Phase II study of trifluridine/tipiracil in metastatic breast cancers with or without prior exposure to fluoropyrimidines.

BACKGROUND: Fluoropyrimidines are commonly used in the treatment of metastatic breast cancer (MBC), and trifluridine/tipiracil (FTD/TPI) has shown activity in patients with colorectal and gastric cancers despite prior exposure to fluoropyrimidines. We investigate the role of FTD/TPI in patients with MBC with or without prior fluoropyridines in a single-arm phase II study. METHODS: Patients with MBC were enroled first into a run-in dose confirmation phase, followed by two parallel cohorts including patients with (Cohort A) and without (Cohort B) prior exposure to fluoropyrimidines, where they were treated with FTD/TPI. Primary objectives for each cohort included determination of progression-free survival (PFS), and secondary objectives included determination of objective response rates (ORR), safety, and tolerability. RESULTS: Seventy-four patients (42 Cohort A, 32 Cohort B) were enroled, all of whom were evaluable for toxicity and survival, with 72 evaluable for response. Median PFS was 5.7 months (95% confidence interval 3.8-8.3) and 9.4 months (95% CI 5.5-14.0) respectively in Cohorts A and B. Responses were observed regardless of prior exposure to fluoropyrimidines, with ORR of 19.5% (95% CI 8.8-34.9) and 16.1% (95% CI 5.5-33.7) in Cohorts A and B, and 6-month clinical benefit rates of 56.1% (95% CI 39.7-71.5) and 61.3% (95% CI 42.2-78.2) respectively. The safety profile was consistent with known toxicities of FTD/TPI, including neutropenia, fatigue, nausea, and anorexia, mitigated with dose modifications. CONCLUSION: FTD/TPI showed promising antitumour activity with manageable toxicity and is a clinically valid option in patients with MBC.

Serial Tumor Molecular Profiling of Newly Diagnosed HER2-Negative Breast Cancers During Chemotherapy in Combination with Angiogenesis Inhibitors.

BACKGROUND: Breast cancers are heterogeneous with variable clinical courses and treatment responses. OBJECTIVE: We sought to evaluate dynamic changes in the molecular landscape of HER2-negative tumors treated with chemotherapy and anti-angiogenic agents. PATIENTS AND METHODS: Newly diagnosed HER2-negative breast cancer patients received low-dose sunitinib or bevacizumab prior to four 2-weekly cycles of dose-dense doxorubicin and cyclophosphamide. Tumor biopsies were obtained at baseline, after 2 weeks and after 8 weeks of chemotherapy. Next-generation sequencing was performed to assess for single nucleotide variants (SNVs) and copy number alterations (CNAs) of 440 cancer-related genes (ACTOnco®). Observed genomic changes were correlated with the Miller-Payne histological response to treatment. RESULTS: Thirty-four patients received sunitinib and 18 received bevacizumab. In total, 77% were hormone receptor positive (HER2-/HR+) and 23% were triple negative breast cancers (TNBC). New therapy-induced mutations were infrequent, occurring only in 13%, and appeared early after a single cycle of treatment. Seventy-two percent developed changes in the variant allele frequency (VAF) of pathogenic SNVs; the majority (51%) of these changes occurred early at 2 weeks and were sustained for 8 weeks. Changes in VAF of SNVs were most commonly seen in the PI3K/mTOR/AKT pathway; 13% developed changes in pathogenic mutations, which potentially confer sensitivity to PIK3CA inhibitors. Tumors with poor Miller-Payne response to treatment were less likely to experience changes in VAF of SNVs compared with those with good response (50% [7/14] vs 15% [4/24] had no changes observed at any timepoint, p = 0.029). CONCLUSIONS: Serial molecular profiling identifies early therapy-induced genomic alterations, which may guide future selection of targeted therapies in breast cancer patients who progress after standard chemotherapy. CLINICAL TRIAL REGISTRATION: ClinicalTrials.gov: NCT02790580 (first posted June 6, 2016).

Phase Ib/II Dose Expansion Study of Lenvatinib Combined with Letrozole in Postmenopausal Women with Hormone Receptor-Positive Breast Cancer.

PURPOSE: RET is an estrogen response gene with preclinical studies demonstrating cross-talk between the RET and estrogen receptor (ER) pathways. We investigate the role of lenvatinib, a multikinase inhibitor with potent activity against RET, in patients with metastatic breast cancer. PATIENTS AND METHODS: Patients with advanced ER+/HER2- breast cancer were treated with lenvatinib plus letrozole in a phase Ib/II trial. Primary objectives included safety and recommended phase II dose (RP2D) determination in phase Ib, and objective response rates (ORR) in phase II dose expansion. RESULTS: Sixteen patients were recruited in dose finding, where deescalating doses of lenvatinib from 20 to 14 mg were investigated. Lenvatinib 14 mg plus letrozole 2.5 mg daily was determined as RP2D. Thirty-one patients with 5 median lines of prior therapy in the metastatic setting (range, 0-11) were recruited in dose expansion. In this cohort, ORR was 23.3% [95% confidence interval (CI) 9.9%-42.3%], with median duration of response (DoR) of 6.9 months [interquartile range (IQR) 5.9 to 13.1]. Clinical benefit rate ≥6 months (CBR) was 50.0% (95% CI, 31.3%-68.7%). Similar efficacy was observed in the subgroup of 25 patients who progressed on prior CDK4/6 inhibitor therapy [ORR 20.0% (95% CI, 6.8%-40.7%), median DoR 6.9 months (IQR 5.9-13.1), and CBR 52.0% (95% CI, 31.3%-72.2%)]. Pharmacodynamic studies showed target modulation, with paired tumor biopsies indicating downregulation of RET/pERK and improved vascular normalization index. CONCLUSIONS: Lenvatinib plus letrozole had manageable toxicity, with target engagement and preliminary antitumor activity observed, supporting further assessment in randomized studies.

A randomized phase II trial evaluating the addition of low dose, short course sunitinib to docetaxel in advanced solid tumours.

BACKGROUND: We previously reported that low-dose, short-course sunitinib prior to neoadjuvant doxorubicin-cyclophosphamide (AC) normalised tumour vasculature and improved perfusion, but resulted in neutropenia and delayed subsequent cycles in breast cancer patients. This study combined sunitinib with docetaxel, which has an earlier neutrophil nadir than AC. METHODS: Patients with advanced solid cancers were randomized 1:1 to 3-weekly docetaxel 75 mg/m2, with or without sunitinib 12.5 mg daily for 7 days prior to docetaxel, stratified by primary tumour site. Primary endpoints were objective-response (ORR:CR + PR) and clinical-benefit rate (CBR:CR + PR + SD); secondary endpoints were toxicity and progression-free-survival (PFS). RESULTS: We enrolled 68 patients from 2 study sites; 33 received docetaxel-sunitinib and 35 docetaxel alone, with 33 breast, 25 lung and 10 patients with other cancers. There was no difference in ORR (30.3% vs 28.6%, p = 0.432, odds-ratio [OR] 1.10, 95% CI 0.38-3.18); CBR was lower in the docetaxel-sunitinib arm (48.5% vs 71.4%, p = 0.027 OR 0.37, 95% CI 0.14-1.01). Median PFS was shorter in the docetaxel-sunitinib arm (2.9 vs 4.9 months, hazard-ratio [HR] 2.00, 95% CI 1.15-3.48, p = 0.014) overall, as well as in breast (4.2 vs 5.6 months, p = 0.048) and other cancers (2.0 vs 5.3 months, p = 0.009), but not in lung cancers (2.9 vs 4.1 months, p = 0.597). Median OS was similar in both arms overall (9.9 vs 10.5 months, HR 0.92, 95% CI 0.51-1.67, p = 0.789), and in the breast (18.9 vs 25.8 months, p = 0.354), lung (7.0 vs 6.7 months, p = 0.970) and other cancers (4.5 vs 8.8 months, p = 0.449) subgroups. Grade 3/4 haematological toxicities were lower with docetaxel-sunitinib (18.2% vs 34.3%, p = 0.132), attributed to greater discretionary use of prophylactic G-CSF (90.9% vs 63.0%, p = 0.024). Grade 3/4 non-haematological toxicities were similar (12.1% vs 14.3%, p = 0.792). CONCLUSIONS: The addition of sunitinib to docetaxel was well-tolerated but did not improve outcomes. The possible negative impact in metastatic breast cancer patients is contrary to results of adding sunitinib to neoadjuvant AC. These negative results suggest that the intermittent administration of sunitinib in the current dose and schedule with docetaxel in advanced solid tumours, particularly breast cancers, is not beneficial. TRIAL REGISTRATION: The study was registered ( NCT01803503 ) prospectively on clinicaltrials.gov on 4th March 2013.

Phase I Trial of Expanded, Activated Autologous NK-cell Infusions with Trastuzumab in Patients with HER2-positive Cancers.

PURPOSE: Natural killer (NK) cells exert antibody-dependent cell cytotoxicity (ADCC). We infused expanded, activated autologous NK cells to potentiate trastuzumab-mediated ADCC in patients with HER2-positive malignancies. PATIENTS AND METHODS: In a phase I trial, patients with treatment-refractory HER2-positive solid tumors received trastuzumab, with or without bevacizumab, and autologous NK cells expanded by 10-day coculture with K562-mb15-41BBL cells. Primary objectives included safety and recommended phase II dose determination; secondary objectives included monitoring NK-cell activity and RECIST antitumor efficacy. RESULTS: In 60 cultures with cells from 31 subjects, median NK-cell expansion from peripheral blood was 340-fold (range, 91-603). NK cells expressed high levels of CD16, the mediator of ADCC, and exerted powerful killing of trastuzumab-targeted cells. In the 22 subjects enrolled in phase I dose escalation, trastuzumab plus NK cells were well tolerated; MTD was not reached. Phase IB (n = 9) included multiple cycles of NK cells (1 × 107/kg) and addition of bevacizumab. Although no objective response was observed, 6 of 19 subjects who received at least 1 × 107/kg NK cells at cycle 1 had stable disease for ≥6 months (median, 8.8 months; range 6.0-12.0). One patient, the only one with the high-affinity F158V CD16 variant, had a partial response. Peripheral blood NK cells progressively downregulated CD16 postinfusion; paired tumor biopsies showed increased NK cells, lymphocytic infiltrates, and apoptosis posttreatment. CONCLUSIONS: NK-cell therapy in combination with trastuzumab was well tolerated, with target engagement and preliminary antitumor activity, supporting continued assessment of this approach in phase II trials.

Nurse-Led Vital Signs Monitoring Can Safely Identify Low-Risk Hematology-Oncology Patients For De-Escalation.

PURPOSE: It is routine practice for patients to be on vital signs monitoring (VSM) once every 4 hours, which is laborious and disruptive. VSM de-escalation has been demonstrated to be safe in low-risk (LR) patients, but it has not been well studied in the hematology-oncology setting. METHODS: A quality improvement project was conducted in 3 hematology-oncology inpatient wards within a comprehensive cancer center, from March 2017 to July 2017 (pilot phase) and from October 2017 to Sept 2018 (maintenance phase). Root causes for frequent VSM identified via problem analysis include (1) perception of VSM, (2) lack of concise clinical guidelines, and (3) lack of nurse empowerment. Consensus criteria to define suitable LR patients and a nurse-led VSM de-escalation protocol were formulated. RESULTS: Of 1,065 patients who underwent nurse-led VSM de-escalation, there was a 50% reduction in the mean number of nurse encounters (NE) per month (P < .01), with total savings of 2,731.5 NE-minutes per month. VSM re-escalation was required by 10.1% of patients; all were deemed unpreventable with more frequent VSM and none resulted in severe adverse outcomes. With additional interventions such as spot audits and retraining, recruitment for de-escalation improved from 51.7% of LR admissions in the pilot phase to 93.8% in the maintenance phase (P < .01). The time saved was used to enhance other aspects of patient care, such as patient education. One hundred thirty-nine of 169 doctors and nurses surveyed after implementation (96.5%) supported continuing this protocol. CONCLUSION: A well-defined protocol allows safe nurse-led de-escalation of VSM for LR patients without adverse outcomes and was shown to be sustainable in this cohort of hematology-oncology patients.

Next Generation Sequencing Reveals Novel Mutations in Mismatch Repair Genes and Other Cancer Predisposition Genes in Asian Patients with Suspected Lynch Syndrome.

BACKGROUND: Although at least 5 genes are implicated in Lynch Syndrome (LS), up to 50% of suspected cases are owing to undefined genes. We utilized next generation sequencing (NGS) to characterize the mutation profile of patients with cancer (CA) suspected to have LS. PATIENTS AND METHODS: We enrolled 174 Asian patients with CA from our CA Genetics Clinic from 2000 to 2014 suspected to have LS, and obtained germline DNA for NGS using TruSight Cancer. Frameshift, nonsense, and known deleterious mutations were considered pathogenic. Polymorphisms ≤ 1% frequency in 1000 Genomes (Asian) were classified using established databases. RESULTS: Of the 174 probands, 80.5% were Chinese, the median age at CA diagnosis was 45 years (range, 18-82 years), and 84.5% and 8.6% had colon and LS-like CA, respectively. Forty-seven of 100 evaluable colon CA probands had LS-like histopathologic features. Nineteen of 174 had family history fulfilling Amsterdam I/II Criteria, whereas the rest fulfilled Bethesda Guidelines. Thirty-one of 174 harbored pathogenic mutations with 10 in LS genes only, 20 in non-LS genes only, and 1 in both. Of the 11 with LS gene mutations, MLH1 was most commonly involved (n = 7), followed by MSH2, MSH6, and PMS2. Nine of 174 had pathogenic mutations diagnostic of alternative hereditary syndromes including 2 each in CDH1, APC, and BRCA1, and 1 each in BRCA2, SMAD4, and MUTYH. Ten unique mutations were detected in low-to-moderate penetrance genes: 6 individuals had a recurring novel KIT:c.2836C>T nonsense mutation (n = 3) or ERCC4:c.2169C>A nonsense mutation (n = 3) without LS gene mutation, which is of clinical interest. CONCLUSIONS: In this Asian study, NGS proved to be feasible in screening for causative mutations in patients with CA suspected to have LS.

Clinical genetic testing outcome with multi-gene panel in Asian patients with multiple primary cancers.

BACKGROUND: Developing multiple cancers is an indicator of underlying hereditary cancer predisposition, but there is a paucity of data regarding the clinical genetic testing outcomes of these patients. METHODS: We compared cancer index patients with ≥2 primary malignancies versus 1 primary cancer who underwent clinical evaluation and testing with multi-gene panels comprising up to 49 genes from 1998-2016. RESULTS: Among 1191 cancer index patients, 80.6%, 17.2%, and 2.2% respectively had 1, 2, and ≥3 primary malignancies. For patients with 2 primary cancers (n=205), the most common cancer pairs were bilateral breast (37.5%), breast-ovary (11.7%), endometrium-ovary (9.2%), colon-endometrium (3.9%) and colon-colon (3.4%). 42.3% patients underwent gene testing including 110/231 (47.6%) with multiple malignancies. Pathogenic variants were found more frequently in younger patients, in those with a family history of cancer related to the suspected syndrome, and a trend towards significance in those with multiple primary cancers (35.5% vs. 25.6%, p = 0.09). In patients with multiple cancers, pathogenic variants were most commonly identified in BRCA1 (38.5%), BRCA2 (17.9%), and the mismatch repair genes (20.5%), while 23.1% of pathogenic mutations were in other moderate- to high-penetrance cancer predisposition genes including APC, ATM, MUTYH, PALB2, RAD50 and TP53. CONCLUSION: Patients with multiple cancers were more likely to carry pathogenic mutations than those with single cancer. About three-quarters of deleterious mutations in patients with multiple primary cancers were in BRCA1/2 and the mismatch repair genes, but multi-gene panel testing facilitated the detection of mutations in another 6 genes and is warranted in this high-risk population.

Phase Ib/II randomized, open-label study of doxorubicin and cyclophosphamide with or without low-dose, short-course sunitinib in the pre-operative treatment of breast cancer.

BACKGROUND: Prolonged anti-angiogenic therapy destroys tumor vasculature, whereas vascular-normalizing doses may enhance intra-tumoral drug delivery. We hypothesize that low-dose, short-course sunitinib normalizes vasculature, enhancing chemotherapy efficacy. PATIENTS AND METHODS: In phase Ib, treatment-naïve breast cancer patients received four cycles of pre-operative doxorubicin/cyclophosphamide, with sunitinib before each cycle. The optimal dose of sunitinib leading to tumor vessel normalization on immunohistochemistry was identified. In phase II, subjects were randomized to chemotherapy alone or chemotherapy plus sunitinib at the recommended phase II dose (RP2D). Primary endpoint was pathological complete response (pCR) rate. Tumor and functional imaging biomarkers were evaluated serially. RESULTS: In phase Ib (n=9), sunitinib 12.5 mg daily for 7 days before each chemotherapy was established as RP2D. In phase II, patients receiving chemotherapy plus sunitinib (n=24) had similar pCR rates (5.0% versus 4.3%, p=1.00), but a higher incidence of chemotherapy dose delays (33.3% versus 8.7%, p=0.04), compared to those receiving chemotherapy alone (n=25). The addition of sunitinib to chemotherapy significantly increased vascular normalization index (VNI) and decreased lymphatic vessel density (D2-40) on immunohistochemistry [VNI:25.50±27.94% versus 49.29±31.84%, p=0.034; D2-40:3.29±2.70 versus 1.29±1.54, p=0.014, baseline versus post-cycle 1], and improved perfusion on DCE-MRI (Ktrans:12.6±9.6 mL/100 g/min versus 16.3±10.7 mL/100 g/min, baseline versus post-cycle 1, p=0.015). Conversely, immunohistochemical and DCE-MRI parameters were not significantly altered by chemotherapy alone. CONCLUSION: Low-dose, short-course sunitinib prior to anthracycline-based chemotherapy in breast cancer patients did not improve pCR and increased chemotherapy dose delays. However, the addition of sunitinib induced compelling pharmacodynamic evidence of vascular normalization. Further studies with alternative cytotoxic regimens should be explored.

Short-term expansion of breast circulating cancer cells predicts response to anti-cancer therapy.

Circulating tumor cells (CTCs) are considered as surrogate markers for prognosticating and evaluating patient treatment responses. Here, 226 blood samples from 92 patients with breast cancer, including patients with newly diagnosed or metastatic refractory cancer, and 16 blood samples from healthy subjects were cultured in laser-ablated microwells. Clusters containing an increasing number of cytokeratin-positive (CK+) cells appeared after 2 weeks, while most blood cells disappeared with time. Cultures were heterogeneous and exhibited two distinct sub-populations of cells: 'Small' (≤ 25 µm; high nuclear/cytoplasmic ratio; CD45-) cells, comprising CTCs, and 'Large' (> 25 µm; low nuclear/cytoplasmic ratio; CD68+ or CD56+) cells, corresponding to macrophage and natural killer-like cells. The Small cell fraction also showed copy number increases in six target genes (FGFR1, Myc, CCND1, HER2, TOP2A and ZNF217) associated with breast cancer. These expanded CTCs exhibited different proportions of epithelial-mesenchymal phenotypes and were transferable for further expansion as spheroids in serum-free suspension or 3D cultures. Cluster formation was affected by the presence and duration of systemic therapy, and its persistence may reflect therapeutic resistance. This novel and advanced method estimates CTC clonal heterogeneity and can predict, within a relatively short time frame, patient responses to therapy.