Management of patients with thymoma
Isobe, M.; Nishimura, Y.; Iwata, S.; Oku, H.; Horiuchi, M.; Hayashida, R.; Edakuni, S.; Takeda, Z.; Kakegawa, T.
Nihon Kyobu Geka Gakkai 36(6): 955-960
1988
ISSN/ISBN: 0369-4739 PMID: 3249066 Document Number: 325740
We reviewed 33 cases of thymoma resected in our department during the past 20 years. Prognosis's sites of direct invasion and distant metastasis were evaluated in terms of the histological type, presence or absence of myasthenia gravis, staging and treatment methods. Factors associated with a poor prognosis in this tumor included the round or oval epithelia cell type with limited lymphocytic infiltration, invasive type, in particular stage IV according to Masaoko's classification with distant metastasis, non-radical resection and no postoperative irradiation. Sites of distant metastases consisted of bone, lung, liver and lymph nodes in the msdiastinum, pulmonary hilum and supraclavicular areas. The 5 year survival rate was 70.4% and the 10-year survival rate was 63.3%. The encapsulated type showed an 84.1% 5-year survival rate, while the invasive type showed 43.6%. Causes of death in the encapsulated type included one case of recurrence of round and oval cell type, two cases of myasthenia gravis, one case of pure red cell aplasia, and one due to age. In the invasive type, apart from operative death, one stage II without postoperative irradiation, and all stage IV patients died from tumor spread, whereas all patients in stage III including those who underwent subtotal resection were still alive. Based on these results, it is suggested that total resection by combined resection of adjacent organs is indicated for the invasive type of thymoma and irradiation should be performed following subtotal resection caused by extensive tumor invasion to such organs as the aortic arch. For stage IV with distant metastasis and dissemination, more effective chemotherapy is desirable. When pathological examination shows highly malignant findings even in the encapsulated type, adjuvant therapy is required in the same manner as in the invasive type.