Clinical practice patterns for advanced breast cancer patients on CDK4/6 inhibitors receiving palliative radiation therapy.
Bibliographic record
Abstract
269 Background: Patients with hormone-receptor positive advanced breast cancer (ABC) often require palliative radiation therapy (RT) while receiving systemic treatment with CDK4/6 inhibitors (CDK4/6i). There are conflicting reports in the literature regarding whether concurrent administration of CDK4/6i and RT increases RT or hematologic toxicity and there are currently no formal guidelines for this realm. A Canadian national survey was conducted to evaluate local practice patterns of CDK4/6i management during palliative RT. Methods: An anonymized online survey was distributed to 162 Canadian breast cancer health care professionals between November 2020 and January 2021. The survey collected provider demographics and questions regarding practice, experiences and opinions on CDK4/6i management during palliative RT for ABC. Results: The survey was completed by 76 (47%) of the invited participants: 40% were medical oncologists, 26% radiation oncologists, 16% pharmacists and 18% nurses, physician assistants or radiation therapists. Nine provinces were represented. The respondents' clinical practice settings were predominantly at an academic/cancer centre (84%), while 16% of clinicians were based at a community setting. Interrupting the CDK4/6i during RT was recommended always by 21% of respondents, sometimes by 46% and never by 9%, while 24% had no opinion. The majority of opinions were based on personal experience (55%), colleagues’ practice (37%), medical literature (33%) and experience with chemotherapy agents (18%). Unexpected RT toxicity observed in patients on concomitant CDK4/6i was reported by 9% of respondents and prolonged cytopenias by 15%. Among responders who always or sometimes interrupt CDK4/6i during palliative RT, the timeframe to hold CDK4/6i prior to RT was 4-7 days 45%, 1-3 days 32%, 8-14 days 13% and 10% were unsure. Responses were similar for the timeframe used to resume the drug after RT. The majority (94%) thought that advising the patient on what to do with the CDK4/6i during RT was the role of the Medical Oncologist, while 48% also thought it was the role of the Radiation Oncologist. 23% of respondents though the patient should always be reassessed prior to restarting the CDK4/6i; 45% said sometimes, and 29% said not necessary. 82% of respondents indicated a standardized protocol or guideline would be valuable in this setting. Conclusions: Two thirds of Canadian breast cancer specialists sometimes or routinely interrupt CDK4/6i treatment during RT with 15% having observed increased toxicity with concurrent administration. Consensus guidelines for the management of CDK4/6i and RT are necessary to reduce treatment variability and improve the quality and safety of care for these patients.
Fetched live from OpenAlex and de-inverted. Abstracts are not stored in this database: the inverted indexes are 8.6 GB of the frame’s 9.3 GB of text, and the host has 13 GB free.
How this classification was reachedexpand
Full frame distilled prediction
Teacher imitationNot calibrated prevalence, not ground truth. Human validation pending. Learned from the 10,348 direct Codex labels and 10,348 direct Gemma labels. Candidate is the union of thresholded teacher heads; consensus is their intersection. These outputs are machine_predicted_unvalidated and are not human labels or direct frontier model labels.
Codex and Gemma teacher scores by category
| Category | Codex | Gemma |
|---|---|---|
| Metaresearch | 0.003 | 0.014 |
| Meta-epidemiology (narrow) | 0.000 | 0.000 |
| Meta-epidemiology (broad) | 0.002 | 0.001 |
| Bibliometrics | 0.000 | 0.000 |
| Science and technology studies | 0.000 | 0.000 |
| Scholarly communication | 0.000 | 0.000 |
| Open science | 0.000 | 0.000 |
| Research integrity | 0.000 | 0.001 |
| Insufficient payload (model declined to judge) | 0.000 | 0.000 |
Machine scores (provisional)
The two teacher heads of the student model, read on this work. A score orders the frame for review; it never asserts a category, and the validation status ships verbatim with every row.
Baseline scores from an immature model (maturity gate not passed, 7 training rounds). Scores rank; they never assert a category.
score_only:v0-immature-baseline · verbatim from the scoring run: score_only means the number may rank works, and no category label ships from itClassification
machine, unvalidatedMachine predicted; a candidate call from one teacher head, not a consensus.
How this classification was reached, model by model and score by score, is at the end of the page under "How this classification was reached".