An observational study in Breast Cancer, sponsored by Eastern Cooperative Oncology Group. Not yet recruiting. Open to female participants aged 18 Years and older. Per ClinicalTrials.gov, last updated 2025-05-30.
Sponsored by Eastern Cooperative Oncology Group · Observational
The purpose of this study is to retrieve tissue samples from individuals with breast cancer who previously enrolled on the PACCT-1 (TAILORx) or S1007 (RxPONDER) trials and experiences a recurrence of their cancer (Cohort 1, 2, and 3), and/or the tumor initially removed at surgery in patients previously enrolled in step 1 of S1007 (RxPONDER) and found to have a high Recurrence Score of 26-100 (Cohort 3) but not followed on the study after that point. The tissue will be used for future research designed to understand why breast cancer recurs despite hormonal therapy or chemotherapy plus hormonal therapy.
To collect tumor biospecimens from patients who previously enrolled in either TAILORx or RxPONDER. There are 3 separate cohorts separated by recurrence score and study:
These samples will be used to assess the following primary objectives:
The study team also plans to evaluate immune composition and the prevalence of tumor-immune microenvironment (TME subtypes), and characterize the TME and cell-cell interactions in native tissue context through spatial tanscriptomic and proteomic profiling of tissue sections.
14,825 studies on the registry are indexed under Breast Neoplasms; 3,319 are open to participants now.
This study's planned enrollment of 600 is above the median of 184 across 3,235 observational studies indexed under Breast Neoplasms.
Browse Breast Neoplasms studies →Eastern Cooperative Oncology Group is the lead sponsor of 175 studies on the registry; 7 are open to participants now.
Of its 10 completed or terminated interventional studies of FDA-regulated products, 5 (50%) have results posted.
Counted across the registry records on this site, refreshed daily.
Patients previously enrolled on TAILORx with a recurrence score (RS) 0-100_and RxPONDER with a recurrence score(RS) 0-25 and patients previously enrolled on RxPONDER with a recurrence score (RS) 26-100.
Patient must have met the criteria for 1 of the 3 possible cohorts described below:
Exclusion Criteria:
Underlined terms in the criteria open these too. Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
A biopsy takes a small piece of tissue to examine. “Archival tissue” is a sample already taken, for example at diagnosis, and kept by the hospital.
Whether a stored sample will do depends on when it was taken, how much there is and what the study needs. Ask whether the study accepts your stored sample or needs a new biopsy.
Before you join, the study team explains what taking part involves — its purpose, what happens, the risks and possible benefits — and answers your questions, so you can decide freely. Consent is usually recorded on a form (the informed consent form, ICF) signed by you or, where the law allows, by someone legally authorised to decide for you.
You can keep asking questions during the study, you are told of new information that matters, and you can choose to leave at any time.
A scale of how much an illness limits everyday activity. For people being assessed to join a study, scores run from 0 (fully active) to 4; lower is more active.
Studies most often ask for 0–1 or 0–2. Your doctor gives the score; the WHO scale uses the same steps. The full scale also has 5, which records death.
Biopsy and archival tissue
A biopsy takes a small piece of tissue to examine. “Archival tissue” is a sample already taken, for example at diagnosis, and kept by the hospital.
Whether a stored sample will do depends on when it was taken, how much there is and what the study needs. Ask whether the study accepts your stored sample or needs a new biopsy.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Informed consent
Before you join, the study team explains what taking part involves — its purpose, what happens, the risks and possible benefits — and answers your questions, so you can decide freely. Consent is usually recorded on a form (the informed consent form, ICF) signed by you or, where the law allows, by someone legally authorised to decide for you.
You can keep asking questions during the study, you are told of new information that matters, and you can choose to leave at any time.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
ECOG performance status
A scale of how much an illness limits everyday activity. For people being assessed to join a study, scores run from 0 (fully active) to 4; lower is more active.
Studies most often ask for 0–1 or 0–2. Your doctor gives the score; the WHO scale uses the same steps. The full scale also has 5, which records death.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Previously enrolled on TAILORx with recurrence score (RS) 0-100 AND had a biopsy-confirmed locoregional, distant, or both locoregional and distant recurrence prior to registration on EA1241.
Previously enrolled on Step 2 of RxPONDER with recurrence score (RS) 0-25 AND had a biopsy-confirmed locoregional, distant, or both locoregional and distant recurrence prior to registration on EA1241.
Previously enrolled on Step 1 of RxPONDER and found to have a high Oncotype DX Recurrence Score (RS) 26-100.
Patterns of clonal evolution
Conditional logistic regression for matched pairs, with the recurrence sample representing the case and the baseline sample the non-case in each pair, will be used to test for differences between recurrence and baseline, to estimate odds ratios, and to jointly model effects. The test for association of a single binary factor in this approach is equivalent to McNemar's test.
Time frame: 2 years
Prevalence of the integrative cluster (IntClust) and intrinsic (PAM50) subtypes
Conditional logistic regression for matched pairs, with the recurrence sample representing the case and the baseline sample the non-case in each pair, will be used to test for differences between recurrence and baseline, to estimate odds ratios, and to jointly model effects. The test for association of a single binary factor in this approach is equivalent to McNemar's test.
Time frame: 2 years
Molecular signatures of primary tumor specimens
Conditional logistic regression for matched pairs, with the recurrence sample representing the case and the baseline sample the non-case in each pair, will be used to test for differences between recurrence and baseline, to estimate odds ratios, and to jointly model effects. The test for association of a single binary factor in this approach is equivalent to McNemar's test.
Time frame: 2 years
Immune composition
Evaluated using weighted Cox models
Time frame: 2 years
TME and cell-cell interactions
Evaluated using weighted Cox models
Time frame: 2 years
Prevalence of IntClust and PAM50
Evaluated using weighted Cox models
Time frame: 2 years
Molecular signatures
Evaluated using weighted Cox models
Time frame: 2 years
No study locations are listed for this record.
This study is not yet recruiting, as verified in May 2025. You cannot join it, but the record below documents what was studied.
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