Inclusion Criteria

INCLUSION CRITERIA:

- both sexes;aged>18 years;

- suffering from different types of malignancies(lung, breast,gastric,colon-
rectum,pancreatic,ovarian,head and neck cancer)undergoing systemic chemotherapy,

- having signed Informed Consent prior to initiation of any study procedure.

EXCLUSION CRITERIA:

- adjuvant and neo-adjuvant chemotherapy;

- objectively confirmed venous or arterial thromboembolism in the last three months;

- antithrombotic treatment for other indications;

- life expectancy of less than 3 months;

- Performance Status>2(ECOG);

- active bleeding or bleedings in the last four weeks requiring
hospitalization,transfusion or surgical intervention;

- bleeding diathesis(prothrombin time<70% or activated partial thromboplastin time
ratio>1.3),or platelet count<50x10^9/L;

- cerebrovascular hemorrhage in the last six months;

- known active gastric or duodenal ulcer;

- known cerebral metastasis;

- cerebral aneurysm;

- III-IV grade diabetic retinopathy;

- severe and uncontrolled hypertension(systolic blood pressure>180 mmHg or diastolic
blood pressure>110 mmHg);

- chronic atrial fibrillation;

- acute endocarditis;

- acute pancreatitis;

- known hypersensitivity to unfractionated heparin or LMWH;

- previous occurrence of heparin-induced thrombocytopenia;

- renal impairment (dependent on dialysis or creatinine higher than 2.5mg%);

- liver insufficiency (alanine aminotransferase,aspartate aminotransferase,alkaline
phosphatase levels>3 times the upper limit of the normal ranges and/or total
bilirubin >3.0 mg/ml);

- pregnancy or childbearing potential without adequate contraception;

- treatment with other investigational drugs or patient inclusion in other clinical
trials;

- patients who are unable to fulfill the study requirements in terms of
visits/compliance to treatment.