Abstract

Title

Real time dynamic LDR Brachytherapy boost to external beam radiotherapy in prostate cancer

Authors

Samantha Forner1, Eunice Xing2, Saranya Ravindra1, Andrea D'Souza1, Frances Leach1, Sukhdeep Nagpal1, Teresa Guerrero Urbano 3, Vinod Mullassery 3, Oussama Elhage4, Rick Popert4, Stephen Morris1

Authors Affiliations

1Guy's Cancer Centre, Guy's and St Thomas' NHS Foundation Trust, Clinical Oncology, London, United Kingdom; 2Royal Free Hospital, Medicine, London, United Kingdom; 3Guy's Cancer Centre, Guy's and St Thomas' NHS Foundation Trust, Clinical Oncology , London, United Kingdom; 4Guy's and St Thomas' NHS Foundation Trust, Urology, London, United Kingdom

Purpose or Objective

Following the reports of the ASCENDE-RT trial we report a service evaluation of LDR brachytherapy as a boost to EBRT for patients with prostate cancer.

Materials and Methods

Retrospective review of patients treated with an LDR brachytherapy boost to EBRT between 2008 and 2018. LDR brachytherapy was carried out as a single stage day case procedure using a real time dynamic procedure prescribed to a dose of 110 – 115Gy, EBRT was delivered with IMRT and soft tissue matching IGRT to the prostate and SV +/- pelvic nodes to a dose of 46Gy/23#. We collected outcomes on overall survival and relapse. Late GU and GI Toxicity was scored using LentSoma. 

Results

139 patients were treated with Median age 64.  49 patients had high risk and 90 had intermediate risk disease.  49 patients received hormone therapy. Median follow-up of 52.4 months (range 3.5 to 129). The 5 year OS was 93.5%. The 5 year b-PFS was 84.4%. 9 patients have died, only 1 from prostate cancer. 14 patients have relapsed of which 6 biochemical relapse only, 6 lymph node and 2 bone metastases.  Late grade 3 GU toxicity incidence 6.5% (prevalence 2.2%), late grade 2 GI toxicity incidence 16.5%, grade 3  0.7%. 1 patient had a grade 4 recto-vesical fistula related to a rectal biopsy. Acute retention rate requiring catheterisation was 2.2%. The rate of urethral stricture requiring dilatation was 2.2%.

Conclusion

Our experience shows that the LDR brachytherapy as a boost to EBRT is highly effective and with modern brachytherapy techniques has a low incidence of toxicity.