Health & Medicine1 day ago

Trial reports 40% complete response with added drugs in high-risk rectal cancer

A single-center phase II study examined personalized treatment before surgery, but longer-term and comparative results are not provided.

Moderate evidenceHuman studyInterpret with caution

Medical disclaimer: This article summarizes research findings and is for informational purposes only. It is not medical advice.

Abstract editorial illustration accompanying the article: Trial reports 40% complete response with added drugs in high-risk rectal cancer — Editorial illustration — not from the study.

The TRAINER study examined total neoadjuvant therapy, meaning treatment given before possible surgery, in people with high-risk locally advanced rectal cancer. Participants received chemotherapy, followed by short-course radiation and more chemotherapy. One cohort received bevacizumab, while another received cetuximab as an added targeted drug.

What was studied

This was a multicohort, single-center, phase II clinical trial conducted from April 2021 through October 2024. It included 96 people with high-risk locally advanced rectal cancer. The regimen consisted of four cycles of modified FOLFOX6 chemotherapy, short-course radiation of 25 Gy in five treatments, and two additional cycles of modified FOLFOX6. Cohort B received bevacizumab, and cohort C received cetuximab during parts of the regimen. The main outcome was complete response, defined as either a sustained clinical complete response without detectable disease on clinical assessment or a pathological complete response found after surgery.

What the study found

Ninety of the 96 participants completed the prescribed treatment. A complete response was reported in 36 participants, or 40% of the study population described in the abstract: 18 in cohort B and 18 in cohort C. No grade IV or V toxicity was observed, although adverse effects linked to the targeted drugs occurred in three people in cohort B and 41 in cohort C. Curative surgery was performed in 43 people in cohort B and 38 in cohort C. Among those who had surgery, the reported sphincter-preservation rates were 90.7% and 89.5%, respectively. Postoperative complications occurred in seven people in cohort B and five in cohort C; one person in cohort C required another operation. The abstract lists survival as a secondary outcome but does not report survival results.

Where this may apply

The findings may be relevant to people with high-risk, locally advanced rectal cancer who are similar to the participants enrolled at this study center. They should not be assumed to apply to people with other stages or types of rectal cancer, different health conditions, or different treatment settings. The study does not establish that this regimen is appropriate for any individual, and its results do not show how it compares with standard or alternative treatments.

Why it matters

These findings provide early human data on a treatment strategy intended to produce a complete response before surgery in a higher-risk rectal cancer population. The reported response and surgery outcomes may help guide further research, but the study alone cannot show that the regimen is more effective or safer than other treatment approaches. The abstract does not provide the longer-term cancer-control results needed to assess durability.

Limitations & evidence assessment

The study was conducted at a single center, included a relatively small number of participants, and the abstract does not describe randomization or a comparison group. Without a control group, differences from other treatment strategies cannot be reliably attributed to this regimen. The abstract provides no follow-up duration or survival results, and it gives limited detail about how participants were assigned to cohorts or how complete responses were confirmed. Because only abstract-level information is available, additional details about participant selection, outcomes, and adverse effects are unknown.

Why this evidence level: Clinical trial without confirmed randomization details in the available metadata.

Evidence levels are editorial estimates derived from study metadata — they are not clinical appraisals.