FIG 4.

(A) Overall survival time of the PDX+ patients who relapsed, measured from the time of histologic diagnosis of relapse. (B) Overview of the characteristics and treatment timelines of tumors that relapsed, stratified by PDX engraftment. Time of recurrence was the interval between definitive surgery and histologic diagnosis of recurrence. Patients were treated per physician discretion. The two PDX+ patients for whom PDX-derived organoid-based drug profiling was performed on recurrence for informed treatment selection are highlighted in red boxes on the right. The first patient has been discussed elsewhere¹⁷; the second patient (marked with ^a) is shown in detail in (C). (C) Clinical course of a patient with PDX+ metaplastic breast cancer after development of recurrent (metastatic) disease (day 0) where treatment was informed by prospective genomic and PDX-derived organoid-based drug profiling studies. ER, estrogen receptor; HER2, human epidermal growth factor receptor 2; pCR, pathologic complete response; PDX, patient-derived xenograft; PDX+, successful engraftment; PDX–, no engraftment; RD, residual disease; TNBC, triple-negative breast cancer.