Systematic Review of the First 40 Cases of ¹⁷⁷Lu-PSMA Therapy in the Treatment of Non-prostatic Cancer

The current systematic review aimed to collect and analyze all available published and unpublished cases in which prostate-specific membrane antigen (PSMA)-targeted radioligand therapy (¹⁷⁷Lu-PSMA) was used to treat non-prostatic cancer.

Literature search and evidence acquisition through contacts with organizations that use ¹⁷⁷Lu-PSMA were employed. PubMed/Medline, SCOPUS, and ScienceDirect searches were performed following PRISMA recommendations. The search strategy was to screen all articles describing ¹⁷⁷Lu-PSMA radioligand therapy published to date with the key word "¹⁷⁷Lu-PSMA". These articles were collected and screened for non-prostatic cancer cases. Quality assessment was performed using the GRADE criteria.

A total of 713 articles were screened, and the search revealed 15 eligible records. Forty patients with a mean age of 51.2±18.5 years were treated with ¹⁷⁷Lu-PSMA for non-prostatic cancer. Of them, 30 cases were published, and 10 were found in medical institution records. Cancers of the salivary glands were most often targeted (13/40), followed by various brain cancer types (8/40), and osteosarcoma (6/40). The authors used previously established protocols for castration-resistant prostate cancer with the dose per cycle as 6.0-7.4 GBq and the number of cycles between one and four. Toxicity was estimated as low, and 21 out of 28 patients with reported outcomes survived to the time of the publication.

PSMA-targeted radioligand therapy was infrequently used to treat different non-prostatic cancer types in various target organs. These pioneering efforts indicate that ¹⁷⁷Lu-PSMA can be used to treat non-prostatic cancer with PSMA expression. The toxicity of such treatment was low, and the outcome was relatively good.