Background: Breast cancer survivors (BCSs) often face long‐term complications, with upper‐limb lymphedema and cancer‐related fatigue (CRF) being challenging. This study aimed to investigate the relationship between upper‐limb lymphedema and fatigue among BCSs.Method: This cross‐sectional study was performed on 102 BCSs, of which 31 (30.4%) had breast cancer–related lymphedema. Duration, stage, and excess volume were considered as indicators of breast cancer–related lymphedema severity. QoL was measured using the EORTC QLQ‐C30. The score of the fatigue symptom scale was used based on EORTC QLQ‐C30 for CRF assessment. Also, the brief fatigue inventory was used to measure the severity of fatigue among participants.Results: The mean fatigue symptom scale and brief fatigue inventory scores were 37.90 ± 24.59 and 3.69 ± 1.25, respectively. The mean fatigue symptom scale was significantly different among BCSs with BMI ≤ 25 and BMI > 25 (29.59 ± 24.49 vs. 41.51 ± 23.88, p = 0.026). Also, the mean brief fatigue inventory was significantly different among BCSs with the number of dissected lymph nodes (LNs) ≤ 5 and > 5 (3.52 ± 1.18 vs. 4.08 ± 1.34, p = 0.042). Additionally, women with breast cancer–related lymphedema had significantly higher scores of fatigue symptom scale and brief fatigue inventory (46.59 ± 27.12 vs. 34.11 ± 22.56, p = 0.03, and 4.75 ± 1.21 vs. 3.22 ± 0.96, p = 0.001, respectively). Except for a weak correlation between BMI and fatigue symptom scale and brief fatigue inventory (r: 0.279, p = 0.004, and r: 0.313, p = 0.001, respectively), there was no other significant relationship between CRF and study variables such as breast cancer–related lymphedema duration, stage, and excess volume. Meanwhile, fatigue symptom scale and brief fatigue inventory were significantly correlated with global health and functional scale scores of EORTC QLQ‐C30. The ROC curve which models the diagnostic efficacy for fatigue symptom scale showed an AUC of 0.634 (p = 0.034, 95% CI: 0.510–0.759), while the ROC curve which models the diagnostic efficacy for brief fatigue inventory showed an AUC of 0.821 (p < 0.001, 95% CI: 0.735–0.908).Conclusion: This study highlighted that while breast cancer–related lymphedema was associated with increased CRF, the severity of lymphedema did not significantly correlate with CRF. Additionally, CRF might be an indicator of breast cancer–related lymphedema among BCSs.
