Abstract OT1-1-10: CirCe T-DM1 phase II trial: Assessing the relevance of HER2-amplified circulating tumor cells as a tool to select HER2-negative metastatic breast cancer for treatment with T-DM1

Background: T-DM1 has demonstrated its efficacy in the second line of HER2-positive metastatic breast cancer patients. Several studies reported that some breast cancers considered as HER2-negative do have HER2-positive circulating tumor cells (CTC). Our previous report (Lightart & Bidard, Ann Oncol 2013) showed that the reliability of such discrepancy between primary tumor and CTC is directly related to the number of CTC analyzed. This study aims at studying the efficacy of T-DM1 in this setting.

Trial design: CirCe T-DM1 is a single arm two-step phase II multicenter study with adaptive design. Patients with HER2-negative measurable metastatic breast cancer will be screened by the FDA-approved CellSearch system, before the start of a second line treatment. HER2/CEP17 ratio will be quantified by FISH on CTC (Veridex). Patients with non HER2-amplified CTC or no CTC will be excluded from the study. Patients with HER2-amplified CTC will be treated by T-DM1 (Roche) single agent q3w, in either cohort “L” (low count: 1 to 4 HER2-amplified CTC) or in cohort “H” (high count: 5 or more HER2-amplified CTC). 14 patients (7L+7H) will be included in the first step. If needed, the second step will include 14 additional patients (7L+7H). Tumor response (per RECIST criteria) is the main objective of the trial.

Eligibility criteria: main criteria are HER2-negative metastatic breast cancer; measurable disease progressing after a first line treatment; PS 0-1; criteria related to T-DM1 treatment and ethics. Only patients with HER2-positive CTC will be treated by t-DM1.

Specific aim: this study will assess the response rate to T-DM1 in patients with HER2-amplified CTC and HER2-negative metastatic breast cancer, taking into account the number of HER2-amplified CTC detected (1-4 or 5+).

Statistical methods: To design this adaptive study, response rates were estimated to be H0 = 5% (no efficacy of T-DM1) and H1 = 25% (efficacy of T-DM1). After the first step (N = 7L and 7H patients): if no response is seen, the trial will be stopped, and considered as negative; if 3 or more responses are seen, we will conclude that the CTC FISH test is relevant to select patient for T-DM1 treatment, in either the L or/and H population, according to the observed pattern of responses; if 1 or 2 responses are observed, 14 more patients will be enrolled (7L+7H) in the second step of the trial. At the end of the second step, if 3 or less responses are observed, the trial will be considered as negative; if 4 or more responses are seen, we will conclude that the CTC FISH test is relevant to select patient for T-DM1 treatment, in either the L or/and H population, according to the observed pattern of responses. Based on the above-mentioned hypotheses and number of patients, the alpha risk was simulated to be of 6%, with a power of 94%.

Present accrual and target accrual: trial will start in summer 2013 in France. Up to 28 patients will be treated in this study.

Contact information: Francois-Clement Bidard, Institut Curie, Paris, France.

Citation Information: Cancer Res 2013;73(24 Suppl): Abstract nr OT1-1-10.

Inception and validation of a pressure ulcer risk scale in oncology

OBJECTIVE

To create and validate a specific tool to evaluate the pressure ulcer risk in cancer patients.

METHOD

The Pressure Ulcer Scale in Oncology (PUSO) was developed and subsequently validated against the Norton and Braden scales in order to efficiently and reliably evaluate the pressure ulcer risk in adult cancer patients, with various sites and stages of the illness (both curative and palliative phases). Two series of prevalence surveys (three surveys over two days, at two-month intervals) were conducted in one and then two French Cancer Centres in 2002 and 2009, respectively. The surveys investigated a total of 933 patients.

RESULTS

Multivariate logistic regression analysis identified three key items as being predictive of the development of pressure ulcers in cancer patients (mobility, incontinence and moisture/shearing), all with similar odds ratio weighting. A score was defined using this logistic model, the PUSO score (0-3)=bedridden/chair-ridden + incontinence + moisture/shearing.

CONCLUSION

The extreme simplicity of this scale may appear disconcerting, but the PUSO is a simple, reliable and validated tool, which allows standardised evaluation of each patient's risk and, thereby, rapid introduction of appropriate measures.

Identification of three-genomic regions prognostic signature in small node-negative breast carcinomas

Abstract #1081

Background: The purpose of this study was to identify a genomic signature of early metastatic recurrence, in order to predict accurately breast carcinomas clinical outcome and to select patients with node negative and small tumor size (<3cm) who would benefit from adjuvant chemotherapy.
 Patients and methods: Using genome-wide BAC-PAC Genomic Comparative Hybridization (CGH) array (1kb), we analyzed a training set of 78 patients. All patients had invasive ductal carcinomas and were initially treated by surgery and radiotherapy, without chemotherapy. The validation was performed on an independent test set of 90 patients. The training and tests sets were composed of respectively 53 and 58 patients disease-free survivors at 60 months (good prognosis group), and by 25 and 32 patients with distant metastatic recurrence before 48 months (poor prognosis group). In the training set, a signature was established as a logistic multivariate model of regions containing contiguous BAC clones with statistically different ratios and median frequencies of gains and losses between the poor and the good prognosis groups. This signature was then validated using the independent test set to evaluate its accuracy to classify T0T1T2N0 patients according to their outcome.
 Results: The training test identified a prognostic signature defined by 3 genomic regions, located on the 2p (38.3 to 40.9Mb), 3p (32 to 80.3Mb), and 8q (78.8 to 128.9Mb) chromosomes. In the test set, 90% of patients of favourable outcome were ER +ve and 88% were PR +ve, compared to 62% and 55% in the poor outcome group, respectively. In the test set, our signature was highly informative to identify patients that developed distant metastases before 48 months: the rate of patients well classified was 0.74, CI (95%): [0.64; 0.83], with a specificity of 95%, CI (95%): [86%; 99%]. On Kaplan-Meier analysis, the poor-prognosis genomic signature group of patients had a RR of 3.5 of metastatic relapse (log rank test p<0.001).
 Conclusions: Our signature, validated on an independent series of small T0T1T2N0 and on a majority of ER/PR positive tumors, may provide a robust and accurate tool to identify, in addition to classical parameters, patients who would benefit from adjuvant medical treatments. The comparison of this genomic signature with RNA based signatures and clinico-pathological parameters, is currently being investigated.

Citation Information: Cancer Res 2009;69(2 Suppl):Abstract nr 1081.

UVA radiation is highly mutagenic in cells that are unable to repair 7,8-dihydro-8-oxoguanine in Saccharomyces cerevisiae

UVA (320-400 nm) radiation constitutes >90% of the environmentally relevant solar UV radiation, and it has been proposed to have a role in skin cancer and aging. Because of the popularity of UVA tanning beds and prolonged periods of sunbathing, the potential deleterious effect of UVA has emerged as a source of concern for public health. Although generally accepted, the impact of DNA damage on the cytotoxic, mutagenic, and carcinogenic effect of UVA radiation remains unclear. In the present study, we investigated the sensitivity of a panel of yeast mutants affected in the processing of DNA damage to the lethal and mutagenic effect of UVA radiation. The data show that none of the major DNA repair pathways, such as base excision repair, nucleotide excision repair, homologous recombination, and postreplication repair, efficiently protect yeast from the lethal action of UVA radiation. In contrast, the results show that the Ogg1 DNA glycosylase efficiently prevents UVA-induced mutagenesis, suggesting the formation of oxidized guanine residues. Furthermore, sequence analysis of UVA-induced canavanine-resistant mutations reveals a bias in favor of GC-->TA events when compared with spontaneous or H(2)O(2)-, UVC-, and gamma-ray- induced canavanine-resistant mutations in the WT strain. Taken together, our data point out a major role of oxidative DNA damage, mostly 7,8-dihydro-8-oxoguanine, in the genotoxicity of UVA radiation in the yeast Saccharomyces cerevisiae. Therefore, the capacity of skin cells to repair 7,8-dihydro-8-oxoguanine may be a key parameter in the mutagenic and carcinogenic effect of UVA radiation in humans.

[New trends in assessment in anticancer treatments by phase II clinical trials]

The aim of phase II clinical trials in oncology is to judge if a new treatment have a sufficient antitumor activity to justify further studies. They represent a crucial step in a new anticancer therapy development. The aim is to present phase II clinical trials planification and interpretation methods, end points, recent methods and news in tumor response assessment. Changes of the place of phase II clinical trials in a new treatment development strategies are finally shown. Non randomized trials planification methods (unique analysis, Gehan's method, Simon's procedure, Fleming's multi-stages procedure, triangular test) are described. Usual primary end point is tumor size diminution. Some studies are interested in secondary end points like survival data or treatment toxicity. New planification methods are exposed : randomized phase II clinical trials, phase II within a phase III trial, cross-over studies and bayesian theories are presented. Recent tumor response evaluation theories ("Recist") are described. Phase II trials function in new treatment development is progressing : they could be sufficient, in some cases, to allow a temporary marketing authorization if a treatment show great efficacy. Global reflection upon new treatment and methods allowing marketing authorization is required.