[Current problems in the diagnosis of malignant pleural mesothelioma]

The diagnosis of malignant pleural mesothelioma (MPM) is challenging although MPM is highly aggressive tumor. The current diagnostic gold standard is principally based on light microscopic examination of hematoxylin-eosin and immunohistochemical stains of large tissue sections. However, pathological diagnosis of MPM and classification of histological findings into 1 of the 3 subtypes (epithelial, sarcomatoid, biphasic) are difficult. We studied correlation between initial and final histological diagnosis retrospectively from the records of 21 cases with MPM from 1989 to 2005. The diagnosis of MPM was confirmed by histopathological examination of pleural tissue samples obtained by closed biopsy under computed tomography (CT) or ultrasonography-guided (5 cases), by biopsy under thoracoscopy with local anesthesia (9), by open biopsy via thoracotomy (2), and by video-assisted thoracoscopic surgery (VATS) [5] . Pleural biopsy under those diagnostic methods led to initial diagnosis of MPM in 15 of 21 cases (71.4%) . In 6 cases (28.6%) , initial diagnosis of MPM were not confirmed because of missing malignant tissue (1 case) and relatively small and sarcomatous element (5). In 2 cases examined by closed biopsy and in 3 examined by thoracoscopy under local anesthesia, initial diagnosis of MPM were not confirmed. To get the accurate diagnosis of MPM, obtaining large tissue samples in the initial examination by less invasive thoracoscopy is recommended.

[Extrapleural pneumonectomy for malignant pleural mesothelioma]

Standard treatment for malignant pleural mesothelioma (MPM) has not been proved yet. However, it has been recognized that extrapleural pneumonectomy (EPP) is a treatment of choice for epithelial MPM when combined with adjuvant therapies though EPP may frequently cause fetal complications. We report 5 cases of MPM with EPP, including 1 with good prognosis. Sixteen patients with MPM were admitted to our hospital between 1988 and 2003. Five patients underwent EPP, among which 4 were male and 1 female with ages from 46 to 61 years old. Histologically, 3 of them were epithelial and 2 were biphasic. Those with biphasic experienced acute respiratory failure and empyema, and died 81 days and 8 months after the surgery respectively. Among those with epithelial MPM, 2 are alive with no recurrence at 129 and 29 months after the surgery, and the other, followed by postoperative radiotherapy, died at 12 months. More cases with EPP or randomized controlled trials regarding EPP are necessary to evaluate efficacy of EPP for MPM.

[Thymoma with idiopathic thrombocytopenic purpura preceded by mediastinal hemorrhage; report of a case]

A 62-year-old female with chest and right shoulder pain admitted to a hospital. The chest computed tomography (CT) scan showed a large anterior mediastinum mass with pleural effusion. Thymoma was suspected by percutaneous aspiration biopsy of it. She was referred to our hospital for operation with decreased serum platelet count (7.0 x 10(4)/microliter) and high platelet associated IgG (PA IgG) level (119.5 ng/10(7) cells). Result of bone marrow examination was normal, splenomegaly was not seen and no other autoimmune disease was not detected, so she was thought to have ITP. After giving her intravenous high-dose gamma-globulin and her platelet count increased to normal, operation was done. Extended thymectomy was performed and postoperative course was uneventful. Pathological finding showed the mass mediastinum hematoma in thymus and there found a small thymoma. The hemorrhage was thought to occur from the thymoma. After the operation, her platelet count has not been changed to normal but remained lower level. Though myasthenia gravis, one of the autoimmune disease, improve after total thymectomy, it is thought that idiopathic thrombocytopenic purpura (ITP) could not improve after thymectomy.

[Is the bronchoscopic criteria of early lung cancer valid?]

We studied the validity of the bronchoscopic criteria of the early lung cancer using the surgical specimen excised between 1980 and 1999. Twenty-four cases with squamous cell carcinoma of the lung of clinical stage I were located subsegmental or more proximal bronchi and trachea, and the size less than 20 mm in greatest dimension. We histopathologically investigated the endoscopic features in relation to the width of superficial extent, the depth of cancer invasion, and lymph node metastasis. Tumors of the thickened type lesions less than 20 mm in greatest dimension showed no invasion into the cartilaginous layer and no lymph node metastasis. On the other hand, in the nodular and polypoid types, invasion beyond the cartilaginous layer was observed more or less, and lymph node metastasis was observed in 1 case. These cases would not be suitable for bronchoscopic (photodynamic) therapy. In conclusion, the bronchoscopic criteria of early lung cancer is valid in the thickened type, but not in the nodular type or polypoid type.

[A case of lung cancer underwent carinal resection with right upper lobectomy and carinal reconstruction with double-barreled anastomosis]

A 70-year-old male complaining cough was admitted to our hospital. Bronchoscopic examination revealed a tumor mass which occluded the orifice of the right upper lobe. Chest computed tomographic (CT) scans gave the image of tumor invasion at the carina. The pathological diagnosis of the tumor was squamous cell carcinoma. Operation was accomplished by right posterolateral thoracotomy approach through the fifth rib bed. The carinal resection with right upper lobectomy was followed by a double-barreled anastomosis of the right intermediate trunk and left main-stem bronchus into the carina. The operation was successfully performed and was considered curative. The length of resected airway measured 4.0 cm from tracheal line of resection to the divided the right intermediate trunk. Reinforcement of the anastomosis was not performed in this case. No postoperative complication occurred but mild ischemia of the anastomosis. The patient died of recurrent tumor in a year and 2 months after operation.

[Validity and controversies in the new postoperative pathologic TNM classification based on the results of surgical treatment of non-small cell lung cancer]

In 1997, the latest revision of the International System for Staging Lung Cancer was published. To validate the new pathologic TNM classification for non-small cell lung cancer (NSCLC), we analyzed the survival data of 455 patients who underwent pulmonary resection and pathologic staging at our institution from January 1980 through December 1999. The overall 5-year survival rate was 51.0%. Using the revised new stage classification, the survival rate for each stage was as follows; IA: 74.2%, IB: 66.4%, IIA: 56.0%, IIB: 51.8%, IIIA: 21.0%, IIIB: 16.0%, and IV: 0%. The current TNM classification well reflected the long-term prognostic hierarchy. There were significant differences in survival rates between patients with stage IA and IB, and between patients with stage IIB and IIIA. However, there was no significant difference between patients with stage IIA and IIB. No significant difference in survival was observed among patients with stage IIIA, stage IIIB, and stage IV. Five-year survival rate of 48.3% in the T3N0M0 category was significantly better than that of 21.0% found in the new stage IIIA. The survival of patients with intrapulmonary metastases in the same lobe (pm1) was not significantly better than that found in the stage IV. The TNM staging system accurately reflects the prognosis in NSCLC, but some stage definitions can be discussed.

[Five cases of surgically resected chronic expanding hematoma in the chest]

We report surgically treated 5 cases of chronic expanding hematoma in the chest. Three were male and two were female, aged 53 to 76. All patients except one who was thought to have an early stage of chronic expanding hematoma, had severe dyspnea due to compression of lung parenchyma or heart. Complete removal of the hematoma with fibrous capsule was done in two cases, but in three cases the hematoma was removed but the capsule was not because of severe adhesion to the surrounding structures. Post operative course was different to each other. One patient whose capsule was not removed completely have recurrent hematoma in the chest. The pulmonary or cardiac function were improved greatly except for the two cases; an early stage case and a recurrent case. We conclude that surgical removal is the first treatment for chronic expanding hematoma and complete removal of it with capsule is recommended.

[Surgical treatment for bilateral multiple lung cancers]

We reviewed 12 patients with contralateral bronchogenic carcinomas. Seven of them had metachoronous carcinomas and 5 had synchronous carcinomas. We treated 3 patients with lobectomy on both lungs, and 4 patients with lobectomy and segmentectomy, 2 patients with lobectomy and wedge resection, 2 patients with segmentectomy and thoracoscopic wedge resection, and one patient with lobectomy and ablation on each lung. Two patients who had lobectomy on both lungs were dead, one of whom of bronchofistula on operation and the other of respiratory failure 7 years and one month after second operation. The 5-year survival rate in 12 patients was 68.5% after first operation and 82.5% after second operation. We conclude that lobectomy on both lungs are not recommended because of high mortality rate and the limited resection should be considered to treat the other contralateral primary lung cancers. Because the patients with primary lung cancers have the possibility to suffer from new primary cancers in the different site of the lung, we need careful follow up of the patients after treatment on the first lung cancer.

[Analysis of the long-term survived patients with P-N2 non-small cell lung cancer]

We had 308 patients with P-N2 non-small cell lung cancer who were treated with pulmonary resection therapy from June 1975 to March 1994. We analysed 9 patients who could survive for 5 years and more after the operation. All of them were male and the mean age was 61.1 years. Histologically, 2 patients had adenocarcinoma and 7 patients had squamous cell carcinoma. The clinical staging was T2N1M0 in 2 patients, T1N2M0 in one, T2N2M0 in 2, T3N2M0 in 2, and T4N2M0 in 2 patients. The histopathological staging was T1 in one patient, T2 in 4, T3 in 3, and T4 in one patient. Three patients who had absolute non-curative operation (residual carcinoma on bronchial stump in 2 patients and residual mediastinal lymph nodes in one patient) were treated with radiation therapy after having operation. The one level mediastinal lymph node metastasis was found in 7 patients and multi-level one in 2 patients. Four patients out of nine are still alive and free from the cancer and 2 patients died of other unrelated disease. The patient who even have P-N2 non-small cell lung cancer with mediastinal lymph node involvement will live long after curative operation.

[Superior vena cava reconstruction combined with resection of mediastinal-pulmonary malignant tumors]

From 1988 to 1997, we experienced 5 cases of the superior vena cava (SVC) replacement with expanded polytetrafluoroethylene (ePTFE) grafts combined with resection of mediastinal or pulmonary malignant tumors. Two patients had lung cancer and three had invasive thymoma. Resection and reconstruction of the superior vena cava (SVC) were performed by application of a bypass graft between the innominate vein and the right atrium in two cases and a temporary bypass using a heparin-coated tube in three cases. Except in one patient who died of acute respiratory failure, no complication or occlusive symptom were observed postoperatively. Two patients remain healthy for 5 years 4 months and 2 years 7 months after operation. Three died 9 years, 5 months, and 110 days after operation respectively. In conclusion, ePTFE graft replacement or patch angioplasty of the SVC should be part of planning and execution of radical excision with curative intent of mediastinal or pulmonary malignant tumors.

[Probability of leaving cancer tissue unresected by limited operation in patients with peripheral, stage I non-small cell lung cancer]

To study the probability of leaving metastatic lymph nodes or intralobar metastasis unresected by limited surgery, we reviewed histopathologically 189 patients who had major pulmonary resection and complete lymph adenectomy for peripheral, p-T 1 or T 2 non-small cell lung cancer from 1975 to 1997 at our hospital. Lymph node involvements and or intralobar metastasis were found in 25 (26.0%) of 96 cases with tumor smaller than 3.0 cm and 44 (47.3%) of 93 cases with tumor larger than 3.0 cm. There was no difference between histological types of lung cancer. From this result, it was suggested that the risk of leaving cancer by limited operation would not be low. In conclusion, we believe that limited operation is not an alternative to the standard resection in patients with peripheral, stage I non-small cell lung cancer.

[Results of surgical treatment of T4 lung cancer]

A total of 381 patients with primary lung cancer including 30 cases of T4 lesion, were surgically treated at our hospital from June 1975 through July 1996. Extended resection was performed in 11 patients. The 5-year survival rate after operation for all cases of T4 lung cancer, including one with operative death was 15.2%. Six patients who had curative operation showed no significant prolonged survival when compared to 24 patients who resulted in non-curative operation, but the median survival time of the former was longer than that of the latter. Six patients survived over 3 years; malignant pleurisy and/or intrathoracic dissemination of lung cancer were existed in 3 cases of those patients. In conclusion, extended resection for patients with T4 lung cancer should be limited to patients who are expected to have curative operation.

[A case of malignant neuroepithelioma in the retroperitoneum]

Reported is a case of a malignant neuroepithelioma in the retroperitoneum. The patient was a 37-year-old male suffering from lumbago and edema of the lower extremities. After ultrasonography and a CT scan, a diagnosis of a retroperitoneal tumor was made and a surgical resection of the tumor was performed in October, 1985. The subsequent pathological diagnosis was malignant neuroepithelioma which showed epithelioid cell clusters that stained positively to NSE. Eleven months later, metastatic tumors were seen present in the lungs and the liver though they regressed markedly after adjuvant chemotherapy with ADM, CPM, and VCR. Forty-one months after his first operation, the patient continues to work. In this case, adjuvant chemotherapy has proved effective.