INCREASED RISK OF HEPATOBLASTOMA AMONG IMMATURE CHILDREN WITH A LOWERBIRTH-WEIGHT

Hepatoblastomas among children with very low birth weights have signif icantly increased recently, according to the data from the Japan Child ren's Cancer Registry for the Sears 1985-1993, We then analyzed more R egistry data for 1969-1994 to clarify the possible relationship betwee n low birth weight and hepatoblastoma. The percentage of low birth wei ghts was compared between 543 hepatoblastoma children in the Registry and all live births in Japan in four successive periods during the 26 years from 1969 to 1994, in relation to the given birth year. The perc entage of children with birth weights of 1500-1999 g among hepatoblast omas was higher, at 2.94-1.60%, than that among all live births in eac h of the four periods (0.79-0.92%), and the percentage of children wit h birth weights of 2000-2499 g was slightly higher. The percentage of children with birth weights of <1500 g and, especially, <1000 g, has i ncreased rapidly among children born after 1988 (1.60 and 6.40%, respe ctively), when most very low birth weight infants began to survive. Co mpared with children with a birth weight of 2500 g or more, the relati ve risks of hepatoblastoma among children with birth weights of <1000, 1000-1499, 1500-1999, and 2000-2499 g were 15.64 (P < 0.001), 2.53 (P = 0.129), 2.71 (P = 0.001), and 1.21 (P = 0.381), respectively, sugge sting the lon.er the birth weight, the higher the risk of hepatoblasto ma. There was no association between hepatoblastomas with a low birth weight and either age at diagnosis or congenital malformations or ligh t-for-date weight. The risk of hepatoblastoma for ion birth weight chi ldren may be inherently high, especially for lon er birth weights, and the recent rapid increase may be a result of an increase in the numbe r of more immature infants with a more sensitive liver and also more f requent exposure to risk factors related to perinatal treatment.