Rate of thromboembolic events in mesothelioma.

BACKGROUND: Thromboembolic event (TEE) rates in the general population and the cancer population are 0.1% to 2% and 10% to 15%, respectively. Our clinical observation is that mesothelioma patients are very susceptible to TEE, including arterial thromboses, but the TEE incidence has not been reported. This retrospective study attempts to determine the rates of TEE in patients with mesothelioma. METHODS: Three hundred seventy-four patients with mesothelioma were identified through the New Mexico SEER database. Sixty-five of them were included in the University of New Mexico tumor registry from 1973 to 2003. Documented TEE rates were abstracted from the patient charts. Chi-square test, Fisher's exact test, and logistic regression were used to identify potentially associated prognostic factors. RESULTS: Fifty-four medical records were reviewed. Patients had a median of six visits (range, 1 to 63 visits). Median age was 60 years (range, 29 to 79 years). Sex distribution was 11 women and 43 men. Anatomic locations of the primary tumor were 35 pleural, 17 peritoneal, 1 pericardial, and 1 pericardial or pleural mesothelioma. The TEE rate was 27.7% (15 of 54), including 10 deep venous thromboses, 2 arterial clots, 2 myocardial infarctions, and 1 pulmonary embolus. No association between the development of TEE and any known prognostic factors were observed. CONCLUSIONS: The 27.7% TEE incidence rate in mesothelioma patients is higher than in other cancer patients. The true incidence of TEE in mesothelioma is likely to be higher than the rate observed in our review, owing to the retrospective nature of the data. Prophylactic anticoagulation trials are recommended to determine the prevention benefit in this high-risk population.

Is human immunodeficiency virus RNA load composed of neutralized immune complexes?

During acute human immunodeficiency virus (HIV) infection, both virus load (HIV RNA) and infectivity are high (10(3)-10(7) RNA copies/mL or TCID(50)/mL) until antibody is produced, which may reduce the HIV infectivity. In HIV carriers, the HIV RNA load is elevated (10(3)-10(5) copies/mL), but infectivity is low (10(0)-10(2) TCID(50)/mL). The low infectivity in carriers could be due to neutralization by antibody in serum, resulting in immune complexes (ICs). We demonstrated that ICs in plasma, prepared with protein A beads, contained HIV RNA (80%-100%) in association with immunoglobulin G (IgG). In comparison, ICs from patients with acute HIV infection and little or no antibody contained virtually no HIV RNA. Moreover, ICs prepared by ultrafiltration contained IgG and specifically and irreversibly neutralized HIV, which indicates that the ICs contained neutralizing antibody. These findings indicate that the HIV RNA in the plasma of carriers is frequently composed of antibody-neutralized HIV as ICs.