Cancer Causes & Control

, Volume 20, Issue 5, pp 663–670 | Cite as

Season of diagnosis and prognosis in breast and prostate cancer

  • Lars HolmbergEmail author
  • Jan Adolfsson
  • Lorelei Mucci
  • Hans Garmo
  • Hans Olov Adami
  • Henrik Möller
  • Jan-Erik Johansson
  • Meir Stampfer
Original Paper



Patients with breast or prostate cancer diagnosed during the summer season have been observed to have better survival. The extent to which this is due to biological and/or health care system related factors is unclear.


Using the Swedish Cancer Register and clinical databases, we analyzed overall survival by month of diagnosis among the incident cases of breast (n = 89,630) cancer and prostate (n = 72,375) cancer diagnosed from 1960 to 2004. We retrieved data on tumor stage from 1976 for breast cancer and 1997 for prostate cancer. Cox proportional hazards models were used to calculate relative risk of survival by the season of diagnosis.


There was a higher hazard ratio of death in men and women diagnosed with cancer in the summer with a relative hazard of 1.20 (95% confidence interval 1.15–1.25) for July for prostate cancer and 1.14 (95% confidence interval 1.09–1.19) for August for breast cancer when compared to being diagnosed in January. This difference coincided with a lower mean number of cases diagnosed per day, and a higher proportion of advanced cases diagnosed in the summer. This pattern of presentation was stronger in the later years.


The difference in stage distribution explains the seasonal variation in prognosis seen in this study. The variation may be because of structure of the health care system and a strong tradition of vacationing from mid June to mid August. Thus, the health care infrastructure and the late presentation of symptomatic disease may influence cancer survival studied by season of diagnosis substantially.


Breast cancer Prostate cancer Prognosis Season of diagnosis Early diagnosis 



The study was supported by the Swedish Cancer Society. The clinical databases were collected and quality assured by the regional working collaborative groups for breast and prostate cancer in the Stockholm–Gotland and the Uppsala–Örebro health care regions.


  1. 1.
    Lim HS, Roychoudhuri R, Peto J, Schwartz G, Baade P, Möller H (2006) Cancer survival is dependent on season of diagnosis and sunlight exposure. Int J Cancer 119:1530–1536. doi: 10.1002/ijc.22052 PubMedCrossRefGoogle Scholar
  2. 2.
    Porojnicu A, Robsahm TE, Berg JP, Moan J (2007) Season of diagnosis is a predictor of cancer survival. Sun-induced vitamin D may be involved: a possible role of sun-induced vitamin D. J Steroid Biochem Mol Biol 103:675–678. doi: 10.1016/j.jsbmb.2006.12.031 PubMedCrossRefGoogle Scholar
  3. 3.
    Porojnicu AC, Lagunova Z, Robsahm TE, Berg JP, Dahlback A, Moan J (2007) Changes in risk of death from breast cancer with season and latitude: sun exposure and breast cancer survival in Norway. Breast Cancer Res Treat 102:323–38 (Epub 2006 Sept 21). doi: 10.1007/s10549-006-9331-8 Google Scholar
  4. 4.
    Robsahm TE, Tretli S, Dahlback A, Moan J (2004) Vitamin D3 from sunlight may improve the prognosis of breast-, colon- and prostate cancer (Norway). Cancer Causes Control 15:149–158. doi: 10.1023/B:CACO.0000019494.34403.09 PubMedCrossRefGoogle Scholar
  5. 5.
    Zhou W, Suk R, Liu G, Park S, Neuberg DS, Wain JC, Lynch TJ, Giovannucci E, Christiani DC (2005) Vitamin D is associated with improved survival in early-stage non-small cell lung cancer patients. Cancer Epidemiol Biomarkers Prev 14:2303–2309. doi: 10.1158/1055-9965.EPI-05-0335 PubMedCrossRefGoogle Scholar
  6. 6.
    Moan J, Porojnicu AC, Robsahm TE, Dahlback A, Juzeniene A, Tretli S, Grant W (2005) Solar radiation, vitamin D and survival rate of colon cancer in Norway. J Photochem Photobiol B 78:189–193. doi: 10.1016/j.jphotobiol.2004.11.004 PubMedCrossRefGoogle Scholar
  7. 7.
    Porojnicu AC, Robsahm TE, Ree AH, Moan J (2005) Season of diagnosis is a prognostic factor in Hodgkin’s lymphoma: a possible role of sun-induced vitamin D. Br J Cancer 93:571–574. doi: 10.1038/sj.bjc.6602722 PubMedCrossRefGoogle Scholar
  8. 8.
    Schwartz GG, Skinner HG (2007) Vitamin D status and cancer: new insights. Curr Opin Clin Nutr Metab Care 10:6–11PubMedGoogle Scholar
  9. 9.
    Giovannucci E (2005) The epidemiology of vitamin D and cancer incidence and mortality: a review (United States). Cancer Causes Control 16:83–95. doi: 10.1007/s10552-004-1661-4 PubMedCrossRefGoogle Scholar
  10. 10.
    Bouillon R, Eelen G, Verlinden L, Mathieu C, Carmeliet G, Verstuyf A (2006) Vitamin D and cancer. J Steroid Biochem Mol Biol 102:156–162. doi: 10.1016/j.jsbmb.2006.09.014 PubMedCrossRefGoogle Scholar
  11. 11.
    Meltzer AA, Annegers JF (1995) Survival time and season-of-treatment initiation in children with acute lymphoblastic leukaemia. Leuk Lymphoma 17:443–447. doi: 10.3109/10428199509056855 PubMedCrossRefGoogle Scholar
  12. 12.
    Sankila R, Joensuu H, Pukkala E, Toikkanen S (1993) Does the month of diagnosis affect survival of cancer patients? Br J Cancer 67:838–841PubMedGoogle Scholar
  13. 13.
    Aaltomaa S, Lipponen P, Eskelinen M (1992) Demographic prognostic factors in breast cancer. Acta Oncol 31:635–640. doi: 10.3109/02841869209083845 PubMedCrossRefGoogle Scholar
  14. 14.
    Porojnicu AC, Robsahm TE, Dahlback A, Berg JP, Christiani D, Bruland OS, Moan J (2007) Seasonal and geographical variations in lung cancer prognosis in Norway: does Vitamin D from the sun play a role? Lung Cancer 55:263–270. doi: 10.1016/j.lungcan.2006.11.013 PubMedCrossRefGoogle Scholar
  15. 15.
    Hebert-Croteau N, Brisson J, Pineault R (2000) Review of organizational factors related to care offered to women with breast cancer. Epidemiol Rev 22:228–238PubMedGoogle Scholar
  16. 16.
    Purushotham AD, Pain SJ, Miles D, Hamett A (2001) Variations in treatment and survival in breast cancer. Lancet Oncol 2:719–725. doi: 10.1016/S1470-2045(01)00585-X PubMedCrossRefGoogle Scholar
  17. 17.
    Barlow L, Westergren K, Holmberg L, Talbäck M (2008) The completeness of the Swedish Cancer Register—a sample survey for year 1998. Acta Oncol. doi: 10.1080/02841860802247664
  18. 18.
    Sandblom G, Holmberg L, Damber JE, Hugosson J, Johansson JE, Lundgren R, Mattsson E, Varenhorst E (2002) Prostate-specific antigen for prostate cancer staging in a population-based register. Scand J Urol Nephrol 36:99–105. doi: 10.1080/003655902753679373 PubMedCrossRefGoogle Scholar
  19. 19.
    Swedish Organised Service Screening Evaluation Group (2006) Reduction in breast cancer mortality from organized service screening with mammography: 1. Further confirmation with extended data. Cancer Epidemiol Biomarkers Prev 5:45–51. doi: 10.1158/1055-9965.EPI-05-0349 CrossRefGoogle Scholar
  20. 20.
    Ihaka R, Gentleman RR (1996) A language for data analysis and graphics. J Comput Graph Stat 5:299–314. doi: 10.2307/1390807 CrossRefGoogle Scholar
  21. 21.
    Autier P, Gandini S (2007) Vitamin D supplementation and total mortality. A meta-analysis of randomized controlled trials. Arch Intern Med 167:1730–1737. doi: 10.1001/archinte.167.16.1730 PubMedCrossRefGoogle Scholar

Copyright information

© Springer Science+Business Media B.V. 2008

Authors and Affiliations

  • Lars Holmberg
    • 1
    • 2
    Email author
  • Jan Adolfsson
    • 3
  • Lorelei Mucci
    • 4
    • 5
  • Hans Garmo
    • 1
    • 2
  • Hans Olov Adami
    • 5
  • Henrik Möller
    • 2
  • Jan-Erik Johansson
    • 6
  • Meir Stampfer
    • 4
    • 5
  1. 1.Regional Oncologic Center and Department of Surgical SciencesUppsala UniversityUppsalaSweden
  2. 2.Division of Cancer Studies, Medical SchoolKing’s College LondonLondonUK
  3. 3.Oncologic CenterCLINTEC, Karolinska InstituteStockholmSweden
  4. 4.Channing Laboratory, Department of MedicineBrigham and Women’s Hospital and Harvard Medical SchoolBostonUSA
  5. 5.Department of EpidemiologyHarvard School of Public HealthBostonUS
  6. 6.Center for Assessment of Medical TechnologyÖrebro University HospitalÖrebroSweden

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