Intrathyroidal hematopoiesis: a rare histological finding in an otherwise healthy patient and review of the literature

Abstract
Background and aims  Multinodular goiter represents the most common thyroid disease in Europe and the United States. Regressive changes like hemorrhage,
infarction or fibrosis are frequently observed. Calcifications have also been detected by microscopic investigation of thyroid
tissue. Extramedullary hematopoiesis has been described in almost every organ, especially in patients with hematologic diseases.
However, true bone formation is uncommon and to date only two cases of metaplastic bone formation with extramedullary hematopoiesis
in the thyroid have been reported in the literature.

Materials and Methods  We present a case of total thyroidectomy due to multinodular goiter harboring an area of mature bone and hematopoiesis in
an otherwise healthy female patient. Furthermore, we reviewed and summarized for the first time all available cases from the
literature.

Results  We report the third case of metaplastic bone formation with foci of hematopoietic tissue in the thyroid gland. All three patients
were young females without any obvious stimulus for extramedullary hematopoiesis.

Conclusion  Isolated extramedullary hematopoiesis seems to be more frequent in the thyroid gland than metaplastic bone formation with
hematopoiesis, particularly in older people with underlying hematologic disorders. It also represents an important differential
diagnosis of anaplastic carcinoma of the thyroid, particularly in intra-operative frozen sections and fine-needle aspiration
biopsy.

Content Type Journal ArticleCategory Case Management and Clinical ConsequencesDOI 10.1007/s00423-008-0299-1Authors
Christina C. Westhoff, University Hospital Giessen and Marburg GmbH, Medical Faculty Institute of Pathology Baldingerstraße 35043 Marburg GermanyElias Karakas, University Hospital Giessen and Marburg GmbH Department of Visceral-, Thoracic- and Vascular Surgery Marburg GermanyCarsten Dietz, University Hospital Giessen and Marburg GmbH Department of Visceral-, Thoracic- and Vascular Surgery Marburg GermanyPeter J. Barth, University Hospital Giessen and Marburg GmbH, Medical Faculty Institute of Pathology Baldingerstraße 35043 Marburg Germany

Journal Langenbeck's Archives of SurgeryOnline ISSN 1435-2451Print ISSN 1435-2443 (Source: Langenbeck's Archives of Surgery)