A literature review conducted by Cancer Care Ontario (CCO) [9] showed that PET-CT on stage III breast cancer had distant metastasis detection rates of 26%, 22%, and 32% across estrogen receptor-positive (ER+), HER2+ and TNBC subtypes respectively, whereas for stage II the detection rates were consistent at 10% across subtypes. The gene discussed is ESR1; the disease is breast carcinoma.