Risk of breast cancer among Norwegian women with visual impairment


Experimental studies suggest that melatonin has a protective effect against breast cancer. Exposure to light suppresses melatonin secretion, but to a lesser degree in totally blind persons. Breast cancer was investigated in a cohort of 15 412 Norwegian visually impaired women. The risk among totally blind women was 0.64 (95% CI = 0.21–1.49, 5 cases only), and for those who became blind before age of 65, the SIR was 0.51 (95% CI = 0.11–1.49). Our findings give support to the ‘melatonin hypothesis’. © 2001 Cancer Research Campaign http://www.bjcancer.com

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  1. Baldwin WS and Barrett JC (1998) Melatonin: receptor-mediated events that may affect breast and other steroid hormone-dependent cancers. Review. Mol Carcinog 21: 149–155

  2. Bernstein L and Ross RK (1993) Endogenous hormones and breast cancer risk. Review. Epidemiol Rev 15: 48–65

  3. Coleman MP and Reiter RJ (1992) Breast cancer, blindness and melatonin. Eur J Cancer 28: 501–503

  4. Feychting M, Osterlund B and Ahlbom A (1998) Reduced cancer incidence among the blind. Epidemiology 9: 490–494

  5. Hahn RA (1991) Profound bilateral blindness and the incidence of breast cancer. Epidemiology 2: 208–210

  6. Hansen E, Falch B and Quale GA (1996). Det Norske Blindekartotek 1968–1995. Oslo, (In Norwegian)

  7. Henderson BE, Ross R and Bernstein L (1988) Estrogens as a cause of human cancer: the Richard and Hinda Rosenthal Foundation Award lecture. Cancer Res 48: 246–253

  8. Key TJ and Pike MC (1988) The role of oestrogens and progestagens in the epidemiology and prevention of breast cancer. Review. Eur J Cancer Clin Oncol 24: 29–43

  9. Kvåle G, Heuch I and Eide GE (1987) A prospective study of reproductive factors and breast cancer. I. Parity. Am J Epidemiol 126: 831–841

  10. Lewy AJ, Wehr TA, Goodwin FK, Newsome DA and Markey SP (1980) Light suppresses melatonin secretion in humans. Science 210: 1267–1269

  11. Liburdy RP, Sloma TR, Sokolic R and Yaswen P (1993) ELF magnetic fields, breast cancer, and melatonin: 60 Hz fields block melatonin’s oncostatic action on ER+ breast cancer cell proliferation. J Pineal Res 14: 89–97

  12. MacMahon B, Lin TM, Lowe CR, Mirra AP, Ravnihar B, Salber EJ, Trichopoulos D, Valaoras VG and Yuasa S (1970) Age at first birth and cancer of the breast. A summary of an international study. Bull World Health Organ 43: 209–221

  13. Mevissen M, Lerchl A, Szamel M and Loscher W (1996) Exposure of DMBA-treated female rats in a 50-Hz, 50 microTesla magnetic field: effects on mammary tumor growth, melatonin levels, and T lymphocyte activation. Carcinogenesis 17: 903–910

  14. Narito T and Kudo H (1985) Effect of melatonin on B16 melanoma growth in athymic mice. Cancer Res 45: 4175–4177

  15. Preston DL, Lubin JH, Pierce D and McConney M (1993). Epicure. Seattle, HiroSoft International

  16. Stevens RG (1987) Electric power use and breast cancer: a hypothesis. Am J Epidemiol 125: 556–561

  17. Stevens RG and Davis S (1996) The melatonin hypothesis: electric power and breast cancer. Environ Health Perspect 104: 135–140

  18. Tamarkin L, Cohen M and Roselle D (1981) Melafouronin inhibition and pinealectomy enhancement of 7,12-dimethylbenz(a)anthracene-induced mammary tumors in the rat. Cancer Res 41: 4432–4461

  19. Tamarkin L, Baird CJ and Almeida OFX (1985) Melatonin: a coordinating signal for mammalian reproduction?. Science 227: 714–720

  20. Trichopoulos D, MacMahon B and Cole P (1972) Menopause and breast cancer risk. J Natl Cancer Inst 48: 605–613

  21. Verkasalo PK, Pukkala E, Stevens RG, Ojamo M and Rudanko SL (1999) Inverse association between breast cancer incidence and degree of visual impairment in Finland. Br J Cancer 80: 1459–1460

  22. World Health Organization (1980). International Classification of Impairments, Disabilities and Handicaps. A Manual of Classification Relating to Consequences of Disease. Geneva, World Health Organization

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Kliukiene, J., Tynes, T. & Andersen, A. Risk of breast cancer among Norwegian women with visual impairment. Br J Cancer 84, 397–399 (2001). https://doi.org/10.1054/bjoc.2000.1617

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  • blindness
  • visual impairment
  • breast cancer
  • melatonin

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