Sputum analysis: non-invasive early lung cancer detection.

Lung cancer is the leading cause of cancer-related deaths over the world, characterized by a very high mortality rate. Molecular technique development tries to focus on early detection of cancers by studying molecular alterations that characterize cancer cells. Worldwide lung cancer research has focused on an ever-increasing number of molecular elements of carcinogenesis at genetic, epigenetic and protein levels. The non-invasiveness is the characteristic that all clinical trials on cancer detection should have. Abnormal chest imaging and/or non-specific symptoms are initial signals of lung cancer that appear in an advanced stage of disease. This fact represents the cause of the low 5-year survival rate: over 90% of patients dying within 5 years of diagnosis. Since smokers have higher quantity of sputum containing exfoliated cells from the bronchial tree, and the sputum represents the most easily accessible biological fluid and its collection is non-invasive, analysis of this sample represents a good area of research in early lung cancer diagnosis. Continued cigarette smoking is the cause of chronic obstructive pulmonary disease (COPD), with an estimated attributable risk factor exceeding 80% in smoking affected individuals. Lung cancer is found in 40-70% of patients with COPD, particularly in severe disease, and it is a common cause of death in these patients. A large prospective trial of almost half a million non-smokers showed as lung cancer is also common in patients with COPD who have never smoked. This review describes issues related to early lung cancer screening using non-invasive methods.

Cytometry and DNA ploidy: clinical uses and molecular perspective in gastric and lung cancer.

Flow cytometry is one of the most powerful and specific methods used for the integrated study of the molecular and morphological events occurring during cell proliferation. Many methods have been described for investigating this process. Several cell cycle regulators controlling the correct entry and progression through the cell cycle are altered in tumors. In fact, in most, if not all, human cancers there is a deregulated control of G1 phase progression, the period when cells decide if they will start proliferation or stay quiescent. Cytometry (flow and image) is able to analyze DNA content thanks to the use of the same "molecule" conjugates with a fluorochrome that permits to identify DNA content of single cell in a sample. Most important results of studies on DNA ploidy have been reviewed during the last years and as a result the analyses of DNA ploidy in cancer may provide clinically useful information on diagnostic, therapeutic and prognostic aspects. In fact, aneuploid cancer has a high proliferative activity and a metastatic or invasive potential, markers of a poor prognosis. Multiparametric flow cytometry should allow the simultaneous determination of morphology, phenotype, intracellular protein expression, and status of chromatin and DNA. Evaluating if a particular protein is responsible for the aggressiveness of cancer, or the alteration of DNA content, or if the activation of its state is the cause of rapid growth of cancer cells, is very important and it can facilitate the clinical treatment of patients.