Jun-ichi Hayashi

Early results of a prospective study of limited resection for bronchioloalveolar adenocarcinoma of the lung.

BACKGROUND We reported that bronchioloalveolar adenocarcinoma (BAC) without active fibroblastic proliferation of the lung had no lymph node and pulmonary metastasis and had a favorable prognosis. However, there has been no prospective trial regarding limited pulmonary resection for this type of BAC. The purpose of this study is to confirm the effectiveness of limited resection for histologically confirmed BAC without active fibroblastic proliferation. METHODS From 1996 through 1999, 42 patients who had small peripheral lung tumors (< or = 20 mm), suspected of being BAC, were enrolled in this trial. The patient population consisted of 24 men and 18 women with a mean age of 58.4 years. Limited resection was completed when BAC, without both active fibroblastic proliferation and lymph node metastasis, was confirmed histologically by intraoperative pathologic examination. RESULTS Limited resection was completed in 36 patients, wedge resection in 34, and segmentectomy in 2 patients. In 6 patients, the procedure was converted into lobectomy because of pathologic invasive sign in 3, active fibroblastic proliferation in 1, and for other reasons in 2 patients. All patients have been followed for a median follow-up period of 30 months and are alive without sign of recurrence. CONCLUSIONS Our early results indicate that limited resection may be an acceptable alternative to lobectomy for histologically confirmed BAC without active fibroblastic proliferation.

Chromosome Binding Site of Latency-Associated Nuclear Antigen of Kaposi's Sarcoma-Associated Herpesvirus Is Essential for Persistent Episome Maintenance and Is Functionally Replaced by Histone H1

ABSTRACT Latency-associated nuclear antigen 1 (LANA1) of Kaposis sarcoma-associated herpesvirus (KSHV; human herpesvirus 8) persistently maintains a plasmid containing the KSHV latent origin of replication (oriP) as a closed circular episome in dividing cells. In this study, we investigated the involvement of chromosome binding activity of LANA1 in persistent episome maintenance. Deletion of the N-terminal 22 amino acids of LANA1 (ΔN-LANA) inhibited the interaction with mitotic chromosomes in a human cell line, and the mutant concomitantly lost activity for the long-term episome maintenance of a plasmid containing viral oriP in a human B-cell line. However, a chimera of ΔN-LANA with histone H1, a cellular chromosome component protein, rescued the association with mitotic chromosomes as well as the long-term episome maintenance of the oriP-containing plasmid. Our results suggest that tethering of KSHV episomes to mitotic chromosomes by LANA1 is crucial in mediating the long-term maintenance of viral episomes in dividing cells.

Pulmonary complications after surgical treatment of lung cancer in octogenarians

OBJECTIVE The purpose of this study was to analyze the risks associated with pulmonary resection for primary non-small cell lung cancer in octogenarians to help better management in these patients. METHODS We reviewed the outcome in our 35 patients aged 80 years and older who underwent pulmonary resection between 1981 and 1998. RESULTS The 5-year survival rate was 39.8%. The operative mortality rate was 0% and the morbidity 60%. There were ten major pulmonary complications, including respiratory insufficiency following bacterial pneumonia and sputum retention. Preoperative arterial pO(2) was significantly lower, A-aDO(2) was significantly higher, and operation time were significantly longer in patients with pulmonary complications after surgical treatment than in patients without complications (P<0.05). CONCLUSIONS Surgical treatment was not contraindicated for octogenarians with lung cancer. However, a relatively preoperative low arterial pO(2), high A-aDO(2), and long operation time may be risk factors for postoperative pulmonary complications in such patients. Surgeons must assess the preoperative data prudently to determine appropriate surgical strategy.

Efficacy and safety of extended thymectomy for elderly patients with myasthenia gravis

BACKGROUND The number of elderly patients who are diagnosed as myasthenia gravis (MG) is increasing in Japan. Although several factors affecting thymectomy have been well documented, few studies have focused on the efficacy and safety of thymectomy for elderly patients older than 60 years. METHODS We evaluated 94 patients with MG who underwent extended thymectomy, and divided them into two groups: patients younger than 59 years and patients older than 60 years. Preoperative patient data, pathology of the thymus, complications, and clinical outcome were evaluated. RESULTS In 69 young patients and 25 elderly patients, we observed no significant differences between the two groups with regard to preoperative data. Thymic hyperplasia was present in 45% of the young group and 16% of the elderly group. Remission and improvement rate were 40% and 57% in the young group and 8% and 75% in the elderly group, respectively. There were no serious complications, except one early death due to gastrointestinal bleeding in the elderly group. CONCLUSIONS We conclude that thymectomy is a safe and effective alternative for elderly patients with MG.

Combined warfarin and antiplatelet therapy after St. Jude Medical valve replacement for mitral valve disease

OBJECTIVES The clinical effect of combined warfarin and antiplatelet therapy on the incidence of stroke and postoperative complications after mitral (plus aortic) valve replacement was studied and compared with that observed with warfarin therapy alone. BACKGROUND It has been reported that combined warfarin and antiplatelet therapy may be effective but may be associated with an increased hemorrhagic risk. Therefore, definite benefits of the treatment in patients with an implanted prosthetic valve have not been clearly documented. METHODS Between January 1980 and December 1992, 195 patients with a St. Jude Medical valve at the mitral (plus aortic) position were assigned to receive treatment with either warfarin alone (125 patients) or warfarin plus antiplatelet agents (70 patients), such as dipyridamole (150 or 300 mg daily, 14 patients) or ticlopidine (200 or 400 mg daily, 56 patients). A minimal dose of aspirin (10 to 40 mg) was added (29 patients) if the maximal platelet aggregation rate by collagen was not reduced. The target thrombotest level was 10% to 20%. RESULTS The two treatment groups were similar with regard to gender and age distribution. The number of patients with atrial fibrillation, left atrial thrombus, history of previous stroke, simultaneous aortic valve operation and previously performed valve procedures were comparable in the two groups. Actuarial survival rate at 10 years was 98.3 +/- 1.7% (mean +/- SD) in the warfarin plus antiplatelet group and 90.3 +/- 3.2% in the warfarin group (p < 0.05 at 1 and 9 to 12 years). The actuarial stroke-free rate at 10 years was 95.3 +/- 3.4% and 84.3 +/- 3.8%, respectively (p < 0.05 by the generalized Wilcoxon test). The actuarial complication-free rate at 10 years was 89.4 +/- 4.3% and 67.9 +/- 4.8%, respectively (p < 0.05 by the generalized Wilcoxon test). No hemorrhagic complications were seen in the warfarin plus antiplatelet group. CONCLUSIONS The results strongly indicate the effectiveness and safety of combined warfarin plus antiplatelet treatment after St. Jude Medical valve replacement for mitral (plus aortic) valve disease.

Surgical strategy for clinical stage I non-small cell lung cancer in octogenarians

OBJECTIVE The purpose of this study was to determine whether lobectomy without radical systematic mediastinal lymphadenectomy (LA) is a satisfactory alternative surgical treatment for octogenarians with clinical stage I non-small cell lung cancer (NSCLC). METHODS From April 1985 through December 2001, 49 patients aged 80 years and older who underwent surgical treatment for clinical stage I NSCLC were reviewed. Lobectomy without radical systematic mediastinal LA was performed for 27 patients (LA0 group) and lobectomy with radical systematic mediastinal LA was performed for 22 patients (LA group). RESULTS The mortality rate was 0% in the LA0 group and 4.5% in the LA group. Five-year survival rate according to the type of surgery was 44.8% in the LA0 group and 55.5% in the LA group, a difference that was not significant (P=0.88). Although there was no significant statistical difference, postoperative pulmonary complication was more frequent in the LA group than in the LA0 group (32% in the LA group versus 11% in the LA0 group P=0.07). Five-year survival rates according to serum carcinoembryonic antigen (CEA) levels were 0% for patients with elevated CEA levels (n=9) and 56.5% for patients with normal CEA levels (n=40) (P<0.01). CONCLUSION Lobectomy without radical systematic mediastinal LA appears to be a satisfactory surgical procedure for octogenarians with clinical stage I NSCLC. However, mediastinoscopy is necessary in such octogenarians if their serum CEA level is elevated so that the precise clinical stage can be determined and an accurate prognosis can be given.

Expression of the peptide hormone hepcidin increases in cardiomyocytes under myocarditis and myocardial infarction

The micronutrient iron is an essential component that plays a role in many crucial metabolic reactions. The peptide hormone hepcidin is thought to play a central role in iron homeostasis and its expression is induced by iron overloading and inflammation. Recently, hepcidin has been reported to be expressed also in the heart; however, the kinetics of altered hepcidin expression in diseases of the heart remain unknown. In this study, we examined cardiac expression of hepcidin in rat experimental autoimmune myocarditis (EAM), human myocarditis and rat acute myocardial infarction (AMI). In rat EAM and AMI hearts, hepcidin was expressed in cardiomyocytes; ferroportin, which is a cellular iron exporter bound by hepcidin, was also expressed in various cells. Analysis of the time course of the hepcidin to cytochrome oxidase subunit 6a (Cox6a)2 expression ratio showed that it abruptly increased more than 100-fold in hearts in the very early phase of EAM and in infarcted areas 1 day after MI. The hepcidin/Cox6a2 expression ratio correlated significantly with that of interleukin-6/gamma-actin in both EAM and AMI hearts (r=0.781, P<.0001 and r=0.563, P=.0003). In human hearts with histological myocarditis, the ratio was significantly higher than in those without myocarditis (0.0400+/-0.0195 versus 0.0032+/-0.0017, P=.0045). Hepcidin is strongly induced in cardiomyocytes under myocarditis and MI, conditions in which inflammatory cytokine levels increase and may play an important role in iron homeostasis and free radical generation.

Masaoka Stage and Histologic Grade Predict Prognosis in Patients With Thymic Carcinoma

BACKGROUND Thymic carcinoma is a rare tumor. Limited data are available regarding the effectiveness of treatment and the prognosis of thymic carcinoma. The present study aimed to clarify the prognostic factors in patients who underwent resection. METHODS The study retrospectively reviewed 21 patients (15 men, 6 women) with thymic carcinoma who had undergone resection at Niigata University Hospital. RESULTS Masaoka stage was II in 4 patients, III in 9, IVa in 2, and IVb in 6. Histologic subtypes were squamous cell carcinoma in 14 patients, adenocarcinoma in 2, atypical carcinoid in 3, and undifferentiated carcinoma in 2. Histologic grade by degree of differentiation was low in 4 tumors, intermediate in 12, and high in 5. Treatment comprised resection alone in 6 patients and resection along with multimodal therapies in 15. Complete resection was achieved in 14 (67%). Eight patients died of tumor. Recurrence was documented in 7 of 14 patients with complete resection, and 5 received additional treatment. The overall 5-year survival rate was 61.1%, and the disease-free 5-year survival rate was 66.8% for the 14 with complete resection. By multivariate analysis, Masaoka stage and histologic grade were significant independent prognostic factors for overall survival. CONCLUSIONS The surgical outcome of patients with thymic carcinoma depends on the Masaoka stage and histologic grade. Patients with early Masaoka stage and low or intermediate histologic grade had favorable prognoses.

Different Subtypes of Human Lung Adenocarcinoma Caused by Different Etiological Factors : Evidence from p53 Mutational Spectra

Human lung adenocarcinomas are only relatively weakly associated with tobacco smoke, and other etiological factors need to be clarified. These may also vary with the histopathology. Because the p53 mutation status (frequency and spectrum) of a carcinoma can provide clues to causative agents, we subclassified 113 adenocarcinomas into five cell types: hobnail, columnar/cuboidal, mixed, polygonal, and goblet (54, 23, 18, 13, and 5, respectively) and investigated relationships with p53 mutations and smoking history. In the hobnail cell type, a low mutational frequency (37%) and a high proportion of transitions (65%), especially G:C to A:T transitions at CpG dinucleotides (45%) associated with spontaneous mutations, were found with a weak relation to tobacco smoke. In contrast, a high mutation frequency (70%) with a higher proportion of transversions (50%), especially G:C to T:A (44%) on the nontranscribed DNA strand, caused by exogenous carcinogenic agents like tobacco smoke, were observed for the columnar cell type, as with squamous cell carcinomas. These results indicate that two major subtypes of lung adenocarcinoma exist, one probably caused by tobacco smoke, and the other possibly due to spontaneous mutations. For the prevention of lung adenocarcinomas, in addition to stopping tobacco smoking, the elucidation of endogenous mechanisms is important.

Complications associated with pulmonary resection in lung cancer patients on dialysis

BACKGROUND There are few studies available investigating the perioperative problems experienced by lung cancer patients on dialysis undergoing pulmonary resection. METHODS A retrospective review of 7 patients on dialysis undergoing pulmonary resection for lung cancer was performed. RESULTS The patient population consisted of 7 men, with a mean age of 59.9 years. The underlying kidney disease was glomerulonephritis in 5 patients and nephrosclerosis in 2. The mean levels of blood urea nitrogen and serum creatinine were 70.7 mg/dL and 9.4 mg/dL, respectively. Histologic diagnoses were adenocarcinoma in 2 patients and squamous cell carcinoma in 5. Standard lobectomy with lymph node dissection was performed in all cases. There was one operation related death due to pulmonary edema and subsequent development of pneumonia. There were two cases of sputum retention and four of hyperkalemia. One patient died of cerebral bleeding that occurred during dialysis 2 months postoperatively. CONCLUSIONS In patients on dialysis who undergo pulmonary resection, there is a high incidence of pulmonary complications, in addition to hyperkalemia, hemodynamic instability, and a tendency for postoperative dialysis-associated bleeding.