Abstract The thymus, said to be the “organ of mystery” throughout the 2000-year history of medicine, demonstrates a variety of clinical and pathologic manifestations that require comprehensive understanding of its entity. In this study, we discuss the profile of patients with thymic epithelial tumors seen in the Philippine Heart Center, including the variable clinical, pathologic, immunohistochemical and prognostic features. For the last 30 years, surgically resected cases of thymic epithelial tumors were reviewed. We used descriptive statistics and quanititative variables are expressed as mean, range and standard deviation whereas qualitative variables are expressed as proportion. A comprehensive review of the tumor registry in our center revealed majority of mediastinal masses, 75% occured at the anterior compartment, 4% in the posterior compartment and 1% from the superior compartment. Thymomas are most common among the adult age group with an average mean age of 42 years. Other thymic tumors encountered were thymic carcinoma, lymphoma, cysts, and carcinoid. In recent years, several variants of thymic epithelial tumors have been observed, some with unique biological behavior, high malignant potential, frequent metastases, and tumor recurrence. Such cases as primary neuroendocrine carcinoma with oncocytic differentiation, composite Hodgkins and Non-Hodgkins lymphoma arising from the thymus and thymic carcinoma arising from a thymoma has definitely challenged the Pathologist. In such cases, several battery of immunohistochemical studies were done, such as Cytokeratin 7 and 20, Chromogranin, Synaptophysin, Neuron Specific Enolase, CD 3, CD 15, CD 20, CD 30, CD 68, and LCA. The series of neoplasm presented varies in clinical and histopathologic presentation. Its histologic variants and spectrum of differentiation are necessary to be defined, the soonest possible time. This will eventually lead the pathway towards treatment options. The World Health Organization histologic classification for thymic tumors paved the way to a better phase in the prognostication of thymic epithelial tumors. A greater challenge for the Pathologist is to prove the existence of synchronous, concurrent and composite tumors in the thymus. Most of these tumors are far advanced upon diagnosis, and therefore requires more aggressive treatment. Citation Information: Cancer Prev Res 2010;3(1 Suppl):A136.
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