A multidisciplinary approach to therapy for unresectable malignant thymoma

Induction Strategy for Locally Advanced Thymoma

Surgery remains cornerstone for the management of thymoma. Complete surgical resection (R0), is recognized as the constant and significant factor for prognosis. However, in locally advanced (Masaoka-Koga stages III-IVa) thymomas, achieving R0 resection remains challenging due to local-regional invasion of the disease. Induction treatment, with the aim of reducing bulky tumor mass, offers new strategy to facilitate totally surgical resection. Herein, we reviewed recent progress and provided a comprehensive overview of induction strategy in locally advance thymoma.

Evaluating the effectiveness of chemotherapy for thymic epithelial tumors using the CD-DST method

BACKGROUND

Thymic epithelial tumors (TET) are frequently eligible for curative-intent surgical resection. For locally advanced TETs, chemotherapy has been used to both reduce the tumor burden and achieve prolonged disease control. However, effective therapy for this disease largely remains to be determined. Here, we report the chemosensitivity of 100 patients with TETs determined by the collagen gel droplet embedded culture-drug sensitivity test (CD-DST).

METHODS

A total of 100 patients with TETs underwent surgical resection. The efficacy of antitumor agents on TET cells was tested by CD-DST.

RESULTS

Thymic epithelial tumors were pathologically confirmed after surgery: two cases were type A thymoma, 17 were type AB, 12 were type B1, 44 were type B2, 12 were type B3, and there were 13 cases with thymic carcinoma. A total of 36% patients with TETs were sensitive to different types of chemotherapeutic agents. There was no significant differences in age, histological type, clinical staging, or association with autoimmune diseases between sensitive and nonsensitive cases. Type B1 and B2 thymoma were relatively more sensitive to chemotherapeutic agents (6/12 and 18/44, respectively), while sensitivity of type B3 cases to chemotherapeutic agents was much lower (only 2/12). Cases with type A thymoma were not sensitive to any antitumor drugs. Among 11 chemotherapeutic agents tested in our study, the sensitivity of TETs to EPI was the highest (16%). No patients with thymoma were sensitive to Alimta (Pemetrexed).

CONCLUSIONS

Our work illuminates the effectiveness of chemotherapy for TETs and provides important clues for choosing antitumor drugs with relatively high drug sensitivity to TETs in advance.

Intensity Modulated Radiation Therapy Plus Etoposide/Cisplatin for Patients With Limited Advanced Unresectable Thymic Epithelial Tumors: A Prospective Phase 2 Study

PURPOSE

This prospective phase 2 study evaluated the efficacy and safety of intensity modulated radiation therapy plus etoposide/cisplatin (EP) for patients with unresectable thymic epithelial tumors (TETs).

METHODS AND MATERIALS

Patients with limited advanced unresectable TETs whose lesions could be encompassed within radiation fields were enrolled in this study. Two cycles of EP (75 mg/m² etoposide and 25 mg/m² cisplatin on days 1-3 and days 29-31) were administered concurrently with radiation therapy, followed by 2 cycles after radiation therapy. The primary endpoint was the objective response rate. The secondary endpoints were the progression-free survival rate, overall survival rate, and incidence of adverse events.

RESULTS

Fifty-six patients were enrolled between June 2011 and May 2018. Twenty-two and 34 patients had thymomas and thymic carcinomas, respectively. The median age was 52 (range, 21-76) years, and 30 patients (53.6%) were men. Eight patients (14.3%) had stage III tumors, 6 (10.7%) had stage IVA tumors, and 42 (75.0%) had stage IVB tumors. The objective response rate was 85.7% (95% confidence interval, 76.3%-95.2%). With a median follow-up of 46 (range, 7-101) months, the 1-, 2-, and 5-year progression-free survival rates were 66.1%, 48.0%, and 29.5%, and the 1-, 2-, and 5-year overall survival rates were 91.0%, 76.2%, and 56.2%, respectively. The most common grade 3 to 4 adverse event was leukopenia (42.9%). Pulmonary fibrosis was also observed (5.3%).

CONCLUSIONS

Because intensity modulated radiation therapy with EP is effective and safe for limited advanced unresectable TETs, it could be a suitable treatment option for such patients.

Efficacy and toxicities of gemcitabine and cisplatin combined with endostar in advanced thymoma and thymic carcinoma

BACKGROUND

Thymoma and thymic carcinoma are rare thymic epithelial tumors. We investigated the efficacy of first-line gemcitabine and cisplatin (GP) chemotherapy versus gemcitabine and cisplatin chemotherapy combined with the anti-angiogenic drug endostar (GP + E) in advanced thymoma and thymic carcinoma.

METHODS

The records of 45 patients with invasive metastatic thymomas or thymic carcinomas treated with GP as first-line therapy between August 2008 and July 2017 at the Department of Respiratory Medicine, Peking University Cancer Hospital and Institute were retrospectively reviewed.

RESULTS

Eighteen patients (75%) in the GP + E group achieved a partial response and six (25%) had stable disease. In GP only group, nine (42.8%) patients achieved a partial response, 11 (52.4%) had stable disease, and one (4.8%) had progressive disease. The GP + E group had a significantly higher overall response rate (75% vs. 42.9%; P = 0.028), and median progression-free survival (PFS) and overall survival (OS) of 19 and 76 months, respectively. In the GP only group, median PFS and OS were 16 and 29 months, respectively. PFS and OS were not significantly different between the groups.

CONCLUSIONS

GP has moderate efficacy and could represent a suitable first-line therapy for thymic carcinoma and thymoma. Chemotherapy combined with endostar could improve the overall response rate, but did not prolong PFS or OS.

The Place and the Role of Radiation Therapy in the Treatment of Thymic Carcinoma

Thymic carcinomas arise from the epithelial cells of the thymus gland and are the most common tumors of the anterior mediastinum despite their overall rarity. Because of their rarity, their treatment remains a challenging topic. Although historically they have been treated surgically, radiation therapy (RT) has an important role either as a definitive or as a postoperative treatment. In this article, we present a review of the current therapies for the thymic carcinomas and try to identify the exact place of the RT in the optimal management of these patients.

The clinical features, diagnosis and management of recurrent thymoma

Thymoma is a disease with malignant potential, which has a recurrence rate after complete resection ranging from 5 to 50 %. Multiple studies on the risk factors, treatment or prognosis have been reported. Many of them are controversial, however. In this review, we summarized some accepted risk factors, means of diagnosis and different treatments of recurrent thymoma. The risk factors of recurrent thymoma haven’t been well-studied, and its management remains controversial. We reviewed the literatures and found some key points which should be noticed during the surgery of initial thymoma. Although reoperation should be taken into account preferentially, multimodal treatments are also available. The prognosis are also been discussed.

Treatment Modalities and Outcomes in Patients With Advanced Invasive Thymoma or Thymic Carcinoma: A Retrospective Multicenter Study

INTRODUCTION

We investigated the relationships between treatment characteristics and long-term outcomes in patients with locally advanced thymoma or thymic carcinoma.

METHODS

We retrospectively reviewed 146 patients treated from 1980 to 2011 at 2 tertiary cancer care centers, 110 with Masaoka-Koga stages III to IVA invasive thymoma and 36 with stages I to IVA thymic carcinoma. Survival probabilities were estimated using the Kaplan-Meier method. Risk factors related to survival were identified by univariate and multivariate competing risk analysis, with overall survival (OS) as the competing risk. The Cox regression analysis was used to identify risk factors for OS.

RESULTS

Median follow-up time for all patients was 64 months. At 5 and 10 years, rates of OS and freedom from recurrence (FFR) were 81% and 58% and 81% and 65%, respectively. Of the patients who underwent surgery, trimodality treatment produced better survival compared with less aggressive treatment among patients with stage III disease (P=0.03). Among patients who underwent trimodality treatment, patients with stage III disease had better OS (P=0.03) and FFR (P<0.001) than those with stage IVA disease. On Cox regression analysis, decreased OS was associated with thymic carcinoma (hazard ratio [HR], 7.36; 95% confidence interval [CI], 2.38-22.77; P=0.001), R2/unresectable disease (HR, 8.45; 95% CI, 1.44-49.42; P=0.02), and an Eastern Cooperative Oncology Group performance score of 1 (HR, 8.14; 95% CI, 1.55-42.75; P=0.01) or 2 to 3 (HR, 29.60; 95% CI, 4.0-218.98; P=0.001) versus 0.

CONCLUSIONS

Aggressive treatment with chemotherapy, surgical resection, and postoperative radiation therapy can produce long-term survival for patients with invasive thymic malignancies.

Pretreatment biopsy for histological diagnosis and induction therapy in thymic tumors

BACKGROUND

This study was to investigate the value of pretreatment biopsy for histological diagnosis and induction therapies in the management of locally advanced thymic malignancies.

METHODS

The clinical pathological data of patients with thymic tumors in the Chinese Alliance for Research in Thymomas (ChART) who underwent biopsy before treatment from 1994 to December 2012 were retrospectively reviewed. The application trend of preoperative histological diagnosis and its influence on treatment outcome were analyzed.

RESULTS

Of 1,902 cases of thymic tumors, 336 (17.1%) had undergone biopsy for histological diagnosis before therapeutic decision was decided. In recent years, percentage of pretreatment histological diagnosis significantly increased in the later ten years than the former during the study period (P=0.008). There was also a significant increase in thoracoscopy/mediastinoscopy/E-BUS biopsy as compared to open biopsy (P=0.029). Survival in Patients with preoperative biopsy for histology had significantly higher stage lesions (P=0.000) and higher grade malignancy (P=0.000), thus a significantly lower complete resection rate (P=0.000) and therefore a significantly worse survival than those without preoperative biopsy (P=0.000). In the biopsied 336 patients, those who received upfront surgery had significantly better survival than those received surgery after induction therapy (P=0.000). In stage III and IVa diseases, the R0 resection rate after induction therapies increased significantly as compared to the surgery upfront cases (65.5% vs. 46.2%, P=0.025). Tumors downstaged after induction had similar outcomes as those having upfront surgery (92.3% vs. 84.2%, P=0.51). However, tumors not downstaged by induction had significantly worse prognosis than those downstaged (P=0.004), and fared even worse than those having definitive chemoradiation without surgery (37.2% vs. 62.4%, P=0.216).

CONCLUSIONS

It is crucial to get histological diagnosis for thymoma before surgery or adjuvant treatment and minimally invasive biopsy should be undertaken. Although in our study we could not find the benefit of induction chemotherapy before surgery in survival and recurrence rate, it could increase the R0 resection rate compared with direct surgery in late stage (III and IVa).

Available evidence and new biological perspectives on medical treatment of advanced thymic epithelial tumors

Thymic epithelial tumors (TETs) are rare primary mediastinal tumors arising from thymic epithelium. Their rarity and complexity hinder investigations of their causes and therapy development. Here, we summarize the existing knowledge regarding medical treatment of these tumors, and thoroughly review the known genetic aberrations associated with TETs and the present status of potential biological treatments. Epidermal growth factor receptor (EGFR), stem-cell factor receptor, insulin-like growth factor-1 receptor (IGF1R), and vascular endothelial growth factors (VEGF-A, VEGF-B, and VEGF-2) are overexpressed in TETs. EGFR overexpression in TETs is associated with higher stage, and IGF1R overexpression has poor prognostic value. Data indicate that anti-IGF1R monoclonal antibodies, and inhibitors of angiogenesis, somatostatin receptors, histone deacetylase, mammalian target of rapamycin, and cyclin-dependent kinases may be active against TETs. Continued investigations in this field could lead to advancement of targeted and biological therapies for TETs.

Therapy for thymic epithelial tumors

Thymoma is the most common tumor of the anterior mediastinum. This tumor is associated with unique paraneoplastic syndromes. The rarity of this tumor has somewhat obscured the optimal treatment for this disease. The World Health Organization classification system, which published in 1999, appears to be an advance in our understanding of thymoma. The Masaoka classification is now the most widely accepted and is an excellent predictor of the prognosis of thymoma. Now the International Thymic Malignancy Interest Group is currently engaged in the development of a validated formal TNM classification system for thymic malignancies. The optimal treatment of thymoma is performed according to its clinical stage. Surgery remains the mainstay of treatment for thymic epithelial tumors. Minimally invasive surgery including thoracoscopic surgery and robotic surgery for stage I and II thymomas is increasing now. The value of postoperative radiotherapy in completely resected stage II or III tumors is questionable. As thymomas have a moderate response rate to chemotherapy or radiotherapy, multimodality therapy involving surgery, chemotherapy and radiotherapy appears to increase the rate of complete resection and survival in the advanced (stage III and IV) thymomas.

Radiotherapy for thymic carcinoma: adjuvant, inductive, and definitive

Although historically thymoma and thymic carcinoma have been treated surgically, radiation therapy also has an important role, either as postoperative therapy to reduce the risk of mediastinal recurrence or as part of definitive treatment for patients who cannot undergo surgery. Induction chemotherapy and molecular targeted agents may also be appropriate for thymic carcinoma, the behavior of which resembles non-small-cell lung carcinoma more than that of thymoma or invasive thymoma and is increasingly being treated like lung cancer. We present here a review of current therapies for thymic malignancies and briefly discuss the potential benefits from novel technologies for such treatment.

Thymic neoplasms: an update on the use of chemotherapy and new targeted therapies. A literature review

Thymic malignancies represent a wide range of clinical, histological and molecular entities, with probably considerable heterogeneity even among tumors of the same histotype. Systemic chemotherapy with cisplatin-based regimens continues to represent the standard of care in metastatic or inoperable refractory/recurrent diseases and ADOC regimen (including cisplatin, doxorubicin, vincristine and cyclophosphamide) demonstrated the longer overall response rate and median survival in the first line setting, although no randomized trial is available; and there is still a lack of standard treatment after first-line failure. To date research efforts are focused on translational studies on molecular pathways involved in thymic tumors carcinogenesis, aimed to better understand and predict the efficacy of chemotherapy and targeted therapy. Recent molecular characterization includes identification of a number of oncogenes, tumor suppressor genes, chromosomal aberrations, angiogenic factors, and tumor invasion factors involved in cellular survival and proliferation and in tumor growth. The use of biologic drugs is currently not recommended in a routine practice because there are limited data on their therapeutic role in thymic epitelial tumors. Because of the lack of data from adequate-sized, prospective trials are required for validation and the enrolment of patients with advanced disease into available clinical trials has to be encouraged.

Chemotherapy for thymic carcinoma and advanced thymoma in adults

BACKGROUND

Thymic carcinoma or advanced thymoma is a rare cancer of the thymus gland that tends to be aggressive and infiltrate neighbouring organs, making total resection very difficult. Induction or adjuvant chemotherapy, or both, are often used in a multimodality approach to treat people affected by this condition, but the effectiveness of chemotherapy for thymic carcinoma or advanced thymoma remains uncertain.

OBJECTIVES

To assess the role of chemotherapy in adults with thymic carcinoma or advanced thymoma.

SEARCH METHODS

We searched the Cochrane Central Register of Controlled Trials (CENTRAL 2012, Issue 7), MEDLINE (accessed via Ovid from 1966 to July 2012), EMBASE (accessed via Ovid, from 1980 to July 2012), Latin American and Caribbean Literature on Health Sciences (LILACS), the Chinese Biological Medicine Database (CBM, 1978 to July 2012), China National Knowledge Infrastructure (CNKI, 1980 to July 2012) and the Chinese scientific periodical database VIP Information (VIP, 1989 to July 2012). There was no language restriction in searching for studies.

SELECTION CRITERIA

We planned to include randomised controlled trials (RCTs) of  trials using chemotherapy (either single-agent or combination chemotherapy plus surgery, radiotherapy or not) for thymic carcinoma and/or advanced thymoma. We planned to include all adults (aged 18 years and over) diagnosed with thymic carcinoma and/or with Masaoka stage III or IV thymic tumours. The intended primary outcomes were overall survival (OS) and progression-free survival (PFS).

DATA COLLECTION AND ANALYSIS

Two review authors independently evaluated the search results according to the inclusion and exclusion criteria. There were no studies identified for inclusion and therefore no data extraction was completed.

MAIN RESULTS

No RCTs were eligible for inclusion in this review. We report details of excluded prospective studies in an additional table and try to provide some useful evidence regarding current practice.

AUTHORS' CONCLUSIONS

There were no RCTs eligible for inclusion in this review. In current practice the most common regimen for adult patients with thymic carcinoma or advanced thymoma is cisplatin-based chemotherapy. Considering the condition is rare, it is suggested that an international group is set up to organise and evaluate prospective collection of data from cohorts of patients to inform current clinical practice.

Multidisciplinary treatment of malignant thymoma

PURPOSE OF REVIEW

Thymomas are the most common tumors of the anterior mediastinum. Although surgery remains the only curative treatment, the use of multimodality therapy for primary unresectable thymomas has led to change the clinical management of these tumors.

RECENT FINDINGS

Nowadays Masaoka stage, WHO, and radical surgical resection are considered by many authors as independent prognostic factors for long-term survival. Radiotherapy may be useful as adjuvant therapy in cases of incomplete surgical resection with microscopic or macroscopic residual disease, or for those patients with locally advanced or metastatic unresectable disease. Chemotherapy is considered a valid option in selected patients with residual disease after local treatments or as a neoadjuvant approach to improve resectability in Masaoka stages III or IV-a thymomas. Currently, no standardized regimen for chemotherapy or agreed timing exists.

SUMMARY

So far, multimodality treatment has been related to low morbidity and long survival rate, but there are still many concerns regarding a different regimen of therapy and the correct timing.

Induction therapy for thymic malignancies

Thymic malignancies are rare tumors of the chest that express a broad range of biological behaviors. Surgery remains the mainstay of therapy, and complete surgical resection is the primary predictor of long-term survival. Although there is a paucity of clinical trials assessing the role of induction/adjuvant chemotherapy and/or radiation therapy in the treatment of thymic malignancies, existing data suggest that induction therapy should be offered for the treatment of advanced-stage disease, and postoperative radiation for specific stages.

Chemotherapy for thymic tumors: induction, consolidation, palliation

Although thymoma and thymic carcinoma are rare malignancies, they constitute a large proportion of tumors of the anterior mediastinum. Surgery forms the mainstay of therapy; however, thymic malignancies are sensitive to chemotherapy and radiation therapy also. Systemic chemotherapy is primarily used for treatment of metastatic or recurrent disease. Chemotherapy is also used as a component of multimodality treatment in the neoadjuvant setting with the aim of increasing the chances of achieving a complete surgical resection. In this article we outline various clinical trials that have been performed to evaluate the role of chemotherapy in the treatment of thymic malignancies.

The role of chemotherapy in advanced thymoma

BACKGROUND

Thymoma and thymic carcinomas are rare malignancies. Most thymomas and about one-third of thymic carcinomas can be cured with local therapy. The remainder of will be candidates for systemic therapy. Numerous retrospective trials confirm objective responses to a variety of single-agent and combination chemotherapeutic regimens.

METHODS

No prospective randomized comparison of regimens has been performed because of the rarity of the disease. This paper reviewed the literature of chemotherapy in advanced thymic malignancies.

RESULTS

Existing data suggest that anthracycline plus cisplatin regimens seem to demonstrate higher response rates and perhaps longer median survival times compared with nonanthracycline-containing regimens.

DISCUSSION

Thymic malignancies are sensitive to a broad spectrum of systemic agents. Thymic carcinoma has a distinct clinical presentation and worse therapeutic outcomes than thymoma. Despite reproducible high response rates in thymoma, durable complete remissions are rare. Thus, novel new therapeutic targets need to be identified and appropriate agents developed to have further impact on this disease.

Giant ossifying malignant thymoma in a child

We present the first reported case of an ossifying pediatric thymoma. Our patient was diagnosed with a massive thymoma replacing the whole of the left thoracic cavity. Percutaneous biopsy was attempted 3 times followed by an open incisional biopsy and adjuvant chemotherapy. Complete resection required a median sternotomy and a "trap door" thoracotomy after the tumor failed to respond to chemotherapy. Histology confirmed World Health Organization type B1 lymphocyte-rich thymoma, Masaoka stage I, with extensive osseous metaplasia.

New predictors of response to neoadjuvant chemotherapy and survival for invasive thymoma: a retrospective analysis

BACKGROUND

Cell-cycle protein (p27, p21, and p53) expression can predict response to neoadjuvant chemotherapy and prognosis in some neoplasms. This study evaluated whether these markers could also be effective in invasive thymoma during a multimodality treatment.

METHODS

Between 1989 and 2008, 33 patients with invasive thymoma underwent surgical resection after neoadjuvant chemotherapy. Expression of p27, p21, and p53 was assessed using immunohistochemistry in specimens retrieved pre and post chemotherapy. Factors influencing response to neoadjuvant chemotherapy and survival were investigated by univariate and multivariate analysis. Good response was defined as complete disappearance of tumor at imaging or necrosis >90% at pathologic studies.

RESULTS

Twelve patients disclosed an imaging good response. Complete resection was possible in 17 patients, 9 of whom had presented imaging good response and 11 of whom had revealed pathologic good response. On univariate analysis both imaging and pathologic poor responses were significantly associated with incomplete resection (P = 0.04 and P = 0.03, respectively) and preneoadjuvant triple combination of p27 low, p21 low, and p53 high expressions (P = 0.001 and P < 0.0001, respectively), the last factor being the only one selected on logistic regression (P = 0.01 and P = 0.005, respectively). Long-term survival analysis was negatively influenced by triple combination of p27, p21, and p53 (P < 0.0001) and incomplete resection (P < 0.0001), which were also selected on Cox's regression (P = 0.004 and P = 0.02, respectively).

CONCLUSIONS

The triple combination of p27 low, p21 low, and p53 high expressions was the most significant predictor of imaging and pathologic poor responses to neoadjuvant chemotherapy in invasive thymoma. This combination together with incomplete resection was also the most significant negative predictor of long-term survival.

Thymomas: review of current clinical practice

Thymomas are the most common tumors of the mediastinum. The introduction of multimodality treatment strategies, as well as novel approaches to the diagnosis of these tumors, has led to changes in the clinical management of thymomas. Here we review the literature for current clinical practice in the diagnosis, management, and treatment of thymomas.

Optimal therapy for thymoma

Thymoma is the most common tumor of the anterior mediastinum. This tumor is associated with unique paraneoplastic syndromes (myasthenia gravis, pure red cell aplasia, hypogammaglobulinemia, and other autoimmune diseases). The rarity of this tumor has somewhat obscured the optimal treatment. Although the histologic classification of thymoma has remained a subject of controversy for many years, the WHO classification system, published in 1999, appeared to be an advance in our understanding of thymoma. The optimal treatment for thymoma depends on its clinical stage. Surgery remains the mainstay of treatment for thymic epithelial tumors. Thymomas also have a high response rate to chemotherapy or radiotherapy. Only surgical resection is performed for patients with stage I (non-invasive) thymoma. The value of postoperative radiotherapy in completely resected stage II or III tumors is questionable. Multimodality therapy involving surgery, chemotherapy and radiotherapy appears to increase the rate of complete resection and survival in advanced (stage III and IV) thymomas.

Surgical treatment of thymoma

PURPOSE

A case report is presented of a 66-year-old white woman with a 3-month history of atypical chest pain and shortness of breath.

METHODS

A lateral chest radiograph demonstrated an anterior mediastinal density. A subsequent computed tomography (CT) scan revealed a mass in the right anterolateral mediastinum. Fine-needle aspiration (FNA) revealed tumor cells positive for cytokeratin and negative for leukocyte common antigen.

RESULTS

The differential diagnosis at that time included thymoma versus thymic carcinoid. She underwent a median sternotomy with complete thymectomy. The pathology revealed a large thymoma with microinvasion into the surrounding adipose tissue. She had an uneventful postoperative course and later underwent adjuvant radiation therapy.

CONCLUSIONS

Surgical treatment of thymoma is discussed, with emphasis on diagnosis and treatment. Although some patients may present with symptoms caused by involvement of surrounding structures, most thymomas are discovered incidentally on chest radiograph. Various diagnostic procedures can aid the surgeon in ruling out other neoplasms, such as lymphoma or germ cell tumors. Prognosis is not based on histology, but on the tumor's gross characteristics at operation. Benign tumors are noninvasive and encapsulated. All patients with potentially resectable lesions should undergo en-bloc excision. Radiation or chemotherapy should be instituted in more advanced tumors.

A single institutional experience of thymic epithelial tumours over 11 years: clinical features and outcome and implications for future management

Thymic epithelial tumours (TETs), the most common tumour of the anterior mediastinum, are epithelial neoplasms of the thymus with a wide spectrum of morphologic features. We retrospectively analysed clinical features of TET and the correlation of World Health Organisation (WHO) histologic classification and Masaoka staging system with different treatment modalities in 195 patients, from 1995 to 2005. According to the Masaoka's staging system, there were 78 (40.0 %) patients with stage I, 38 (19.5%) with stage II, 41 (21.0%) with stage III, 38 (19.5%) with stage IV. All patients were reclassified according to the WHO criteria as follows: Type A (n=9, 4.6%), AB (n=37, 18.9%), B1 (n=29, 14.8%), B2 (n=48, 24.6%), B3 (n=40, 20.5%), C (n=32, 16.4%). There was a fairly good correlation between Masaoka staging and WHO histotype (P<0.05). However, in multivariate analysis, the tumour stage and WHO histotype were two independent factors separately for predicting overall survival (P<0.001, P<0.001, respectively). Thus, both Masaoka stage and WHO histotype should be considered in risk stratification of therapy for TET patients. Patients with completely resected types B2, B3 and C and adjuvant radiotherapy (n=57) had more favourable disease-free and overall survival as compared with those without adjuvant treatment (n=20) (P=0.015, 0.015, respectively). Given that the predominant sites of recurrence after surgery was pleura/pericardium and lung, and the fact that complete resection was a significant influential factor for survival at log–rank test, an active investigation of newer treatment strategies such as neoadjuvant treatment to improve the resectability and development of optimal adjuvant treatment modality is a high priority especially for those with high-risk for recurrence or in patients with advanced stage disease.

Topoisomerase 2α plays a pivotal role in the tumor biology of stage IV thymic neoplasia

BACKGROUND

Microsatellite studies in histologic types B3 and C thymic neoplasia detected gains on chromosome 17q, which contains the Her-2/neu and its juxtaposed topoisomerase 2alpha (T2alpha) genes. The study aimed to evaluate their impact on tumor biology and survival of advanced thymic neoplasia patients.

METHODS

From 1991 to 2005, 36 consecutive stage IV thymic carcinoma patients were treated, 18 men and 18 women, aged 11 to 84 years. There were 22 thymic carcinoma, 13 type B3, and 1 type B2 thymoma. Patients received treatment consisting of surgical resection, combination chemotherapy with the CAP (cyclophosphamide, Adriamycin, cisplatin) regimen, or radiation therapy potentiated by high-dose weekly 5-fluorouracil infusion. Permutations of these 3 treatment modalities were prescribed as necessary.

RESULTS

T2alpha gene amplification was detected in 4 of 14 thymic carcinoma and 1 of 15 type B3 thymoma. Three thymic carcinoma patients had Her-2/neu coamplification and these 3 patients had rapidly growing tumor and extensive disease at initial diagnosis. CAP was prescribed in 28 patients and 20 patients responded (response rate, 71.4%, 95% confidence interval [CI]: 52.8% to 85%); all responders overexpressed (> or = 10% nuclei positive) the T2alpha protein, whereas 4 nonresponders had very low expression. T2alpha overexpression predicts CAP response, and its absence predicts resistance (P = .001). Overall survival was significantly prolonged if the tumor was resectable (P = .001), of type B3 histology (P = .0039), and had no Her-2 gene amplification (P = .0081).

CONCLUSION

T2alpha and Her-2/neu genes play a pivotal role in the tumor biology, CAP response, and survival of advanced thymic neoplasia patients.

Multidisciplinary Treatment for Advanced Invasive Thymoma with Cisplatin, Doxorubicin, and Methylprednisolone

BACKGROUND AND OBJECTIVES

Advanced invasive thymomas are not usually manageable by surgical resection and radiotherapy. We reviewed our experience with a multidisciplinary approach and evaluated chemotherapy in the treatment of invasive thymoma.

PATIENTS AND METHODS

Seventeen consecutive patients with invasive thymoma were treated with multimodality therapy consisting of chemotherapy, surgery, and/or radiotherapy. Four patients had stage III disease with superior vena cava invasion, nine had stage IVa disease, and four had stage IVb disease. The chemotherapy regimen consisted of cisplatin, doxorubicin, and methylprednisolone (CAMP). Chemotherapy was administered in a neoadjuvant setting to the 14 patients and in an adjuvant setting to the remaining three patients. Surgical resection was intended in all patients. After those treatments, chemotherapy and/or radiation therapy were performed.

RESULTS

All but one of the 14 patients with induction chemotherapy responded to the CAMP therapy, and the response rate was 92.9%. Seven of these patients underwent complete remission after surgical resection and chemoradiotherapy, and the others underwent partial remission. All three patients treated with surgical resection and then chemotherapy with or without radiotherapy also achieved complete remission. Tumor progression after multimodality therapy occurred in 10 patients. After retreatment, eight of these patients were alive at the time of analysis, with a median survival time after recurrence of 30 months. The 5- and 10-year overall survival rates for all patients were both 80.7%. The major side effect of CAMP therapy was acceptable neutropenia.

CONCLUSIONS

CAMP therapy was highly effective for invasive thymomas, and the multimodality therapy containing this chemotherapy brought about good disease control in the majority of patients. We believe that this multidisciplinary treatment with CAMP therapy, surgery, and radiotherapy is a justifiable initial treatment for patients with advanced invasive thymoma. Furthermore, appropriate treatments are essential for the long-term survival of patients with recurrences after multimodality therapy.