Non-Hodgkin lymphomaExposure to sunlight

  • The body of evidence supports the hypothesis that exposure to sunlight may reduce incidence of NHL
  • Several ecological studies have found that more exposure to sunlight is associated with lower rates of NHL
  • Some studies have failed to find this association, although this may be explained by use of sunscreens and protective clothing

There are a number of ecological studies on the relation between solar ultraviolet B (UVB) doses and NHL mortality rates. The earliest ecological study reported inverse correlations with latitude in the U.S., but failed to link the finding to vitamin D1, as did a later one2.

Subsequent ecological studies made the link to vitamin D345678.

There have been a number of case-control and cohort studies examining the association between solar UV doses and incidence of NHL. Many have found inverse correlations including in Australia910, Europe1110, Finland12, Greece13, Sweden1415, and the United States16

In a recent study from Scandinavia17, the joint roles of vitamin D receptor (VDR) genotypes (alleles) and ultraviolet irradiance were explored. There were indications that various types of NHL were affected by the combination of UV irradiance and VDR genotype, with some alleles associated with increased risk, others with decreased risk for higher UV irradiance. However, given that people do not know their VDR genotypes and that UV in Scandinavia has a lower ratio of UVB (290-315 nm) to UVA (315-400 nm), it is difficult to make any conclusions from this study.

A review of cancer incidence rates among outdoor workers in the U.K. found that higher rates of nonmelanoma skin cancer (NMSC) for males was significantly inversely correlated with NHL; females had lower NMSC rates than the rest of the population and a higher rate of NHL, although the inverse correlation was not statistically significant18.

A study in Greece found sun exposure associated with reduced risk of childhood NHL:

The estimated incidence of 10.2 cases per 1,000,000 children-years {95% Confidence Intervals (CI), 8.4-12.1} for NHL during the study period in Greece is around the average figure in countries of the European Union. There was an inverse association of sun exposure with NHL, namely, for an increment of 15 days of sunbathing at seaside resorts children had almost 40% lower risk (Odds Ratio: 0.60, 95% CI: 0.43-0.83), whereas no such association was evident for Hodgkin lymphoma13

On the other hand, there have been several observational studies that did not find a protective effect of UV irradiance such as two looking at occupational exposure, one in Australia19 and one in the United States20, summertime sun exposure in Connecticut21, and UV irradiance in Norway22

While the case can be made that UVB doses may be too low in Connecticut and Norway, the same can’t be made for Australia. On the other hand, outdoor workers may wear enough protective clothing that they do not produce much vitamin D in the sun. In Australia, people are strongly advised to wear hats and long sleeve shirts and sunscreen. 

A recent review found that the evidence that UV irradiance and vitamin D affect risk of Hodgkin lymphoma (HL) or non-Hodgkin lymphoma (NHL) was inconclusive23. However, this review did not consider all the evidence and did not try to resolve some of the conflicting results.

In summary, the preponderance of the evidence supports a protective role of ultraviolet radiation against NHL.

Note that ecological studies integrate the effect of cancer risk-modifying factors over the entire lifetime while observational studies are generally limited to 5-15 years of observation. There is evidence that the lag time between initiation and death from NHL can be 35 years or longer24. Thus, ecological studies should be particularly reliable.

Page last edited: 03 May 2011

References

  1. Hartge, P. Devesa, S. S. Grauman, D. Fears, T. R. Fraumeni, J. F., Jr. Non-Hodgkin’s lymphoma and sunlight. J Natl Cancer Inst. 1996 Mar 6; 88 (5): 298-300.
  2. Hu, S. Ma, F. Collado-Mesa, F. Kirsner, R. S. Ultraviolet radiation and incidence of non-Hodgkin’s lymphoma among Hispanics in the United States. Cancer Epidemiol Biomarkers Prev. 2004 Jan; 13 (1): 59-64.
  3. Boscoe, F. P. Schymura, M. J. Solar ultraviolet-B exposure and cancer incidence and mortality in the United States, 1993-2002. BMC Cancer. 2006; 6264.
  4. Grant, W. B. An estimate of premature cancer mortality in the U.S. due to inadequate doses of solar ultraviolet-B radiation. Cancer. 2002 Mar 15; 94 (6): 1867-75.
  5. Grant, W. B. Ecologic studies of solar UV-B radiation and cancer mortality rates. Recent Results Cancer Res. 2003; 164371-7.
  6. Grant, W. B. The likely role of vitamin D from solar ultraviolet-B irradiance in increasing cancer survival. Anticancer Res. 2006 Jul-Aug; 26 (4A): 2605-14.
  7. Grant, W. B. An ecologic study of cancer mortality rates in Spain with respect to indices of solar UVB irradiance and smoking. Int J Cancer. 2007 Mar 1; 120 (5): 1123-8.
  8. Grant, W. B. Garland, C. F. The association of solar ultraviolet B (UVB) with reducing risk of cancer: multifactorial ecologic analysis of geographic variation in age-adjusted cancer mortality rates. Anticancer Res. 2006 Jul-Aug; 26 (4A): 2687-99.
  9. Hughes, A. M. Armstrong, B. K. Vajdic, C. M. Turner, J. Grulich, A. E. Fritschi, L. Milliken, S. Kaldor, J. Benke, G. Kricker, A. Sun exposure may protect against non-Hodgkin lymphoma: a case-control study. Int J Cancer. 2004 Dec 10; 112 (5): 865-71.
  10. Kricker, A. Armstrong, B. K. Hughes, A. M. Goumas, C. Smedby, K. E. Zheng, T. Spinelli, J. J. De Sanjose, S. Hartge, P. Melbye, M. Willett, E. V. Becker, N. Chiu, B. C. Cerhan, J. R. Maynadie, M. Staines, A. Cocco, P. Boffeta, P. Personal sun exposure and risk of non Hodgkin lymphoma: a pooled analysis from the Interlymph Consortium. Int J Cancer. 2008 Jan 1; 122 (1): 144-54.
  11. Boffetta, P. van der Hel, O. Kricker, A. Nieters, A. de Sanjose, S. Maynadie, M. Cocco, P. L. Staines, A. Becker, N. Font, R. Mannetje, A. Goumas, C. Brennan, P. Exposure to ultraviolet radiation and risk of malignant lymphoma and multiple myeloma–a multicentre European case-control study. Int J Epidemiol. 2008 Oct; 37 (5): 1080-94.
  12. Lim, U. Freedman, D. M. Hollis, B. W. Horst, R. L. Purdue, M. P. Chatterjee, N. Weinstein, S. J. Morton, L. M. Schatzkin, A. Virtamo, J. Linet, M. S. Hartge, P. Albanes, D. A prospective investigation of serum 25-hydroxyvitamin D and risk of lymphoid cancers. Int J Cancer. 2009 Feb 15; 124 (4): 979-86.
  13. Petridou, E. T. Dikalioti, S. K. Skalkidou, A. Andrie, E. Dessypris, N. Trichopoulos, D. Sun exposure, birth weight, and childhood lymphomas: a case control study in Greece. Cancer Causes Control. 2007 Nov; 18 (9): 1031-7.
  14. Smedby, K. E. Hjalgrim, H. Melbye, M. Glimelius, B. Adami, H. O. Correspondence Re: Sun Exposure and Mortality From Melanoma. J Natl Cancer Inst. 2005 August 3; 97 (15): 1160-1.
  15. Smedby, K. E. Hjalgrim, H. Melbye, M. Torrang, A. Rostgaard, K. Munksgaard, L. Adami, J. Hansen, M. Porwit-MacDonald, A. Jensen, B. A. Roos, G. Pedersen, B. B. Sundstrom, C. Glimelius, B. Adami, H. O. Ultraviolet radiation exposure and risk of malignant lymphomas. J Natl Cancer Inst. 2005 Feb 2; 97 (3): 199-209.
  16. Kelly, J. L. Friedberg, J. W. Calvi, L. M. van Wijngaarden, E. Fisher, S. G. A case-control study of ultraviolet radiation exposure, vitamin D, and lymphoma risk in adults. Cancer Causes Control. 2010 Aug; 21 (8): 1265-75.
  17. Smedby KE, Eloranta S, Duvefelt K, Melbye M, Humphreys K, Hjalgrim H, Chang ET. Vitamin D Receptor Genotypes, Ultraviolet Radiation Exposure, and Risk of Non-Hodgkin Lymphoma. Am J Epidemiol. 2010 Nov; 12
  18. Newton, R. Roman, E. Fear, N. Carpenter, L. Non-Hodgkin’s lymphoma and solar ultraviolet radiation. Data are inconsistent. BMJ. 1996 Aug 3; 313 (7052): 298.
  19. Karipidis, K. K. Benke, G. Sim, M. R. Kauppinen, T. Kricker, A. Hughes, A. M. Grulich, A. E. Vajdic, C. M. Kaldor, J. Armstrong, B. Fritschi, L. Occupational exposure to ionizing and non-ionizing radiation and risk of non-Hodgkin lymphoma. Int Arch Occup Environ Health. 2007 Aug; 80 (8): 663-70.
  20. van Wijngaarden, E. Savitz, D. A. Occupational sunlight exposure and mortality from non-Hodgkin lymphoma among electric utility workers. J Occup Environ Med. 2001 Jun; 43 (6): 548-53.
  21. Zheng, T. Owens, P. H. Sunlight and non-Hodgkin’s lymphoma. Int J Cancer. 2000 Sep 15; 87 (6): 884-6.
  22. Veierod, M. B. Smedby, K. E. Lund, E. Adami, H. O. Weiderpass, E. Pigmentary characteristics, UV radiation exposure, and risk of non-Hodgkin lymphoma: a prospective study among Scandinavian women. Cancer Epidemiol Biomarkers Prev. 2010 Jun; 19 (6): 1569-76.
  23. Negri E. Sun exposure, vitamin D, and risk of Hodgkin and non-Hodgkin lymphoma. Nutr Cancer. 2010 Oct; 62 (7): 878-82.
  24. Richardson, D. B. Sugiyama, H. Wing, S. Sakata, R. Grant, E. Shimizu, Y. Nishi, N. Geyer, S. Soda, M. Suyama, A. Kasagi, F. Kodama, K. Positive associations between ionizing radiation and lymphoma mortality among men. Am J Epidemiol. 2009 Apr 15; 169 (8): 969-76.