LETTER TO THE EDITOR Are Solid Tumours Different in Children with Down’s Syndrome? Daniel SATGE ´ 1 * , Annie J. SASCO 2 and Brigitte LACOUR 3 1 Laboratoire d’Anatomie Pathologique, Centre Hospitalier, Tulle, France 2 International Agency for Research on Cancer and Institut National de la Sante ´ et de la Recherche Me ´ dicale, Lyon, France 3 Registre National des Tumeurs Solides de l’Enfant, Faculte ´ de Me ´ decine, Nancy, France Dear Sir, A review of the literature showed a peculiar distribution of neoplasms in persons having Down’s syndrome (DS). It revealed a well-known increase in leukaemia combined with a less often described global decrease in solid neoplasms. It also found a difference in organ site and histology distribu- tion of solid neoplasms. 1 In adults this was confirmed in 3 subsequent epidemiologic studies on cancer incidence and on causes of death in DS conducted in Denmark, 2 Israel 3 and the United States, 4 showing a very low incidence of carci- nomas while germ cell tumours were more frequent than in the general population. However, for children 15 years of age, these studies could not provide sufficient data. The largest epidemiologic study reported only 7 cases of solid tumours in children 15 years in Great Britain. 5 To better know the tumour profile of children with DS, we conducted a retrospective study in France using the network of the Socie ´te ´ Franc ¸aise d’Oncologie Pe ´diatrique (SFOP), which covers the whole country. Our study was conducted through the centres of Paediatric Oncology covering, among the French metropolitan population of 58 million inhabitants, the 10.5 million 15 years of age. It aimed at gathering all cases of solid malignant tumours diag- nosed from 1980 onward in children with DS up to 14 years of age. We included teratomas, since these tumours can be either benign or malignant and their evolution is unpredictable, as well as all types of brain tumours. Each tumour was histolog- ically documented. A questionnaire requesting a listing of any encounter during clinical practice with patients having both DS and a solid tumour, as defined previously, was sent twice at 5-year intervals to every physician including radiologists and pathologists in each Paediatric Oncology centre. When a centre did not reply to our inquiry, physicians were contacted by phone. In case of a positive answer, a detailed clinical history was requested. This provided the basis for the computation of a number of observed cases. The number of expected cases of solid tumours in children with DS for the whole French pop- ulation was calculated on the basis of population rates of solid tumours in the total paediatric population obtained by the French Childhood Cancer Registry of Lorraine (CCRL) and extrapolated to the whole DS French paediatric population, taking into account the cumulative incidence of DS at birth (10.4 cases/10 000 births) and the survival proportion of DS at age 15 (76.6%). During the 22-year period of 1980 –2001, we could iden- tify 13 cases of solid tumours in children 15 years with DS (Table I), whereas 27.2 were expected (p = 0.007 based on Poisson distribution) based on the rates observed in CCRL and extrapolated to the whole French paediatric population with solid tumours (23,244 estimated cases). As a compar- ison, from 1990 –99, the annual number of incident cases of leukaemia in children with DS was about 10 new cases, according to the French National Registry of Childhood Leukaemia and Lymphomas, which covers the whole French paediatric population. These data confirm that solid tumours are less frequent in children with DS than in children of the general population and are much less frequent than leukaemia in DS. It also strengthens the idea of a peculiar distribution of solid tu- mours in DS. There was a complete lack of central nervous system (CNS) tumours, which usually account for one-third Grant sponsor: Ligue Nationale contre le Cancer, Comit´ e de la Corr` eze; Grant sponsor: Fondation J´ erˆ ome Lejeune. *Correspondence to: Laboratoire d’Anatomie Pathologique, Centre Hos- pitalier, Place Maschat 19012 Tulle, France. Fax: +33-555-29-86-05. E-mail: daniel.satge@ch-tulle.fr Received 5 November 2002; Revised 20 February 2003; Accepted 21 February 2003 DOI 10.1002/ijc.11212 TABLE I – OBSERVED CASES AND REPARTITION OF SOLID TUMOURS IN CHILDREN 15 YEARS OF AGE WITH DOWN’S SYNDROME IN FRANCE FROM 1980 –2001, AND EXPECTED CASES BASED ON THE FRENCH CHILDHOOD CANCER REGISTRY OF LORRAINE PERIOD 1983–97 AND EXTRAPOLATED TO THE WHOLE FRENCH PAEDIATRIC POPULATION Tumour type Children with Down’s syndrome Observed cases Expected cases Lymphomas 4 1 32% 5 19% CNS 2 tumours 0 — 9.1 35% Neuroblastoma 0 — 3 10% Retinoblastoma 2 3 15% 0.8 3% Wilms’ tumours 0 — 1.9 7% Other renal tumours 1 4 8% 0.2 1% Liver neoplasms 0 — 0.6 2% Bone tumours 0 — 1.9 7% Soft-tissue tumours 0 — 2.4 7% Germ cell tumours 5 5 37% 1.1 2% Carcinomas 1 6 8% 1.2 5% Other tumours 0 — 0 3% Total 13 27.2 1 Including 2 Hodgkin’s diseases.– 2 Central nervous system.– 3 1 bi- lateral, 1 unilateral.– 4 Clear cell renal sarcoma.– 5 2 retroperitoneal, 1 gastric, 2 testicular.– 6 1 case of multiple skin carcinomas. Int. J. Cancer: 106, 297–298 (2003) © 2003 Wiley-Liss, Inc. Publication of the International Union Against Cancer