The Safety and Efficacy of the Repeated PRRT with [⁹⁰Y]Y/[¹⁷⁷Lu]Lu-DOTATATE in Patients with NET

Figure 3

Example of the effect of the repeated tandem [⁹⁰Y]Y/[¹⁷⁷Lu]Lu-DOTATATE therapy: a 30-year-old man with a nonfunctional rectal G2 NET after surgery for primary tumours, with progression of the disease after 43 months. The [⁶⁸Ga]Ga-DOTATATE PET/CT carried out for qualification to the PRRT showed increased uptake (higher than in the liver) in multiple, disseminated metastases. The patient received the initial PRRT, repeated PRRT, and re-repeated PRRT with the total accumulated injection activity of 29.6 GBq. The PFS rate after the I-PRRT, R-PRRT, and RR-PRRT was 35, 19, and 13 months, respectively. The disease progression after each therapy course was observed in different parts of the body. (a) [⁶⁸Ga]Ga-DOTATATE PET MIP (maximum intensity projection) before the I-PRRT showing uptake in multiple metastases; (b) [⁶⁸Ga]Ga-DOTATATE PET MIP after the I-PRRT showing partial response to the treatment; and axial fusion [⁶⁸Ga]Ga-DOTATATE PET/CT (c, d) before and (e, f) after the I-PRRT. (g) [⁶⁸Ga]Ga-DOTATATE PET MIP before the R-PRRT showing progression of the disease after the I-PRRT; (h) [⁶⁸Ga]Ga-DOTATATE PET MIP after the R-PRRT showing partial response to the treatment; and axial fusion [⁶⁸Ga]Ga-DOTATATE PET/CT (i, j) before and (k, l) after the R-PRRT. (m) [⁶⁸Ga]Ga-DOTATATE PET MIP before the RR-PRRT showing progression of the disease after the R-PRRT; (n) [⁶⁸Ga]Ga-DOTATATE PET MIP after the RR-PRRT showing partial response to the treatment; and axial fusion [⁶⁸Ga]Ga-DOTATATE PET/CT (o, p) before and (q, r) after the RR-PRRT.