Chronic obstructive pulmonary disease as a risk factor for lung cancer

How to target small cell lung cancer

Small cell lung cancer (SCLC) is a highly malignant disease with dismal prognosis. Although great progress has been made in investigating genetic aberrations and putative drivers of this tumor entity, the mechanisms of rapid dissemination and acquisition of drug resistance are not clear. The majority of SCLC cases are characterized by inactivation of the tumor suppressors p53 and retinoblastoma (Rb) and, therefore, interchangeable drivers will be difficult to target successfully. Access to pure cultures of SCLC circulating tumor cells (CTCs) and study of their tumor biology has revealed a number of new potential targets. Most important, expression of chitinase-3-like-1/YKL-40 (CHI3L1) which controls expression of vascular epithelial growth factor (VEGF) and matrix metalloproteinase-9 (MMP9) was newly described in these cells. The process switching CHI3L1-negative SCLC cells to CHI3L1-positive CTCs seems to be associated with cytokines released by inflammatory immune cells. Furthermore, these CTCs were found to promote monocyte-macrophage differentiation, most likely of the M2 tumor-promoting type, recently described to express PD-1 immune checkpoint antigen in SCLC. In conclusion, dissemination of SCLC seems to be linked to conversion of regular tumor cells to highly invasive CHI3L1-positive CTCs, which are protected by immune system suppression. Besides the classical targets VEGF, MMP-9 and PD-1, CHI3L1 constitutes a new possibly drugable molecule to retard down dissemination of SCLC cells, which may be similarly relevant for glioblastoma and other tumor entities.

Smoking, inflammation and small cell lung cancer: recent developments

Small cell lung cancer (SCLC) accounts for 15 % of all lung tumors and represents an invasive neuroendocrine malignancy with poor survival rates. This cancer is highly prevalent in smokers and characterized by inactivation of p53 and retinoblastoma. First in vitro expansion of circulating tumor cells (CTCs) of SCLC patients allowed for investigation of the cell biology of tumor dissemination. In the suggested CTC SCLC model, the primary tumor attracts and educates tumor-promoting and immunosuppressive macrophages which in turn arm CTCs to spread and generate distal lesions. Preexisting inflammatory processes associated with chronic obstructive pulmonary disease (COPD) seem to potentiate the subsequent activity of tumor-associated macrophages (TAM). Activation of signal transducer and activator of transcription 3 (STAT3) and expression of chitinase-3-like 1/YKL-40 in SCLC CTCs seems to be associated with drug resistance. In conclusion, inflammation-associated generation of invasive and chemoresistant CTCs most likely explains the characteristic features of SCLC, namely early dissemination and rapid failure of chemotherapy.

Video-assisted thoracoscopic surgery for non-small-cell lung cancer is beneficial to elderly patients

The aim of this study was to explore whether video-assisted thoracoscopic surgery (VATS) has short or long-term benefits in elderly patients with non-small-cell lung cancer compared with open surgery. Between June 2007 and December 2014, 579 patients older than 70 years underwent radical pulmonary resection for non-small-cell lung cancer, including 138 who received VATS and 441 who received open surgery. A retrospective pair-matched study was performed to compare 194 patients (97 pairs) who underwent either VATS or open resection. Patients were matched by age, sex, comorbidity, American Society of Anesthesiologists (ASA) score, tumor location, clinical TNM stage, and extent of pulmonary resection. Short and long-term outcomes were compared between the two groups. The overall incidence of postoperative 30-day complications was significantly lower in the VATS group than in the open surgery group. The major postoperative 30-day complication trended lower in the VATS group but was not significantly different. The length of postoperative hospital stay was significantly shorter. Kaplan-Meier analysis showed that 5-year disease-free survival and overall survival was similar between the two groups. In summary, in surgical management of elderly patients with non-small-cell lung cancer, VATS is associated with lower rates of morbidity as well as comparable disease-free survival and overall survival outcomes.

The association between combined non-cystic fibrosis bronchiectasis and lung cancer in patients with chronic obstructive lung disease

BACKGROUND

Whereas the epidemiological association between lung cancer and chronic obstructive pulmonary disease (COPD), a chronic inflammatory respiratory disease, is well known, limited studies have examined the association between lung cancer and non-cystic fibrosis bronchiectasis, a representative chronic airway inflammatory disease. This study evaluated the association between bronchiectasis and lung cancer in patients with COPD.

METHODS

A matched case-control study was conducted in a referral hospital in South Korea. Among COPD patients with moderate to very severe airflow limitation (forced expiratory volume in one second/forced vital capacity <0.7 and forced expiratory volume in one second ≤70% [% predicted]) who underwent chest computed tomography (CT) between January 1, 2010 and May 30, 2013, patients with lung cancer and controls matched for age, sex, and smoking history were selected. The risk of lung cancer was assessed according to the presence of underlying bronchiectasis confirmed by chest CT.

RESULTS

The study enrolled 99 cases and 198 controls. Combined bronchiectasis on chest CT was inversely associated with the risk of lung cancer compared with controls (odds ratio [OR] 0.25, 95% confidence interval [CI] 0.12-0.52, P<0.001). Significant associations were found in patients with squamous cell carcinoma (OR 0.11, 95% CI 0.03-0.49, P=0.001) and history of smoking (OR 0.27, 95% CI 0.12-0.57, P<0.001). However, the severity and location of bronchiectasis were not associated with the risk of lung cancer.

CONCLUSION

Interestingly, the concomitant presence of bronchiectasis in COPD patients was associated with a lower risk of lung cancer.