Activation of the mTORC1 pathway is commonly observed in ER+ breast cancer due to genetic (mutation of genes encoding receptor tyrosine kinases or downstream oncogenes, loss‐of‐function of tumor suppressor genes) or nongenetic factors (increased levels of extracellular growth factors, long‐term estrogen deprivation).31, 32. The gene discussed is NTRK1; the disease is neoplasm.