Lutetium-PSMA has a favorable safety profile in locally advanced high-risk prostate cancer

The prospective open-label single-arm trial showed that all 11 lutetium-treated patients who underwent radical prostatectomy exhibited a biochemical response. Positive surgical margins were reported in 27% (3/11) of patients. By 3 months after surgery, all patients had recovered from continence.

“High-risk localized prostate cancer remains a therapeutic challenge,” said Frumer, a physician in the urology department at Rabin Medical Center in Petah Tikva, Israel. “The introduction of theranostics [has brought about] new treatment opportunities. Treatment with lutetium-PSMA is based on the ability of the PSMA ligand which is labeled with the 177-lutetium radioisotope to specifically bind to prostate cancer cells expressing PSMA to cause cellular damage. Recently, the efficacy of lutetium PSMA has been demonstrated in metastatic castration-resistant prostate cancer.

The study included a total of 12 patients with high-risk locally advanced prostate cancer, 7 with Gleason grade group (GGG) 4 disease and 5 with GGG 5 disease. administered two lutetium treatments of 7.4 GBq, one at 8 weeks before radical prostatectomy followed by pelvic lymph node dissection and one at 6 weeks before. The objective of the trial was to assess for the first time the safety and immediate oncologic outcome of lutetium PSMA followed by radical prostatectomy.

The median age of the population was 66 years (range, 60-68). The median baseline PSA was 11.4 ng / dL. Of the 12 patients who received lutetium-PSMA treatment, 11 underwent surgery.

Periprostatic adhesions were encountered during surgery without any intraoperative complications in 2 patients. The median duration of surgery was 220 minutes (range, 165-250), and the median estimated blood loss was 300 ml (IQR 200, 400). Median PSA levels decreased by 28% during treatment and the median hospital stay was 4 days (range: 3-4).

Regarding safety, the only adverse event (AE) reported during treatment was fatigue occurring in 2 patients. Investigators recorded no incidence of dry mouth or changes in blood count. Only one patient presented with postoperative fever. Treatment-related histological changes were noted in 4 of 6 final surgical specimens. No changes in blood count or dry mouth have been reported during treatment with lutetium-PSMA.

Postoperatively, pneumonia was reported in 1 patient. Another patient had a postoperative urine leak with conservative management.

“Neoadjuvant lutetium-PSMA followed by radical prostatectomy appears to be safe in patients with locally advanced high-risk prostate cancer,” Frumer concluded. “While longer oncology results are pending, recovery from continence does not appear to be affected by lutetium treatment. “

_Reference

_{Frumer M, Rosenbaum E, Kedar D, et al. MP15-20: 177Lu-PSMA-I&T neo-adjuvant radionuclide in high-risk prostate cancer before radical prostatectomy: a feasibility trial. Poster presented at the 2021 American Urological Association annual meeting, virtual. September 10-13, 2021. Summary MP15-20.}