Obesity linked to aggressive prostate cancer regardless of race
MedWire News: Obesity is associated with recurring prostate cancer in Black and White men, and is not more influential in either race, report US researchers.
“We observed that, regardless of race, obesity was associated with an increased risk for biochemical progression after radical prostatectomy. Thus, obesity appears to be related to aggressive disease regardless of race,” say Stephen Freeland (Duke University School of Medicine in Durham, North Carolina, USA) and team.
Their study examined the association between body mass index (BMI) and adverse clinical and pathologic outcomes, as well as risk for biochemical disease progression after radical prostatectomy (RP) in Black and White men.
Using data from the Shared Equal Access Regional Cancer Hospital (SEARCH) database, retrospective analysis was carried out on 1415 men (53% White) who had undergone RP and the results were stratified by race.
Adverse pathologic outcomes included a Gleason score of 7 or higher, the presence of positive surgical margins at RP, extraprostatic extension, and seminal vesicle invasion. Biochemical progression was defined as a single prostate-specific antigen (PSA) concentration higher than 0.2 ng/ml, two consecutive concentrations at 0.2 ng/ml, or secondary treatment for an elevated postoperative PSA level.
As published in the journal Cancer, the results show that after adjusting for pre-operative clinical characteristics, a high BMI (35 kg/m2 and above) was significantly associated with high tumor grade and positive surgical margins in White men. This trend was also noted in Black men but was not statistically significant.
The researchers found that neither high BMI nor race was significantly associated with any of the mentioned adverse pathologic features.
Among the White participants, 30% developed recurrent disease, compared with 35% of the Black participants. Among the whole cohort, Black men had a 1.27-fold increased risk for PSA progression compared with White men.
After adjusting results for pre-operative clinical characteristics, BMI was found to be associated with an increased risk for biochemical recurrence in both Black and White men . After further adjustment for multiple pathologic variables, a significantly increased risk for biochemical recurrence was also observed.
However, neither set of results showed a significant association between race and BMI for predicting biochemical progression.
“The current results indicate that obesity portends a poor prognosis regardless of race. Moreover, the associations between obesity and pathologic findings were more or less similar in both races,” the researchers conclude.
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By Sarah Guy