PSMA-positive nodal recurrence in prostate cancer : Salvage radiotherapy is superior to salvage lymph node dissection in retrospective analysis.

Abstract

PURPOSE:

This analysis compares salvage lymph node dissection (SLND) to salvage lymph node radiotherapy (SLNRT) of 68Ga-PSMA PET-positive nodal recurrences after radical prostatectomy (RPE).

METHODS:

A total of 67 SLNRT and 33 SLND consecutive patients with pelvic and/or para-aortic nodal recurrences after RPE were retrospectively analyzed. Biochemical recurrence-free survival rates (bRFS; PSA <0.2 ng/mL) were calculated according to Kaplan-Meier and survival curves were compared using the log rank test. For multivariable analysis, binary logistic regression analysis was performed (p < 0.05).

RESULTS:

Median follow-up was 17 months (range, 6-53 months) in SLND patients and 31 months (range, 3-56 months) in SLNRT patients (p = 0.027). SLNRT patients had significantly more tumours of pT3 and pT4 category (82% vs. 67%; p = 0.006), pathologically involved lymph nodes (45% vs. 27%; p = 0.001) and positive surgical margins (54% vs. 12%; p = 0.001) at time of RPE than SLND patients. PSA persistence after RPE was significantly more frequently observed in the SLNRT cohort (73% vs. 27%; p = 0.001). There was no significant difference in the distribution of PET-positive lymph nodes. Median PSA before SLND was higher than before SLNRT (3.07 ng/ml vs. 1.3 ng/ml; p = 0.393). The 2‑year bRFS was significantly higher in the SLNRT vs. the SLND cohort (92% vs. 30%; p = 0.001) with lower rates of distant metastases (21% vs. 52%; p = 0.002) and secondary treatments (5% vs. 39%; p = 0.011) irrespective of ongoing androgen deprivation therapy at last contact. In multivariable analysis, SLNRT was significantly associated with prolonged bRFS (regression coefficient 1.436, hazard ratio 4.204, 95% CI 1.789-9.878; p = 0.001).

CONCLUSION:

Based on this retrospective study SLNRT might be the preferred treatment option for patients with nodal recurrence after previous RPE.

• Authors: Nina-Sophie Schmidt-Hegemann, Alexander Buchner, Chukwuka Eze, Paul Rogowski, Christian Schaefer, Harun Ilhan, Minglun Li, Wolfgang Peter Fendler, Peter Bartenstein, Ute Ganswindt, Christian Stief, Claus Belka, Alexander Kretschmer
• Journal: Strahlentherapie und Onkologie : Organ der Deutschen Rontgengesellschaft ... [et al] (Strahlenther Onkol) Vol. 196 Issue 7 Pg. 637-646 (Jul 2020) ISSN: 1439-099X [Electronic] Germany
• PMID: 32211942 (Publication Type: Comparative Study, Journal Article)

Chemical References

• Antigens, Neoplasm
• Antigens, Surface
• Gallium Radioisotopes
• Radiopharmaceuticals
• Gallium-68
• FOLH1 protein, human
• Glutamate Carboxypeptidase II

Topics

• Adenocarcinoma (chemistry, radiotherapy, secondary, surgery)
• Aged
• Aged, 80 and over
• Antigens, Neoplasm (analysis)
• Antigens, Surface (analysis)
• Disease-Free Survival
• Follow-Up Studies
• Gallium Radioisotopes
• Glutamate Carboxypeptidase II (analysis)
• Humans
• Kaplan-Meier Estimate
• Lymph Node Excision
• Lymphatic Irradiation
• Lymphatic Metastasis (diagnostic imaging, radiotherapy)
• Male
• Middle Aged
• Neoplasm Staging
• Positron Emission Tomography Computed Tomography
• Prostatectomy (methods)
• Prostatic Neoplasms (pathology, surgery)
• Radiopharmaceuticals
• Retrospective Studies
• Salvage Therapy (methods)