Survival may differ by treatment choice among patients with non-metastatic prostate cancer (PCa) who have positive lymph nodes (LN) found at radical prostatectomy, new study findings suggest.
The study showed that both patient- and tumor-related factors influenced treatment selection, Piotr Zareba, MD, MPH, of Memorial Sloan Kettering Cancer Center in New York City, and colleagues reported in the Journal of Urology. Among 7791 patients from the National Cancer Database diagnosed from 2004 to 2010, 63% chose observation, 20% received androgen deprivation therapy (ADT) alone, 5% had radiation therapy (RT) alone, and 13% received a combination of ADT and RT within 12 months of RP.
Results showed that younger men with fewer comorbidities were more likely to receive multimodal therapy. Clinicians were also more likely to use a combination of ADT and RT to manage PCa of a higher grade or stage or with positive surgical margins (PSM).
In agreement with previous studies, patients’ overall survival was 31% and 35% higher with multimodal treatment than with observation or ADT alone, respectively. Survival worsened with grade group 4-5, pT3b-T4, PSM, and more positive lymph nodes (LN), with 3 as the cutoff. As these adverse prognostic factors increased, 10-year overall survival decreased from 84% to 32%.
“Importantly, our findings suggest that clinicians consider the pathologic characteristics of the primary tumor as well as the burden of LN metastases when deciding on management,” Dr Zareba and the team stated. “Specifically, we found that patients with higher grade tumors and a greater number of positive LN were more likely to be managed with ADT alone than either observation, RT alone or combination therapy. This is in spite of the general lack of evidence that men with higher grade disease and higher metastatic LN burden are less likely to benefit from additional local therapy.”
In contrast to these findings, the ECOG (Eastern Cooperative Oncology Group) EST-3886 trial found immediate ADT superior to observation with treatment upon recurrence. More ECOG patients had PSM, seminal vesicle invasion, and multiple positive LN, which may explain the discrepancies, according to the researchers.
Given the limitations of the database, the team could not investigate PSA, adjuvant versus salvage combination therapy, or treatment toxicities.
Zareba P, Eastham J, Scardino PT, and Touijer K. Contemporary patterns of care and outcomes of men found to have lymph node metastases at the time of radical prostatectomy. J Urol. doi: 10.1016/j.juro.2017.06.062.