Discrepant outcomes in two Brazilian patients with Bloom syndrome and Wilms' tumor: two case reports.

Introduction: Bloom syndrome is a rare, autosomal recessive, chromosomal instability disorder caused by mutations in the BLM gene that increase the risk of developing neoplasias, particularly lymphomas and leukemias, at an early age.

Case Presentation: Case 1 was a 10-year-old Brazilian girl, the third child of a non-consanguineous non-Jewish family, who was born at 36 weeks of gestation and presented with severe intrauterine growth restriction. She had Bloom syndrome and was diagnosed with a unilateral Wilms' tumor at the age of 3.5 years. She responded well to oncological treatment and has remained disease-free for the last 17 years. Case 2 was a 2-year-old Brazilian girl born to non-Jewish first-degree cousins. Her gestation was marked by intrauterine growth restriction. She had Bloom syndrome; a unilateral stage II Wilms' tumor was diagnosed at the age of 4 years after the evaluation of a sudden onset abdominal mass. Surgical removal, neoadjuvant chemotherapy and radiotherapy were not sufficient to control the neoplasia. The tumor recurred after 8 months and she died from clinical complications.

Conclusion: Our study reports the importance of rapid diagnostics and clinical follow-up of these patients.