FIG 3.

(A) The log CSF CTC count relative to baseline for each subject is shown over time for IFRT (red) and pCSI (blue). Patients who only had baseline CSF CTC counts are not shown. (B) Estimated effect of treatment on CSF CTC count assessed through joint modeling of longitudinal and survival outcomes with shared random effects and an unspecified baseline risk function.²³ From the linear mixed-model component of the joint model of overall survival, we reported the slope from a nonsignificant interaction between histology and treatment arm. Although pCSI was associated with a decreasing CTC count after treatment, increasing CTC count was observed after IFRT. CTC, circulating tumor cell; IFRT, involved-field radiotherapy; NSCLC, non–small-cell lung cancer; pCSI, proton craniospinal irradiation.