Salvage pelvic lymph node dissection for lymph node recurrent prostate cancer

Salvage lymphadenectomy after primary therapy with curative intent for prostate cancer

PURPOSE OF REVIEW

To provide a summary of the current literature on salvage lymph node dissection (sLND) in patients with nodal recurrent prostate cancer (PCa) with focus on imaging, the extent of sLND and oncologic outcomes.

RECENT FINDINGS

The clinical practice guidelines recommend performing PET/CT in patients with biochemical recurrence (BCR) after primary therapy. PSMA PET/CT has demonstrated superiority over choline PET/CT and MRI, especially at low prostate-specific antigen (PSA) levels. Although the heterogeneity in available literature does not allow standardization of surgical templates for sLND and PET/CT scan can guide the extent of surgical dissection, an anatomically defined extended template is typically considered. Radio-guided surgery (RGS) suggests an improved positive lymph node yield compared with standard sLND. However, long-term data are needed to evaluate the oncologic impact of sLND. The main aims of sLND are to delay recurrence and to postpone the need for systemic therapy. Available evidence suggests that around 40-80% of men can achieve complete biochemical response after sLND and 10-30% remain BCR free after 5 years. Robotic sLND might represent an option to reduce the risk of complications without compromising oncological outcomes; validation in controlled prospective studies is, however, needed.

SUMMARY

sLND is a valid treatment option for patients with nodal recurrence only after primary therapy for PCa. Further optimization of patient selection based on highly sensitive and specific imaging and clinical factors remains an unmet need. To maximize the benefit of this approach, sLND should be discussed with patients who harbor lymph node-only recurrence after primary therapy in a shared decision-making.

Elective nodal radiotherapy in prostate cancer

In patients with prostate cancer who have a high risk of pelvic nodal disease, the use of elective whole pelvis radiotherapy is still controversial. Two large, randomised, controlled trials (RTOG 9413 and GETUG-01) did not show a benefit of elective whole pelvis radiotherapy over prostate-only radiotherapy. In 2020, the POP-RT trial established the role of elective whole pelvis radiotherapy in patients who have more than a 35% risk of lymph node invasion (known as the Roach formula). POP-RT stressed the importance of patient selection. In patients with cN1 (clinically node positive) disease or pN1 (pathologically node positive) disease, the addition of whole pelvis radiotherapy to androgen deprivation therapy significantly improved survival compared with androgen deprivation therapy alone, as shown in large, retrospective studies. This patient population might increase in the future because use of the more sensitive prostate-specific membrane antigen PET-CT will become the standard staging procedure. Additionally, the SPORTT trial suggested a benefit of whole pelvis radiotherapy in biochemical recurrence-free survival in the salvage setting. A correct definition of the upper field border, which should include the bifurcation of the abdominal aorta, is key in the use of pelvic radiotherapy. As a result of using modern radiotherapy technology, severe late urinary and intestinal toxic effects are rare and do not seem to increase compared with prostate-only radiotherapy.

Can 68Ga-prostate specific membrane antigen positron emission tomography/computerized tomography provide an accurate lymph node staging for patients with medium/high risk prostate cancer? A diagnostic meta-analysis

Objective

This article aims to evaluate the diagnostic value of ⁶⁸Gallium-PSMA positron emission tomography/computerized tomography (⁶⁸Ga-PSMA PET/CT) for lymph node (LN) staging in patients with prostate cancer (PCa) by a meta-analysis of diagnostic tests.

Methods

We systematically retrieved articles from Web of Science, EMBASE, Cochrane Database, PubMed. The time limit is from the creation of the database until June 2019, and Stata 15 was used for calculation and statistical analyses.

Results

Sensitivity, specificity, positive and negative likelihood ratio (PLR, NLR), diagnostic odds ratio (DOR) and 95% confidence intervals (CI) be used to evaluate the diagnostic value. A total of 10 studies were included in our meta-analysis, which included 701 individuals. The results of each consolidated summary are as follows: sensitivity of 0.84 (95% CI 0.55–0.95), specificity of 0.95 (95% CI 0.87–0.98), PLR and NLR was 17.19 (95% CI 6.27, 47.17) and 0.17 (95% CI 0.05–0.56), respectively. DOR of 100 (95% CI 18–545), AUC of 0.97 (95% CI 0.95–0.98).

Conclusion

Our study demonstrates that ⁶⁸Ga-PSMA PET/CT has a high overall diagnostic value for LN staging in patients with moderate and high-risk PCa. But our conclusions still require a larger sample size, multi-center prospective randomized controlled trial to verify.