title: Recreational Physical Activity and Differentiated Thyroid Cancer Risk: A Pooled Analysis of Two Case-Control Studies.
abstract: OBJECTIVE
  Physical activity has been hypothesized to influence cancer occurrence through several mechanisms. To date, its relation with thyroid cancer risk has been examined in relatively few studies. We pooled 2 case-control studies conducted in Cuba and Eastern France to assess the relationship between self-reported practice of recreational physical activity since childhood and thyroid cancer risk.
  
  
  METHODS
  This pooled study included 1,008 cases of differentiated thyroid cancer (DTC) matched with 1,088 controls (age range 9-35 and 17-60 years in the French and Cuban studies, respectively). Risk factors associated with the practice of recreational physical activity were estimated using OR and 95% CI. Logistic regressions were stratified by age class, country, and gender and were adjusted for ethnic group, level of education, number of pregnancies for women, height, BMI, and smoking status.
  
  
  RESULTS
  Overall, the risk of thyroid cancer was slightly reduced among subjects who reported recreational physical activity (OR = 0.8; 95% CI 0.5-1.0). The weekly frequency (i.e. h/week) seems to be more relevant than the duration (years).
  
  
  CONCLUSIONS
  Long-term recreational physical activity, practiced since childhood, may reduce the DTC risk. However, the mechanisms whereby the DTC risk decreases are not yet entirely clear.
authors: U1018, Centre d'Epidémiologie et de Santé des Populations (CESP), Institut National de la Santé et de la Recherche Médicale (INSERM), Villejuif, France; Institut Gustave Roussy, Villejuif, France; Université Paris-Saclay, Villejuif, France.
authors: Constance
authors: C
authors: Xhaard
authors: National Institute of Oncology and Radiobiology (INOR), Havana, Cuba.
authors: Juan J
authors: JJ
authors: Lence-Anta
authors: U1018, Centre d'Epidémiologie et de Santé des Populations (CESP), Institut National de la Santé et de la Recherche Médicale (INSERM), Villejuif, France; Institut Gustave Roussy, Villejuif, France; Université Paris-Saclay, Villejuif, France.
authors: Yan
authors: Y
authors: Ren
authors: Groupement Hospitalier Lyon-Est, Hospices Civils de Lyon, Fédération d'Endocrinologie, Bron, France; Rhône-Alpes Thyroid Cancer Registry, Cancer Research Center of Lyon (UMR INSERM 1052, CNRS 5286), RTH Laennec Faculty of Medicine, University of Lyon, Lyon, France.
authors: Françoise
authors: F
authors: Borson-Chazot
authors: Rhône-Alpes Thyroid Cancer Registry, Cancer Research Center of Lyon (UMR INSERM 1052, CNRS 5286), RTH Laennec Faculty of Medicine, University of Lyon, Lyon, France.
authors: Geneviève
authors: G
authors: Sassolas
authors: Thyroid Cancer Registry of Champagne-Ardennes, Institut Jean Godinot, Reims, France.
authors: Claire
authors: C
authors: Schvartz
authors: Cancer Registry of Isère, Meylan, France.
authors: Marc
authors: M
authors: Colonna
authors: U1018, Centre d'Epidémiologie et de Santé des Populations (CESP), Institut National de la Santé et de la Recherche Médicale (INSERM), Villejuif, France; French National Registry of Childhood Solid Tumours, CHU, Nancy, France.
authors: Brigitte
authors: B
authors: Lacour
authors: Cancer Registry of Doubs, EA 3181, Université de Franche-Comté, Besançon, France.
authors: Arlette
authors: A
authors: Danzon
authors: Cancer Registry of Bas-Rhin, EA 3430, Faculty of Medicine, University of Strasbourg, Strasbourg, France.
authors: Michel
authors: M
authors: Velten
authors: U1018, Centre d'Epidémiologie et de Santé des Populations (CESP), Institut National de la Santé et de la Recherche Médicale (INSERM), Villejuif, France; Institut Gustave Roussy, Villejuif, France; Université Paris-Saclay, Villejuif, France.
authors: Enora
authors: E
authors: Clero
authors: U1018, Centre d'Epidémiologie et de Santé des Populations (CESP), Institut National de la Santé et de la Recherche Médicale (INSERM), Villejuif, France; Institut Gustave Roussy, Villejuif, France; Université Paris-Saclay, Villejuif, France.
authors: Stéphane
authors: S
authors: Maillard
authors: Cancer Registry of Haut-Rhin, Mulhouse Hospital, Mulhouse, France.
authors: Emilie
authors: E
authors: Marrer
authors: Public Health Department, University Hospital Nice, Nice, France.
authors: Laurent
authors: L
authors: Bailly
authors: Public Health Department, University Hospital Nice, Nice, France.
authors: Eugènia
authors: E
authors: Mariné Barjoan
authors: Institut Gustave Roussy, Villejuif, France.
authors: Martin
authors: M
authors: Schlumberger
authors: Department of Endocrinology, Hospices Civils de Lyon, Lyon, France.
authors: Jacques
authors: J
authors: Orgiazzi
authors: U1018, Centre d'Epidémiologie et de Santé des Populations (CESP), Institut National de la Santé et de la Recherche Médicale (INSERM), Villejuif, France; Université Paris-Saclay, Villejuif, France.
authors: Elisabeth
authors: E
authors: Adjadj
authors: National Institute of Oncology and Radiobiology (INOR), Havana, Cuba.
authors: Celia M
authors: CM
authors: Pereda
authors: National Institute of Endocrinology, Havana, Cuba.
authors: Silvia
authors: S
authors: Turcios
authors: National Institute of Oncology and Radiobiology (INOR), Havana, Cuba.
authors: Milagros
authors: M
authors: Velasco
authors: National Institute of Oncology and Radiobiology (INOR), Havana, Cuba.
authors: Mae
authors: M
authors: Chappe
authors: National Institute of Oncology and Radiobiology (INOR), Havana, Cuba.
authors: Idalmis
authors: I
authors: Infante
authors: National Institute of Oncology and Radiobiology (INOR), Havana, Cuba.
authors: Marlene
authors: M
authors: Bustillo
authors: National Institute of Oncology and Radiobiology (INOR), Havana, Cuba.
authors: Anabel
authors: A
authors: García
authors: National Institute of Oncology and Radiobiology (INOR), Havana, Cuba.
authors: Sirced
authors: S
authors: Salazar
authors: Cuban Public Health Ministry, Havana, Cuba.
authors: Regla
authors: R
authors: Rodriguez
authors: U1018, Centre d'Epidémiologie et de Santé des Populations (CESP), Institut National de la Santé et de la Recherche Médicale (INSERM), Villejuif, France; Institut Gustave Roussy, Villejuif, France; Université Paris-Saclay, Villejuif, France.
authors: Mohamed Amine
authors: MA
authors: Benadjaoud
authors: National Institute of Oncology and Radiobiology (INOR), Havana, Cuba.
authors: Rosa M
authors: RM
authors: Ortiz
authors: U1018, Centre d'Epidémiologie et de Santé des Populations (CESP), Institut National de la Santé et de la Recherche Médicale (INSERM), Villejuif, France; Institut Gustave Roussy, Villejuif, France; Université Paris-Saclay, Villejuif, France.
authors: Carole
authors: C
authors: Rubino
authors: U1018, Centre d'Epidémiologie et de Santé des Populations (CESP), Institut National de la Santé et de la Recherche Médicale (INSERM), Villejuif, France; Institut Gustave Roussy, Villejuif, France; Université Paris-Saclay, Villejuif, France.
authors: Florent
authors: F
authors: de Vathaire
keywords: Pooled case-control study; Recreational physical activity; Risk factors; Thyroid cancer