Longitudinal Changes in QTc Interval in Cancer Patients After the Initiation of Systemic Therapy: Analysis of the ONCOECHO Study Cohort

Figure 1. Boxplots of QT and QTcF intervals over time. Panel (A)—Boxplots of QTc values calculated using Fridericia’s formula. Boxes represent the interquartile range (IQR), the central line indicates the median, and whiskers represent the minimum and maximum values. p = 0.0075 for the post hoc comparison between baseline and month 6. Panel (B)—Boxplots of QT values. Boxes represent the interquartile range (IQR), the central line indicates the median, and whiskers represent the minimum and maximum values. p = 0.0024 for the post hoc comparison between baseline and month 6. ** indicates p < 0.01.

Figure 2. Heatmap of mean QTcF interval across treatment groups/cancer groups at baseline, 3 months, 6 months, and 12 months. Four heatmaps display the average QTcF interval (ms) for major chemotherapy-related treatment groups over time. QTcF values are shown on a unified grayscale scale ranging from 250 to 550 ms. Treatment categories include anthracyclines, taxanes, alkylating agents, antimetabolites, platinum agents, tyrosine kinase inhibitors (TKIs), monoclonal antibodies, and corticosteroids. Cancer classifications were grouped as breast cancer, lymphomas and leukemias (combined category of lymphoproliferative malignancies and chronic myeloid leukemia), colorectal cancer, renal cell carcinoma, and others. This figure illustrates the longitudinal variation in QTcF intervals across treatment modalities and cancer types.