RESEARCH HIGHLIGHTS Nature Reviews Urology 11, 539 (2014); published online 9 September 2014; doi:10.1038/nrurol.2014.247
SURGERY
Venous thromboembolism and urological surgery
Mark Strozier/iStock/Thinkstock
P
ublication of results from three studies has cast fresh light on the risks of venous thromboembolism (VTE) following surgery for urological malignancies. These risks vary according to the nature of the cancer and the surgery; predictive factors for VTE similarly vary. Although the results of one trial demonstrated a strong association of pelvic lymph-node dissection (PLND) with the incidence of VTE, this was not replicated in the largest of the three studies. The relatively high risks of VTE in the period following discharge from hospital emphasize the need to optimize postoperative thromboprophylaxis. In Urology, Alberts et al. presented results gleaned from the US National Surgical Quality Improvement Program database on 27,455 patients undergoing major surgery for urological malignancies. The incidences of VTE within 30 days of surgery were 5.5% for radical cystectomy (113 cases in 2,065 patients), 1.9% for nephroureterectomy (17 in 890), 1.1% for radical nephrectomy (52 in 4,568), 1.1% for radical prostatectomy (178 in 16,848) and 1.0% for partial nephrectomy (31 in 3,084). The risk factors that were significantly associated with pelvic procedures were BMI ≥30 kg/m2, metastatic disease and operation time >6 h. The factors associated with upper tract surgeries were a history of severe, chronic obstructive pulmonary disease, preoperative serum albumin 6 h. Risks of VTE were lower for current smokers compared with nonsmokers (OR 0.45), and for minimally invasive surgery compared with open surgery (OR 0.53). Overall 30-day postoperative mortality in this group of patients was 0.5% (137 deaths in 27,455 patients), but mortality for patients with VTE was 5.4% (21 in 391). 63.4% of VTEs occurred after hospital discharge, although the figure for radical prostatectomies was 82.6%. The second study, conducted by Sun et al. also aimed to determine the rate,
timing and predictors of VTE, exclusively in the setting of open radical cystectomy with extended PLND for urothelial bladder cancer. The incidence of symptomatic VTE within 3 months of surgery was 4.7% (109 in 2,316 patients), with 57.8% of these occurring after discharge, at a median of 20 days postoperatively. Increased BMI, positive surgical margins, orthotopictype diversion and increased length of hospitalization were all significantly associated with increased risk of VTE. The authors speculated that identified risk factors were surrogates for the presence of malignancy after surgery, length of operation, poor baseline health and surgical complications. Notably, no significant difference was noted between VTE rates prior to 2008, when warfarin was used for VTE prophylaxis, and after 2008, when unfractionated heparin prophylaxis was used along with sequential compression devices (in accordance with American Urological Association guidelines). This result opposes previous evidence of the superiority of heparin over warfarin in this setting.
NATURE REVIEWS | UROLOGY
In the third study, Tyritzis et al. assessed the influence of PLND on the incidence of VTE after radical prostatectomy. Among 3,544 patients enrolled in the Swedish multicentre LAPPRO trial, PLND was associated with a sevenfold increase in the risk of VTE. Open surgery was also predictive of VTE, compared with robot-assisted laparoscopic radical prostatectomy. These results contrast with those of Alberts et al., who did not find significant effects of the type of prostatectomy, or the use of PLND, on the incidence of VTE. Whether or not the benefits of PLND outweigh the risks is still open to question. Despite the potential relevance of extended prophylaxis to the incidence of postdischarge VTE, its use was inconsistently reported in these studies. At the University of Southern California, Sun et al. reported that none of the patients included in their study were given postdischarge anticoagulation. However, their results have now prompted a change in practice at their institution. Following radical cystectomy, patients are now sent home with a 1-month supply of low molecular weight heparin. However, this ad hoc practice modification does not help the broader population of patients undergoing urological surgery. Clear and consistent guidelines are required for VTE prophylaxis in the period following hospital discharge after urological surgery. To establish these guidelines, the efficacy and practicability of extended VTE prophylaxis must be established. Robert Phillips Original articles Alberts, B. D. et al. Venous thromboembolism after major urologic oncology surgery: a focus on the incidence and timing of thromboembolic events after 27,455 operations. Urology doi:10.1016/j.urology.2014.05.055 | Sun, A. J. et al. Venous thromboembolism following radical cystectomy: significant predictors, comparison of different anticoagulants, and timing of events. J. Urol. doi:10.1016/ j.juro.2014.08.085 | Tyritzis, S. I. et al. Thromboembolic complications in 3544 patients undergoing radical prostatectomy with or without lymph node dissection. J. Urol. doi:10.1016/j.juro.2014.08.091
VOLUME 11 | OCTOBER 2014 © 2014 Macmillan Publishers Limited. All rights reserved
SURGERY
Venous thromboembolism and urological surgery
Mark Strozier/iStock/Thinkstock
P
ublication of results from three studies has cast fresh light on the risks of venous thromboembolism (VTE) following surgery for urological malignancies. These risks vary according to the nature of the cancer and the surgery; predictive factors for VTE similarly vary. Although the results of one trial demonstrated a strong association of pelvic lymph-node dissection (PLND) with the incidence of VTE, this was not replicated in the largest of the three studies. The relatively high risks of VTE in the period following discharge from hospital emphasize the need to optimize postoperative thromboprophylaxis. In Urology, Alberts et al. presented results gleaned from the US National Surgical Quality Improvement Program database on 27,455 patients undergoing major surgery for urological malignancies. The incidences of VTE within 30 days of surgery were 5.5% for radical cystectomy (113 cases in 2,065 patients), 1.9% for nephroureterectomy (17 in 890), 1.1% for radical nephrectomy (52 in 4,568), 1.1% for radical prostatectomy (178 in 16,848) and 1.0% for partial nephrectomy (31 in 3,084). The risk factors that were significantly associated with pelvic procedures were BMI ≥30 kg/m2, metastatic disease and operation time >6 h. The factors associated with upper tract surgeries were a history of severe, chronic obstructive pulmonary disease, preoperative serum albumin 6 h. Risks of VTE were lower for current smokers compared with nonsmokers (OR 0.45), and for minimally invasive surgery compared with open surgery (OR 0.53). Overall 30-day postoperative mortality in this group of patients was 0.5% (137 deaths in 27,455 patients), but mortality for patients with VTE was 5.4% (21 in 391). 63.4% of VTEs occurred after hospital discharge, although the figure for radical prostatectomies was 82.6%. The second study, conducted by Sun et al. also aimed to determine the rate,
timing and predictors of VTE, exclusively in the setting of open radical cystectomy with extended PLND for urothelial bladder cancer. The incidence of symptomatic VTE within 3 months of surgery was 4.7% (109 in 2,316 patients), with 57.8% of these occurring after discharge, at a median of 20 days postoperatively. Increased BMI, positive surgical margins, orthotopictype diversion and increased length of hospitalization were all significantly associated with increased risk of VTE. The authors speculated that identified risk factors were surrogates for the presence of malignancy after surgery, length of operation, poor baseline health and surgical complications. Notably, no significant difference was noted between VTE rates prior to 2008, when warfarin was used for VTE prophylaxis, and after 2008, when unfractionated heparin prophylaxis was used along with sequential compression devices (in accordance with American Urological Association guidelines). This result opposes previous evidence of the superiority of heparin over warfarin in this setting.
NATURE REVIEWS | UROLOGY
In the third study, Tyritzis et al. assessed the influence of PLND on the incidence of VTE after radical prostatectomy. Among 3,544 patients enrolled in the Swedish multicentre LAPPRO trial, PLND was associated with a sevenfold increase in the risk of VTE. Open surgery was also predictive of VTE, compared with robot-assisted laparoscopic radical prostatectomy. These results contrast with those of Alberts et al., who did not find significant effects of the type of prostatectomy, or the use of PLND, on the incidence of VTE. Whether or not the benefits of PLND outweigh the risks is still open to question. Despite the potential relevance of extended prophylaxis to the incidence of postdischarge VTE, its use was inconsistently reported in these studies. At the University of Southern California, Sun et al. reported that none of the patients included in their study were given postdischarge anticoagulation. However, their results have now prompted a change in practice at their institution. Following radical cystectomy, patients are now sent home with a 1-month supply of low molecular weight heparin. However, this ad hoc practice modification does not help the broader population of patients undergoing urological surgery. Clear and consistent guidelines are required for VTE prophylaxis in the period following hospital discharge after urological surgery. To establish these guidelines, the efficacy and practicability of extended VTE prophylaxis must be established. Robert Phillips Original articles Alberts, B. D. et al. Venous thromboembolism after major urologic oncology surgery: a focus on the incidence and timing of thromboembolic events after 27,455 operations. Urology doi:10.1016/j.urology.2014.05.055 | Sun, A. J. et al. Venous thromboembolism following radical cystectomy: significant predictors, comparison of different anticoagulants, and timing of events. J. Urol. doi:10.1016/ j.juro.2014.08.085 | Tyritzis, S. I. et al. Thromboembolic complications in 3544 patients undergoing radical prostatectomy with or without lymph node dissection. J. Urol. doi:10.1016/j.juro.2014.08.091
VOLUME 11 | OCTOBER 2014 © 2014 Macmillan Publishers Limited. All rights reserved
