[Clinical characteristics of lung cancer complicated with pulmonary embolism]

To investigate the clinical characteristics, risk factors, and survival time of patients with lung cancer (LC) and pulmonary embolism (PE).

A total of 17 LC patients complicated with PE admitted to this hospital from February 2012 to January 2014 were retrospectively reviewed. There were 13 males and 4 females, with an average age of (65±9) years (range, 38-82 years). Twenty LC patients, including 14 males and 6 females with an average age of (63±9) years (range, 34-81 years), and 10 PE patients , including 7 males and 3 females with an average age of (70±7) years (range, 42-85 years), were selected respectively as the LC control group and the PE control group. Logistic regression analysis was used to evaluate the risk factors for LC complicated with PE. The survival of these patients was compared with that of the control subjects by Kaplan-Meier analysis.

In the 17 patients with LC and PE, the diagnosis of PE was made simultaneously with LC in 2, before the diagnosis of LC in 4, and after the diagnosis of LC in 11 patients. These patients showed a higher incidence of unexplained dyspnea (12 cases) than those with LC only (6 cases) (P<0.05). These patients also had a higher incidence of cough (11 cases) than those with PE only (2 cases) (P<0.05). The patients with both PE and LC had a lower PaO2 (67±18) mmHg (1 mmHg=0.133 kPa) than those with LC only (87±12) mmHg (P<0.05). They also showed higher WBC count (8.9±5.3) g/L and D-Dimer level (850±537) μg/L than those with LC only (4.5±3.0) g/L, (306±188) μg/L (P<0.05). Multi-factor analysis showed that Hb<100 g/L, WBC>11×10(9)/L, D-Dimer>500 μg/L, PO2<80 mmHg, adenocarcinoma, and high pathological grade (TNM grade) were the risk factors for LC with PE (odds ratio 1.58, 2.24, 3.06, 3.15, 3.44, 2.09, respectively). On January 31, 2014, the median survival time of patients with LC and PE was 8.7 months, which was significantly lower than that of patients with LC only (P<0.05).

The common clinical manifestations in patients with both LC and PE included unexplained dyspnea, fever and cough. The most common pathological type was adenocarcinoma. The first 5 months after LC diagnosis were the peak time for PE. Patients with LC and PE had a shorter survival time. LC of grade III to IV, lower Hb, higher WBC, higher D-Dimer and hyoxemia were independent risk factors for LC complicated with PE.