Critical Care Medicine-Hematologic and Oncologic Disorders>>>>>Hypercoagulable States
Question 3#

A 58-year-old obese man with pancreatic cancer recently started neoadjuvant chemotherapy before a planned surgical resection. He presents to the emergency department with shortness of breath and chest pain. His hemoglobin is 11.5 g/dL, platelets are 550 × 10 9 /L, and white blood cell count is 10.5 × 10 9 /L. 

He is hemodynamically stable. He had noticed swelling of his left lower extremity a week prior. He denies family history of “clots.” Computed tomography (CT) angiogram revealed pulmonary embolism, and therapeutic anticoagulation is initiated.

Which of the following is a component of the Khorana score that has been validated as a risk factor for the development of venous thromboembolism (VTE) in a patient receiving chemotherapy?

A. Age >55
B. Body mass index (BMI) >30
C. Prechemotherapy platelet count >350 × 109 /L
D. Thyroid cancer

Correct Answer is C

Comment:

Correct Answer: C

Cancer induces a hypercoagulable state that puts patients at risk for thrombotic complications. Up to 10% of patients with cancer may develop VTE. Certain tumor types are associated with higher risk: for example, 30% to 50% of patients with pancreatic cancer have evidence of thrombosis.

The Khorana risk score for VTE in cancer patients is a validated scoring tool intended to be used in patients undergoing chemotherapy to stratify patients in terms of their future risk of VTE. The tool can be used to identify patients who are high risk and select those patients for ultrasound screening to diagnose DVT early. Data regarding use of the score for selecting patients for thromboprophylaxis are pending.

Components of the score are:

  1. Cancer type (stomach, and pancreas get two points, lung, lymphoma, gynecologic, bladder, and testicular cancers get one point)
  2. Prechemotherapy platelet count of ≥350 × 109/L, hemoglobin level <10 g/dL
  3. prechemotherapy leukocyte count >11 × 109/L
  4. BMI ≥35 kg/m2

A score of ≥3 infers a 6.7% to 7.1% risk of VTE in 2.5 months. 

References:

  1. Chew HK, Wun T, Harvey D, et al. Incidence of venous thromboembolism and its effect on survival among patients with common cancers. Arch Intern Med. 2006;166:458.
  2. Lyman GH, Khorana AA, Kuderer NM, et al. Venous thromboembolism prophylaxis and treatment in patients with cancer: American Society of Clinical Oncology clinical practice guideline update. J Clin Oncol. 2013;31(17):2189-2204. doi:10.1200/JCO.2013.49.1118. Epub 2013 May 13.
  3. Khorana AA, Kuderer NM, Culakova E, et al. Development and validation of a predictive model for chemotherapy-associated thrombosis. Blood. 2008;111:4902-4907.
  4. Dutia M, White RH, Wun T. Risk assessment models for cancerassociated venous thromboembolism. Cancer. 2012;118:3468-3476.