There are occasional conversations about the possibility of looking at a man’s fingers and predicting the aggressiveness of their prostate cancer. Is this real science or is this voodoo science? This might actually be real science!
During gestation a male fetus’s development of the prostate gland is dependent on a functional androgen receptor and the presence of dihydrotestosterone. Prenatal androgen exposure has been correlated with a range of diseases including prostate cancer (PCa).
Historically, the ratio of the second to the fourth digit (2D:4D) has been linked to prenatal androgen levels; however, the use of alternate finger ratios have been shown to be a greater indicator of prenatal androgen exposure compared to the traditional 2D:4D ratio. There have been studies that have shown that the distal fingertip extent of the second digit (2T:2D) was also associated with prenatal androgen exposure.
Researchers used alternative digit ratio measurements to determine aggressiveness of PCa. They assumed that alternative digit ratios are more sensitive to prenatal androgen levels, and a better predictor of disease than the traditional 2D:4D ratio.
They took digital measurements from hand scans of PCa patients. All fingers on the right hand were measured from the basal crease to the fingertip as well as the distal fingertip extent of the second digit. Race, family history (FH) (first degree relatives with PCa), and age at diagnosis were also recorded. These clinical covariates were then compared to the finger length ratios that were dichotomized based on the median values and analyzed for possible correlations.
They took measurements of 350 Caucasian (CA) and 100 African American (AA) PCa patients. AA men were more likely to have a smaller 2D:3D (P < 0.0001) and 2D:4D digit ratio (P < 0.0001), and larger 3D:5D (P = 0.0002) and 4D:5D (P = 0.0125) when compared to CA men. AA men with a smaller 2T:2D ratio were younger at the time of diagnosis (P = 0.0446). Additionally, AA men with a larger 2D:5D ratio were more likely to have a FH of PCa (P= 0.0238).
They concluded that alternative finger length ratios show strong differences between AA and CA men. In AA men, alternative digit ratios are associated with age of PCa diagnosis and FH of PCa.
What is the value of this study, perhaps it provides us with some insight to the underlying racial disparity we see in prostate cancer . Finger length may represent a unique, non-invasive predictor of PCa, specifically age of onset and FH in AA men.
J Clin Oncol 32, 2014 (suppl 4; abstr 231); Michael Stolten, Elisa Ledet, Aryeneesh Dotiwala, Eric Luk, A. Oliver Sartor, Byron Wood; Tulane University School of Medicine, New Orleans, LA; Tulane Cancer Center, New Orleans, LA
Joel T. Nowak, M.A., M.S.W.