Peptide receptor radionuclide therapy (PRRT) and the pituitary: safety and efficacy.

Peptide receptor radionuclide therapy (PRRT) is an emerging and promising targeted treatment for aggressive pituitary neuroendocrine tumours (PitNETs) and pituitary carcinomas refractory to conventional therapies. Its use is supported by the frequent expression of somatostatin receptors (SSTRs), predominantly SSTR2, in pituitary tumour cells, enabling selective delivery of β-emitting radionuclides, such as 177Lu-DOTATATE and 90Y-DOTATOC, resulting in targeted antitumour and antisecretory effects. This narrative review summarises current limited evidence on PRRT efficacy and safety in aggressive pituitary tumours. Successful outcomes have been reported in some cases in terms of tumour growth reduction and/or hormonal reduction or relief of mass-effect-related symptoms. PRRT-related adverse events are mostly mild and transient, predominantly haematological, with clinically significant renal toxicity uncommon when amino acid nephroprotection is used. Preserved pituitary function and no clinically significant PRRT-induced hypopituitarism have been reported. Overall, PRRT represents a biologically rational and potentially effective option for selected patients with SSTR-positive aggressive PitNETs after failure of previous therapies.