Malignant thymoma

Abstract

Sixty‐one patients underwent operations for malignant thymomas between 1961 and 1989. Twenty‐three patients had associated myasthenia gravis (MG), an incidence of 37.7%. Upon being admitted to the hospital, the patients' most common symptoms included chest pain, MG, cough, and dyspnea. Only 7 of 61 (11.5%) patients had no symptom. Tumor staging of 58 patients with invasive thymomas was performed according to Masaoka classification. The patients were classified as follows: Stage 11 disease, 5; Stage 111, 41; Stage IVa, 8; and Stage IVb, 4. In addition, thymic carcinoma was present in three patients. The series had a resection rate of 55.7%. The incidence of operative complications was 16.3%. Only one patient died of myocardial infarction; the incidence of operative mortality was 1.6%. The patients with MG had a higher rate of resection (69.6%) and a higher incidence of complete thymectomy (14 of 23 patients; 60.9%). Mixed lymphoepithelial tumors and epithelial cell predominant tumors were the most frequent histologic patterns (45.9% and 34.4%, respectively). Fifty‐two patients had postoperative radiation therapy, and 10 patients had chemotherapy. The overall cumulative survival rates in the series were 59% and 34% at 5 and 10 years, respectively. The results demonstrated that the factors affecting the prognosis may include resectability, postoperative irradiation or chemotherapy, MG, and tumor staging. The influence of histologic variation on survival rates could not be clearly defined in the series. Surgical resection, particularly complete thymectomy, followed by irradiation is the primary option of therapeutic management for malignant thymoma. Cancer 1992; 70:443–450.

WHO types A and AB thymomas: not always benign

“…Although some promote and anticipate a benign clinical course for these tumors, 6,[12][13][14][15][16] others (ourselves included) consider all thymomas as potentially malignant neoplasms. [1][2]10,[17][18][19][20][21][22][23][24][25][26][27][28][29][30][31][32][33][34] Many prior studies have documented malignant behavior in types A and AB thymomas. In our retrospective study of 71 cases of types A and AB thymomas (37 cases with follow-up information available), 18 patients (nine each of types A and AB) developed recurrence and or metastases.…”

Thymoma and thymic carcinoma

“…12 Advances in MG medical management made surgery less risky and contributed to an improved postoperative recovery and outcome. As a consequence, most of the recent reports have supported either a trend 8,29 or signifi cantly better survival 7,9,30,49,50 in MG patients. This is probably related to the fact that the MG workup favors early diagnosis of thymoma; in fact, most of the MG patients included in these studies had predominantly stage I and II tumors.…”

“…50 However, there are few objective data substantiating this assumption. The occasional occurrence of multiple thymoma has been reported in other studies.…”

Thymoma: Update for the New Millenium

“…Operation for thymoma carries a low morbidity 240 Thymoma: Update for the New Millenium and mortality, and should be considered the mainstay of treatment in patients with resectable disease [20]. Although operative mortality is low, most surgical deaths can be attributed to MG crisis [6].…”