br Complications br Thirteen patients suffered from
Thirteen patients suffered from surgery-related complica-tions during follow-up. Most of them were grade 1 according to Clavien-Dindo: lymphedema (n = 7), paresthesia at the upper thigh (n = 3), wound healing disorder (n = 1), and CY7-SE leakage with conservative management (n = 1). One patient developed hydronephrosis with urosepsis that
Table 2 – Intraoperative parameters, pathological results, and complication rates
Surgical time (min)
Estimated blood loss (ml)
Histology positive Histology negative
Pathological results a
PSMA-RGS positive 46
PSMA-RGS negative 12
Statistical performance of PSMA-RGS ex vivo measurements in correlation with histopathology b
Positive predictive value
Negative predictive value
Clavien-Dindo grade Patients (%)
3 pts: paresthesia (upper thigh)
1 pt: wound healing disorder (conservative management)
1 pt: bladder leakage (conservative management with catheterization)
3a 1 (3.2%) Urosepsis and hydronephrosis (DJ catheter insertion, antibiotic treatment)
95% CI = 95%-confidence interval; GEE = generalized estimating equation; IQR = interquartile range; PSMA-RGS = prostate-specific membrane antigen– radioguided surgery, rating by ex vivo gamma probe measurements; pt(s) = patient(s). a Of separate tissue specimens.
b GEE model to account for multiple measurements within one patient.
required DJ catheter insertion and antibiotic therapy. No adverse events related to the 99mTc-PSMA-I&S injection were observed.
3.3. Short-term outcome
PSA follow-up was available in 30 patients. One patient received postoperative salvage-radiation therapy without prior PSA measurement. Compared with preoperative baseline, 24 (80%) and 17 (57%) patients showed 50% and 90% PSA decline, respectively (Fig. 2A). In 20 (67%) patients, a PSA decline below 0.2 ng/ml after 99mTc-PSMA-RGS was achieved. Seventeen of 30 (57%) patients showed an incomplete PSA response (PSA > 0.2 ng/ml) or rising PSA values >0.2 ng/ml during follow-up after a median of 1.9 mo. PSA value remained below 0.2 ng/ml without additional PC-specific treatment in 13 (43%) patients after a median follow-up of 13.8 mo (Fig. 2B). Eleven of 31 (35%) patients received additional PC-specific therapies after a median of 3.7 mo. The remaining 20 (65%) patients continued to be treatment free after a median of 12.2 mo (Fig. 2C). Median time for treatment-free survival was not reached yet.
The introduction of PSMA-targeting PET imaging has led to substantially improved visualization of small tumor deposits in patients with biochemically recurrent PC [7,8,17]. In
parallel, salvage surgery has gained increasing interest in patients with locoregional oligometastatic disease to posi-tively influence disease progression and delay the need for further systemic treatment [18–20]. However, no consensus about the extent of LN dissection and the templates Footprinting need to be dissected during salvage procedures could yet be reached. Difficulties are the varying and often altered lymphatic drainage patterns after previous therapy, and the different extent of prior surgeries. Besides careful selection of suitable patients potentially profiting from salvage surgery approaches, reliable detection and removal of metastatic soft tissue lesions are of utmost importance.
Here, we demonstrate the feasibility of 99mTc-PSMA-RGS to guide the intraoperative identification and surgical removal of metastatic LNs in PC patients scheduled for salvage surgery. The surgical technique proved especially useful to identify and excise small and/or atypically localized lesions, as depicted on preoperative PSMA PET. However, as patient selection is based on individual tumor-specific history and PSMA PET, the limited performance of PSMA PET for small metastatic lesions has to be acknowl-edged. As the detection rate is clearly size dependent (eg, >50% and >90% if short axis diameter equals or exceeds 2.3 and 4.5 mm, respectively ), careful dissection of surrounding tissue is mandatory to remove possible adjacent micrometastatic disease during RGS. Here, the sensitivity of 83.6% in our analysis reflects that even a negative gamma probe measurement cannot exclude small metastatic lesions completely.