Acute pulmonary thromboembolism and occult cancer

Pulmonary thromboembolism (PTE) is an uncommon disease in Asian population when compared with western countries. The definite answer to such a rarity remains unclear. The association of occult malignancy with acute PTE has been well documented in western countries, but has not been reported in Asia. The purpose of this study is to evaluate the occurrence of malignancy after the episode of acute PTE in Chinese patients.

We retrospectively analyzed the patients with acute PTE by chart review (ICD-9:415.9) in Taipei Veterans General Hospital from July, 1993 to June, 1998. Patients were clinically followed in out-patient clinic for at least 12 months.

A total of 45 patients with acute PTE were identified under strict diagnostic criteria. In the follow-up period, 9 patients with cancer were identified. After exclusion of the cases without regular follow-up and those who died on the acute phase of PTE, the adjusted cancer occurrence after or concomitant with acute PTE in our study was 47.37%, which was significantly higher than previous reports. The origins of malignancy were mainly gastrointestinal tract and genitourinary system, similar to the reports from western countries.

The prevalence of occult malignancy after acute PTE is high among Chinese patients in Taiwan. Physicians should be aware of this association, and cancer survey should be performed after the patients are stabilized from acute PTE.