The condition is extremely rare, with less than 10 cases ever reported.

It is rare, with an incidence between 0.24 and 1.23 cases per million people.

Childhood cancer is relatively rare, with only around 1700 new cases a year up to age 15.

This condition is extremely rare with only two cases being found.

Type 4 is rare with only 48 cases reported up to 2002.

This tumor is rare, with several names used in the past.

It is also very rare, with fewer than 200 individuals known to live in Japan.

This condition is very rare, with only three cases in medical literature.

Murders are still rare, with one or two per year.

It's very rare for three or more single people to bond with each other all at the same time.