Skin Tumours Skin and Mucosa

cancer฀ in฀ female฀ smokers.฀ Among฀ 2,569฀ women฀ with฀ histologically฀ conirmed฀ breast฀ ฀cancer,฀the฀odds฀ratios฀compared฀with฀women฀who฀had฀never฀smoked฀were฀0.84฀CI:฀ 0.7–1.0฀for฀current฀smokers฀and฀1.14฀CI:฀0.9–1.4฀for฀ex-smokers.฀There฀was฀also฀no฀ increase฀in฀cancer฀risk฀as฀a฀function฀of฀cigarettes฀smoked฀ [564] .฀Similar฀indings฀had฀already฀ been฀reported฀in฀an฀older฀US฀study฀in฀4,720฀women฀with฀breast฀cancer฀OR฀=฀1.2;฀CI:฀ 1.1–1.3฀ [565] .฀Comparison฀of฀the฀incidence฀of฀breast฀cancer฀as฀compared฀with฀that฀of฀lung฀ cancer฀over฀more฀than฀50฀years,฀the฀incidence฀of฀lung฀cancer฀was฀increased฀by฀multiples฀ over฀the฀same฀period฀cf.฀Fig.฀5.1฀in฀Chap.฀5. The฀California฀Environmental฀Protection฀Agency฀CalEPA฀completed฀a฀health฀effects฀ assessment฀of฀exposure฀to฀environmental฀tobacco฀smoke฀ETS฀which฀resulted฀in฀California฀ listing฀ETS฀as฀a฀toxic฀air฀contaminant฀in฀January฀2006.฀As฀part฀of฀the฀assessment,฀studies฀ on฀the฀association฀between฀exposure฀to฀ETS฀and฀breast฀cancer฀were฀reviewed.฀Miller฀et฀al.฀ analysed฀ 26฀ published฀ reports฀ including฀ three฀ meta-analyses฀ evaluating฀ the฀ data฀ and฀ reviewd฀the฀association฀between฀ETS฀exposure฀and฀breast฀cancer.฀A฀weight-of-evidence฀ approach฀ was฀ applied฀ to฀ evaluate฀ the฀ data฀ and฀ draw฀ conclusions฀ about฀ the฀ association฀ between฀ breast฀ cancer฀ and฀ ETS฀ exposure.฀ The฀ published฀ data฀ indicate฀ an฀ association฀ between฀ETS฀and฀breast฀cancer฀in฀younger฀primarily฀premenopausal฀women.฀Thirteen฀of฀ the฀14฀studies฀ten฀case-control฀and฀four฀cohort฀that฀allowed฀analysis฀by฀menopausal฀sta- tus฀reported฀elevated฀risk฀estimates฀for฀breast฀cancer฀in฀premenopausal฀women,฀seven฀of฀ which฀were฀statistically฀signiicant.฀Our฀meta-analyses฀indicated฀elevated฀summary฀rela- tive฀risks฀ranging฀from฀OR฀1.68฀95฀C.I.฀1.31,฀2.15฀for฀all฀14฀studies฀to฀2.20฀95฀C.I.฀ 1.69,฀2.87฀for฀those฀with฀the฀best฀exposure฀assessment.฀The฀CalEPA฀with฀its฀experts฀ concluded฀ that฀ regular฀ ETS฀ exposure฀ is฀ causally฀ related฀ to฀ breast฀ cancer฀ diagnosed฀ in฀ younger,฀primarily฀premenopausal฀women฀and฀that฀the฀association฀is฀not฀likely฀explained฀ by฀bias฀or฀confounding฀ [566] .

7.9 Haematopoietic System

Evidence฀indicating฀a฀possible฀association฀between฀smoking฀and฀the฀development฀of฀leukae- mia฀was฀not฀published฀until฀1986฀ [567] ,฀and฀subsequently฀this฀has฀been฀demonstrated฀not฀ only฀for฀leukaemias฀in฀children฀but฀also฀in฀adults฀ [568,฀569] .฀Several฀cohort฀studies฀ [570–572] ฀ and฀case–control฀studies฀ [568,฀573] ฀focussing฀on฀this฀issue฀have฀been฀published. Genetic฀ defects฀ in฀ NAT2฀ acetylation฀ [574] ฀ or฀ in฀ the฀ cytochrome฀ system฀ CYP1A1,฀ CYP2D6฀or฀CYP2C19฀ [575] ฀has฀no฀inluence฀on฀the฀development฀of฀acute฀myeloid฀or฀ lymphoblastic฀forms฀of฀leukaemia. Results฀published,฀to฀date,฀are฀highly฀contradictory,฀particularly฀because฀several฀studies฀ have฀ reported฀ no฀ association฀ between฀ smoking฀ and฀ leukaemia฀ [576–583] .฀ In฀ a฀ 20-year฀ ฀follow-up฀of฀more฀than฀17,500฀white฀males,฀compared฀with฀non-smokers,฀seasoned฀smokers฀ had฀an฀increased฀relative฀risk฀for฀lymphoblastic฀leukaemia฀RR฀=฀2.7฀and฀other฀unspeciied฀ leukaemia฀RR฀=฀1.5฀ [584] .฀Further฀studies฀have฀conirmed฀that฀smoking฀confers฀an฀increased฀ risk฀for฀various฀forms฀of฀leukaemia฀in฀adult฀men฀and฀women฀OR฀=฀1.5;฀CI:฀1.1–2.0฀and฀1.4;฀