“…Sixteen epidemiological studies have investigated the effect of tobacco smoking on HL (Hammond and Horn, 1958;Newell et al, 1973;Paffenbarger Jr et al, 1977;Williams and Horm, 1977;Abramson et al, 1978;Matthews et al, 1984;Bernard et al, 1987;McLaughlin et al, 1995;Siemiatycki et al, 1995;Adami et al, 1998;Miligi et al, 1999;Stagnaro et al, 2001;Briggs et al, 2002;Gallus et al, 2004;Glaser et al, 2004;Nieters et al, 2005). Out of the 11 reporting an increased risk (Hammond and Horn, 1958;Paffenbarger Jr et al, 1977;Williams and Horm, 1977;Matthews et al, 1984;McLaughlin et al, 1995;Siemiatycki et al, 1995;Adami et al, 1998;Stagnaro et al, 2001;Briggs et al, 2002;Glaser et al, 2004;Nieters et al, 2005), three presented significant results (McLaughlin et al, 1995;Briggs et al, 2002;Nieters et al, 2005), among which one is part of our research (Nieters et al, 2005).…”