NEW YORK (Reuters Health) – Evidence from a case-series review and a meta-analysis of other published studies indicates that pelvic lymph node dissection during radical prostatectomy increases the risk of venous thromboembolism (VTE).

The authors of the report in the May issue of the Journal of Urology suggest, “In carefully selected low-risk patients, omitting pelvic lymph node dissection may decrease the incidence of venous thromboembolism.”

Dr. Christian P. Pavlovich and colleagues with the Johns Hopkins Medical Institutions, Baltimore, Maryland reviewed the records of 773 consecutive patients who underwent laparoscopic radical prostatectomy by a single surgeon, with or without pelvic lymph node dissection based on their risk of lymph node metastases. Three patients had incomplete data and were omitted from the analysis.

The investigators found that VTE occurred in 7 of 468 (1.5%) patients who had pelvic lymph node dissection and none of the 302 who did not (p=0.047).

The authors note that the two groups were similar in terms of age, BMI, and prostate size, which have all been proposed as risk factors for thromboembolism. Furthermore, operative times were actually shorter in the lymphadenectomy group, because nerve-sparing surgery was undertaken less often.

Among the patients who underwent pelvic lymph node dissection, the only factor associated with VTE occurrence was BMI; the incidence was 4.4% in those in the top quartile of BMI (p=0.0046)

The researchers found four other relevant studies. Pooling those data indicated that the relative risk for VTE was 2.15 in radical prostatectomy patients who underwent pelvic lymph node dissection compared to those who did not.

Summing up, Dr. Pavlovich and colleagues conclude, “To our knowledge no previous study has demonstrated a statistically significant association between pelvic lymph node dissection during radical prostatectomy and subsequent VTE risk.”

They advise, “We believe that for patients with low-risk prostate cancer undergoing radical prostatectomy, omitting lymphadenectomy decreases the risk of VTE.”

Reference:
Pelvic Lymph Node Dissection is Associated With Symptomatic Venous Thromboembolism Risk During Laparoscopic Radical Prostatectomy
J Urol 2011;185:1661-1668.