Table 1 Characteristics of the study cohort
| Â | First Primary Cancers | Second Primary Cancers | ||
|---|---|---|---|---|
N | % | N | % | |
Sex | ||||
 Males | 155,214 | 50.1 | 19,811 | 58.6 |
 Females | 154,899 | 49.9 | 13,982 | 41.4 |
Age at diagnosis | ||||
 15–49 years | 54,930 | 17.7 | 1250 | 3.7 |
 50–64 years | 93,939 | 30.3 | 6708 | 19.9 |
 65 years and over | 161,244 | 52.0 | 25,835 | 76.5 |
Period of diagnosis | ||||
 1981–1984 | 27,063 | 8.7 | 411 | 1.2 |
 1985–1989 | 39,184 | 12.6 | 1971 | 5.8 |
 1990–1994 | 47,624 | 15.4 | 3364 | 10.0 |
 1995–1999 | 57,764 | 18.6 | 4724 | 14.0 |
 2000–2004 | 67,145 | 21.7 | 6566 | 19.4 |
 2005–2009 | 71,333 | 23.0 | 8635 | 25.6 |
 2010–2014 | n.a* |  | 8122 | 24.0 |
Follow-up interval | ||||
 6 month to less than 1 year | n.a.** |  | 2098 | 6.2 |
 1 years to less than 5 years | n.a.** |  | 12,532 | 37.1 |
 5 years to less than 10 years | n.a.** |  | 10,011 | 29.6 |
 10 years and longer | n.a.** |  | 9152 | 27.1 |
Type of primary cancer | ||||
 Cavity & Pharynx (C00-C14) | 8465 | 2.7 | 1565 | 4.6 |
 Oesophagus (C15) | 3055 | 1.0 | 785 | 2.3 |
 Stomach (C16) | 7663 | 2.5 | 1056 | 3.1 |
 Colorectal (C18-C20) | 35,949 | 11.6 | 4353 | 12.9 |
 Extrahepatic Bile Ducts (C22) | 2780 | 0.9 | 768 | 2.3 |
 Pancreas (C25) | 4534 | 1.5 | 1267 | 3.7 |
 Larynx (C32) | 2575 | 0.8 | 367 | 1.1 |
 Lung (C33-C34) | 24,539 | 7.9 | 5152 | 15.2 |
 Melanoma (C43) | 17,794 | 5.7 | 1662 | 4.9 |
 Breast female (C50) | 59,453 | 19.2 | 2597 | 7.7 |
 Cervix uteri (C53) | 4080 | 1.3 | 125 | 0.4 |
 Corpus uteri & NOS (C54-C55) | 9710 | 3.1 | 876 | 2.6 |
 Ovary (C56) | 6067 | 2.0 | 530 | 1.6 |
 Prostate (C61) | 48,311 | 15.6 | 3694 | 10.9 |
 Testis (C62) | 4912 | 1.6 | 36 | 0.1 |
 Kidney (C64) | 6210 | 2.0 | 812 | 2.4 |
 Bladder (C67) | 9801 | 3.2 | 1387 | 4.1 |
 Brain & Central Nerves (C70-C72) | 4072 | 1.3 | 403 | 1.2 |
 Thyroid (C73) | 4360 | 1.4 | 414 | 1.2 |
 Hodgkin Lymphoma (C81) | 2481 | 0.8 | 123 | 0.4 |
 non-Hodgkin Lymphoma (C82-C86, C96) | 11,340 | 3.7 | 1301 | 3.8 |
 Multiple Myeloma (C90) | 4298 | 1.4 | 487 | 1.4 |
 Leukemia (C91-C95) | 7933 | 2.6 | 1062 | 3.1 |
 Others | 19,731 | 6.4 | 2971 | 8.8 |
All cancers | 310,113 | 100.0 | 33,793 | 100.0 |