Incidence, Treatment and Outcomes of Patients with Synchronous Lung and Colorectal Malignancies: A Nationwide Inpatient Sample Database (NIS) Analysis

Purpose: Our study aims to describe the incidence, treatment and clinical outcomes of patients with synchronous lung, and colorectal cancer (CRC). Methods: We conducted an 11-years analysis of the Nationwide Inpatient Sample (NIS) database (2002–2012). All adult (age ≥ 18y) patients admitted with a diagnosis of CRC were included. Data abstracted include demographics, malignancy-related variables, treatment, and operative interventions. We excluded patients who had lung metastasis from CRC. Our primary outcome measures were the incidence of synchronous CRC and lung cancer, operative treatment patterns, and mortality. Results: Out of 1,198,421 patients admitted with a CRC diagnosis, 6,231 (0.52%) had synchronous lung cancer. Overall, mean age was 61 ± 15y, 75% were male, and 63% were white. Most patients with synchronous malignancies (56%) had advanced CRC with non-small cell lung cancer (76%). The majority of CRC patients (79%) had recto-sigmoid tumors. Only 11.2% underwent surgical management. No significant difference was noted in the proportion of patients first treated for their CRC relative to those treated for their lung cancer first (p = 0.21). The overall mortality rate was 54%. Conclusion: The incidence of synchronous occurrence of CRC and lung cancer is low, but the mortality is very high. Diagnosis of synchronous cancer is typically incidental. Treatment options for these patients should be tailored to the individual patient. Genetic and epidemiological studies are required to elucidate the potential connection between lung and colon cancer.