Bogotá, jul. 25 de 2012 - Agencia de Noticias UN- Close to 90% of lung cancer patients die due to late diagnosis. A pioneering Colombian study will now enable diagnosis in the early stages of the disease.

The numbers are alarming. The World Health Organization (WHO) has revealed that in Latin America alone 56,000 people die per year due to lung cancer. In Colombia, it is the second highest cause of death in men, and the third in women, after violent deaths and cardiovascular disorders.  

The main risk factor associated with the disease is smoking, which holds true in 90% of the cases involving women, and 79% in men. Lung cancer is an abnormal proliferation of lung cells (neoplasia), which is also associated with exposure to substances such as asbestos, radon, arsenic, beryllium, chromium, nickel, air pollution and ionizing radiation.  

Cigarette smoke contains almost sixty of these compounds which are considered carcinogenic by the International Agency for Research on Cancer (IARC). These compounds are absorbed and metabolized by the body, reacting with the DNA, thereby provoking mutations and alterations, which then lead to the development of pre-carcinogenic lesions.  

According to the National Health Institute, (ENS, for its Spanish acronym) in 2007, 35.2% of the Colombian population has smoked at least once in their lifetime; 18.1% of them, between 18 and 69 years of age have smoked one hundred or more cigarettes and 60% of them still smoke. The Colombian provinces with the highest numbers of smokers are Risaralda, Vaupés, Caldas, Antioquia, Tolima, Quindío, Nariño and Chocó, as well as Bogotá, the Capital of Colombia.  

To make matters worse, according to data from the Colombian Anticancer League, each day more youngsters smoke and the age at which they begin to smoke is decreasing. Fifteen years ago, that age was 17, and today it’s just 12.5 years of age.  

Early detection  

Given this alarming set of circumstances, the Pharmacogenetics Group of the Pharmacy Department of the Universidad Nacional de Colombia, headed by Professor Fabio Aristizábal, is working to identify molecular markers which will allow for finding genetic and epigenetic (caused by the individual’s behavior) cell alterations in clinical, non-invasive samples, such as blood plasma.  

With this early detection, patients will not only improve their quality of life, but also, increase their progression-free survival rate. That’s not mentioning the medical cost savings for them, as well as for the national healthcare system.  

According to biologist Sandra Janneth Perdomo, member of the research group, cancer is currently diagnosed primarily by means of thorax X-Rays, CAT scans, bronchoscopies or fine-needle aspiration biopsies, amongst other invasive methods, which can mean certain risks to patients.  

However, these procedures are typically performed in the late stages of the disease, when tumors have already developed, or during cancer metastasis (spreading of cancer to other tissues or organs). These procedures do not detect the molecular changes which are produced in lung tissue at the point of initial outbreak of the disease.  

The high mortality rates are due primarily to late diagnosis of the disease. Therefore, it is necessary to combine different techniques with the use of molecular markers, that is, genes which confirm the presence of abnormal cells present in the respiratory track during the early stages of the disease.  

The research 

For this study, the researchers gathered blood plasma samples and lung tissue (both diseased and normal) from the Santa Clara, Fundación Santa Fe and San Ignacio hospitals, thereby acquiring 55 total samples (36 male and 19 female).  

Perdomo says that they’ve collected samples for a three year period, and have found a group of genes which have enabled them to diagnose early-stage lung cancer. The experts have identified three carcinogenic genes called MYC, AKT2 and MFAP4, which are different in cancer-free patients. Particularly, the gene MFAP4 is associated to lung inflammation, and could potentially be a diagnosis marker.  

This gene becomes altered and therefore mutes other genes which contribute to control tumor growth. This abnormal process is called methylation, therefore the process consists of calculating the methylation rate. For example, in early lung cancer stages, the gene is 1% methylated, while in late stages it is 80% methylated. This suggests that these percentages could serve to assess disease progression.  

This UN advance offers new, promising possibilities for lung cancer patients. Pathology laboratories will now combine traditional testing methods with this new molecular marker diagnosis in order to enable doctors to take more informed therapeutic decisions.  

Although the study was carried out amongst just a few patients, the goal is to perform other analyses which might lead to total certainty regarding the disease, and offer more suitable medical and pharmaceutical treatments. These treatments could then relate specifically to the affected genes, the stage of the disease, and the particular characteristics of each individual. This is pioneering work in  which in the midterm could save many lives. 

Read the complete article in Spanish at UN Periódico n.º 157: http://www.unperiodico.unal.edu.co/dper/article/cancer-de-pulmon-se-diagnosticara-en-fases-iniciales-1.htmlhttp://www.unperiodico.unal.edu.co/dper/article/cancer-de-pulmon-se-diagnosticara-en-fases-iniciales-1.html.

(Por:Fin/clc/fgd)

N° 831