Histologic Types of Thymoma Associated with Pure Red Cell Aplasia: A Study of Five Cases Including a Composite Tumor of Organoid Thymoma Associated with an Unusual Lipofibroadenoma

Abstract

The histologic type of thymomas associated with pure red cell aplasia (PRCA) has generally been regarded to be predominantly the spindle cell type. The 5 thymomas associated with PRCA we studied showed various histologic types and none of them was a spindle cell thymoma. Some cases reported as spindle cell thymoma associated with PRCA in the literature might not be spindle cell type. The discrepancy could be due to the lack of consensus in the histologic classification of thymomas in the past. Our study showed that thymomas associated with PRCA lacked a strong correlation with a particular histologic type and the pathogenesis of PRCA associated with thymoma did not seem to be related to the histologic type. One of our cases was an unusual composite tumor of an organoid thymoma (WHO type B1) and a hitherto undescribed “lipofibroadenoma.” The clinical outcome was influenced by the invasive character and the histologic type of the thymoma.

Keywords

thymoma pure red cell aplasia histologic type thymic lipofibroadenoma

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References

1. Rosenow III EC , Hurley BT . Disorders of the thymus. A review. Arch Intern Med 144:763-770, 1984

2. Erslev AJ , Soltan A . Pure red-cell aplasia: A review. Blood Reviews 10:20-28, 1996

3. Kuo T , Lo SK . Thymoma: A study of the pathologic classification of 71 cases with evaluation of the Miller-Hermelink system. Hum Pathol 24:766-771, 1993

4. Rosai J . Histological typing of tumours of the thymus. World Health Organization International Histological Classification of Tumours, 2nd ed. Springer Verlag, Berlin, 1999

5. Kuo T-t . Cytokeratin profiles of the thymus and thymomas: Histogenetic correlations and proposal for a histological classification of thymomas. Histopathology 36:403-414, 2000

6. Rosai J , Levine GD . Tumors of the thymus. Atlas of tumor pathology. Second series. Fascicle 13. Armed Forces Institute of Pathology, Washington, D.C., pp.137-138, 1976

7. Shimosato Y , Mukai K . Tumors of the mediastinum. Atlas of tumor pathology. Third series. Fascicle 21. Armed Forces Institute of Pathology, Washington, D.C., p.110-110, 1997

8. Masaoka A , Hashimoto T , Shibata K , Yamakawa Y , Nakamae K , lizuka M . Thymomas associated with pure red cell aplasia. Histologic and follow-up studies. Cancer 64:1872-1878, 1989

9. Hirst E , Robertson TI . The syndrome of thymoma and erythroblastopenic anemia. A review of 56 cases including 3 case reports. Medicine 46:225-264, 1967

10.

10. Bernatz PE , Harrison EG , Clagett OT . Thymoma: A clinicopathologic study. J Thorac Cardiovasc Surg 42:424-444, 1961

11.

11. Lattes R . Thymoma and other tumors of the thymus. An analysis of 107 cases. Cancer 15:1224-1260, 1962

12.

12. Masuda M , Arai Y , Okamura T , Mizoguchi H . Pure red cell aplasia with thymoma: Evidence of T-cell clonal disorder. Am J Haematol 54:324-328, 1997

13.

13. Mizobuchi S , Yamashiro T , Nonami Y , Yamamoto A , Kunie M , Nakaya H , Sawada T , Taguchi H , Moriki T , Ogoshi S . Pure red cell aplasia and myasthenia gravis with thymoma: A case report and review of the literature. Jpn J Clin Oncol 28:696-701, 1998

14.

14. Barnes RDS , O'Gorman P . Two cases of aplastic anemia associated with tumours of the thymus. J Clin Pathol 15:264-268, 1962

15.

15. McManus KG , Allen MS , Trastek VF , Deschamps C , Crotty TB , Pairolero PC . Lipothymoma with red cell aplasia, and lichen planus. Ann Thorac Surg 58:1534-1536, 1994

16.

16. Mamiya S , Itoh T , Miura AB . Acquired pure red cell aplasia in Japan. Eur J Haematol 59:199-205, 1997

17.

17. Kirchner T , Miller-Hermelink HK . New approaches to the diagnosis of thymic epithelial tumors. Prog Surg Pathol 10:167-189, 1989