Chemotherapy of invasive thymoma

Outcome in excised thymomas: role of prognostic factors and impact of additional malignancies on survival

Background and aims:

Although the management of thymomas has been extensively evaluated, the value of prognostic factors in the outcome of these patients remains unclear.

Methods and results:

The medical records of all patients who underwent resection of thymoma between January 1985 and September 2010 at a single thoracic unit were reviewed. Patients were followed up with reference to disease recurrence and development of additional malignancies (AM). Total thymectomy was performed in all 68 cases. Mean follow-up time was four years. Mean survival was 63.9 months. Mean disease-free interval was 13 months. Factors affecting prognosis were Masaoka staging and WHO histological sub-type. Patients with thymomas had a higher risk of developing AM when compared with a control population of individuals with other tumours ( p = 0.0002). Among thymomas, the cortical subtype was associated with a higher risk of AM ( p = 0.047) and mortality ( p = 0.001).

Conclusions:

This data confirms that Masaoka staging and WHO histologic sub-type are the most important prognostic factors in patients with thymoma. Moreover, thymomas predominantly arising from the thymic cortex are associated with a higher risk of developing other malignancies and with poorer survival. The cortical origin of thymoma could therefore be considered as a significant prognostic factor.

Advanced Stage Thymomas and Thymic Carcinomas: Results of Multimodality Treatments

BACKGROUND

With the aim of evaluating the results of multidisciplinary approaches, we reviewed our experience in multimodality treatment of advanced stage (III and IVA) thymic tumors.

METHODS

From 1976 to 2003, 56 patients with Masaoka stage III and IVA thymic tumors underwent a multimodality treatment. Thirty-six patients underwent neoadjuvant chemotherapy, surgery, and postoperative radiotherapy; 20 patients were treated by primary surgery and postoperative radiotherapy (n = 12), chemotherapy (n = 1) or chemoradiotherapy (n = 7). The neoadjuvant or adjuvant chemotherapy consisted of three courses of cisplatin, epidoxorubicin, and etoposide every 3 weeks. Adjuvant radiotherapy consisted of 45 Gy for complete resections or 60 Gy for incomplete resections.

RESULTS

The preoperative diagnosis of invasive thymomas was performed in a total of 29 cases: 15 by mediastinotomy, 6 by video-assisted thoracoscopic surgery, and 8 by fine-needle aspiration. In 27 cases no diagnosis was available, but in most of them a thymus-related syndrome was present. Thirty-four patients are still alive (31 disease-free), and 22 have died (2 disease-free). Ten-year survival was 48% and 45.7% for stage III and IVA thymomas, respectively. The presence of myasthenia gravis (p = 0.04) and neoadjuvant chemotherapy (p = 0.004) affected survival significantly.

CONCLUSIONS

The multimodality treatment of stage III and IVA thymic tumors allows a good long-term outcome; the neoadjuvant chemotherapy improves the resectability rate and the survival of both stages of the disease.

Role of chemotherapy in the management of advanced thymic tumors

Chemotherapy has an important role in the treatment of advanced thymic tumors. Early stage tumors are successfully treated with surgery. Locally advanced tumors (Masaoka stage III and IVA) are often treated with combined modality treatment including surgery, radiation, and chemotherapy. For patients with curable thymic tumors, the ability to attain a complete resection is a critical prognostic factor. Locally advanced tumors have a relatively high risk of recurrence and decreased rates of long-term survival. A multimodality approach including induction chemotherapy and postoperative radiation therapy can improve complete resection rates and long-term outcomes. Thymic tumors are chemoresponsive with optimal responses achieved with cisplatin-based combination chemotherapy. Chemotherapy with radiation can result in long-term progression-free survival for patients with locally advanced disease who remain inoperable following induction therapy. Patients with disseminated (stage IVB) thymic tumors can also have significant disease response and palliation of symptoms when treated with chemotherapy. Octreotide and corticosteroids also have shown efficacy. For best results, it is important that thoracic surgeons, radiation oncologists, and medical oncologists work together to obtain the best local control of tumor and optimal treatment of metastases.

Thymoma and Thymic Carcinoma: Therapeutic Approaches

Thymomas and thymic carcinomas, which are rare epithelial tumors arising from the thymus gland, are the most common tumors of the anterior mediastinum. Thymomas are generally encapsulated, slow-growing tumors that have a "bland" histologic appearance. Thymic carcinomas possess more overtly malignant histologic features than thymomas and are more likely to present as invasive or disseminated disease. Surgery is the treatment of choice for localized thymic tumors, with complete resection being the most important prognostic factor. Complete resection also improves survival in locally invasive thymic tumors. Adjuvant postoperative radiation therapy may improve the outcome in patients with invasive disease, although the data are conflicting. Multimodal regimens, including neoadjuvant combination chemotherapy, surgery, and/or postoperative radiation therapy, are recommended for patients with advanced thymomas and thymic carcinomas. Use of octreotide plus prednisone has produced responses in thymomas, but the dosing and schedule have not been clearly defined. Prospective studies have been limited, and, as such, enrollment in clinical trials is encouraged.

Thymic malignancies

Thymomas and thymic carcinomas are unique tumors of the anterior mediastinum. The association of a variety of different paraneoplastic syndromes with such lesions has fascinated physicians and researchers for years. Most recently, it has been demonstrated by numerous authors that thymomas are chemosensitive tumors. Their indolent nature and relative rarity have made evaluation through prospective randomized clinical trials extremely difficult. Further information regarding the molecular nature of these neoplasms and immunologic aspects is needed in future investigation.

On the histologic heterogeneity of thymic epithelial neoplasms. Impact of sampling in subtyping and classification of thymomas

Six hundred thirty cases of thymomas were evaluated to determine morphologic heterogeneity. The thymomas were grouped in 4 categories using previous terminology. Stratification according to the number of sections available for examination revealed a marked difference in distribution by histopathologic type. A cutoff number of 5 sections appears to provide a difference in subgrouping these tumors. In addition, the proportion of invasive tumors increases with the number of sections examined. Final classification may be affected by the extent of sampling. Histopathologic classification of thymoma, although of academic interest, may have limited practical relevance for assessment of prognosis in limited biopsy tissue. Proper evaluation of histology and aggressive potential in thymoma should be based on ample sampling and assessment of capsular integrity, which is best accomplished on thoroughly sampled resection specimens rather than incomplete or limited biopsy samples.

Malignant thymoma: current status and future directions

Malignant thymomas are rare indolent tumours of the anterior superior mediastinum. Despite a benign histologic appearance, some thymomas invade nearby structures or metastasize. Patients are commonly asymptomatic, but some may present with unusual paraneoplastic syndromes such as myasthenia gravis, pure red cell aplasia, or hypogammaglobulinemia. Since tumour biopsy may potentially disrupt the thymic capsule, it is often not performed. Patients are therefore diagnosed and staged at the time of definitive surgery. Thymomas can generally be categorized into two stages: non-invasive and invasive. Prognosis closely parallels the disease stage. Surgery is the principal treatment and is curative in early stage disease. Radiation therapy, either alone or in combination with chemotherapy, is an option for both incompletely or completely resected disease. Chemotherapy is offered to patients with locally advanced, recurrent, or metastatic thymoma, with excellent responses and prolonged survival. Multicentre co-operative group clinical trials are required to assess novel thymoma therapies to maximize patient resources in this uncommon tumour.

Treatment of invasive thymoma with single-agent ifosfamide

PURPOSE

To evaluate single-agent ifosfamide in the treatment of invasive thymoma.

PATIENTS AND METHODS

Fifteen patients (eight male and seven female) with histologically confirmed invasive thymoma were treated. The median age was 48 years (range, 23 to 76 years). Four patients had stage III disease, seven patients had stage IVa disease, and four patients had stage IVb disease. The most common histologic type was lymphoepithelial. Seven patients had received prior treatment, including one patient who received chemotherapy. Ifosfamide 1.5 g/m(2) was given on days 1 to 5, with mesna as a uroprotector.

RESULTS

Thirteen patients were assessable for response. Five complete responses (38.5%; 95% confidence interval [CI], 17.7% to 64.5%) and one partial response (7.7%; 95% CI, 1.4% to 33.3%) were seen. The median duration of complete response was 66+ months (range, 25 to 87 months), and the estimated survival rate 5 years after ifosfamide treatment was 57% (SE, 32% to 79%). The most frequent toxicities were nausea, vomiting, and leucopenia, but these were well tolerated.

CONCLUSION

Single-agent ifosfamide possesses significant activity against invasive thymoma and is comparable to currently used combination regimens. The inclusion of ifosfamide in combination therapy, particularly in place of cyclophosphamide in regimens such as cisplatin, doxorubicin, and cyclophosphamide, needs to be evaluated.

Effective treatment of thymic carcinoma with operation and combination chemotherapy against acute monocyte leukemia: case report and review of the literature

Thymic carcinoma associated with acute monocyte leukemia (AMoL) and a history of choriocarcinoma was diagnosed in a 58-year-old female. We found no other such case in a literature search. She was first treated with DCMP therapy: daunorubicin, cytosine arabinoside, 6MP-riboside, and prednisolone against AMoL. After induction chemotherapy, complete AMoL remission was attained. Chest CT scan after chemotherapy revealed regression of the mediastinal tumor. Resection of the tumor included the left upper lobe of the lung, phrenic nerve and pericardium. Pathological diagnosis showed poorly or moderately differentiated squamous cell carcinoma. Although the patient died of pneumonia during chemotherapy for relapsed AMoL, chest X-ray and CT revealed no recurrence of the mediastinal tumor after the original operation. Judging from this case and other successful cases of chemotherapy, we feel that intensive chemotherapy may be a beneficial strategy against thymic carcinoma.

Thymoma. A retrospective study of 87 cases

BACKGROUND

The authors retrospectively analyzed 87 patients with malignant thymoma treated at M.D. Anderson Cancer Center between 1951 and 1990. The analysis examined the clinical stages, histologic types, and treatment modalities and attempted to determine if chemotherapy had an impact on survival.

METHODS

The patients were divided into three groups by their year of treatment and treatment modality. Patients treated between 1951 and 1975 were in Group I; patients treated between 1976 and 1980 were in Group II; and patients treated between 1981 and 1990 were in Group III. Most of the patients (18 [72%] in Group I; 16 [62%] in Group II; and 18 [50%] in Group III) had surgical resection alone or with radiotherapy. Patients with advanced-stage disease in Group I received single-agent chemotherapy, whereas patients with advanced-stage disease in Group II received a different, combination chemotherapy regimen, and those in Group III were treated primarily with cisplatin- and doxorubicin-based combination chemotherapy, e.g., the cyclophosphamide doxorubicin, and cisplatin with or without prednisone. The 17 patients treated with cisplatin with or without prednisone were separately evaluated for survival according to their response.

RESULTS

Twenty-eight patients (5 [20%] in Group I; 6 [23%] in Group II; and 17 [47%] in Group III) received chemotherapy alone or after surgery or radiotherapy. The cisplatin with or without prednisone regimen was used in 17 Group III patients for initial treatment or for relapse. The overall response rate among the patients receiving the cisplatin with or without prednisone regimen was 64%; 6 (35%) had a complete response, and 5 (29%) had a partial response. Thirty-one (36%) of the 87 total patients had 45 recurrent tumors; the lung (29%), pleura (22%), and mediastinum (18%) were the most common sites of recurrence, whereas bone was the most common distant metastatic site. The 5-year survival rate was 70% in patients with Stage I disease, 71% in patients with Stage II or III disease, and 46% in patients with Stage IV disease. The 10-year survival rate was 70% in patients with Stage I disease, 47% in patients with Stage II or III disease, and 21% in patients with Stage IV disease. Statistical analysis indicated a significant difference among the survival rates of patients with noninvasive Stage I, invasive Stage II plus III (P = 0.033), and Stage II plus III and IV tumors (P = 0.056), but not between patients with Stage II or III tumors. Patients with a major response to the cisplatin with or without prednisone regimen had a significant survival improvement compared to those with no response (P = 0.002, log-rank test).

CONCLUSIONS

Because thymoma is a chemosensitive tumor and frequently recurs in patients with Stage II or greater disease, chemotherapy carries a potential survival benefit and should be incorporated into the multimodality approach to prolong disease-free survival.

Chemotherapy for invasive thymoma. A 13-year experience

From 1977 to 1990, 37 patients with Stage III or IV invasive thymoma (20 men and 17 women; median age, 40 years of age) were referred for chemotherapy to the Padova Medical Oncology Department. All patients initially received the same regimen (50 mg/m2 of cisplatin and 40 mg/m2 of doxorubicin intravenously (IV) on day 1, 0.6 mg/m2 of vincristine IV on day 3, and 700 mg/m2 of cyclophosphamide IV on day 4 [ADOC]), recycling at monthly intervals. No life-threatening side effects were noted. The overall clinical response rate (complete response plus partial response) was 91.8%, with 43% complete remissions. Median duration of response and survival were 12 months (range, 2 to 96+ months) and 15 months (range, 5 to 96+ months), respectively. Seven of the 16 complete remissions were pathologically confirmed at subsequent thoracotomy. Other chemotherapy combinations and radiation therapy have been applied as second-line treatment, achieving only minimal responses. In the opinion of the authors, such chemotherapy deserves evaluation for adjuvant and neo-adjuvant treatment of invasive (and/or inoperable) thymoma due to the high complete response rate and overall response rate.

Successful treatment of metastatic thymic carcinoma with cisplatin, vinblastine, bleomycin, and etoposide chemotherapy

Thymic carcinomas are rare malignant neoplasms of the thymic epithelium that are distinguished from the malignant thymomas by the presence of cytologic atypia. Thymic carcinomas may metastasize outside of the thorax and are associated with a very poor prognosis. Complete responses of thymic carcinoma to chemotherapy alone have not been reported. A 21-year-old man with metastatic undifferentiated carcinoma of probable thymic origin is presented who achieved a pathologic complete response with cisplatin, vinblastine, and bleomycin chemotherapy. Additional consolidative chemotherapy with cisplatin and etoposide was administered. The patient remains disease-free 5 years after diagnosis. Cisplatin, vinblastine, and bleomycin chemotherapy appears to have significant activity against thymic carcinoma.

Metastasizing thymoma and myasthenia gravis. Favorable response to glucocorticoids after failed chemotherapy and radiation therapy

Myasthenia gravis (MG) occurs in up to 44% of patients with thymoma. Thirty-three percent of these neoplasms are invasive but extrathoracic disease is rare. Recently, we saw a patient with MG and recurrent, metastasizing mixed lymphoepithelial thymoma, whose disease was resistant to combination chemotherapy and radiotherapy but who responded dramatically to treatment with daily glucocorticoids. Thus, therapy with daily glucocorticoids should be considered in the treatment of invasive or metastatic thymoma associated with MG, including when conventional surgery, radiotherapy, and chemotherapy have failed.

Thymoma

A review of the evaluation, treatment, and end results for 52 patients with thymoma treated at The University of Texas M.D. Anderson Cancer Center (1950-1984) is presented. The objective of the study was to examine the influence of a number of clinical characteristics on survival, including histologic and staging classifications, associated diseases, symptom status, and treatment. Forty-nine patients (94%) underwent surgical exploration; 13 were stage I, 12 were stage II, and 24 were stage III. Complete resection was accomplished in all of the stage I and II groups and in 6 of the stage III patients. An asymptomatic history, surgical stage I disease, lymphocytic thymoma cell type, and complete resection favorably influenced prognosis. The cumulative 5-year survival rate for all patients was 40%. No patient with stage I thymoma had recurrent disease, however, there were 9 recurrences (50%) in the completely resected stage II/III patients, six of whom remained disease-free following treatment with radiotherapy, chemotherapy, or a combined approach.

Chemotherapy of invasive thymoma. A retrospective study of 22 cases

The authors report on combination chemotherapy in 22 patients (seven men, 15 women; age 20-67, median 38.5 years) with incompletely resected invasive thymoma. Twelve of 22 patients have had prior radiotherapy of the tumor (four of 12 local failure, eight of 12 remote metastases). By subsequent chemotherapy five of 12 obtained complete remission (CR). One of them died by relapsed tumor, another by an intercurrent infection. At 5 years after diagnosis the survival rate of the 12/22 patients was 33% (Kaplan-Meier). Ten of 22 patients received chemotherapy as primary treatment of incompletely resected thymoma. Four of 10 obtained CR. One of them was lost during follow-up, the others received adjuvant irradiation of the mediastinum and are free of disease. Two of ten obtained partial remission (PR), but relapsed within 6 months after chemotherapy. At 3 years after diagnosis the survival rate of the 10/22 patients was 34%. Thirteen of 22 patients received cyclophosphamide, doxorubicin, vincristine, and prednisone (CHOP) or CHOP/bleomycin as first chemotherapeutic regimen. Five of them achieved CR. Cyclophosphamide, vincristine, and prednisone (COP) or COP plus procarbazine (COPP) was administered to six of 22. Three of them obtained a CR and one a PR. In an alternating manner COPP and Einhorn regimens were given to two of 22, one of which had a CR. In one of 22 the doxorubicin, bleomycin, cisplatin, prednisone (BAPP) regimen was followed by a PR. The authors conclude that combination chemotherapy is effective in the first-line postsurgical treatment of incompletely resected thymoma and also in the treatment of local or metastatic relapses after radiotherapy.

Combination chemotherapy with cyclophosphamide, adriamycin, and vincristine in malignant thymoma and myasthenia gravis

Malignant thymoma (MT) is a rare tumor that is often associated with myasthenia gravis (MG). This tumor is considered resistant to chemotherapy. We had the opportunity to treat five patients with MT with cyclophosphamide 800 mg/m2, Adriamycin 50 mg/m2, and vincristine 1.4 mg/m2 (CAV) in cycles of 21 days. Two patients with MG that was resistant to antimyasthenic drugs immediately responded to this combination. One patient with only MT had a complete response, and two patients with only MT had a partial response. Two out of the five patients are still alive and free of disease. Two patients died of disease, and one died from a neutropenia-induced respiratory tract infection. It is concluded that this combination chemotherapy is active in MT and MG and deserves additional trials.

Thymoma presenting as a superior vena cava syndrome remission following therapy

A 45-year-old male developed myasthenia gravis 8 years ago. He received prednisone for 3 years, and resumed complete clinical remission. Five years later, he was admitted with obstruction of the superior vena cava. Invasive thymoma was diagnosed by chest X-ray and an open lung biopsy. Radiation followed by combination chemotherapy with cyclophosphamide, vincristine, and prednisone induced a complete remission. The patient remained disease-free for more than 20 months after the first admission to our department. To the best of our knowledge, superior vena cava syndrome as the presenting symptom of thymoma has never been reported previously.

Hepatic metastatic thymoma and myasthenia gravis twenty-two years after the apparent cure of an invasive thymoma. A case report and review of the literature

We report the case of a 62-year-old woman who presented in myasthenic crisis 22 years after radiation- and chemotherapy of an invasive thymoma which occurred during pregnancy. There was no evidence of recurrence of the thymoma at its original site, but an isolated hepatic metastasis was discovered. Biopsy of the mass revealed a spindle cell thymoma, whereas the original histology was that of a mixed round and spindle cell thymoma with moderate lymphocytic infiltration. The patient expired in spite of treatment with steroids, pyridostigmine bromide and plasma exchange on the one hand and cyclophosphamide with adriamycin on the other. To our knowledge, 22 years is the longest reported interval for the appearance of metastatic thymoma and myasthenia gravis after the diagnosis and apparent cure of a primary thymoma. This is also the only reported case of thymoma occurring during pregnancy but not associated with a rapidly fatal outcome.

Chemotherapy in invasive thymomas: five case reports

We treated 5 cases of invasive thymomas with single agent and combination chemotherapy. A carcinoid tumor of the thymus had a 13-month objective response to monthly courses of a combination of DTIC, adriamycin, cytoxan, and vincristine. A second case of carcinoid achieved stabilization of disease with a combination of adriamycin, cyclophosphamide, and DTIC for 9 months and subsequently 10 months, with fluorouracil and methotrexate. A case of thymoma had stabilization of disease for 14 months with oral cytoxan and prednisone.

Chemotherapy of malignant thymoma. Case report and review of the literature

The authors report the case of a patient with malignant thymoma unresponsive to combination chemotherapy (cyclophosphamide, doxorubicin, vincristine, and prednisone [CHOP] and cisplatin/VP-16) who subsequently achieved clinical response to continuous daily prednisone. A review of the literature indicates that prednisone and cisplatin are the most active agents in the treatment of malignant thymoma.

Remission of invasive thymoma due to chemotherapy. Two patients treated with cyclophosphamide, doxorubicin, and vincristine

Information regarding the effectiveness of chemotherapy in cases of invasive thymoma is limited. Two patients in whom the combination of cyclophosphamide, doxorubicin, and vincristine produced remission of invasive thymoma are described. The durations of remission were eight and seven months, respectively. In both patients, recurrence was observed at the site of bulky disease, and a secondary complete response continuing for 37 months was achieved in one of them with radiation therapy.

Invasive carcinoma of the thymus. A multicenter retrospective review of 56 cases

This multicenter retrospective study included 56 cases of histologically reviewed invasive epithelial thymic tumors. All these patients underwent surgical treatment or exploration and were referred for complementary radiotherapy. The majority received a dose higher than 4000 rad. Twenty-three out of 50 patients (46%) with incomplete resection received some chemotherapy. The local recurrence rate at 2 yr was 34%. The overall 5-yr actuarial survival was 46%. There was no evidence of any relationship between radiation dose and local control. No difference in survival was observed with or without chemotherapy, nor according to histological type or lymphocytic infiltration, except cases with very undifferentiated carcinomas which presented a worse prognosis. Nor was any difference in survival observed between patients benefiting from incomplete resection and those only having undergone exploratory thoracotomy and biopsy. Radiotherapy seems to decrease the rate of local recurrence in invasive carcinoma of the thymus. The role of chemotherapy is still debatable, but it could have a role in decreasing tumor volume before radiotherapy. This study has shown the necessity of histological review by a panel of histopathologists in an attempt to better define terminology and diagnosis. A prospective study is necessary in order to solve the problems of concepts and management in epithelial thymic tumors.

Carcinoid tumor of the thymus

Primary carcinoid tumor of the thymus is a rare, slow-growing neoplasm occurring most commonly in middle-aged men. The usual clinical manifestations are those of a mediastinal mass, although in asymptomatic patients, the diagnosis may be suggested by a routine chest roentgenogram. Excision is the most common treatment. Because the disease may recur up to ten years after surgery, follow-up is important. The case reported here is of a 49-year-old man who was hospitalized for evaluation of a mediastinal mass first detected six years previously. When laboratory and other tests proved nondiagnostic, thoracotomy was done and pathologic examination of the excised mass revealed carcinoid tumor of the thymus.

Malignant thymoma associated with liposarcoma of the mediastinum--a case report

Malignant thymoma occurring concurrently with mediastinal liposarcoma in a 49-year-old man is described. The patient underwent an incomplete resection of the mediastinal mass followed by irradiation therapy and additional chemotherapy. He died about 9 months after the detection of a mediastinal mass on chest X-ray films and the immediate cause of death was superior vena cava syndrome. The incidence of primary liposarcoma of the mediastinum alone is extremely rare. Only a few more than 20 with such a lesion have been documented in Japan. A review of the literature of patients with mediastinal liposarcoma and thymoma associated with malignancies revealed no case of an association of thymoma and liposarcoma.

T-cell chronic lymphocytic leukemia in a patient with invasive thymoma in remission with chemotherapy

This is a case report of a patient with invasive thymoma. Subsequently to radiotherapy and steroids, a combination chemotherapy of cis-platinum (CDDP) and doxorubicin was tested with good results. The patient later developed a chronic lymphocytic leukemia (CLL); morphologically and cytochemically a T-CLL with skin localizations, hepatomegaly, and a high leukocyte count.

Metastatic thymoma with myasthenia gravis: complete remission with combination chemotherapy

A 29-year-old male developed myasthenia gravis 29 months after resection of a "benign" mediastinal thymoma. Metastatic thymoma was found in the pleura 45 months after the initial surgical resection. Combination chemotherapy with cyclophosphamide and doxorubicin produced a complete remission of the metastatic thymoma which has continued for 13 months. Concurrently, there has been a marked increase in neuromuscular function.

Treatment and prognosis of thymoma: a review of 25 cases

Experience of 25 patients with thymoma is reported. Based on the presence or absence of gross invasion 17 tumors were regarded as benign, 8 as malignant. All patients were operated on. Twenty-two had a complete excision, 2 a palliative excision, and 1 a biopsy only. Five patients received post-operative radiotherapy and 2 patients were given cytotoxic chemotherapy. None of the 17 patients with a benign thymoma had a recurrence or death due to thymoma during the follow-up. The five- and ten-year survival rates for malignant thymoma were 50% and 17%, respectively. Excision is the treatment of choice for all thymomas, since the prognosis for benign tumor is excellent and the malignancy can only by determined at exploration. Post-operative radiotherapy seems to be indicated in malignant thymoma. Myasthenia gravis and histologic features of thymoma have some value in predicting prognosis.

Long-lasting response to cis-platinum in recurrent malignant thymoma: case report

A patient who had received irradiation for inoperable invasive thymoma was treated with cis-platinum after mediastinal and endothoracic recurrence two years from diagnosis. A quick and long-lasting response was observed, which is still present. Systematic phase II trials with cis-platinum in invasive thymoma are suggested.

A complete response in metastatic malignant thymoma to cis-platinum, doxorubicin and cyclophosphamide: a case report

Systemic chemotherapy as a mode of therapy in metastatic malignant thymoma has never been systematically evaluated. Chemotherapeutic agents, including doxorubicin, cyclophosphamide, cis-platinum, nitrogen mustard, prednisone or combination of agents like MOPP have produced tumor remission. A case report of complete remission of malignant thymoma in which the combination of cyclophosphamide, doxorubicin and cis-platinum (CAP) was used is reported.

Malignant, predominantly lymphocytic thymoma with central and peripheral nervous system metastases

Histologic features of an invasive mediastinal tumor found in a 25-year-old woman fulfilled the accepted criteria for diagnosis of predominantly lymphocytic thymoma. Histochemical and cell marker studies indicated that the neoplasm contained a preponderance of T lymphocytes. After surgical debulking of the mass, aggressive radiotherapy and chemotherapy eradicated all evidence of thoracic disease. However, six months after the initial diagnosis, rapid development of cranial nerve and brainstem metastases--without detectable recurrent disease elsewhere--resulted in the patient's death. Autopsy examination revealed the presence of peripheral nerve metastases as well. A review of the literature disclosed fewer than 10 cases of central nervous system metastasis from thymoma. In only two of these were there clinicopathologic features similar to those seen in this case.

Treatment of invasive or metastatic thymoma: report of eleven cases

The clinical presentation and therapeutic modalities of 11 patients with invasive or metastatic thymoma are presented. Two patients had myasthenia gravis, and five had extrathoracic metastases. Survival exceeded five years in five patients, and four patients remain free of recurrence between 2.1 and 9.0 years after diagnosis. Surgery, with an attempt at complete resection, is the first step of therapy. A second thoracotomy for local relapse or attempt at curative resection was carried out in four patients. Radiotherapy to the mediastinum and/or metastatic sites was given to ten patients with doses ranging from 3600-6000 rads (median = 4500 rads) in the nine nonmyasthenic patients. Inclusion of supraclavicular fossae in the radiotherapy field is recommended because it was a site of relapse in two patients. Systemic therapies were given to eight patients. Objective responses were seen with two of various chemotherapeutic regimens. A combination of bleomycin, Adriamycin, cisplatin, and prednisone ("BAPP") produced a partial remission in two of five patients, during 12 and 4 months, respectively. Two of three patients responded to maytansine as a single agent after failure of other agents. Immunotherapy with intravenous Corynebacterium parvum or intradermal Methanol-Extraction Residue of bacillus Calmette-Guérin (MER-BCG) was ineffective in one patient each. The importance of combined modalities in the management of the disease is emphasized.

Combination chemotherapy in invasive thymoma role of COPP

Combination chemotherapy consisting of cyclophosphamide, vincristine, prednisone, and procarbazine (COPP) was administered to 5 patients with invasive lymphoepithelial thymoma. Objective evidence of tumor regression was seen in 4 patients. Given prior to preoperative radiation therapy, COPP produced partial remissions in 2 patients, making possible smaller radiation treatment fields. Two patients with pleural involvement when first seen, achieved tumor regression when COPP was given prior to radical radiation therapy. One of these patients remains disease-free at 34 months; the other succumbed to pneumonitis. One patient, presenting with pleural metastasis three years after undergoing incomplete resection of thymoma, failed to respond to treatment. Combination chemotherapy with COPP can produce objective regression of invasive lymphoepithelial thymomas which may be useful in the preoperative management of selected cases, as well as in the management of unresectable or metastatic disease.

[A comparative clinical and pathological study on the classification and prognostic features of 57 thymomas. II. prognostic features (author's transl)]

The most important prognostic determinants of the thymomas are the gross findings at operation (equal to the presence or absence of gross invasion of adjacent tissue) and the presence or absence of the thymoma-associated systemic disease, particulary myasthenia gravis. The histologic type of thymoma had no proof value in predicting prognosis with the exception of the so-called atypical thymomas. Thirty-four of 57 patients with thymomas were females and 23 males. The tumors in 40 cases were non-invasive thymomas, and in 17 cases the tumour were invasive of adjacent tissue. 35.1 percent of patients were asymptomatic, the tumours being discovered on roentgenograms done on a routine basis or for an unrelated porpose. 40.3 percent of patients have had a thymoma-associated systemic disease. The most common presenting symptoms were related to myasthenia gravis (26.3%). The 5-year survival rate was 90 percent for non-invasive thymomas without myastenia gravis and 50 percent for invasive thymomas. The 5-year survival rate for patients with myasthenia gravis and encapsulated (non-invasive) thymomas was approximately 60 percent, whereas that for invasive thymomas with myasthenia gravis was 40 percent. The primary form of therapy for all thymomas is the surgical excision. In cases with invasive and/or metastasizing thymomas, postoperative radiation and adjuvanted chemotherapy is indicated, but in most series, the longterm results of this form of therapy are discouraging.

"Disappearing" spinal cord compression: oncolytic effect of glucocorticoids (and other chemotherapeutic agents) on epidural metastases

Four patients suffering spinal cord compression resulting from epidural metastases were treated with adrenocorticosteroid hormones. For 2 patients, prompt relief of symptoms followed glucocorticoid therapy alone and was associated with marked shrinkage or disappearance of the metastasis, a direct oncolytic effect of the steroids. For the other 2 patients, glucocorticoids combined with other chemotherapeutic agents caused disappearance of the extradural tumor. For 1 patient, failure to recognize the oncolytic effects of the chemotherapy led to an unnecessary surgical procedure, and for a second patient an unnecessary operation was narrowly averted. Thus, for certain patients, glucocorticoids may occasionally have a marked oncolytic effect on epidural metastatic tumors.