A multi-centre, single arm, phase 2 trial of pembrolizumab in treatment-naïve patients with carcinoma of unknown primary site.
Bibliographic record
Abstract
2659 Background: Cancer of unknown primary (CUP) represents a heterogeneous group of cancers that present with metastatic epithelial disease with no identifiable primary lesion at the time of diagnosis. Patients with poor prognostic features have limited effective systemic therapy options. Researchers hypothesize that these primary lesions are occult, in part, due to anti-cancer immune surveillance. We hypothesize, pembrolizumab will have activity in this setting. Methods: This single arm phase 2 study evaluated the use of pembrolizumab in treatment naïve patients with poor prognosis CUP. Patients ≥18 years of age with ECOG PS 0-1 and histologically proven, measurable metastatic carcinoma with no primary site identified were eligible. Pembrolizumab was administered at 200 mg intravenously every 3-weeks for up to 24 months. The primary endpoint was safety and objective response rate (ORR) per RECIST 1.1. Secondary objectives included progression free survival (PFS) and overall survival (OS). The study used a Simon’s two stage design based on a one-sided test with a type 1 error rate of 0.1, null hypothesis for ORR ≤ 20% yielding a power of 0.8 with an alternate hypothesis of ≥40%. The null hypothesis will be rejected if 8 or more responses are observed in 25 patients. Mismatch repair (MMR) and microsatellite instability (MSI) testing was not mandatory for patients. Results: There were 27 evaluable and 6 unevaluable (no response assessment, included in adverse event analysis) patients. The median age was 64 (range 21-80) and the majority were male (57.6%) and ECOG 1 (84.8%). Four patients experienced grade 3 treatment related adverse events (pain, anorexia, fatigue, confusion, and anemia). There were no treatment related deaths or new signals of toxicity. Of the evaluable patients, the ORR was 18.5% (4 partial responses and 1 complete response), disease control rate was 51.9% (9 stable disease) and thus the null hypothesis could not be rejected. For evaluable patients, the median PFS and OS were 2.56 (95% CI 2.10 – 7.46) and 9.79 (95% CI 3.84 – 16.03) months respectively. The one patient who developed a CR had MMR deficiency and has completed 2 years of therapy. Of the 4 patients with a partial response, one had an MMR proficient tumour, while the remaining 3 had unknown MMR status. Conclusions: Although not meeting the primary endpoint, pembrolizumab has some activity in CUP patients. Patients with CUP should be screened for MMR or MSI. Future studies should evaluate combination therapies with the addition of pembrolizumab. Clinical trial information: NCT03391973 .
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 | 0.001 | 0.000 |
| 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 | 0.000 |
| 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".