Childhood brain tumors may cause symptoms that begin before diagnosis and continue for months or years.

Unexplained loss of more than 10% of body weight in the 6 months before diagnosis.

Symptoms caused by the tumor may begin before diagnosis.

About half the patients had autoantibodies for the disease an average of four and a half years before diagnosis.

Of those who did develop the disease, 88 percent had at least one autoantibody about 10 years before diagnosis.

The practitioner will need to have an overall picture before diagnosis; he/she may ask about your past illnesses, family tendencies or general energy levels.

Plasma selenium level before diagnosis and the risk of prostate cancer development.

The mean duration of symptoms before diagnosis was 9.1 (11.4) months.

All of these symptoms can occur years before diagnosis of the disease.

It is often associated with obesity and may be latent for some years before diagnosis.