An increased incidence of ovarian cancer in Japan caused caused by increase in carcinoma

An increased incidence of ovarian cancer in Japan caused caused by increase in carcinoma

(Osaka Medical Center-June 25, 2003)

"The incidence of ovarian cancer among Japanese has increased since the 1970s. Histologic diversity is a characteristic of this cancer. However, there has been no population-based study made on the incidence and survival by histologic type," researchers in Japan report.

"Osaka Cancer Registry's data were used for incidence and survival analyses of ovarian cancer by histologic type in this study. Seven thousand one hundred sixty-seven incident cases were registered during the period 1975 to 1998. According to the IARC's histologic classification, types of ovarian cancer were classified into five categories," wrote A. Ioka and colleagues, Osaka Medical Center, Cancer & Cardiovascular Diseases, Department of Cancer Control & Statistics.

"Survival analysis was restricted to the reported 2431 cases who lived in Osaka Prefecture (except for Osaka City) and were diagnosed in 1975-1994, since active follow-up data on vital status 5 years after the diagnosis were available," the researchers wrote.

"The age-standardized incidence rate of ovarian cancer increased from 4.0 to 5.4 per 100,000 women (standard: world population) in Osaka during the period 1975-1998. Carcinoma, the major histologic category, also increased (from 3.4 to 4.8 per 100 000 women), while sex cordstromal tumors decreased after 1980 and germ cell tumors remained stable," the researchers stated.

"The 5-year relative survival was 36.4% for ovarian cancer patients diagnosed in 1975-1994. The survival for carcinoma was 38.3%, which was lower than that in sex cord-stromal tumors or germ cell tumors (55.3% and 58.6%, respectively). The increase in the incidence of ovarian cancer was caused by the increase in carcinoma," they added.

The researchers concluded: "The relative 5-year survival of ovarian cancer improved over the period, but was different by histologic type."

Ioka and colleagues published their study in Cancer Science (Ovarian cancer incidence and survival by histologic type in Osaka, Japan. Cancer Sci, 2003;94(3):292-296).

For additional information, contact A. Ioka, Osaka Medical Center, Cancer & Cardiovascular Diseases, Department of Cancer Control & Statistics, Higashinari Ku, 1-3-3 Nakamichi, Osaka 5378511, Japan.

The information in this article comes under the major subject areas of Epidemiology, Oncology, Survival & Mortality. This article was prepared by Biotech Week editors from staff and other reports.