Keiichi Suemasu

The Importance of Surgery to Non-Small Cell Carcinoma of Lung with Mediastinal Lymph Node Metastasis

In the past 25 years, 1,654 patients with non-small cell cancer underwent resection at National Cancer Center Hospital, Tokyo. A comparative study has been made of 5-year survival of patients who had pulmonary resection with and without mediastinal lymph node dissection. There were 426 patients (25.8% of the total) with N2 M0 disease. Of these, 345 underwent pulmonary resection with mediastinal lymph node dissection. The 5-year survival in this group was 15.9% (T1 N2 M0, 30.0%; T2 N2 M0, 14.5%; and T3 N2 M0, 12.9%). In the remaining 81 patients, who did not have mediastinal lymph node dissection, 5-year survival was 6.7%. Of the 426 patients with N2 M0 disease, 242 were select patients who underwent a curative operation with an overall 5-year survival of 19.2%. Sixty-six of them had squamous cell carcinoma and a 5-year survival of 30.8%; 153 had adenocarcinoma and a survival of 16.0%; 14 had large cell carcinoma and a survival of 12.8%; and 9 had adenosquamous cell carcinoma, and none survived 5 years. To improve the end results, it is important to perform as many curative operations with mediastinal lymph node dissection as possible. Histological cell type and tumor status must be taken into consideration.

Squamous cell carcinoma of the thymus. An analysis of eight cases.

Right cases of squamous cell carcinoma of the anterior mediastinum, most likely derived from the thymus, are presented. Seven were male and one female ranging in age from 39 to 65 years: the average was 55.5 years. There were no cases associated with any paraneo-plastic syndromes. They possessed common morphological characteristics. Grossly, the tumors resembled malignant thymoma. Invasion of the lung and metastases to regional lymph nodes were frequent. Often observed microscopically were foci of sharply defined kcratinization resembling Hassalls corpuscles, no radial arrangement of tumor cells at the periphery of nests, and broad, fibrotic, or hyalinized stroma. Admixture of a few lymphoid cells and some features transitional to thymoma were also observed in some parts of tumors. However, undoubtedly carcinomatous areas were present in some or large parts of all the tumors, where individual cells possessed a vesicular nucleus and a prominent round nucleolus. These features were distinct from those of bronchogenic squamous cell carcinoma and other thymic tumors, although they appeared to be related to thymoma. Treatment of choice is radical surgery and postoperative radiotherapy, because of relatively high radiosensitivity. Prognosis of patients was relatively good. From analyses of cases, it is concluded that squamous cell carcinoma of the thymus should be separated from ordinary thymoma of the epithelial type, and that squamous cell carcinoma involving both the thymus and lungs should be carefully examined for the primary site of growth.

Histopathologic prognostic factors in adenocarcinomas of the peripheral lung less than 2 CM in diameter

The histologic prognostic factors of pulmonary adenocarcinomas of the lung less than 2 cm in diameter were analyzed in 75 patients who had undergone surgical resection. The pathologic stage, lymph node involvement, and pleural involvement were found to be the major determinants of prognosis (P < 0.01). In addition, other single factors, such as tumor differentiation (P < 0.01), vascular invasion (P < 0.01), the degree of collagenization in the fibrotic focus (P < 0.01), the standard deviation (SD) of nuclear areas (P < 0.05), and mitotic index (P < 0.05) correlated significantly with prognosis by the log‐rank test on the Kaplan‐Meier survival curves of these factors. Patients with dense infiltration of “T‐zone histiocytes” survived significantly longer than those with less infiltration (P < 0.05). Coxs proportional hazard general linear model analysis showed the importance of factors, such as lymph node or pleural involvement and the SD of nuclear area, when the pathologic stage was excluded, and of the mitotic index when all four factors were excluded to emphasize the cellular characteristics. It is possible to predict the postoperative prognosis of patients with small pulmonary adenocarcinoma more precisely by combination of the above histopathologic factors.

What is the advantage of a thoracoscopic lobectomy over a limited thoracotomy procedure for lung cancer surgery

BACKGROUND To clarify any advantages of video-assisted thoracoscopic surgery (VATS) over anterior limited thoracotomy (ALT) for lobectomy in lung cancer, we compared the two procedures in a retrospective analysis. METHODS Sex- and age-matched (+/- 5 years) lung cancer patients in clinical stage I who underwent lobectomy by means of VATS (n = 33) or ALT (n = 33) were compared in terms of the number of resected lymph nodes, operating time, intraoperative blood loss, duration of postoperative chest tube drainage, and chest pain. Pain was evaluated using a visual analog scale and analgesic requirements. Vital capacity (VC), respiratory muscle strength, and results of a 6-minute walking (6 MW) test were also compared preoperatively and 1 and 2 weeks postoperatively. RESULTS Compared with the ALT group, the VATS group experienced less pain between postoperative day (POD) 1 and POD 7 (p < 0.05 to 0.001) and had lower analgesic requirements up to POD 7 (p < 0.001). However, there were no significant differences in pain on POD 14. There were also no significant differences in intraoperative factors or in the postoperative impairment of VC, respiratory muscle strength, and 6 MW test results. CONCLUSIONS Although VATS lobectomy reduces chest pain during the first week after surgery compared with ALT, this advantage is lost within 2 weeks. Both techniques result in similar impairments of pulmonary function, respiratory muscle strength and walking capacity. Therefore, if curative resection of lung cancer by VATS would be technically difficult for any reason, including the surgeons skill and experience, a limited open thoracotomy would be preferable from the standpoints of safety and the patients prognosis.

Expression of vimentin in surgically resected adenocarcinomas and large cell carcinomas of lung

The expression of vimentin in pulmonary carcinomas was studied in 285 cases of surgically resected lung cancer from our hospital files. Formalin fixed, paraffin-embedded sections were studied by immunoreactive staining techniques using two monoclonal antibodies against vimentin. Cases demonstrating vimentin positivity by the avidin-biotin-peroxidase method included 11 of 129 adenocarcinomas studied (8.5%), and 15 of 61 large cell carcinomas studied (24.6%). Vimentin expression was not seen in any of the 51 squamous cell carcinomas or 35 small cell carcinomas in our series. The positive cases of adenocarcinoma were in moderately and poorly differentiated cancers. Four of the eight giant cell carcinomas (50%) demonstrated vimentin expression. All cases that exhibited vimentin positivity were studied for cytokeratin expression. Coexpression of vimentin and cytokeratin was demonstrated not only within the same tumor but also within the same cells in some cases stained by double antibody technique, including both adenocarcinomas and large cell carcinomas. Similar immunoreactive methods were also applied to sections from human lung cancer transplants grown in the nude mouse. Of 28 tumors studied, four of 11 adenocarcinomas (36%) and all 4 large cell carcinomas demonstrated coexpression of vimentin and cytokeratin, while none of the five squamous cell carcinomas or eight small cell carcinomas expressed vimentin.

Prognostic significance of [18F]fluorodeoxyglucose uptake on positron emission tomography in patients with pathologic stage I lung adenocarcinoma

[18F]Fluoro‐2‐deoxyglucose uptake on positron emission tomography (FDG‐PET) has been frequently used for diagnosis and staging of lung cancer. The prognostic significance of FDG uptake on PET was evaluated in patients with pathologic Stage I lung adenocarcinoma (tumor stages were based on the TNM classification of the International Union Against Cancer).

Differentiating between atypical adenomatous hyperplasia and bronchioloalveolar carcinoma using the computed tomography number histogram

BACKGROUND Both atypical adenomatous hyperplasia (AAH) and bronchioloalveolar carcinoma (BAC) appear as ground glass opacity (GGO) lesions by computed tomography (CT) and are sometimes difficult to differentiate. To aid distinction between the two, we examined their CT number histograms. METHODS Histograms of pixel CT numbers were made for AAH (n = 9) and nonmucinous BAC (n = 8), and the peak and mean CT numbers on the histogram were quantified. RESULTS Although there was no significant difference in lesion size between AAH and BAC, all AAHs were less than or equal to 1 cm in diameter. All AAHs and BACs manifested one histogram peak. Both the peak and mean CT numbers on the histogram were significantly lower for AAH than for BAC (p < 0.001). However, the degree of overlap between AAH and BAC was less for the peak CT number than for the mean CT number. CONCLUSIONS The peak CT number on the histogram can help the radiologic differentiation between AAH and BAC. GGO lesions less than or equal to 1 cm in diameter that are diagnosed as AAH from the CT number histogram can be safely followed by CT.

Difference in the Impairment of Vital Capacity and 6-Minute Walking After a Lobectomy Performed by Thoracoscopic Surgery, an Anterior Limited Thoracotomy, an Anteroaxillary Thoracotomy, and a Posterolateral Thoracotomy

Abstract.Purpose: Postoperative vital capacity (VC) and the 6-min walking (6MW) test were used to compare the differences in impairment of the pulmonary function and walking capacity in patients undergoing a lobectomy by video-assisted thoracoscopic surgery (VATS), an anterior limited thoracotomy (ALT), an anteroaxillary thoracotomy (AAT), or a posterolateral thoracotomy without muscle sparing (PLT). Methods: The study was a retrospective analysis. Lung cancer patients who underwent a lobectomy by VATS, ALT, AAT, or PLT (28 in each group) were matched by sex and age (±5 years). VC was measured before surgery and at 1, 2, 4, 12, and 24 weeks after surgery. The distance covered during the 6MW test (6MWD) was measured before surgery and in a postoperative test 1 week after surgery. Results: Compared with the VATS, ALT, and AAT groups, PLT patients showed a significant impairment of VC from 1 to 24 weeks after surgery (P < 0.05–0.001) and also a significant impairment of 6MWD 1 week after surgery (P < 0.01–0.001). The AAT group showed a significant impairment of 6MWD 1 week after surgery compared with the VATS and ALT groups (P < 0.001 and P < 0.05, respectively). There was no significant difference in the impairment of either VC or 6MWD between VATS and ALT. Conclusions: The PLT without a muscle sparing procedure therefore cannot be recommended for general lung cancer surgery because of the impairment of both walking capacity and pulmonary function which continues long after surgery. VATS and ALT are better procedures than AAT regarding the recovery of walking capacity early after surgery. VATS and ALT are similar to each other regarding the impairment of pulmonary function and walking capacity after surgery.

Double stenting for esophageal and tracheobronchial stenoses

BACKGROUND We examined the complications and outcomes of placing stents for both esophageal and tracheobronchial stenoses. METHODS We placed stents for both esophageal and tracheobronchial stenoses in 8 patients (7 with esophageal cancer and 1 with lung cancer). Covered or noncovered metallic stents were used for the esophageal stenoses, except in 1 patient treated with a silicone stent. Silicone stents were used for the tracheobronchial stenoses. The grades of esophageal and tracheobronchial stenoses were scored. RESULTS All patients experienced improvement of grades of both dysphagia and respiratory symptoms after stent therapy. The complications were: (1) 2 patients suffered respiratory distress after placement of the esophageal stent because of compression of the trachea by the stent; and (2) 3 patients developed new esophago-tracheobronchial fistulae, and 2 patients had recurring fistula symptoms because of growth of preexisting fistulae after the stent placement, which were caused by pressure from the 2 stents. Despite the fistulae, the 5 patients treated with covered metallic stents did not complain of fistula symptoms, but 2 patients treated with noncovered metallic or silicone stents did complain. CONCLUSIONS For patients with both esophageal and tracheobronchial stenoses, a stent should be introduced into the tracheobronchus first. Because placement of stents in both the esophagus and tracheobronchus has a high risk of enlargement of the fistula, a covered metallic stent is preferable for esophageal cancer involving the tracheobronchus.

Fluoroscopy-assisted thoracoscopic resection of lung nodules marked with lipiodol.

BACKGROUND To localize small and deeply situated pulmonary nodules under thoracoscopy with roentgenographic fluoroscopy, we developed a marking procedure that uses both lipiodol and colored collagen. METHODS Pulmonary nodules were marked with 0.4 mL of lipiodol under computed tomography. The visceral pleura near each nodule was marked with 1 mL of colored collagen, ie, a mixture of atelocollagen and methylene blue. Nodules were marked more than 1 day before thoracoscopy. At thoracoscopy, C-arm-shaped roentgenographic fluoroscopy was used to detect the radiopaque nodules. Eighteen nodules in 16 patients were localized by this procedure. The nodules had an average diameter of 7 mm (range: 4 to 10 mm) and were located an average distance of 19 mm (range: 8 to 30 mm) from the pleural surface under computed tomographic measurement. RESULTS There were no complications from the marking procedure except for pneumothorax in 1 patient who required chest tube drainage for additional marking. All 18 nodules could be easily localized at thoracoscopy. The colored collagen revealed the pleura near the nodules. The lipiodol showed the nodules on the fluoroscopic monitor, which was used to guide the forceps to grasp the nodules. All of the nodules could be resected completely under thoracoscopy without adding minithoracotomy. The pathologic diagnosis was malignant tumor in 9 patients, atypical adenomatous hyperplasia in 3, and benign lesion in 4. CONCLUSIONS A marking procedure that uses both lipiodol and colored collagen can localize small and deeply situated pulmonary nodules under fluoroscopy and facilitate safe and successful thoracoscopic resection.