Table 2 Targeted internal radiotherapy: schedules and adverse effects

Low specific activity [¹³¹I]MIBG

High dose (>444 MBq/kg), meta-analysis^144,147,191

87% grade 3–4 neutropenia (required growth factor), 83% grade 3–4 thrombocytopenia (required platelet transfusion), myelodysplastic syndrome (4%) (especially together with chemotherapy), hypothyroidism (11–20%), acute respiratory distress syndrome, bronchiolitis obliterans, hypertension, hypogonadism (6.8%); rarely: renal failure, hypertensive crisis (despite α-adrenoceptor blockade), hepatotoxicity; constitutional symptoms, that is, nausea and vomiting

Low specific activity [¹³¹I]MIBG

Low–intermediate dose (<9.25 GBq total dose, often repeated)^147,191

Myelodysplasia (7%), hypothyroidism (11–20%), hypogonadism, myelotoxicity (<19%) grade 3–4; constitutional symptoms are common

High specific activity [¹³¹I]MIBG (Azedra)

High dose (~18.5 GBq, usually ×2)^141,147

Severe and long-term myelosuppression as indicated by haematological adverse effects in 90% of patients, with grade 3–4 adverse effects in 72% of patients, 25% required haematological supportive care, 19% serious adverse effects related to haematological toxicity, 3% lung embolism, 4% myelodysplastic syndrome, 1.5% AML, 1.5% ALL, 3.4% hypothyroidism, 11% worsening hypertension within 24 h, 7% kidney failure or acute renal injury; constitutional symptoms, that is, nausea 76%, all grades

[¹⁷⁷Lu]DOTATATE

Typically, 7.4 GBq four times¹⁴⁷

Adverse events in one meta-analysis (n = 234)¹⁹¹: 1.4–2.2% myelodysplastic syndrome, 0–1.5% nephrotoxicity, 9.5–11.3% haematological toxicity, all grade 3–4; in another meta-analysis (n = 201)¹⁴⁵: 4% nephrotoxicity, 3% neutropenia, 9% thrombocytopenia, 11% lymphopenia, all grade 3–4; constitutional symptoms, that is, 65% nausea and 53% vomiting, of all grades, commonly related to amino acid pretreatment, 3% renal failure, grade 3–4; incidence for PRRT-related myelodysplastic syndrome 2.5–8.3%