CCTG CO.28 primary endpoint analysis: Neoadjuvant chemotherapy, excision and observation for early rectal cancer, the NEO trial.
Bibliographic record
Abstract
3508 Background: CO.28 (NCT03259035) is a phase II study designed to determine if patients with cT1-T3a/bN0 rectal cancer can be treated with induction chemotherapy (FOLFOX/CAPOX) and organ-preserving surgery. Methods: Patients with MRI staged cT1-3a/bN0 tumors and no pathologic (p) high risk features received 6/4 cycles of FOLFOX/CAPOX, repeat sigmoidoscopy/pelvic MRI and subsequent Transanal Endoscopic Surgery (TES) in the absence of tumor progression. ypT0/T1N0 tumors were treated with observation while ypT2+ or ypN+ stage were recommended Total Mesorectal Excision (TME). The primary endpoint was protocol specified Organ Preservation Rate (psOPR = ypT0/T1N0, no p high risk features) and actual Organ Preservation Rate (aOPR = ypT0/T1N0 stage plus higher yp stage patients who declined TME surgery). The study would be considered negative with an psOPR of 50% or lower (H0) and as promising if it is 65% or higher (H1). Results: Between 08/2017 to 05/2020, 58 eligible patients were accrued in Canada and the United States, median age was 67 years, 71% male. All had well-moderately differentiated, non-mucinous rectal adenocarcinoma and median tumor height was 6 cm (range 0-18). Median follow-up was 15.4 months. Chemotherapy with FOLFOX (32) or CAPOX (26) was administered, 90% completed all planned cycles. A total of 56/58 (97%) proceeded to TES, while one patient was ineligible due to tumor progression (1.7%) and one declined. In the intention to treat analysis, the psOPR was 57% (95% CI 43-70%) while the aOPR was 79% (95% CI 67% to 89%) due to 13/23 declining recommended TME surgery. Of 10 patients who proceeded to recommended TME, a complete R0 TME was performed in 9/10, and no p residual carcinoma was found in 7/10. Crude loco-regional (LR) and distant recurrence rates were 3.5% (95% CI 0.4 to 12%) and 0%, respectively. A recurrence occurred in 1/13 patients who initially declined TME surgery. Conclusions: In select patients with early stage rectal cancer, three months of induction CAPOX/FOLFOX followed by TES resulted in a high OPR without the use of pelvic irradiation. The observed high rate of pathologic downstaging may point to high chemo-responsiveness in early rectal adenocarcinoma with no p high risk features. Further trials to evaluate this approach are justified and updated results will be presented. Clinical trial information: NCT03259035. [Table: see text]
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 machine prediction
Teacher imitationNot calibrated prevalence, not ground truth. Human validation pending. The Gemma side is a direct model label for every work in the frame, read from the title-only record. The Codex side is a classifier learned from the 10,348 direct Codex labels and calibrated to design-weighted sample rates; fields without enough sample support carry no Codex call. Candidate is the union of the two sides; consensus is their intersection. These outputs are machine_predicted_unvalidated and are not human labels.
Distilled classifier scores by category (both heads)
| Category | Codex | Gemma |
|---|---|---|
| Metaresearch | 0.001 | 0.001 |
| Meta-epidemiology (narrow) | 0.001 | 0.000 |
| Meta-epidemiology (broad) | 0.001 | 0.001 |
| Bibliometrics | 0.000 | 0.000 |
| Science and technology studies | 0.000 | 0.000 |
| Scholarly communication | 0.001 | 0.000 |
| Open science | 0.000 | 0.000 |
| Research integrity | 0.001 | 0.002 |
| Insufficient payload (model declined to judge) | 0.007 | 0.001 |
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 source (direct Gemma or distilled Codex), 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".