Patient-Derived Xenograft: An Adjuvant Technology for the Treatment of Metastatic Disease.

The occurrence of metastases severely affects prognosis for patients with cancer, making metastatic disease a daily societal challenge. Because of resistance to drugs, the potential curability with chemotherapy at the metastatic stage remains low. Large genomic analyses to identify new targets have their limitations due to intratumor heterogeneity when they are performed on tumor samples from primary tumors and because the functional value of molecular abnormalities in a cancer is usually not known. Additional tools are thus required for the development of new anticancer agents. The use of preclinical models is a key component of translational research in oncology. For four decades, xenograft models of human cancer cell lines injected subcutaneously in immunocompromised mice have been widely used, with disappointing results for predicting the clinical benefit of a new drug. Patient-derived xenografts are preclinical models rediscovered as innovative pharmacological tools, both for the preclinical development of anticancer drugs and as individual models for personalized treatment of metastatic disease. Here, we review the recent progress reported using patient-derived xenografts for the treatment of metastatic disease, and discuss the feasibility of their implementation in daily oncological care.