Colorectal cancer worldwide, cases

The colon is a muscular organ and the last part of the digestive system in human, and the rectum is the final portion of the colon. Colorectal cancer is the third most common type worldwide (Boyle and Ferlay, 2005 Parkin, 2004) after limg and stomach cancer. Among them colon cancer is more frequent than rectal cancer. Especially in developed countries, the ratio of colon to rectum cancer cases can increase up to 2 1 or more. However, in nonindustrialized countries, rates are almost similar. On the other hand, comparison of the incidence rate of colon cancer in developed and underdeveloped countries shows that colorectal cancer is more common in industrialized countries. Also 50% of the colorectal cancer death has been seen in developed countries (Tyczynski et al., 2003). It remains relatively uncommon in Africa and much of Asia. And rates of this cancer increase with industrialization and urbanization. It has been much more common in high income countries, but also now increasing in middle- and low-income countries too. It remains relatively higher in North America, Europe, and Australia rather than South America, Asia, and Africa (Parkin, 2004). 

Carcinoma of the uterine cervix is the third most common malignancy in women worldwide after breast and colorectal cancers (Parkin et al. 1999). Approximately 371,200 new cases of cervical cancer occur each year throughout the world, accounting for 10% of all cancers in women. The American Cancer Society estimated that 12,900 cases of invasive cervical cancer were expected to be diagnosed in 2001 in the United States. Primarily because of screening with the Pap smear, the incidence and mortality rates for cervical cancer have declined in most developed countries. Between 1993 and 1997, the incidence rate in black women (11.4 per 100,000) was higher than the rate in white women (7.1 per 100,000). An estimated 4,400 cervical cancer deaths were expected to occur in 2001 in the U.S. Since 1982, cervical cancer mortality rates have declined at an average of about 1.5% per year. 

Cancer is a major health issue worldwide. The most common solid tumors are breast, colorectal, ovarian, prostate and lung cancer, which account for more than 3.2 million new cases annually, and 1.7 million deaths each year [1]. In addition, large numbers of individuals are diagnosed with and die each year from hematological malignancies such as lymphomas (>166000 new cases and 93 000 deaths, respectively) or leukemias (144000 new cases and 109000 deaths, respectively). Early detection combined with advances in surgery and external radiotherapy have improved the prognosis for many patients with solid tumors in which the disease is confined to the primary anatomical site, but the outlook for patients with advanced disseminated cancer remains poor. Lymphomas and leukemias are more... 

Primary and secondary malignant hepatic tumors are a major health problem worldwide. While metas-tases are common in western countries, primary liver cancers are frequently diagnosed in Asia and Africa. However, recent data suggest that the incidence and mortality of hepatocellular carcinoma (HCC) in Western nations are on the rise (Taylor-Robinson et al. 1997 Llovet et al. 2003). Likewise, the liver is the most common site for metastases. In 25%-50% of patients with malignancies liver metastases were observed at autopsy (Bernardino et al. 1982). The most frequent primary sites are colon, breast, pancreas, and lung. In the case of colorectal metastatic disease, the liver is the only metastatic site in 20%-30% of patients (Sasson and Sigurdson 2002). 

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