EMUC16: Imaging and the treatment landscape for recurrent PCa

Current and prospective treatment strategies that employ image-guided approaches for prostate cancer recurrences were examined with experts exploring options in radiotherapy, surgery and chemotherapy.

Speakers Steven Joniau (BE), Barbara Jereczek-Fossa (IT), George Thalmann (CH) and Cora Sternberg (IT) presented various options in cases where prostate cancer (PCa) patients experienced castrate resistant or recurrent disease in the follow-up noon sessions in prostate cancer during the 8th European Meeting on Urological Cancers (EMUC16) held in Milan.

“Approximately 15% to 40% of men will go on to have recurrent disease following an attempt at curative therapy for PCa,” said Joniau as he introduced his presentation on the benefits of surgery.

He also noted that although there are novel PET-imaging techniques, these often only show the tip of the iceberg, limiting the definition of oligometastatic disease.

“Oligometastatic recurrence is often not curable with surgery as monotherapy. And the desired outcome of metastasis-directed therapy should mainly consist of delaying the natural course of the disease, causing few side effects,” said Joniau.

He said surgery is increasingly being considered in oligometastatic recurrence “as it is hypothesized that progression to CRPC may be delayed and survival may possibly be improved.”

“Surgery alone is often not enough to guarantee cure, therefore multimodal treatment may be the preferred approach,” he said.

Meanwhile, radiation oncologist Barbara Jereczek-Fossa discussed the role of ablative radiotherapy looking into when and how this option can be carried out in clinical practice. “Ablative radiotherapy has a different biology,” said Fossa as she noted that the procedure offers excellent local control (> than 90%) with minimal toxicity.

She added that with ablative RT there is a two to three-year progression free survival (PFS) of about 50% and more for intraprostatic failure.

“However, more investigation is warranted and we need to look into how to combine with systemic therapy,” she said.

Standing in for Rafael Sanchez-Salas, George Thalmann spoke on the role of focal therapy in treating cancer recurrence and provided a comprehensive overview on various imaging procedures, RT failure, salvage cryoablation, salvage brachytherapy, radiofrequency interstitial ablation (RITA) and nanoparticle thermotherapy, among other issues.

“Defining local recurrence after radiotherapy remains a difficult multi-task objective,” said Thalmann, and added that the goal of therapeutics is cancer control and reducing morbidity. “Multicentre collaboration is also essential,” he stressed.

Cora Sternberg discussed the role of image-guided approaches in the era of early chemotherapy, and said the issue is replete with challenges. She discussed Prostate-Specific Membrane Antigen (PSMA) in targeting PCa and noted its various characteristics and how they affect the treatment scenarios for resistant disease.

“PSMA PET/CT has high specificity and is valuable in planning therapy for patients with biochemical recurrence (BCR),” said Sternberg as she noted that novel radio-labelled tracers with PSMA ligand will be very useful.

She, however, cautioned that PSMA PET is not ready to be used to base decisions on chemotherapy on the finding of multiple small metastases, especially lymph nodes.