Venous Thromboembolism Risk Increases, Persists After Cancer Surgery

Investigators have provided precise estimates of excess venous thromboembolism (VTE) risk after major cancer surgery by cancer type.

Using multiple Swedish nationwide registers such as the national cancer register, investigators assessed VTE risk in 432,218 patients who underwent major surgery for cancer of the urinary bladder, breast, colon or rectum, gynecologic organs, kidney or upper urinary tract urothelial cancer, lung, prostate, or stomach or esophagus from 1987 to 2016. Each patient with cancer was matched to 10 cancer-free adults.

The 1-year absolute risk of pulmonary embolism and deep vein thrombosis (DVT) was lowest after prostate cancer surgery and highest after bladder cancer surgery, Johan Björklund, MD, PhD, of Karolinska Institutet, in Stockholm, Sweden, and colleagues reported in JAMA Network Open.

For pulmonary embolism, the 1-year absolute excess risks were 2.69% for bladder cancer, 0.59% for breast cancer, 1.57% for colorectal cancer, 1.32% for gynecologic organ cancer, 1.38% for kidney and upper urinary tract cancer, 2.61% for lung cancer, 2.13% for gastroesophageal cancer, and 0.57% for prostate cancer.

For DVT, the 1-year absolute excess risks were 4.67% for bladder cancer, 1.36% for breast cancer, 2.15% for colorectal cancer, 2.02% for gynecologic organ cancer, 2.14% for kidney and upper urinary tract cancer (UTUC), 1.40% for lung cancer, and 2.19% for gastroesophageal cancer.

VTE risk was highest right after surgery, then declined and held steady at approximately 90 to 120 days, the investigators reported. The highest VTE risk was observed after lung cancer surgery: a significant 25.7-, 18.6-, and 8.9-fold increased risk at 30, 90, and 365 days, respectively, for patients compared with cancer-free adults. After bladder cancer surgery, VTE risk was a significant 16.3-, 9.6-, and 5.2-fold higher for patients at 30, 90, and 365 days, respectively. For kidney cancer and UTUC, VTE risk was significantly elevated 12.2-, 4.2, and 3.3-fold at the respective time periods. For prostate cancer, VTE risk was significantly increased 13.9- and 1.7-fold only at 30 and 90 days, respectively.

Both surgery and systemic treatments, such as chemotherapy, may contribute to thromboembolism, Dr Björklund’s team pointed out. The study lacked information on nonsurgical treatments, precluding further analyses. They noted that pelvic lymph node dissections have been associated with VTE, which may explain why prostate, bladder, and gynecologic cancer surgery have higher peak rates than colorectal cancer surgery. What’s clear is that VTE risk persists beyond in-hospital or 28-day extended thromboprophylaxis.

“The results highlight the need for individualized venous thromboembolism risk evaluation and prophylaxis regimens for patients undergoing surgery for different cancers,” Dr Björklund’s team concluded. Key decisions include timing, duration, dosage, and choice of prophylaxis.

This article originally appeared on Renal and Urology News