Dual targeting of FGFR3 and ERBB3 enhances the efficacy of FGFR inhibitors in FGFR3 fusion-driven bladder cancer.

BACKGROUND: Mutations and fusions in Fibroblast Growth Factor Receptor 3 (FGFR3) occur in 10-20% of metastatic urothelial carcinomas and confer sensitivity to FGFR inhibitors. However, responses to these agents are often short-lived due to the development of acquired resistance. The objective of this study was to identify mechanisms of resistance to FGFR inhibitors in two previously uncharacterised bladder cancer cell lines harbouring FGFR3 fusions and assess rational combination therapies to enhance sensitivity to these agents. METHODS: Acquired resistance to FGFR inhibitors was generated in two FGFR3 fusion harbouring cell lines, SW780 (FGFR3-BAIAP2L1 fusion) and RT4 (FGFR3-TACC3 fusion), by long-term exposure to the FGFR inhibitor BGJ398. Changes in levels of receptor tyrosine kinases were assessed by phospho-RTK arrays and immunoblotting. Changes in cell viability and proliferation were assessed by the Cell-Titre Glo assay and by propidium iodide staining and FACS analysis. RESULTS: Long term treatment of FGFR3-fusion harbouring SW780 and RT4 bladder cancer cell lines with the FGFR inhibitor BGJ398 resulted in the establishment of resistant clones. These clones were cross-resistant to the clinically approved FGFR inhibitor erdafitinib and the covalently binding irreversible FGFR inhibitor TAS-120, but remained sensitive to the MEK inhibitor trametinib, indicating resistance is mediated by alternate activation of MAPK signalling. The FGFR inhibitor-resistant SW780 and RT4 lines displayed increased expression of pERBB3, and strikingly, combination treatment with an FGFR inhibitor and the ATP-competitive pan-ERBB inhibitor AZD8931 overcame this resistance. Notably, rapid induction of pERBB3 and reactivation of pERK also occurred in parental FGFR3 fusion-driven lines within 24 h of FGFR inhibitor treatment, and combination treatment with an FGFR inhibitor and AZD8931 delayed the reactivation of pERBB3 and pERK and synergistically inhibited cell proliferation. CONCLUSIONS: We demonstrate that increased expression of pERBB3 is a key mechanism of adaptive resistance to FGFR inhibitors in FGFR3-fusion driven bladder cancers, and that this also occurs rapidly following FGFR inhibitor treatment. Our findings demonstrate that resistance can be overcome by combination treatment with a pan-ERBB inhibitor and suggest that upfront combination treatment with FGFR and pan-ERBB inhibitors warrants further investigation for FGFR3-fusion harbouring bladder cancers.

VEGF-A, VEGFR1 and VEGFR2 single nucleotide polymorphisms and outcomes from the AGITG MAX trial of capecitabine, bevacizumab and mitomycin C in metastatic colorectal cancer.

The phase III MAX clinical trial randomised patients with metastatic colorectal cancer (mCRC) to receive first-line capecitabine chemotherapy alone or in combination with the anti-VEGF-A antibody bevacizumab (± mitomycin C). We utilised this cohort to examine whether single nucleotide polymorphisms (SNPs) in VEGF-A, VEGFR1, and VEGFR2 are predictive of efficacy outcomes with bevacizumab or the development of hypertension. Genomic DNA extracted from archival FFPE tissue for 325 patients (69% of the MAX trial population) was used to genotype 16 candidate SNPs in VEGF-A, VEGFR1, and VEGFR2, which were analysed for associations with efficacy outcomes and hypertension. The VEGF-A rs25648 'CC' genotype was prognostic for improved PFS (HR 0.65, 95% CI 0.49 to 0.85; P = 0.002) and OS (HR 0.70, 95% CI 0.52 to 0.94; P = 0.019). The VEGF-A rs699947 'AA' genotype was prognostic for shorter PFS (HR 1.32, 95% CI 1.002 to 1.74; P = 0.048). None of the analysed SNPs were predictive of bevacizumab efficacy outcomes. VEGFR2 rs11133360 'TT' was associated with a lower risk of grade ≥ 3 hypertension (P = 0.028). SNPs in VEGF-A, VEGFR1 and VEGFR2 did not predict bevacizumab benefit. However, VEGF-A rs25648 and rs699947 were identified as novel prognostic biomarkers and VEGFR2 rs11133360 was associated with less grade ≥ 3 hypertension.

Rapid Resistance of FGFR-driven Gastric Cancers to Regorafenib and Targeted FGFR Inhibitors can be Overcome by Parallel Inhibition of MEK.

Amplification or overexpression of the FGFR family of receptor tyrosine kinases occurs in a significant proportion of gastric cancers. Regorafenib is a multikinase inhibitor of angiogenic and oncogenic kinases, including FGFR, which showed activity in the randomized phase II INTEGRATE clinical trial in advanced gastric cancer. There are currently no biomarkers that predict response to this agent, and whether regorafenib is preferentially active in FGFR-driven cancers is unknown. Through screening 25 gastric cancer cell lines, we identified five cell lines that were exquisitely sensitive to regorafenib, four of which harbored amplification or overexpression of FGFR family members. These four cell lines were also sensitive to the FGFR-specific inhibitors, BGJ398, erdafitinib, and TAS-120. Regorafenib inhibited FGFR-driven MAPK signaling in these cell lines, and knockdown studies confirmed their dependence on specific FGFRs for proliferation. In the INTEGRATE trial cohort, amplification or overexpression of FGFRs 1-4 was detected in 8%-19% of cases, however, this was not associated with improved progression-free survival and no objective responses were observed in these cases. Further preclinical analyses revealed FGFR-driven gastric cancer cell lines rapidly reactivate MAPK/ERK signaling in response to FGFR inhibition, which may underlie the limited clinical response to regorafenib. Importantly, combination treatment with an FGFR and MEK inhibitor delayed MAPK/ERK reactivation and synergistically inhibited proliferation of FGFR-driven gastric cancer cell lines. These findings suggest that upfront combinatorial inhibition of FGFR and MEK may represent a more effective treatment strategy for FGFR-driven gastric cancers.

First clinical study of a pegylated diabody 124I-labeled PEG-AVP0458 in patients with tumor-associated glycoprotein 72 positive cancers.

Through protein engineering and a novel pegylation strategy, a diabody specific to tumor-associated glycoprotein 72 (TAG-72) (PEG-AVP0458) has been created to optimize pharmacokinetics and bioavailability to tumor. We report the preclinical and clinical translation of PEG-AVP0458 to a first-in-human clinical trial of a diabody. Methods: Clinical translation followed characterization of PEG-AVP0458 drug product and preclinical biodistribution and imaging assessments of Iodine-124 trace labeled PEG-AVP0458 (124I-PEG-AVP0458). The primary study objective of the first-in-human study was the safety of a single protein dose of 1.0 or 10 mg/m2 124I-PEG-AVP0458 in patients with TAG-72 positive relapsed/ metastatic prostate or ovarian cancer. Secondary study objectives were evaluation of the biodistribution, tumor uptake, pharmacokinetics and immunogenicity. Patients were infused with a single-dose of 124I labeled PEG-AVP0458 (3-5 mCi (111-185 MBq) for positron emission tomography (PET) imaging, performed sequentially over a one-week period. Safety, pharmacokinetics, biodistribution, and immunogenicity were assessed up to 28 days after infusion. Results: PEG-AVP0458 was radiolabeled with 124I and shown to retain high TAG-72 affinity and excellent targeting of TAG-72 positive xenografts by biodistribution analysis and PET imaging. In the first-in-human trial, no adverse events or toxicity attributable to 124I-PEG-AVP0458 were observed. Imaging was evaluable in 5 patients, with rapid and highly specific targeting of tumor and minimal normal organ uptake, leading to high tumor:blood ratios. Serum concentration values of 124I-PEG-AVP0458 showed consistent values between patients, and there was no significant difference in T½α and T½ß between dose levels with mean (± SD) results of T½α = 5.10 ± 4.58 hours, T½ß = 46.19 ± 13.06 hours. Conclusions: These data demonstrates the safety and feasibility of using pegylated diabodies for selective tumor imaging and potential delivery of therapeutic payloads in cancer patients.

Genomic Profiling of Biliary Tract Cancer Cell Lines Reveals Molecular Subtypes and Actionable Drug Targets.

Biliary tract cancers (BTCs) currently have no approved targeted therapies. Although genomic profiling of primary BTCs has identified multiple potential drug targets, accurate models are needed for their evaluation. Genomic profiling of 22 BTC cell lines revealed they harbor similar mutational signatures, recurrently mutated genes, and genomic alterations to primary tumors. Transcriptomic profiling identified two major subtypes, enriched for epithelial and mesenchymal genes, which were also evident in patient-derived organoids and primary tumors. Interrogating these models revealed multiple mechanisms of MAPK signaling activation in BTC, including co-occurrence of low-activity BRAF and MEK mutations with receptor tyrosine kinase overexpression. Finally, BTC cell lines with altered ERBB2 or FGFRs were exquisitely sensitive to specific targeted agents, whereas surprisingly, IDH1-mutant lines did not respond to IDH1 inhibitors in vitro. These findings establish BTC cell lines as robust models of primary disease, reveal specific molecular disease subsets, and highlight specific molecular vulnerabilities in these cancers.

Assessment of Simplified Methods for Quantification of 18F-FDHT Uptake in Patients with Metastatic Castration-Resistant Prostate Cancer.

18F-fluorodihydrotestosterone (18F-FDHT) PET/CT potentially provides a noninvasive method for assessment of androgen receptor expression in patients with metastatic castration-resistant prostate cancer (mCRPC). The objective of this study was to assess simplified methods for quantifying 18F-FDHT uptake in mCRPC patients and to assess effects of tumor perfusion on these 18F-FDHT uptake metrics. Methods: Seventeen mCRPC patients were included in this prospective observational multicenter study. Test and retest 30-min dynamic 18F-FDHT PET/CT scans with venous blood sampling were performed in 14 patients. In addition, arterial blood sampling and dynamic 15O-H2O scans were obtained in a subset of 6 patients. Several simplified methods were assessed: Patlak plots; SUV normalized to body weight (SUVBW), lean body mass (SUVLBM), whole blood (SUVWB), parent plasma activity concentration (SUVPP), area under the parent plasma curve (SUVAUC,PP), and area under the whole-blood input curve (SUVAUC,WB); and SUVBW corrected for sex hormone-binding globulin levels (SUVSHBG). Results were correlated with parameters derived from full pharmacokinetic 18F-FDHT and 15O-H2O. Finally, the repeatability of individual quantitative uptake metrics was assessed. Results: Eighty-seven 18F-FDHT-avid lesions were evaluated. 18F-FDHT uptake was best described by an irreversible 2-tissue-compartment model. Replacing the continuous metabolite-corrected arterial plasma input function with an image-derived input function in combination with venous sample data provided similar Ki results (R2 = 0.98). Patlak Ki and SUVAUC,PP showed an excellent correlation (R2 > 0.9). SUVBW showed a moderate correlation to Ki (R2 = 0.70, presumably due to fast 18F-FDHT metabolism. When calculating SUVSHBG, correlation to Ki improved (R2 = 0.88). The repeatability of full kinetic modeling parameters was inferior to that of simplified methods (repeatability coefficients > 36% vs. < 28%, respectively). 18F-FDHT uptake showed minimal blood flow dependency. Conclusion:18F-FDHT kinetics in mCRPC patients are best described by an irreversible 2-tissue-compartment model with blood volume parameter. SUVAUC,PP showed a near-perfect correlation with the irreversible 2-tissue-compartment model analysis and can be used for accurate quantification of 18F-FDHT uptake in whole-body PET/CT scans. In addition, SUVSHBG could potentially be used as an even simpler method to quantify 18F-FDHT uptake when less complex scanning protocols and accuracy are required.

Timing of brain metastases development in metastatic renal cell cancer patients treated with targeted therapies and survival outcomes: An Australian multicenter study.

AIM: Targeted therapy (TT) has improved survival for metastatic renal cell carcinoma (mRCC). However, survival is usually limited if brain metastases (BMs) develop. We aimed to evaluate survival outcomes in mRCC patients based on timing of BM diagnosis. METHODS: We conducted a multicenter, retrospective study of mRCC patients with BM who received TT at any point between 2005 and 2014. We determined overall survival (OS) from stage IV diagnosis, TT initiation and BM diagnosis, and prognostic factors. Patients were grouped into three categories: synchronous-BM, metachronous-BM diagnosed while conservatively managed (metachronous-BM before TT) and metachronous-BM diagnosed during TT. Survival was calculated by Kaplan-Meier method and predictors were calculated using Cox hazards regression. RESULTS: Incidence of BM was 17% in mRCC patients treated with TT (two centers). Fifty-four mRCC-BM patients were identified from five tertiary centers. Twenty-eight percentage (15/54) had synchronous-BM, 28% (15/54) had metachranous-BM before TT and 44% (24/54) had metachronous-BM during TT. Most had central nervous system (CNS) symptoms at BM diagnosis (78%; 42/54). Median OS from stage IV diagnosis, TT commencement and BM diagnosis was 28 months (95% confidence interval [CI] 16-43), 19 months (95% CI 9-26) and 9 months (95% CI 5-16), respectively. Synchronous-BM group trended toward poorer survival from TT commencement (P = 0.06). Metachronous-BM during TT group had lower survival from BM diagnosis than synchronous-BM and metachronous-BM before TT group (P < 0.001). Eight of 50 deaths (16%) were from neurological complications. The presence of CNS symptoms did not predict worse survival from stage IV diagnosis (P = 0.73). CONCLUSION: In patients with mRCC, the development of BM while on TT portends shorter prognosis compared with synchronous diagnosis of BM at stage IV disease or metachronous BM developed prior to commencing TT. The presence of CNS symptoms does not predict worse survival.

Communicating prognosis of patients with advanced cancer between health care providers: a tertiary cancer center review of written correspondence.

BACKGROUND: Communication of prognosis and goals of care between oncologists, community health care providers (HCPs) and patients treated for advanced cancer facilitates optimal care planning. We aimed to review the frequency, content and timing of documented prognosis in written correspondence during the last year of life of advanced cancer patients. METHODS: All patients who died during palliative care or medical oncology admission in 2015 at a large, Australian tertiary center were identified. Patients with incurable solid organ cancer and reviewed ≥1 times in oncology outpatient (OP) clinic were included. We reviewed all oncology OP consultation notes and letters, oncology discharge summaries and advanced care plans over a 12-month period before death. Both internal (OP notes) and external correspondence (OP letters; discharge summaries) were reviewed for documentation of qualitative and quantitative prognosis. RESULTS: One hundred and forty-seven patients were included in the analysis [median age of 70 years, interquartile range (IQR), 58-77 years; males, 60%]. Most patients had a previous inpatient admission (73%). The median OP consultations per patient was 6 (IQR, 2-9) with a median rate of 63% (IQR, 41-87%) resulting in a correspondence letter. The majority of patients had a qualitative statement of prognosis documented in OP notes (63%) and external correspondence letters (61%). However only a minority had a documented quantitative prognosis in either OP notes (14%) or external correspondence letters (7%). The median time from documentation of qualitative and quantitative prognosis to death was 3.5 (IQR, 1.6-6.9) and 2.2 (IQR, 1.1-4.4) months, respectively. While almost all patients had a completed goals-of-care (GOC) form (99%), only 15% of patients had an advanced care plan. CONCLUSIONS: Documentation of qualitative and quantitative prognosis is infrequent despite multiple clinical encounters prior to patient death. This infers inadequate communication between oncologists and other HCPs which reduces insight into patient clinical trajectory and could result in differing care between providers.

Phase Ib Study of High-dose Intermittent Afatinib in Patients With Advanced Solid Tumors.

BACKGROUND: The present phase Ib study assessed the maximum tolerated dose (MTD), safety, pharmacokinetics, and antitumor activity of high-dose intermittent (HDI) afatinib monotherapy for patients with advanced solid tumors. The planned focus was patients with epidermal growth factor receptor (EGFR) T790M+ non-small-cell lung cancer (NSCLC). MATERIALS AND METHODS: Eligible patients had histologically confirmed advanced solid tumors that were unsuitable for, or unresponsive to, standard therapy. The study used a 3+3 design with a starting dose of 90 mg/d for 3 days every 14 days (28-day cycles) and incremental dose escalations to 200 mg/d. RESULTS: Thirty-five patients (18 with NSCLC) were treated (6 at 90 mg; 3 at 120 mg; 9 at 150 mg; 11 at 160 mg; and 6 at 200 mg). One patient in the 90-mg cohort (grade 3 rash) and 2 patients in the 200-mg cohort (grade 3 diarrhea; grade 3 mucositis) experienced a dose-limiting toxicity. The MTD was 160 mg. The most common treatment-related adverse events were diarrhea (total, 88.6%; grade 3, 14.3%), rash/acne (total, 62.9%; grade 3, 2.9%), and fatigue (total, 40.0; grade 3, 0%). The maximum afatinib plasma concentration at the MTD was 313 ng/mL, exceeding the in vitro IC50 (inhibitor concentration decreased by one half) range for T790M inhibition. The trough levels suggested no systematic change in afatinib plasma concentrations during long-term treatment at this dosing schedule. Of the 13 T790M+ NSCLC patients, 1 achieved an objective response (7.7%). CONCLUSION: HDI afatinib was feasible and tolerable and could potentially be further explored for NSCLC indications, including patients with central nervous system disease, rare EGFR mutations, or T790M+ NSCLC intolerant of third-generation EGFR tyrosine kinase inhibitors.

Risk of febrile neutropenia and early treatment cessation in men receiving standard and dose-reduced 3-weekly docetaxel for metastatic castration-resistant prostate cancer.

BACKGROUND: Docetaxel is an effective therapy for metastatic castration-resistant prostate cancer (mCRPC); however, many patients experience febrile neutropenia (FN) and cease treatment early due to toxicity. It is not known whether lower dose (LD) q3-weekly docetaxel impacts toxicity or efficacy. METHODS: Multicenter retrospective study included 166 patients with mCRPC who received q3-weekly docetaxel between 2010 and 2015. Demographic, disease, chemotherapy (standard dose, SD > 60 mg/m2 vs LD ≤ 60 mg/m2 ) and toxicity data were collected. Univariable and multivariable logistic and competing risk regression models evaluated docetaxel-dose association with FN and early treatment cessation (ETC) due to toxicity. Associations between dose and efficacy end points were also evaluated. Analyses were repeated employing inverse propensity score weights. RESULTS: Patients who received LD docetaxel (28.9%) were older with poorer Eastern Cooperative Oncology Group (ECOG) status. Fifteen percent of patients experienced FN, with a nonsignificant trend to lower incidence in the LD group (multiple adjusted odds ratio [OR] = 0.42; P = 0.21). Neither baseline patient nor prior treatment factors were predictive of FN. ETC due to toxicity occurred in 35%, with risk associated with increasing age, comorbidity count and poorer ECOG. There was no difference between LD and SD with respect to ETC due to toxicity, in unweighted and weighted analyses (LD vs SD, multivariable weighted hazard ratio [HR] = 1.47; P = 0.08). LD was associated with reduced prostate-specific antigen (PSA) response (50% vs 66.1%, multivariable weighted HR = 0.54; P = 0.03) and overall survival (median 7.9 vs 13.8 months, multivariable weighted HR = 2.19; P < 0.0001). CONCLUSIONS: LD docetaxel for mCRPC did not mitigate the risk of FN or ETC due to toxicity. Dose reduction may result in poorer PSA response and survival.

Survival and functional outcomes of patients with metastatic solid organ cancer admitted to the intensive care unit of a tertiary centre.

OBJECTIVE: Metastatic solid organ cancer is associated with a poor prognosis, and admission of patients with these cancers to the intensive care unit remains a dilemma. We aimed to assess outcomesin a cohort of these patients who were admitted to the ICU of a general tertiary centre. DESIGN, SETTING AND PATIENTS: A retrospective observational study of patients with incurable metastatic solid organ malignancies who had unplanned admission to a tertiary hospital ICU between 1 January 2010 and 30 June 2015. MAIN OUTCOME MEASURES: Survival outcomes up to 1 year after ICU admission, and functional outcomes as measured by Eastern Cooperative Oncology Group (ECOG) grade up to 3 months after ICU discharge. We also determined rates of advance care planning documentation. RESULTS: A total of 101 patients were treated in the ICU during the study period. Hospital, 30-day and 1-year mortality rates were 35%, 41% and 77%, respectively, and the median survival was 2.3 months (95% CI, 1.1-3.9 months). On multivariable analysis, lowest albumin level (hazard ratio [HR], 1.10; 95% CI, 1.04-1.15) and highest white cell count (HR, 1.03; 95% CI, 1.00-1.07) were significant, although they were marginal predictors of poorer overall survival. Higher ECOG grade showed a trend towards significance (HR, 1.60; 95% CI, 0.94-2.73; P = 0.08). In patients alive and assessable at 1 month, 17/31 (55%) had functionally declined. At 3 months, 15/22 surviving patients (68%) had returned to their baseline, pre-ICU admission ECOG grade. Ninety per cent had no advance care directive and twothirds did not have a medical enduring power of attorney. CONCLUSIONS: Survival is poor in patients with metastatic cancer after emergent ICU admission, although functional state is often recovered by 3 months in surviving patients. Albumin level, white cell count and ECOG grade are simple prognostic markers of survival.

K-Ras mutation and amplification status is predictive of resistance and high basal pAKT is predictive of sensitivity to everolimus in biliary tract cancer cell lines.

Advanced biliary tract cancer (BTC) has a poor prognosis and limited treatment options. The PI3K/Akt/mTOR signalling pathway is hyperactivated in a subset of BTCs, and clinical activity of the mTOR inhibitor everolimus has been observed in some patients with BTC. The goal of this study was to identify biomarkers predictive of everolimus response. Twenty BTC cell lines were assessed for everolimus sensitivity with a spectrum of growth inhibitory responses observed. Molecular biomarkers of sensitivity and resistance were identified by interrogation of the activation status of the Ras/MAPK and PI3K/Akt/mTOR pathways. K-Ras mutations and/or amplifications were identified in 45% of cell lines and were associated with resistance to everolimus. Activating mutations in PIK3CA or loss of PTEN was not predictive of everolimus response; however, high basal levels of pAKT were associated with sensitivity, independent of Ras/MAPK pathway activation status. Notably, everolimus inhibited mTOR signalling to a similar extent in sensitive and resistant cell lines, suggesting that relative dependence on the mTOR pathway rather than the magnitude of pathway inhibition determines everolimus response. Consistent with the known limitations of rapalogs, everolimus induced feedback-mediated activation of AKT in BTC cell lines, which could be overcome by cotreatment with an AKT inhibitor or ATP-competitive mTORC1/mTORC2 inhibitors. However, both approaches failed to induce greater apoptosis compared to everolimus, and mTORC1/mTORC2 kinase inhibitors induced compensatory activation of pERK, identifying an inherent limitation of these agents in BTC cell lines. These findings suggest that future trials of everolimus in BTC would benefit from preselecting patients based on their K-Ras and PI3K/mTOR pathway activation status. The study also identifies strategies for enhancing inhibition of the PI3K/mTOR pathway in BTC cell lines.

Stereotactic radiation therapy can safely and durably control sites of extra-central nervous system oligoprogressive disease in anaplastic lymphoma kinase-positive lung cancer patients receiving crizotinib.

PURPOSE: To analyze the durability and toxicity of radiotherapeutic local ablative therapy (LAT) applied to extra-central nervous system (eCNS) disease progression in anaplastic lymphoma kinase-positive non-small cell lung cancer (NSCLC) patients. METHODS AND MATERIALS: Anaplastic lymphoma kinase-positive NSCLC patients receiving crizotinib and manifesting ≤ 4 discrete sites of eCNS progression were classified as having oligoprogressive disease (OPD). If subsequent progression met OPD criteria, additional courses of LAT were considered. Crizotinib was continued until eCNS progression was beyond OPD criteria or otherwise not suitable for further LAT. RESULTS: Of 38 patients, 33 progressed while taking crizotinib. Of these, 14 had eCNS progression meeting OPD criteria suitable for radiotherapeutic LAT. Patients with eCNS OPD received 1-3 courses of LAT with radiation therapy. The 6- and 12-month actuarial local lesion control rates with radiation therapy were 100% and 86%, respectively. The 12-month local lesion control rate with single-fraction equivalent dose >25 Gy versus ≤ 25 Gy was 100% versus 60% (P=.01). No acute or late grade >2 radiation therapy-related toxicities were observed. Median overall time taking crizotinib among those treated with LAT versus those who progressed but were not suitable for LAT was 28 versus 10.1 months, respectively. Patients continuing to take crizotinib for >12 months versus ≤ 12 months had a 2-year overall survival rate of 72% versus 12%, respectively (P<.0001). CONCLUSIONS: Local ablative therapy safely and durably eradicated sites of individual lesion progression in anaplastic lymphoma kinase-positive NSCLC patients receiving crizotinib. A dose-response relationship for local lesion control was observed. The suppression of OPD by LAT in patients taking crizotinib allowed an extended duration of exposure to crizotinib, which was associated with longer overall survival.

Drug-induced reduction in estimated glomerular filtration rate in patients with ALK-positive non-small cell lung cancer treated with the ALK inhibitor crizotinib.

BACKGROUND: To the best of the authors' knowledge, the renal side effects of crizotinib have not been investigated previously. METHODS: The estimated glomerular filtration rate (eGFR) was calculated using the Chronic Kidney Disease Epidemiology Collaboration creatinine-based prediction equation during the first 12 weeks of crizotinib therapy and after crizotinib but before the introduction of any further systemic therapy. RESULTS: A total of 38 patients with stage IV anaplastic lymphoma kinase (ALK)-positive non-small cell lung cancer who were treated with crizotinib were identified. The mean eGFR decreased by 23.9% compared with baseline (P < .0001; 95% confidence interval, 21.3%-26.6%), with the majority of the decrease occurring within the first 2 weeks of therapy. Clinical history and blood urea nitrogen/creatinine ratios did not suggest prerenal causes. The objective response rate among evaluable patients (n = 27) was 41%. Tumor shrinkage was not correlated with changes in eGFR (correlation coefficient, -0.052; P = .798). Among the 16 patients for whom data after treatment with crizotinib were available, recovery to within 84% of the baseline eGFR occurred in all patients. After adjusting for the number of scans with intravenous contrast and the use of known nephrotoxic drugs, the issue of whether a patient was on or off crizotinib treatment was found to be significantly associated with changes in eGFR (P < .0001). CONCLUSIONS: As assessed by the Chronic Kidney Disease Epidemiology Collaboration prediction equation, eGFR is reduced by treatment with crizotinib, but the majority of patients will recover their eGFR after the cessation of therapy. The early onset, size of the change, minimal cumulative effect, and rapid reversibility raise the possibility that this may be a pharmacological and/or tubular creatinine secretion effect rather than a direct nephrotoxic effect. Increased vigilance with regard to the concomitant use of renally cleared medications or nephrotoxic agents should be considered for patients receiving crizotinib and, when eGFR is reduced, additional renal investigations should be undertaken.

ROS1 and ALK fusions in colorectal cancer, with evidence of intratumoral heterogeneity for molecular drivers.

UNLABELLED: Activated anaplastic lymphoma kinase (ALK) and ROS1 tyrosine kinases, through gene fusions, have been found in lung adenocarcinomas and are highly sensitive to selective kinase inhibitors. This study aimed at identifying the presence of these rearrangements in human colorectal adenocarcinoma specimens using a 4-target, 4-color break-apart FISH assay to simultaneously determine the genomic status of ALK and ROS1. Among the clinical colorectal cancer specimens analyzed, rearrangement-positive cases for both ALK and ROS1 were observed. The fusion partner for ALK was identified as EML4 and the fusion partner for one of the ROS1-positive cases was SLC34A2, the partner for the other ROS1-positive case remains to be identified. A small fraction of specimens presented duplicated or clustered copies of native ALK and ROS1. In addition, rearrangements were detected in samples that also harbored KRAS and BRAF mutations in two of the three cases. Interestingly, the ALK-positive specimen displayed marked intratumoral heterogeneity and rearrangement was also identified in regions of high-grade dysplasia. Despite the additional oncogenic events and tumor heterogeneity observed, elucidation of the first cases of ROS1 rearrangements and confirmation of ALK rearrangements support further evaluation of these genomic fusions as potential therapeutic targets in colorectal cancer. IMPLICATIONS: ROS1 and ALK fusions occur in colorectal cancer and may have substantial impact in therapy selection.

Symptomatic reduction in free testosterone levels secondary to crizotinib use in male cancer patients.

BACKGROUND: Crizotinib is a tyrosine kinase inhibitor active against ALK, MET, and ROS1. We previously reported that crizotinib decreases testosterone in male patients. The detailed etiology of the effect, its symptomatic significance, and the effectiveness of subsequent testosterone replacement have not been previously reported. METHODS: Male cancer patients treated with crizotinib had total testosterone levels measured and results compared with non-crizotinib-treated patients. Albumin, sex hormone-binding globulin (SHBG), follicle-stimulating hormone (FSH), and/or luteinizing hormone (LH) were tracked longitudinally. A subset of patients had free testosterone levels measured and a hypogonadal screening questionnaire administered. Patients receiving subsequent testosterone supplementation were assessed for symptomatic improvement. RESULTS: Mean total testosterone levels were -25% below the lower limit of normal (LLN) in 32 crizotinib-treated patients (27 of 32 patients below LLN, 84%) compared with +29% above LLN in 19 non-crizotinib-treated patients (6 of 19 below LLN, 32%), P = .0012. Levels of albumin and SHBG (which both bind testosterone) declined rapidly with crizotinib, but so did FSH, LH, and free testosterone, suggesting a centrally mediated, true hypogonadal effect. Mean free testosterone levels were -17% below LLN (19 of 25 patients below LLN, 76%). Eighty-four percent (16 of 19) with low free levels, and 79% (19/24) with low total levels had symptoms of androgen deficiency. Five of 9 patients (55%) with low testosterone given testosterone supplementation had improvement in symptoms, coincident with increases in testosterone above LLN. CONCLUSIONS: Symptoms of androgen deficiency and free or total/free testosterone levels should be tracked in male patients on crizotinib with consideration of testosterone replacement as appropriate.

Diagnostic assays for identification of anaplastic lymphoma kinase-positive non-small cell lung cancer.

In series dominated by adenocarcinoma histology, approximately 5% of non-small cell lung cancers (NSCLCs) harbor an anaplastic lymphoma kinase (ALK) gene rearrangement. Crizotinib, a tyrosine kinase inhibitor with significant activity against ALK, has demonstrated high response rates and prolonged progression-free survival in ALK-positive patients enrolled in phase 1/2 clinical trials. In 2011, crizotinib received accelerated approval from the US Food and Drug Administration (FDA) for the treatment of proven ALK-positive NSCLC using an FDA-approved diagnostic test. Currently, only break-apart fluorescence in situ hybridization testing is FDA approved as a companion diagnostic for crizotinib; however, many other assays are available or in development. In the current review, the authors summarize the diagnostic tests available, or likely to become available, that could be used to identify patients with ALK-positive NSCLC, highlighting the pros and cons of each.

Local ablative therapy of oligoprogressive disease prolongs disease control by tyrosine kinase inhibitors in oncogene-addicted non-small-cell lung cancer.

INTRODUCTION: Many patients with oncogene-driven non-small-cell lung cancer (NSCLC) treated with tyrosine kinase inhibitors experience limited sites of disease progression. This study investigated retrospectively the benefits of local ablative therapy (LAT) to central nervous system (CNS) and/or limited systemic disease progression and continuation of crizotinib or erlotinib in patients with metastatic ALK gene rearrangement (ALK+) or EGFR-mutant (EGFR-MT) NSCLC, respectively. METHODS: Patients with metastatic ALK+ NSCLC treated with crizotinib (n = 38) and EGFR-MT NSCLC treated with erlotinib (n = 27) were identified at a single institution. Initial response to the respective kinase inhibitors, median progression-free survival (PFS1), and site of first progression were recorded. A subset of patients with either nonleptomeningeal CNS and/or four sites or fewer of extra-CNS progression (oligoprogressive disease) suitable for LAT received either radiation or surgery to these sites and continued on the same tyrosine kinase inhibitors. The subsequent median progression-free survival from the time of first progression (PFS2) and pattern of progression were recorded. RESULTS: Median progression-free survival in ALK+ patients on crizotinib was 9.0 months, and 13.8 months for EGFR-MT patients on erlotinib. Twenty-five of 51 patients (49%) who progressed were deemed suitable for local therapy (15 ALK+, 10 EGFR-MT; 24 with radiotherapy, one with surgery) and continuation of the same targeted therapy. Post-LAT, 19 of 25 patients progressed again, with median PFS2 of 6.2 months. DISCUSSION: Oncogene-addicted NSCLC with CNS and/or limited systemic disease progression (oligoprogressive disease) on relevant targeted therapies is often suitable for LAT and continuation of the targeted agent, and is associated with more than 6 months of additional disease control.

Rapid-onset hypogonadism secondary to crizotinib use in men with metastatic nonsmall cell lung cancer.

BACKGROUND: The objective of this study was to document the differences in testosterone (T) levels between crizotinib-treated and noncrizotinib-treated patients with metastatic nonsmall cell lung cancer (NSCLC). METHODS: Testosterone levels were measured in 19 men with metastatic NSCLC who received crizotinib and in 19 men with metastatic NSCLC who did not receive crizotinib. Clinical characteristics of the patients were compared, and additional hormone assays were performed as appropriate. Two patients who began crizotinib and 4 patients who had dose interruptions or who stopped crizotinib therapy had serial hormone measurements, permitting the documentation of dynamic hormone changes on and off crizotinib treatment. RESULTS: Total T levels were low (<241 ng/dL) in 19 of 19 (100%) crizotinib-treated men and in 6 of 19 men (32%) with metastatic NSCLC who did not receive crizotinib (mean T levels, 131 ng/dL and 311 ng/dL, respectively; P = .0002). Only 1 in 5 patients who had anaplastic lymphoma kinase (ALK) gene rearrangements and had not yet received crizotinib had low T. The initiation of crizotinib in 2 patients who had previously normal T levels was associated with a rapid decreases in T and in luteinizing hormone and follicle stimulating hormone levels within 14 to 21 days. Discontinuation of crizotinib led to increases back to normal T levels. CONCLUSIONS: Crizotinib therapy caused rapid suppression of T levels in men. The current results indicated that the site of action must include a central (hypothalamic or pituitary) effect, but additional direct testicular effects could not be excluded. Further work is required to assess the correlation between low T levels and crizotinib side effects as well as the exact molecular mechanism and site of drug toxicity.