Epidemiology of Lung Cancer in Hong Kong

Epidemiology of Lung Cancer in Hong Kong

Introduction

Lung cancer is a health problem that affects global epidemic proportions. Lung cancer (PC) remains to be the leading cause of death around the world. In recent years there have been some changes in recording certain basic epidemiological characteristics, such as age and sex distribution or histologic subtypes. Moreover, other aspects such as clinical presentation, therapeutic, risks of surgery, overall survival and waiting times have not changed much, but there are still significant disparities between the results of the various studies and authors, largely attributable to differences in the methods used. In 2005, 19,115 people died from lung cancer in Hong Kong (Wang et.al, 2009). Despite the increase in the absolute number of deaths since 1950, the adjusted rates in men have declined. The incidence in women, lower than that of other countries, has increased and 1 for every 8.5 men suffers from lung cancer. Over 50% of patients that suffer from lung cancer are older than 70 years. The proportion of adenocarcinoma has increased in the world, although in Hong Kong it is predominantly squamous cell carcinoma (50.5%). Surgical resection (14.8% in Hong Kong, in 2003) has not increased. Operative mortality was 6.8%. 50% of patients receive only palliative medication. Overall absolute survival of lung cancer is less than 10% in many countries. Among resected patients, survival at 5 years (stage IA: 58.3% to 68.5%, stage IIIA: 28.3% to 35.8%) has increased slightly (Fukuoka et.al, 2011).

The death rate from lung cancer slowly and progressively tends to increase in our country. The death rate from this cause was 7.7 per 100,000 in 1970 to 11.68 per 100,000 in 1991 (up 52%).This is mainly linked to the consumption of snuff, as well as risk factors such as exposure to radiation and environmental contaminants, contact with certain chemicals and preexisting lung injury. Mortality from this cause increases throughout life, showing male mortality at all ages. However, this relationship, which in 1970 was 7-1, is currently 4-1, which marks a distinct change in the lifestyles of men and women. The geographic distribution of deaths from this tumor indicates greater epidemiological risk areas in our country, particularly the first and second regions. As explanation for this phenomenon have been proposed environmental and occupational influences. Conservative projections estimate a total of 12,000 annual deaths from this cause in the year 2030 in Hong Kong.

Most commonly recognized risk factors for cancer in the general population include: aging, tobacco use, U.V. radiation, certain chemicals or substances, some viruses and bacteria, a family history of cancer, alcohol consumption, poor diet, lack of physical activity and being overweight. More recent studies have also found numerous links of cancer to inherited genetic predispositions, which emphasizes the importance of family history in cancer prevention. Below is a more detailed review of some of these risk factors that are of particular interest for this project. Recent studies have linked obesity to an increase in both incidence and mortality of certain ...