The size of a cancerous prostate tumour is directly proportional to the weight of the patient and the bigger the tumour the more aggressive the cancer, a new study has found.
"As the patients' body mass index increased, the tumour volume increased synchronously," said Dr Nilesh Patil, who led the six-year study at Henry Ford Hospital in Detroit, Michigan.
"Based on our results, we believe having a larger percentage of tumour volume may be contributing to the aggressive nature of the disease in men with a higher BMI," he said.
The body mass index, or BMI, is calculated by dividing a person's weight by the square of his or her height.
The doctors established the relationship after analysing the cases of 3,327 patients who had cancerous prostate tumors surgical removed through a robotic procedure.
The subjects of the research were divided into six categories according to their BMI, with a rating of 24.9 considered normal or underweight, 25 to 29.9 overweight, 30 to 34.9 obese and 40 or higher extremely obese.
The patients' median age was 60 in all the categories.
The researchers weighed each tumour and compared them to a categorised database of prostate weight.
In each BMI category without exception, they found the patient's weight was in direct correlation with the size of the tumour. - (Sapa, June 2010)