Interleukin-6 has been implicated as a mediator of growth control in several human neoplasms including multiple myeloma (Hussein et al, 2002), prostatic cancer (Giri et al, 2001) and colonic cancer (Schneider et al, 2000) and elevation of serum IL-6 level have been reported in some cancers such as renal cell carcinoma (Blay et al, 1992), ovarian cancer (Plante et al, 1994), cholangiocarcinoma (Goydos et al, 1998) and pancreatic cancer (Barber et al, 1999). Here, IL6 is linked to Familial prostate cancer.