How much a man weighs has been directly linked to the size of his cancerous prostate tumor, according to the results from a six-year study at Henry Ford Hospital in Detroit, Mich.

Researchers say the bigger the tumor, the more aggressive the cancer may be. The findings were presented at the American Urological Association's annual meeting in Detroit.

"As the patients' body mass index increased, the tumor volume increased synchronously," said Dr. Nilesh Patil, a Ford urologist who led the six-year study at the hospital

"Based on our results, we believe having a larger percentage of tumor volume may be contributing to the aggressive nature of the disease in men with a higher BMI," he said.

Researchers studied more than 3,000 patients. They found that as a man's body mass index or BMI increased, so did the potential tumor volume.

Patil said he could not say weight control would prevent a recurrence of cancer in men already diagnosed with the disease. But he said weight control "always is a good idea" to maintain good health.

*The Detroit Free Press contributed to this report.