAm preferably benefit from a PtCh compared with NPtCh. However the very low quality of evidence should induce to be careful about the risk of potential biases. The generated hypothesis should be prospectively investigated in homogenous clinical settings.

RET Fusions in Solid Tumors Publication date: Available online 30 October 2019 Source: Cancer Treatment Reviews Author(s): Andrew Y. Li, Michael G. McCusker, Alessandro Russo, Katherine A. Scilla, Allison Gittens, Katherine Arensmeyer, Ranee Mehra, Vincenzo Adamo, Christian Rolfo Abstract The RET proto-oncogene has been well-studied. RET is involved in many different physiological and developmental functions. When altered, RET mutations influence disease in a variety of organ systems from Hirschsprung’s disease and multiple endocrine neoplasia 2 (MEN2) to papillary thyroid carcinoma (PTC) and non-small cell lung cancer (NSCLC). Changes in RET expression have been discovered in 30-70% of invasive breast cancers and 50-60% of pancreatic ductal adenocarcinomas in addition to colorectal adenocarcinoma, melanoma, small cell lung cancer, neuroblastoma, and small intestine neuroendocrine tumors. RET mutations have been associated with tumor proliferation, invasion, and migration. RET fusions or rearrangements are somatic juxtapositions of 5’ sequences from other genes with 3’ RET sequences encoding tyrosine kinase. RET rearrangements occur in approximately 2.5-73% of sporadic PTC and 1-3% of NSCLC patients. The most common RET fusions are CDCC6-RET and NCOA4-RET in PTC and KIF5B-RET in NSCLC. Tyrosine kinase inhibitors are drugs that target kinases such as RET in RET-driven (RET-mutation or RET-fusion-positive) disease. Multikinase inhibitors (MKI) target various kinases and other receptors. Several MKIs are FDA-approved for cancer therapy (sunitinib, sorafenib, vandetanib, cabozantinib, regorafenib, ponatinib, lenvatinib, alectinib) and non-oncologic disease (nintedanib). Selective RET inhibitor drugs LOXO-292 (selpercatinib) and BLU-667 (pralsetinib) are also undergoing phase I/II and I clinical trials, respectively, with preliminary results demonstrating partial response and low incidence of serious adverse events. RET fusions provide a viable therapeutic target for oncologic treatment, and further study is warranted into the prevalence and pathogenesis of RET fusions as well as development of current and new tyrosine kinase inhibitors.

Molecular insight of regorafenib treatment for colorectal cancer Publication date: Available online 28 October 2019 Source: Cancer Treatment Reviews Author(s): Hiroyuki Arai, Francesca Battaglin, Jingyuan Wang, Jae Ho Lo, Shivani Soni, Wu Zhang, Heinz-Josef Lenz Abstract Regorafenib is a multi-targeting kinase inhibitor approved for the treatment of metastatic colorectal cancer patients in refractory to standard chemotherapy. Similarly to sorafenib, this agent was originally developed as a RAF1 inhibitor. However, the kinase inhibitory profile is distinct from sorafenib. A broad-spectrum of kinase inhibition induces wide-range drug sensitivity, irrespective of mutation status of major oncogenes. This agent’s main therapeutic effects are anti-angiogenesis and the remodeling of tumor microenvironment through several mechanisms of action. The dual blockade of VEGF receptors and TIE2 can lead to both additive anti-angiogenesis effects and the suggestive unique regulation of vessel stability. Additionally, it inhibits molecular escape pathways to VEGF inhibition (e.g., FGF, PIGF, and PDGF signaling), enabling its continuous antiangiogenic effect even in tumors resistant to VEGF inhibitors. Furthermore, regorafenib has the important effect of enhancing anti-tumor immunity via macrophage modulation. Based on this concept, clinical trials have been recently launched for the development of a combination strategy with immune checkpoint inhibitors. Contrary to regorafenib induced clinical benefits and advances in the novel strategy, currently no predictive biomarkers have been identified. In the present review, we revisit and summarize regorafenib’s unique mechanisms of action. The review could highlight molecular insights and provide some perspective for the search of predictive biomarkers used in metastatic colorectal cancer patients treated with regorafenib.

Trametinib in the Treatment of Multiple Malignancies Harboring MEK1 Mutations Publication date: Available online 14 October 2019 Source: Cancer Treatment Reviews Author(s): Tong Lian, Changying Li, Haitao Wang Abstract The aberrant activation of RAS-derived mitogen-activated protein kinase (MAPK) signaling pathway plays a prominent role in tumorigenesis of an array of malignancies. The reasons are usually the upstream activated mutations including mitogen-activated protein kinase kinase 1/2 (MEK1/2). As oncogenic mutations, MEK1 mutations have been observed in a variety of malignancies including melanoma, histiocytic neoplasms, colorectal cancer and lung cancer. Presently, the use of trametinib, a highly selective MEK1/2 inhibitor, was limited to BRAF mutations, according to the approvals of FDA. Therefore, we consider that this is a question worth studying that whether malignancies with MEK1 mutations are sensitive to the treatment of trametinib. This review discussed the function of MEK1 mutations, retrieved the frequency and distribution of MEK1 mutations in various malignancies, and reviewed the basic experiments and clinical case reports on trametinib in the treatment of cell lines or patients with MEK1 mutations. Most studies have demonstrated that trametinib was effective to cells or tumor patients harboring MEK1 mutations, which suggest that the MEK1 mutations might be potential indications of trametinib therapy. In addition, it was also reported that resistance was observed in the treatment of trametinib, suggesting that different MEK1 mutations may have different response to trametinib, and further studies are necessary to distinguish that which MEK1 mutations are appropriate for the treatment with trametinib and which are not.

“Should we favour the use of 5x5 preoperative radiation in rectal cancer” Publication date: Available online 14 October 2019 Source: Cancer Treatment Reviews Author(s): Clare Kane, Rob Glynne-Jones Abstract The management of patients with “locally advanced rectal cancer” (LARC) is evolving from the original aim of reducing local recurrence. Current practice recognises the importance of surgical technique, high-quality preoperative imaging, and integration of neoadjuvant systemic chemotherapy. Contemporary protocols focus on improving survival and avoiding radical surgery with organ preservation strategies. Both short course preoperative radiotherapy (SCPRT) with immediate surgery and long-course chemoradiation (LCCRT) are standard neoadjuvant strategies, both demonstrating similar efficacy in preventing local recurrence, distant metastases and improving disease-free survival (DFS). SCPRT is highly cost-effective with high compliance rates, hence is gaining traction in Europe and East Asia, partly because of inherent flexibility in timing and the ability to add neoadjuvant systemic chemotherapy in as there is a delay to surgery. SCPRT is currently not being exploited to its full extent –particularly in the USA where uptake is approximately 1% of neoadjuvant treatments for rectal cancer. We analyse the use of induction, concurrent and consolidation chemotherapy with SCPRT in a total neoadjuvant therapy (TNT) approach.