Lapatinib Resistance in Patients With Breast Cancer

Study of Resistance Mechanisms Against Lapatinib in Patients With ErbB-2-Positive Breast Cancers

Status

Withdrawn

Phases

Unknown

Study type

Observational

Source

ClinicalTrials.gov

Registry ID

NCT00898573

Enrollment

Registered

2009-05-12

Start date

2008-07-31

Completion date

Unknown

Last updated

2015-10-02

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

Breast Cancer

Keywords

breast cancer

Brief summary

RATIONALE: Studying samples of tumor tissue and blood from patients with cancer in the laboratory may help doctors learn more about cancer and the development of drug resistance in patients. PURPOSE: This research study is looking at lapatinib resistance in patients with breast cancer.

Detailed description

OBJECTIVES: * To identify secondary ErbB2 mutations in tumor tissue samples from patients with ErbB2-positive breast cancer treated with lapatinib ditosylate. * To investigate ErbB2 copy number changes and expression levels. * To determine abnormalities of other pathways (e.g., c-MET and PI3K) as potential mechanisms of resistance. OUTLINE: Previously collected tumor tissue samples\* are obtained for genetic analysis studies. Samples are analyzed for secondary ErbB2 mutations by nested PCR; ErbB2 copy number changes by quantitative PCR and standard histological FISH; and ErbB2 expression levels by quantitative RT-PCR and IHC. Patients also undergo blood sample collection for extraction of DNA (as normal control DNA) and isolation of EpCAM-positive circulating tumor cells using immunomagnetic cell separation technology. Additional research studies may include mutational and amplification analysis of the c-MET and PI3K pathways. NOTE: \*Patients may undergo biopsy if a post-treatment tumor tissue sample is unavailable.

Interventions

DRUGlapatinib ditosylate

GENETICfluorescence in situ hybridization

GENETICgene expression analysis

GENETICmutation analysis

GENETICpolymerase chain reaction

GENETICreverse transcriptase-polymerase chain reaction

OTHERcell sorting

OTHERimmunohistochemistry staining method

OTHERlaboratory biomarker analysis

Study design

Observational model

CASE_ONLY

Time perspective

CROSS_SECTIONAL

Eligibility

Sex/Gender

ALL

Healthy volunteers

Inclusion criteria

DISEASE CHARACTERISTICS: * Pathologically confirmed invasive breast cancer * ErbB2-positive disease * Has received or is currently receiving lapatinib ditosylate * Documented clinical benefit while receiving lapatinib ditosylate (e.g., stable disease of ≥ 12 weeks duration OR a radiographic response) * Must have tumor tissue samples available for research studies * Hormone receptor status not specified PATIENT CHARACTERISTICS: * Menopausal status not specified * Not pregnant\* * Coagulation profile normal\* * Platelet count \> 100,000/mm³\* NOTE: \*For patients requiring a post-treatment biopsy PRIOR CONCURRENT THERAPY: * See Disease Characteristics * Concurrent chemotherapy or trastuzumab (Herceptin®) allowed * No concurrent anticoagulants, including warfarin or low-molecular weight heparin\* * No concurrent antiplatelet therapy, including aspirin, clopidogrel, or other antiplatelet agents\* NOTE: \*For patients requiring a post-treatment biopsy

Design outcomes

Primary

Measure	Time frame
Secondary ErbB2 mutations	—
ErbB2 copy number changes and expression levels	—
Abnormalities of other pathways (e.g., c-MET and PI3K) as potential mechanisms of resistance	—

Countries

United States

Outcome results

None listed

Source: ClinicalTrials.gov · Data processed: Feb 4, 2026