Aims: To determine whether nutritional risk, identified using the Malnutrition Screening Tool (MST), is associated with treatment deliverability and toxicity in participants enrolled in early-phase oncology clinical trials.
Methods: Retrospective cohort study of participants enrolled on early-phase trials at a single clinical trials unit between April 2025 and April 2026 who received ≥12 weeks of per protocol treatment and had anthropometric data available. Participants at risk of malnutrition were classified by applying the MST criteria after 12 weeks on study. The primary outcome was hospitalisation. Secondary outcomes included dose reduction, treatment delay, grade ≥3 toxicity, and dietitian referrals. Groups were compared using Fisher's exact test. Multivariable logistic regression examined the association between malnutrition risk and hospitalisation, adjusting for ECOG performance status (PS), age, primary tumour type, investigational product class, and disease progression at 12-weeks.
Results: One hundred participants were included, median age was 66 years (range 26 – 87) and 60% were ECOG PS 1. Forty-nine (49%) met criteria for malnutrition risk (MST ≥2). Hospitalisation occurred in 26/49 (53%) at-risk participants versus 15/51 (29%) not at risk (p=0.025), and grade ≥3 non-haematological toxicity in 24/49 (49%) versus 12/51 (24%) (p=0.012). Rates of dose reduction (43% vs. 26%, p=0.091); treatment delay (43% vs. 37%) and grade ≥3 haematological toxicity (41% vs. 43%) were similar between groups. In multivariable analysis, malnutrition risk remained independently associated with hospitalisation (adjusted OR 2.95, 95% CI 1.26–6.91, p=0.013); no covariate, including disease progression at 12-weeks, was independently associated. Dietitian referral was low in both groups (12% vs. 6%, p=0.313).
Conclusions: MST-defined malnutrition risk was common in early-phase trial participants and was independently associated with a three-fold risk of hospitalisation. Referrals to dietitians were uniformly low. Routine nutritional screening and the impact of dietitian referral or other interventions in early-phase trial participants warrants prospective evaluation.