“…More recently, a syngeneic model reported by Chen, Liu, et al (2019) developed both lymph node and lung metastases 8 weeks after the orthotopic implantation of cells derived from 4NQO‐induced OSCC (5 × 10 6 cells, MOC‐L1‐Luc murine cell subclone). However, the majority of developed orthotopic models of OSCC had no or very few lung metastases, probably due to the fast growth of the primary tumor and/or a high number of injected OSCC cells (e.g., 0.2–5 × 10 6 ) accompanied by an early sacrifice of the animals (3–3.5 weeks) (Chen, Chang, Yang, Tu, & Lin, 2019; Matsui et al., 1998; Noguchi et al., 2003; Umeda et al., 2001).…”