Childhood rhabdomyosarcoma in Ibadan, Nigeria: 1984-2003

Background: Rhabdomyosarcoma is the most common soft tissue sarcoma in children under 15 years of age. There is, however, a paucity of reports on the pattern of its occurrence in Nigeria and other parts of Africa. Aim: To describe the pattern of childhood rhabdomyosarcoma in Ibadan with respect to demography, morphology and tumour site. Methods: This retrospective study was based on data obtained from the Ibadan cancer registry, College of Medicine, University of Ibadan. All histologically confirmed cases of rhabdomyosarcoma in children under 15 years of age seen at the University College Hospital Ibadan between 1984 and 2003 were included. Information obtained includes age, gender, morphology and sites of the tumours. Results: Ninety-one children were seen with a male: female ratio of 1.5:1. Ages ranged from < 1 to 14 years with a mean (SD) of 6.2 (4.1) years. The embryonal variant was the most common histological subtype (61.5%). Other subtypes were alveolar (13.2%), pleomorphic (4.4%) and rhabdomyosarcoma 'not otherwise specified' (20.9%). The majority (50.6%) of tumours were in the head and neck region and the common primary sites were soft tissue of the head, face (24.2%) and orbit (14.3%). Other sites included soft tissue of the pelvis (11.0%), genito-urinary tract (9.9%) and abdomen (9.9%). Conclusion: The pattern of rhabdomyosarcoma in Nigeria is similar to that in the United States and Europe, except for the rarity of parameningeal sites and extremities. There is a need for larger descriptive studies on childhood rhabdomyosarcoma in Africa.