Adenoid cystic carcinoma of the trachea and main-stem bronchus. A clinical, histopathologic, and immunohistochemical study

Twelve cases of adenoid cystic carcinoma of the trachea and main-stem bronchus were histologically analyzed, and the results were examined with reference to the growth pattern of the tumor and the prognosis. The tumors were histologically classified into tubular, cribriform, and solid subtypes. Three histologic grades were established: grade I, tumors with tubular and cribriform subtypes but without solid subtype; grade II, tumors with tubular and cribriform subtypes in which the solid subtype comprised less than 20% of the area; grade III, tumors in which the solid subtype comprised more than 20% of the area. Three gross infiltrating types were established: type I, entirely intraluminal; type II, predominantly intraluminal; type III, predominantly extraluminal. In most cases histologic grade correlated with gross tumor type; that is, grades, I, II, and III were grossly types I, II, and III, respectively. The tumors infiltrating along the tracheobronchial wall were of the tubular or cribriform subtype, but not of the solid subtype. In two patients who died of distant metastasis, the histologic studies revealed the solid subtype. Immunohistochemical analysis demonstrated that the tubular subtype was the most differentiated form and the solid subtype, the most undifferentiated form. The histologic subtype of adenoid cystic carcinoma of the tracheobronchial tree was an important factor in the growth pattern of the tumor and the prognosis.     

Intrapulmonary Schwannoma

A 58-year-old woman was admitted due to an abnormal shadow on chest X-ray, without any symptoms. Chest computed tomography showed a round mass in the anterior segment of the right upper lobe. Segmentectomy was performed and histopathological examination revealed a primary neurogenic tumor of Schwann cell origin. Immunohistochemical staining demonstrated the presence of S-100 protein in the tumor cells. We present a case of intrapulmonary schwannoma and review 62 cases of primary schwannoma of the lung.     

Circular dichroism of poly{γ-[2-(9-carbazolyl)ethyl] L-glutamate} in dilute solution and in solid state

Circular dichroism (CD) and ultraviolet absorption (UV) spectra were measured for poly{γ-[2-(9-carbazolyl)ethyl] L -glutamate} (PCLG), whose side chain chromophore has three π – π^* transitions in a wavelength region not overlapping with the n – π^* transition of the main chain peptide group. For the dilute solution in any given helicogenic solvent, the observed CD sign had a good correlation to the polarization direction of the π – π^* transitions. On the other hand, a concentrated solution with a concentration of ca. 15 wt.-% was found to form a liquid crystalline phase, which was probably nematic at room temperature. The CD spectral profiles of the cast film of the polypeptide were quite different from that of the dilute solution. Origins of the optical activity are discussed.     

Protein 1 and Clara cell 10-kDa protein distribution in normal and neoplastic tissues with emphasis on the respiratory system

Thirty-six different normal tissues and 13 different malignant epithelial tumours, were examined immunohistochemically for the presence of protein 1 (P1) and Clara cell 10-kDa protein (CC10). Adenocarcinomas of the lung were also examined for the expression of pulmonary surfactant apoprotein using a monoclonal antibody (PE-10). The staining results of P1 and CC10 were almost identical both in normal tissues and in malignant tumours. In normal lung, Clara cells were strongly positive for both P1 and CC10. In addition, some goblet cells and non-ciliated non-mucus cells in the upper airways were moderately positive for both proteins. In the malignant tumours, some lung cancers were positive for P1 and CC10, both of which were positive in the same tumour cells on sequential sections. In 117 lung cancers, P1 and CC10 were positive in 10.2% of adenocarcinomas, 20.5% of squamous cell carcinomas, and 12.5% of large cell carcinomas. PE-10 stained positively in 65.3% of adenocarcinomas, a frequency significantly higher than that of P1 and CC10 (P<0.01). These results suggest that P1 and CC10 are nearly identical proteins, that both are useful markers of Clara cells, and that many pulmonary adenocarcinomas express surfactant apoprotein rather than Clara cell proteins.     

Mixing collagen with fibrin glue to strengthen the sealing effect for pulmonary air leakage

BACKGROUND: To strengthen the sealing effect of fibrin glue for pulmonary air leakage, atelocollagen was mixed with the glue and the mixing effect was examined. METHODS: A mixture of fibrinogen and thrombin with atelocollagen was used as a test sample. The concentrations of atelocollagen were adjusted to levels of 0%, 0.375%, 0.75%, 1.1%, and 1.5%. We next performed air leakage tests on a plastic cap with pin holes and swine lung and also measured the elasticity and the adhesion strength. RESULTS: The pressure required to rupture the sealant on a plastic cap with pin holes increased as the concentration of atelocollagen increased, and the bursting pressures were significantly higher in the glue with 0.75%, 1.1%, and 1.5% of atelocollagen than in the glue without atelocollagen (p < 0.01 and p < 0.001). The air leakage pressure on the swine lung was significantly higher in the glue with 0.375%, 0.75%, and 1.1% of atelocollagen than in the glue without atelocollagen (p < 0.05 and p < 0.01), and it was the highest with 0.75%. The elasticity of the glue significantly increased as the concentration of atelocollagen increased (p < 0.001). However, the adhesion strength of the glue significantly decreased as the concentration of atelocollagen increased (p < 0.05 to p < 0.001). CONCLUSIONS: The mixing of atelocollagen with fibrin glue more effectively sealed pulmonary air leakage due to an increased elasticity of the glue while its adhesion strength decreased. The optimal concentration of atelocollagen in the fibrin glue to obtain the best sealing effect was 0.75%.     

Radiofrequency ablation of pulmonary tumors and normal lung tissue in swine and rabbits

OBJECTIVE: The purpose of the present study was to examine the following during radiofrequency ablation (RFA): (1) the risk of hemorrhage from intrapulmonary large vessels; (2) the risk of incomplete ablation of pulmonary tumors; and (3) the late effect on lung tissue. MATERIALS AND METHODS: A 17-gauge, cool-tip-type radiofrequency electrode was used. The damage to the vessels and bronchi was examined by the injection of a colored silicone rubber, a liquid compound that hardens after injection. To examine the risk of hemorrhage from intrapulmonary large vessels, RFA was conducted at eight sites near the central pulmonary vessels in two swine. To examine the risk of an incomplete ablation for pulmonary tumors, 10 pulmonary nodules were made from a gelatin mixture in another two swine and were treated by RFA. To examine the late effect on lung tissue, RFA was conducted on the peripheral lung in 10 rabbits, and then the ablated regions were examined on days 1, 7, 14, 21, and 28 after RFA. RESULTS: The use of colored silicone rubber enabled us to examine the intrapulmonary vessels and bronchi for opening and leakage. RFA did not damage the large intrapulmonary vessels, even when they were located within the ablated regions. Lung tissue surrounding the gelatin nodules was hardly ablated over its entire circumference. Six of 10 gelatin nodules (60%) showed nonablated areas on the peripheral edges of the nodules. From 21 days after RFA, the ablated rabbit lung formed noninfectious cavities by communicating with the surrounding bronchi. CONCLUSION: It was improbable for hemorrhage to occur even when RFA was conducted near the large intrapulmonary large vessels. Because an incomplete ablation that left tumor cells at the site of ablation could occur during surgery due to the difficulty of ablating the entire tumor circumference, CT scan-guided RFA would be preferable to a surgical approach for making a safe margin. Cavity formation can occur beginning 21 days after RFA, which should be carefully followed up in a clinical setting to identify infection, especially in immunocompromised patients.     

Omission of mediastinal lymph node dissection in lung cancer: its techniques and diagnostic procedures.

To reduce or omit a mediastinal lymph node dissection in the patients with clinical stage I non-small cell lung cancer (NSCLC), several authors examined the prevalence of metastatic sites of lymph nodes. Because lymphatic drainage usually heads for the upper mediastinum in upper lobe cancer and for the lower mediastinum in lower lobe cancer, upper and lower mediastinal lymph node dissection could be reduced in lung cancers of lower lobe and upper lobe. By using sentinel node (SN) navigation surgery, it is possible to omit mediastinal lymph node dissection. Radiological findings are also useful to determine reduction of mediastinal lymph node dissection. In clinical stage Ia adenocarcinomas that show ground glass opacity (GGO) findings on computed tomography (CT) or negative for fluorodeoxyglucose accumulation on positron emission tomography (PET), mediastinal lymph node dissection can be omitted, because these types of adenocarcinomas rarely metastasize to the lymph nodes. By using these procedures, mediastinal lymph node dissection can be reduced or omitted with little risk of local recurrence.