Increased Incidence of Breast Cancer Due to Long Exposure of Light


  • K. Pushkala S.D.N.B. Vaishnav College for Women, Chennai, India
  • P.D. Gupta Manipal University, Manipal, India



Blind women model, low incidence, photoperiod, melatonin, epidemiology.


 The disturbed circadian rhythm due to long exposure to varied photo periods or to artificial light during night time (LAN) results in hormonal imbalance. The epidemiological survey indicates a clear difference in the incidence of breast cancer (BC) in countries closer to the poles and to the equator. Long-term exposure to LAN during sleep cycle is found to be the root cause of many health problems. Light dependent conversion of melatonin from serotonin plays a major role in cancer development. In rat model it is shown that levels of melatonin are always inversely proportional to oestradiol in the blood. Melatonin decreases the formation of oestrogens (mitogenic hormone) from androgens via aromatise inhibition. In a pilot study we have shown that in menopausal blind (risk age for BC) women the prevalence of BC is very low (1:169; Risk Rate (RR); Cumulative Risk (CR)35-64 age), compared to sighted women (1:78; CR, 35 - 64 age). Data was collected from a total of 2060 blind subjects (18.8% being <40 years of age and 81.2% above 40 years). Partially blind subjects have 11% greater risk of developing BC than those who are totally blind (RR=1.106; 95% CI=.352 to 3.472). Other established risk factors for BC are ineffective in blind. The blind women model (proposed in this study) suggests that dark hours are essential in our daily routine. By management of proper circadian rhythms better management of various endocrine diseases including hormone dependent cancers can be achieved.


Stevens RG, Hansen J, Costa G, Haus E, Kauppinen T, Aronson KJ, Straif K. Considerations of circadian impact for defining “shift work” in cancer studies: IARC Working Group Report. Occup Environ Med 2011; 68: 154-62.

Brudnowska J, Pep?o?ska B. Night shift work and cancer risk: a literature review. Med Pr 2011; 62: 323-38.

Hansen J, Lassen CF. Nested case-control study of night shift work and breast cancer risk among women in the Danish military. Occup Environ Med 2012; 69: 551-56.

Hansen J, Stevens RG. Case-control study of shift-work and breast cancer risk in Danish nurses: Impact of shift systems. Eur J Cancer 2012; 48: 1722-9.

Kamdar BB, Tergas AI, Mateen FJ, Bhayani NH Oh J. Night-shift work and risk of breast cancer: a systematic review and meta-analysis. Breast Cancer Res Treat 2013; 138: 291-301.

Jia, Y, Lu Y, Wu K, Lin Q, Shen W, Zhu M, Huang S, Chen, J. Does night work increase the risk of breast cancer? A systematic review and meta-analysis of epidemiological studies. Cancer Epidemiol 2013; 37: 197-206.

Wang F, Yeung KL, Chan WC, Kwok CCH, Leung SL,Wu C, Chan WYY, Yu ITS, Yang XR, Tse, LA. A meta-analysis on dose-response relationship between night shift work and the risk of breast cancer. Ann Oncol 2013; 24: 2724-32.

He C, Anand ST, Ebell MH, Vena JE, Robb, SW.Circadian disrupting exposures and breast cancer risk: a meta-analysis. Int Arch Occup Environ Health 2015; 88: 533-47.

Koppes LL, Geuskens GA, Pronk A, Vermeulen RC, de Vroome, EM. Night work and breast cancer risk in a general population prospective cohort study in The Netherlands. Eur J Epidemiol 2014; 29: 577-84.

Stevens, RG, Brainard GC, Blask DE, Lockley SW, Motta, ME. Adverse health effects of night time lighting: comments on American Medical Association policy statement. Am J Prev Med 2013; 45: 343-6.

Hurley S, Goldberg D, Nelson D, Hertz A, Horn-Ross PL, Bernstein L. Reynolds P. Light at night and breast cancer risk among California teachers. Epidemiology 2014; 25: 697-06.

Menegaux F, Truong T, Anger A, Cordina-Duverger E, Lamkarkach F, Arveux P, Kerbrat P, Févotte J,Guénel, P. Night work and breast cancer: A population-based case-control study in France (the CECILE study). Int J Cancer 2013; 13: 924-31.

Tynes T, Hannevik M, Andersen A, Vistnes A, Haldorsen T. Incidence of breast cancer in Norwegian female radio and telegraph operators. Cancer Causes and Control 1996; 7: 197-204.

Hansen J. Light at Night, Shift work, and Breast Cancer Risk. J Natl Cancer Inst 2001; 93: 1513-15.

Pukkala E, Aspholm R, Auvinen A, Eliasch H, Gundestrup M, Haldorsen T, Hammar N, Hrafnkelsson J, Kyyrönen P, Linnersjö A, Rafnsson V, Storm H, Tveten, U. Cancer incidence among 10,211 airplane pilots: A Nordic study. Aviat Space Environ Med 2003; 74: 699-06.

Franzese E, Nigri, G. Night work as a possible risk factor for breast cancer in nurses. Correlation between the onset of tumors and alterations in blood melatonin levels. Prof Inferm 2007; 60: 89-93.

Viswanathan AN, Hankinson SE, Schernmmer ES. Night shift work and the risk of endometrial cancer. Cancer Res 2007; 67: 10618-22.

Blask DE, Brainard GC, Dauchy RT, Hanifin JP, Davidson LK, Krause JA, Sauer LA, Rivera-Bermudez MA, Dubocovich ML, Jasser SA, Lynch DT, Rollag MD, Zalatan F. Melatonin-depleted blood from premenopausal women exposed to light at night stimulates growth of human breast cancer xenografts in nude rats. Cancer Res 2005; 65: 11174-84.

Cos S, Sanchez-Barcelo, E. Melatonin and mammary pathological growth. Front Neuroendocrinol 2000; 21: 133-170.

Knower KC, To SQ, Takagi K, Miki Y, Sasano H, Simpson ER, Clyne CD. Melatonin suppresses aromatase expression and activity in breast cancer associated fibroblasts. Breast Cancer Res Treat 2012; 132: 765-71.

Hahn RA. Profound bilateral blindness and the incidence of breast cancer. Epidemiol 1991; 2: 208-10.

Feychting M, Osterlund B, Ahlbom, A. Reduced cancer incidence among the blind. Epidemiol 1998; 5: 490-94.

Verkasalo PK, Pukkala E, Stevens RG, Ojamo M, Rudanko, SL. Inverse association between breast cancer incidence and degree of visual impairment in Finland. Brit J Cancer 1999; 80: 1459-60.

Kliukiene J, Tynes T, Andersen A. Risk of breast cancer among Norwegian women with visual impairment. Brit J Cancer 2001; 84: 397-99.

Pukkala E, Ojamo M, Rudanko SL, Stevens RG, Verkasalo, PK. Does incidence of breast cancer and prostate cancer decrease with increasing degree of visual impairment? Cancer Causes and Control 2006; 17: 573-76.

Coleman MP, Reiter, RJ. Breast cancer, blindness and melatonin. Eur J Cancer 1992; 28: 501-3.

World Health Organization, 1980. 2. International Classification of Functioning, Disability and Health (Geneva: World Health Organization, 2001. ... -WHO/World Cancer Day. 4 February 2009. Cancer is a leading cause of death around the world. WHO estimates that 84 million people will die of cancer between 2005 ... mediacentre/ events/.../world_ cancer.../index.html

Shantha V, Swaminathan R, Nalini, Kavitha M. Population based cancer registry, Chennai Cancer Institute (WIA ...File Format: PDF/Adobe Acrobat - View as HTML Individual Registry Data: 2001- 2003. Chennai. 135.Cancer Institute (WIA), Adyar, Chennai. Registration area ... 53.pdf - Similar

Epi Info [computer program]. Version 3.3.2. Atlanta: Centers for Disease Control and Prevention 2005.

Yeole BB, Kurkure AP. An epidemiological assessment of increasing incidence and trends in breast cancer in Mumbai and other sites in India, during the last two decades. Asian Pac J Cancer Prev 2003; 4: 51-56.

Bagchi S. Breast cancer rises in India. Can Med Assoc J 2008; 179: 27.

Pushkala K, Gupta PD. Prevalence of breast cancer in menopausal blind Women. Int J Med Med Sci 2009; 1: 425-31.

Pushkala K, Gupta PD. Dark side of the night light Monograph. LAMBERT Academic Publishing, GmbH & Co. KG, Saarbrücken, Germany 2011; (123 Pages).

Gupta PD, Pushkala K. Prevention and Treatment of Breast Cancer by Light and Food In: Natural Products and their Active Compounds on Disease Prevention. Editors: Essa MM, Manickavasagan A, Sukumar E. Nova Science Publishers. C.G.C Press USA, 2012; 153-159.

Gupta PD, Usha N, Pushkala K. Dark side of the night light: Implication in breast cancer. J Cell Tissue Res 2010; 10: 2173-84.

Pushkala K, Gupta PD. Epigenetic Effect of Food for Cancer Management. Int J Med Sciences and Biotechnology 2013; 1: 1-11.

Shantha V, Swaminathan R, Balasubramanian S. Cancer incidence and mortality in Chennai-India: 2003-2005. National cancer registry Programme Cancer Institute (W.I.A.), Chennai 2008.

Pukkala E, Verkasalo PK, Ojamo M, Rudanko SL. Visual impairement and cancer: a population based cohort study in Finland. Cancer Causes and Control 1999; 10: 13-20.

Jagota A, Olcese J, Harinarayana Rao S, Gupta PD. Pineal rhythms are synchronized to light-dark cycles in congenitally anophthalmic mutant rats. Brain Res 1999; 825: 95-103.

Gammon MD, Eng SM, Teitelbaum SL, Britton JA, Kabat GC, Hatch M. Paykin AB, Neugut AI, Santella RM. Environmental tobacco smoke and breast cancer incidence. Environ Res 2004; 96: 176-85.

Detailed Guide: Breast Cancer; What Are the Risk Factors for Breast Cancer?. Copyright 2008 © American Cancer Society, Inc. [Revised: 09/13/2007]. Available from: ttp: //

Barnett GC, Shah M, Redman K, Easton DF, Ponder AJ, Pharoah PDP. Risk Factors for the Incidence of Breast Cancer: Do They Affect Survival From the Disease? J Clin Oncol 2008; 26: 3310-16.

Goodwin PJ. Host-Related Factors in Breast Cancer: An Under appreciated Piece of the Puzzle? J Clin Oncol 2008; 26: 3299-300.

Travis RC, Allen DS, Fentiman IS, Key TJ. Melatonin and Breast cancer: a prospective study. J Natl Cancer Inst 2004; 96: 475-82.

Hendry J. Being breast-fed may lower breast cancer risk. 2008; Print. Last Updated: 2008-05-09 12: 00: 24 -0400 (Reuters Health) 20080509.jsp).

Bernstein L, Cayla R, Teal MA, Sue Joslyn Jerome Wilson. Ethnicity-Related Variation in Breast Cancer Risk Factors Cancer 2003; 97: 222-9.

Gajalakshmi CK, Shanta V, Matti Hakama M. Risk factors for contra-lateral breast cancer in Chennai (Madras), India. Intern J Epidemiol 1998; 27: 743-50.




How to Cite

K. Pushkala, & P.D. Gupta. (2016). Increased Incidence of Breast Cancer Due to Long Exposure of Light. Journal of Analytical Oncology, 5(4),  146–152.