RATIONALE: Chemotherapy may cause blood clots to form in the thigh, leg, and lung. This study may help doctors understand how often blood clots occur in patients undergoing chemotherapy.

PURPOSE: This clinical trial is studying how often blood clots occur in patients undergoing chemotherapy for solid tumors, including colorectal cancer, stomach cancer, lung cancer, ovarian cancer, pancreatic cancer, prostate cancer, or metastatic breast cancer

OBJECTIVES:

• Determine the incidence of venous thromboembolic events (i.e., deep vein thrombosis and/or pulmonary embolism) in patients undergoing chemotherapy for solid tumors.

OUTLINE: This is a prospective, multicenter survey.

Patients undergo observation beginning on day 1 of chemotherapy and continuing for up to 3 months in the absence of symptomatic, confirmed deep vein thrombosis or pulmonary embolism; use of anticoagulant therapy for more than 5 days as curative treatment; or initiation of thromboprophylaxis for any reason. Patients undergo bilateral compression ultrasound of the lower limbs at baseline and at 3 months (or at an earlier timepoint, if indicated).

PROJECTED ACCRUAL: A total of 2,000 patients will be accrued for this study.

DISEASE CHARACTERISTICS:

• Cytologically or histologically confirmed diagnosis of 1 of the following:

  • Metastatic breast cancer
  • Colorectal cancer
  • Gastric cancer
  • Lung cancer
  • Ovarian cancer
  • Pancreatic cancer
  • Hormone-refractory prostate cancer

• Scheduled to undergo chemotherapy for ≥ 3 months

  • Chemotherapy for colorectal, gastric, lung, ovarian, or pancreatic cancer may be administered in the neoadjuvant, adjuvant, or palliative setting

• History of deep vein thrombosis or pulmonary embolism allowed if treatment and secondary prevention of the last episode was completed prior to study entry

  • Negative baseline bilateral compression ultrasonography

PATIENT CHARACTERISTICS:

• Life expectancy > 3 months

PRIOR CONCURRENT THERAPY:

• See Disease Characteristics

• More than 6 weeks since prior chemotherapy*

  • Hormonal therapy alone is not considered chemotherapy

• More than 4 weeks since prior major surgery, including surgery for cancer

  • Minor surgery (e.g., implant of a port-a-cath) within the past 4 weeks allowed

• No concurrent major surgery, including surgery for cancer, during the observation period

• Radiotherapy before or during the observation period allowed

• Concurrent chemotherapy* in combination with additional hormonal therapy allowed

• Concurrent treatment (with the exception of antithrombotic therapy) in any other clinical trial allowed

• No concurrent or scheduled use of thromboprophylaxis or any anticoagulant therapy, including any of the following:

  • Parenteral anticoagulants (e.g., heparin, low molecular-weight heparin, or other agents, such as fondaparinux or bivalirudin)

  • Oral anticoagulants (e.g., vitamin K antagonists)

  • Thrombolytic agents

    • Chronic treatment with antiplatelet agents, such as low-dose aspirin (≤ 300 mg/day) or clopidogrel allowed NOTE: *Chemotherapy is defined as treatment with any antineoplastic agent, including biologicals