There was no correlation between the SUVmax obtained from 68Ga-Pentixafor and PET molecular subtypes, estrogen receptor (ER), progesterone receptor (PR) or human epidermal growth factor receptor 2 (HER2) status; however, triple-negative breast cancers had more avid 68Ga-Pentixafor accumulation compared to luminals A and B. The median (Q1–Q3) 68Ga-Pentixafor TLU was significantly higher in HIV-positive (376 (219–881)) compared to HIV-negative (174 (105–557)) breast cancer patients. This evidence concerns the gene ESR1 and breast cancer.