Sleep-disordered breathing, hypoxemia and the association with lung cancer

Sleep-disordered breathing (SDB) and chronic lung diseases have an increasing and even now high prevalence in the general population. Both SDB and chronic lung diseases cause hypoxemic states in affected patients, leading to pathophysiological changes known to be associated with cardiovascular diseases. Chronic lung diseases, such as chronic obstructive pulmonary disease (COPD) and SDB have also been described as being associated with an increased incidence of malignancies per se and especially lung cancer. This article reports on the previously known associations and pathophysiological mechanisms. The SDBs can be manifested in different forms as intermittent and/or chronic hypoxemia. These hypoxemia phenotypes affect vascular growth factors and tumor cell proliferation. Exposure of human lung carcinoma cells (human adenocarcinoma cell line H1437, human squamous cell carcinoma cell line H520) to hypoxemia leads to significantly increased proliferation rates with as yet unknown effects on the response to treatment and the long-term course. Likewise, the clinical effects of SDB and hypoxemia phenotypes on the immediate postoperative course after anatomical lung resections in lung cancer patients have not yet been clarified.