Morphological distribution of ovarian cancer from Cancer Incidence in Five Continents Vol. X: Figure 1.

Abstract

In order to compare the morphological distribution of cancer incidence worldwide, we abstracted the incidence in 2003–2007 from Cancer Incidence in Five Continents Vol. X (CI5-X). The International Agency for Research on Cancer provides the CI5 detailed databases on the incidence of cancer recorded by cancer registries (regional and national) worldwide. We used the number of incidences in Japan, the Republic of Korea, the USA, Brazil, the UK, Italy and Australia from the CI5 database which contains the incidence for selected cancer registries published in CI5-X for 2003–2007. The Republic of Korea and the USA (NPCR: National Program of Cancer Registries) reported the cancer incidence covered by all the country; however, the remaining countries reported the cancer incidence by registry. We aggregated eight registries in Japan, two registries in Brazil, four registries in the UK, 21 registries in Italy, and five registries in Australia. We compared the morphological distribution between countries for ovarian cancer coded as C56 (ICD10). Ovarian cancer was one of the 10 most common cancers among females in all countries studied, accounting for 2.4–3.8% of all cancer incidences. Figure 1 shows the distribution of morphology for ovarian cancer. In the UK, in which the age-standardized incidence rate (ASR) was the highest, serous carcinoma and adenocarcinoma were the major types and accounted for 27.4% and 17.9%, respectively. The USA, Brazil, Italy and Australia had a comparatively high incidence rate (7.7–9.2 per 100 000), behind the UK (12.6), and in those countries except for Brazil, the major morphology was serous carcinoma (33.1–43.2%) and the second major one was adenocarcinoma (12.4–17.0%), in common with the UK. In Brazil, the major morphology was adenocarcinoma (26.7%) and the second major one was serous carcinoma (18.8%), even though the proportion of unspecified morphology was the highest (24.7%) in comparison with those in the other countries (9.7–20.0%). It might be difficult in Brazil to diagnose the detail of morphology and this difficulty might cause adenocarcinoma to be major, which means that serous, mucinous endometrioid and clear cell carcinoma would be included in adenocarcinoma without detailed diagnosis. The incidence rates in Japan and the Republic of Korea were low compared with the other countries studied. In those countries, the most common morphology was also serous carcinoma (22.9% in Japan and 35.8% in Korea); however, the second most common morphology was clear cell carcinoma (13.7%) in Japan and mucinous carcinoma (13.1%) in Korea. In these two countries, adenocarcinoma accounted for 13.5% in Japan, which was as common as clear cell carcinoma, but it accounted for only 7.1% in Korea.