Thromboembolism. Clues for the presence of occult neoplasia

It has been stated that it is inappropriate to conduct an extensive search for occult malignancy in patients with thromboembolism, unless there is some more specific indication. The present study defines those specific indices. By analyzing the clinical features of 11 consecutive patients with occult cancer presenting with thromboembolism (TE), criteria which differentiate TE in occult cancer from TE complicating other disorders were defined. These are the absence of an apparent cause for the TE at the time of the patient's admission, age more than 50 years, multiple sites of venous TE, associated venous and arterial TE, TE resistant to therapy with oral anticoagulants, and the presence of associated paraneoplastic syndromes. The incidence of these parameters in case reports from the literature was also analyzed. The six criteria that were prevalent in our series of patients with paraneoplastic TE, were observed to occur with similar incidence in different groups of historical cases. These criteria may be useful for stratification of patients with TE with regard to the probability of the presence of an occult cancer and the indications for further investigations.