EAU 2023: LuTectomy: A Prospective Study of Dosimetry, Safety and Potential Benefit of Upfront 177Lu-PSMA-617 Radioligand Therapy Prior to Radical Prostatectomy in Men with High-Risk Localized Prostate Cancer

(UroToday.com) The 2023 EAU annual meeting included a game changing session, featuring a presentation by Dr. Renu Eapen discussing LuTectomy, a prospective study of dosimetry, safety, and potential benefit of upfront 177Lu-PSMA-617 radioligand therapy prior to radical prostatectomy in men with high-risk localized prostate cancer. Although 177Lu-PSMA-617 is approved in advanced mCRPC, perhaps Lutetium PSMA is a viable upfront treatment option:


LuTectomy is a prospective phase I/II study of 177Lu-PSMA-617 prior to surgery. Participants must have high risk prostate cancer (ie. PSA > 20 ng/mL, ISUP grade group 3-5, cT2 or higher, N1 disease), no distant metastases, and high uptake SUVmax >20 on PSMA PET. 20 men received 5 GBq of 177Lu-PSMA-617, followed six weeks later by radical prostatectomy + pelvic lymph node dissection. The primary outcome for LuTectomy was dosimetry (absorbed radiation dose). The trial design for LuTectomy is as follows:

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Among 20 men included in the trial, the median age was 66 years (IQR 61-69), median PSA was 18 ng/mL (IQR 11-35), 50% were grade group 4 or 5, 30% were cN1, and the median SUVmax was 31 (26-36):


The primary endpoint of absorbed radiation dose was as follows:

  • Prostate: Median 19.6 Gy (IQR 11.3-48.4)
  • Nodes: Median 37.9 Gy (IQR 33.1-50.1)
  • All lesions: Median 35.5 Gy (IQR 19.5-50.1)

Key secondary endpoints included safety and surgery. 177Lu-PSMA-617 was very well tolerated:

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And surgery was deemed to be safe and straightforward: 

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Another key secondary endpoint was imaging response, with 55% having a partial response, 40% having stable disease, and 5% of patients progressing during treatment:

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With regards to PSA response to 177Lu-PSMA-617, the median PSA reduction was 49% (IQR 32-67) and the PSA50 response rate was 45%:

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At a median follow-up of 13.8 months, the biochemical recurrence free survival was 80%. For histological response, 80% had a partial response, 15% had no response, 5% had minimal residual disease, and no patients had complete pathologic response. Dr. Eapen notes that indicators of response included:

  • Areas of stromal fibrosis
  • Reduced tumor cell density
  • Cytoplasmic vacuolation, gland atrophy
  • Extracellular mucin deposition 

By way of case presentation, LuTectomy patient #13 presented with a PSA of 30 ng/mL, received his 177Lu-PSMA-617 treatment, underwent robotic prostatectomy, and currently has a PSA of 0.01:

lutectomy 13.jpg 

Dr. Eapen concluded her presentation discussing results from LuTectomy with the following take-home messages:

  • 177Lu-PSMA-617 + surgery is safe and effective
  • Radiation dose delivery is high and targeted, but variable
  • There were encouraging biochemical, imaging, and pathologic responses
  • Further research in this disease space is worthwhile

Presented by: Renu S. Eapen, Peter MacCallum Cancer Centre, Melbourne, Australia

Written by: Zachary Klaassen, MD, MSc – Urologic Oncologist, Assistant Professor of Urology, Georgia Cancer Center, Augusta University/Medical College of Georgia, @zklaassen_md on Twitter during the 2023 European Association of Urology (EAU) Annual Meeting, Milan, IT, Fri, Mar 10 – Mon, Mar 13, 2023.