Two cases of thymic
carcinoid tumor were reported. Case 1 was 64-year-old male who was admitted to our hospital with a complaint of
dyspnea. He was proved to have a huge anterior mediastinal
tumor by chest X-ray and chest CT. After
radiation therapy, the
tumor was resected on February 5, 1981. Pericardium was partially resected and showed
tumor invasion. Sixty-four days after operation, he died due to
respiratory insufficiency. Case 2 was 71-year-old male who was pointed out to have an abnormal shadow by X-ray mass screening and was admitted to our hospital. Chest X-ray and chest CT revealed the presence of an anterior mediastinal
tumor. Resection of the
tumor was done on February 13, 1986. Although the
tumor showed mediastinal
lymph node metastasis and invaded to the pericardium and the right lung, it was resected completely. Cytological examination of
pericardial effusion showed
tumor cells at the time of resection. He is now quite well and without any evidence of recurrence 3 year and 1 months after operation. Histopathologically, the
tumors of two cases consisted of relatively uniform cells with abundant clear or slightly eosinophilic cytoplasm and regularly and centrally located nuclei. Mitotic figures were occasionally seen in both cases. Many
tumor cells were positively to
Grimelius stain. On the other hand,
Fontana-masson stain was negative. Immunohistochemically, the
tumor cells were positively stained with anti-NSE and anti-GRP
antibodies in Case 1 and with anti-NSE antibody in Case 2.(ABSTRACT TRUNCATED AT 250 WORDS)