Early Prostate Cancer Recurrence With PSMA PET Positive Unilateral Pelvic Lesion(s)

Significant advances in molecular nuclear medicine imaging in prostate cancer have been achieved in recent years. In particular, the introduction of prostate-specific membrane antigen (PSMA) -based tracers has significantly influenced diagnostic imaging of prostate. If cancer recurs after surgical removal of the prostate, targeted PSMA PET (positron emission tomography) can detect metastases even at very low PSA (prostate-specific Antigen) values. This increasingly allows individualized specific therapy of patients with prostate cancer recurrence. PSMA PET has now been included in national and international guidelines for the diagnosis of patients with biochemical recurrence of prostate cancer. Especially in patients in good general condition, with potentially longer life expectancy and early localized PSA recurrence, advances in molecular imaging are increasingly turning local therapy concepts into focus. Here both, radiotherapeutic (salvage radiotherapy of the lymphatic drainage) and surgical interventions (salvage lymph node dissection = removal of the pelvic lymph nodes) are offered on an individual basis. These regional therapies mainly aim to achieve a delay of further progression of the prostate cancer disease, and thus delay the initiation of palliative, sustained drug therapy. Previous standard or common practice at salvage lymph node dissection is the removal on both sides of the pelvic lymph nodes even if only one-sided suspicious lymph nodes are detected on imaging. Although the complications of salvage lymph node dissection are usually minor and manageable, they can still lead to impaired lymphatic drainage, leg edema, lymphocele formation or other surgical complications. The aim of the present study is to investigate whether a unilateral pelvic lymph node dissection on the side of conspicuous PSMA PET is sufficient and a dissection on the contralateral side can be dispensed without negatively impacting oncological outcomes and thereby sparing the patient the potential additional complications of a bilateral pelvic lymph node dissection.