Saverio Caini1, Maria Sofia Cattaruzza2, Benedetta Bendinelli3, Giulio Tosti4, Giovanna Masala3, Patrizia Gnagnarella5, Melania Assedi3, Ignazio Stanganelli6, Domenico Palli3, Sara Gandini5. 1. Cancer Risk Factors and Lifestyle Epidemiology Unit, Cancer Research and Prevention Institute (ISPO), Via delle Oblate 2, 50139, Florence, Italy. s.caini@ispo.toscana.it. 2. Department of Public Health and Infectious Diseases, Faculty of Medicine, Policlinico Umberto I, "Sapienza" University, Rome, Italy. 3. Cancer Risk Factors and Lifestyle Epidemiology Unit, Cancer Research and Prevention Institute (ISPO), Via delle Oblate 2, 50139, Florence, Italy. 4. Division of Dermatoncological Surgery, European Institute of Oncology, Milan, Italy. 5. Division of Epidemiology and Biostatistics, European Institute of Oncology, Milan, Italy. 6. Skin Cancer Unit, Scientific Institute of Romagna for the Study and Treatment of Cancer, IRCSS, IRST, Meldola, Italy.
Abstract
PURPOSE: Laboratory studies suggested that caffeine and other nutrients contained in coffee and tea may protect against non-melanoma skin cancer (NMSC). However, epidemiological studies conducted so far have produced conflicting results. METHODS: We performed a literature review and meta-analysis of observational studies published until February 2016 that investigated the association between coffee and tea intake and NMSC risk. We calculated summary relative risk (SRR) and corresponding 95 % confidence intervals (95 % CI) by using random effects with maximum likelihood estimation. RESULTS: Overall, 37,627 NMSC cases from 13 papers were available for analysis. Intake of caffeinated coffee was inversely associated with NMSC risk (SRR for those in the highest vs. lowest category of intake: 0.82, 95 % CI 0.75-0.89, I 2 = 48 %), as well as intake of caffeine (SRR 0.86, 95 % CI 0.80-0.91, I 2 = 48 %). In subgroup analysis, these associations were limited to the basal cell cancer (BCC) histotype. There was no association between intake of decaffeinated coffee (SRR 1.01, 95 % CI 0.85-1.21, I 2 = 0) and tea (0.88, 95 % CI 0.72-1.07, I 2 = 0 %) and NMSC risk. There was no evidence of publication bias affecting the results. The available evidence was not sufficient to draw conclusions on the association between green tea intake and NMSC risk. CONCLUSIONS: Coffee intake appears to exert a moderate protective effect against BCC development, probably through the biological effect of caffeine. However, the observational nature of studies included, subject to bias and confounding, suggests taking with caution these results that should be verified in randomized clinical trials.
PURPOSE: Laboratory studies suggested that caffeine and other nutrients contained in coffee and tea may protect against non-melanoma skin cancer (NMSC). However, epidemiological studies conducted so far have produced conflicting results. METHODS: We performed a literature review and meta-analysis of observational studies published until February 2016 that investigated the association between coffee and tea intake and NMSC risk. We calculated summary relative risk (SRR) and corresponding 95 % confidence intervals (95 % CI) by using random effects with maximum likelihood estimation. RESULTS: Overall, 37,627 NMSC cases from 13 papers were available for analysis. Intake of caffeinated coffee was inversely associated with NMSC risk (SRR for those in the highest vs. lowest category of intake: 0.82, 95 % CI 0.75-0.89, I 2 = 48 %), as well as intake of caffeine (SRR 0.86, 95 % CI 0.80-0.91, I 2 = 48 %). In subgroup analysis, these associations were limited to the basal cell cancer (BCC) histotype. There was no association between intake of decaffeinated coffee (SRR 1.01, 95 % CI 0.85-1.21, I 2 = 0) and tea (0.88, 95 % CI 0.72-1.07, I 2 = 0 %) and NMSC risk. There was no evidence of publication bias affecting the results. The available evidence was not sufficient to draw conclusions on the association between green tea intake and NMSC risk. CONCLUSIONS: Coffee intake appears to exert a moderate protective effect against BCC development, probably through the biological effect of caffeine. However, the observational nature of studies included, subject to bias and confounding, suggests taking with caution these results that should be verified in randomized clinical trials.
Authors: Mohammad Khalesi; David C Whiteman; Suhail A R Doi; Justin Clark; Michael G Kimlin; Rachel E Neale Journal: Cancer Epidemiol Biomarkers Prev Date: 2013-07-05 Impact factor: 4.254