BACKGROUND: Diagnosis of post-breast cancer lymphoedema is difficult because of inconsistent measurement approaches, measurement reliability and validity, and lymphoedema definition and criterion. AIMS: To examine lymphoedema occurrence using a body mass index (BMI)-adjusted limb volume change (LVC) as a potentially sensitive alternative criterion for assessment and diagnosis of lymphoedema. Secondary aims were to examine the risk of lymphoedema occurrence in relation to post-operative swelling and limb dominance and the cancer-affected side. METHODS: The volume calculated from circumferences of 193 breast cancer survivors was used to analyse lymphoedema assessment. A change ≥5% in affected-arm volume over percent change in BMI in comparison to pre-operative baseline was considered indicative of lymphoedema. RESULTS: For all participants, 63% met the 5% BMI-adjusted LVC criterion. Dominant limb and cancer-affected side were significantly related to lymphoedema occurrence only in those whose BMI ≥30 (p=0.02), while post-operative swelling significantly increased the lymphoedema risk irrespective of BMI (p=0.01). CONCLUSIONS: The proposed 5% BMI-adjusted LVC criterion provides a more sensitive estimation of post-breast cancer lymphoedema occurrence.