Figure 3

(A) Survival comparison between breast cancer (BC) patients who developed secondary esophageal cancer(SEC) after radiation therapy (RT) and BC patients who developed SEC after no RT (before PSM); (B) survival comparison between BC patients who developed SEC after RT and BC patients who developed BC after no RT(after PSM); (C) survival comparison between BC patients who developed SEC after RT and patients with only primary esophageal cancer (OPEC); (D) Survival comparison between BC patients who developed SEC after no RT and patients with OPEC. (B) PSM matched BC patients who developed SEC after RT and BC patients who developed SEC after no RT at a 1:1 ratio. SEC patients with RT (C) and without RT (D) were matched with OPEC patients based on propensity scores at a ratio of 1:5, and survival analysis was performed. The variables that were matched for PSM were age at SEC diagnosis, year of SEC diagnosis, race, SEC stage, and type of SEC treatment. The Supplementary Data reveal the complete patient characteristics of OPEC before and after PSM. RT radiation therapy; no RT no radiation therapy; SEC secondary esophageal cancer; OPEC only primary esophageal cancer; OS overall survival.