PubMed Health⌕ Search

Biomedical subjects

Noriaki Kurimoto

Publications and source records attributed to Noriaki Kurimoto.

11 recordsLinked to original sources

Telomerase expression in noncancerous bronchial epithelia is a possible marker of early development of lung cancer.

Centrally located lung cancers in smokers frequently associated with subsequent primary tumors. We evaluated the telomerase expression chronologically in noncancerous epithelia as a risk factor of susceptibility to lung cancer development. Telomerase protein expression was examined in situ by immunohistochemistry in 26 noncancerous bronchial epithelia adjacent to centrally located early-stage lung cancers in sequential 23 patients treated by photodynamic therapy or surgery among 206 patients who underwent autofluorescence bronchoscopy from 1997 to 2003. Among the 15 lesions in 12 patients treated by photodynamic therapy alone, 11 lesions achieved complete remission after photodynamic therapy, and none of their noncancerous bronchial epithelia was telomerase positive. On the contrary, in the remaining four lesions, either recurrence or secondary lung cancer developed adjacent to the successfully treated primary cancer within 26 months, and the telomerase protein expression in noncancerous epithelia was detected before the secondary cancer development (P < 0.001). The overall relationship of human telomerase reverse transcriptase positivity in noncancerous epithelia and subsequent lung cancer development, including patients treated by radiation or surgery, showed higher significance (P < 0.0001). Histologically "normal" bronchial epithelia in smokers may unphysiologically express telomerase as a field, and such epithelia are likely susceptible to develop lung cancer. We propose that ectopic expression of telomerase in bronchial epithelia may precede transformation in human lung cancer development and that detection of telomerase protein in noncancerous bronchial epithelia will become a useful marker detecting high-risk patients for lung cancer development.

Biomarkers, Tumor↗

Mucinous (colloid) adenocarcinoma.

We describe a case of primary mucinous (colloid) adenocarcinoma of the lung. The patient was a 61-year-old male with a peripheral mass of the left lung. Retrospectively, the mass, which showed slow growth later, could be seen in a chest X-ray 3 years before surgery. The tumor was filled with a gelatinous substance resembling strawberry jelly, macroscopically. Microscopically, it was mucin with a small amount of malignant cells (adenocarcinoma). Diagnosis was mucinous (colloid) adenocarcinoma, which is a very rare intrapulmonary neoplasm. Mucinous (colloid) adenocarcinoma is suspected when a gelatinous substance like strawberry jelly is observed intraoperatively in the lung.

Adenocarcinoma, Mucinous↗

Endobronchial ultrasonography guidance for transbronchial needle aspiration using a double-channel bronchoscope.

STUDY OBJECTIVES: Endobronchial ultrasonography (EBUS) is used as guidance for transbronchial needle aspiration (TBNA), and real-time imaging of the needle position cannot be confirmed with a single-channel bronchoscope. We assessed the usefulness of EBUS-guided TBNA using a double-channel bronchoscope (EBUS-D), which provides real-time needle position, and compared it with EBUS-guided TBNA using a single-channel bronchoscope (EBUS-S). DESIGN: Randomized, comparative prospective study. SETTING: Hiroshima City Hospital, a tertiary-referral teaching hospital. PATIENTS: Between January 2000 and August 2003, 55 patients with intrathoracic lymphadenopathy were included. Patients were randomized to undergo EBUS-D (n = 30) or EBUS-S (n = 25). METHODS: EBUS-D: The EBUS probe and TBNA catheter were inserted simultaneously through a double-channel bronchoscope. Once the needle placement in the lesion was confirmed by EBUS, TBNA was performed. EBUS-S: The EBUS probe was removed after the determination of the penetration site. Then, the TBNA catheter was inserted and TBNA was performed. RESULTS: All the lymph nodes could be visualized with EBUS in each group of patients. In the EBUS-D group, the TBNA needle was visualized as a hyperechoic point on the real-time EBUS image. The diagnostic accuracy rate of EBUS-D and EBUS-S were statistically significantly different (97% vs 76%, respectively; p = 0.025). On second attempt of TBNA, the diagnostic rate of the EBUS-D group was superior to that of the EBUS-S group (85.7% vs 33.3%, respectively; p = 0.036). The mean number of penetrations was 1.24 in the EBUS-D group and 1.36 in the EBUS-S group. No complications were observed in the EBUS-D group, but a self-limiting hemorrhage occurred in a patient in the EBUS-S group. CONCLUSION: EBUS-D is useful for diagnosing intrathoracic lymphadenopathy, and the obtained specimen with real-time confirmation of the needle is directly proportional to an accurate diagnosis.

Aged↗

Stenting at the flow-limiting segment in tracheobronchial stenosis due to lung cancer.

Airway stenting at the wave-speed flow-limiting segment (the choke point) is assessed. We determined prospectively the precise location of the choke point using the flow-volume curve, endobronchial ultrasonography, ultrathin bronchoscopy, and three-dimensional computed tomography scan before and after stenting in 64 patients with extrincic compression due to lung cancer. We noted distinct flow-volume curve patterns specific to the type of stenosis. The tracheal stenosis group indicated fixed narrowing patterns with an expiratory plateau, bronchial stenosis group dynamic collapse patterns with an expiratory flow deterioration (choking), carinal stenosis group combined fixed and dynamic patterns, and extensive stenosis group complex patterns containing elements of all the former. After stenting, almost full-function patterns with significant improvement in PEF were observed in all groups (p < 0.01, p < 0.05, p < 0.001, p < 0.01, respectively). In patients with extensive stenosis, implantation of additional stents was required when the choke points were observed to have migrated to the areas of malacia with cartilage destruction by the tumor. Secondary stenting at migrated choke points resulted in a significant improvement in PEF over the initial stenting (p < 0.01). Stenting at the choke point improved expiratory flow limitation by increasing the cross-sectional area, supporting the weakened airway wall and relieving dyspnea.

Adult↗

Endobronchial ultrasonography.

Endobronchial ultrasonography (EBUS) allows visualization of the tracheobronchial tree with real-time ultrasound and permits visualization of the internal structure of pulmonary lesions, which may narrow the differential diagnosis. The indications for EBUS are to (1) determine the depth of tumor invasion of tracheobronchial lesions, (2) define positional relationships with the pulmonary artery and veins and hilar structures and determine the extent of tumor invasion, (3) visualize paratracheal and peribronchial lymph nodes and metastatic lesions and enable EBUS-guided transbronchial needle aspiration (TBNA), and (4) localize and diagnose peripheral pulmonary lesions (benign or malignant). New and evolving applications of EBUS will increase the cost-effectiveness of EBUS in the diagnosis and treatment of thoracic diseases.

Journal Article↗

Endobronchial ultrasonography using a guide sheath increases the ability to diagnose peripheral pulmonary lesions endoscopically.

STUDY OBJECTIVE: To assess the ability of endobronchial ultrasonography (EBUS) using a guide sheath (EBUS-GS) to diagnose peripheral pulmonary lesions. METHOD: We devised a technique for EBUS-GS covering a miniature probe, and 150 lesions were evaluated in a prospective open study. In this procedure, the probe covered by a guide sheath is introduced into the lesion via the working channel of a bronchoscope. The probe is withdrawn, while the guide sheath is left in situ. A brush or biopsy forceps is introduced through the guide sheath into the lesion. RESULTS: One hundred sixteen of 150 EBUS-GS procedures (77%) were diagnostic. Cases in which the probe was located within the lesion had a significantly higher diagnostic yield (105 of 121 cases, 87%) than when the probe was located adjacent to it (8 of 19 cases, 42%) [p < 0.0001, chi(2)]. The diagnostic yield from EBUS-GS in lesions </= 10 mm (16 of 21 lesions, 76%), >10 to </= 15 mm (19 of 25 lesions, 76%; p = 0.99, chi(2)), >15 to </= 20 mm (23 of 35 lesions, 66%; p = 0.41, chi(2)), and > 20 to </= 30 mm (33 of 43 lesions, 77%; p = 0.96, chi(2)) were similar, demonstrating the efficacy of EBUS-GS even in lesions </= 10 mm in diameter. In 54 of 81 lesions </= 20 mm, fluoroscopy was not able to confirm whether the forceps reached the lesion. However, the yield was the same with (67%, 18 of 27 lesions) and without (74%, 40 of 54 lesions) successful fluoroscopy (p = 0.96, chi(2)). Moderate bleeding occurred in two patients (1%); there were no other complications. CONCLUSIONS: EBUS-GS is a useful method for collecting samples from peripheral pulmonary lesions, even those too small to be visualized under fluoroscopy.

Aged↗

Interventional bronchoscopy in the management of airway stenosis due to tracheobronchial tuberculosis.

STUDY OBJECTIVES: To assess the efficacy and complications of interventional bronchoscopic techniques in treating airway stenosis due to tracheobronchial tuberculosis. DESIGN: Case series. SETTING: Respiratory care centers at two tertiary care referral teaching hospitals in Japan, Hiroshima City Hospital and Okayama Red Cross Hospital. PATIENTS AND INTERVENTIONS: A total of 30 patients were admitted to the hospital with a diagnosis of tracheobronchial tuberculosis between January 1991 and January 2002. Of those 11 patients received interventional bronchoscopy, including stent placement, laser photoresection, argon plasma coagulation (APC), balloon dilatation, cryotherapy, and endobronchial ultrasonography (EBUS). One patient with complete bronchial obstruction underwent a left pneumonectomy. RESULTS: Six patients underwent stent placement after balloon dilatation, while the remaining five patients underwent only balloon dilatation. In six patients, Dumon stents were successfully placed to reestablish the patency of the central airways. Two patients first had Ultraflex stents implanted but had problems with granulation tissue formation and stent deterioration caused by metal fatigue due to chronic coughing. Dumon stents then were placed within the Ultraflex stents after the patient had received treatment with APC and mechanical reaming using the bevel of a rigid bronchoscope. In four patients, EBUS images demonstrated the destruction of bronchial cartilage or the thickening of the bronchial wall. The main complications of Dumon stents are migration and granulation tissue formation, necessitating stent removal, or replacement, and the application of cryotherapy to the granuloma at the edge of the stent. CONCLUSION: Interventional bronchoscopy should be considered feasible for management of tuberculous tracheobronchial stenosis. Dumon stents seem to be appropriate, since removal or replacement is always possible. Ultraflex stents should not be used in these circumstances because removal is difficult and their long-term safety is uncertain. EBUS could provide useful information in evaluating the condition of the airway wall in cases of tracheobronchial tuberculosis with potential for bronchoscopic intervention.

Bronchi↗

Endobronchial ultrasonography in the diagnosis and treatment of relapsing polychondritis with tracheobronchial malacia.

Relapsing polychondritis (RP) with tracheobronchial involvement has a poor prognosis, and a delay in diagnosis increases morbidity and mortality; however, the diagnosis is difficult to make. Endobronchial ultrasonography (EBUS) revealed changes in the tracheobronchial cartilage in two patients who met the criteria for RP, and facilitated the diagnosis. In these cases, EBUS revealed a poorly defined bronchial wall structure with two patterns of cartilaginous damage: fragmentation and edema. These cases were successfully treated by the implantation of nitinol stents, the sizes of which were determined by EBUS. EBUS was found to be useful in the diagnosis and treatment of RP.

Aged↗

Endobronchial ultrasonography in the assessment of centrally located early-stage lung cancer before photodynamic therapy.

To evaluate the utility of endobronchial ultrasonography (EBUS) in selecting appropriate candidates with centrally located early-stage lung cancer for photodynamic therapy (PDT) with curative intent, we performed EBUS before PDT in 18 biopsy-proven squamous cell carcinomas (including three carcinoma in situ) that had been considered to be appropriate candidates for PDT by conventional bronchoscopy and high-resolution computed tomography (HR-CT). Nine lesions were diagnosed as intracartilaginous by EBUS and subsequently PDT was performed. Long-term complete remission has been achieved in these patients with a median follow-up term after PDT of 32 months. The remaining nine lesions were diagnosed as extracartilaginous by EBUS and were considered candidates for other therapies such as surgical resection, chemotherapy, and radiotherapy, although two were invisible by HR-CT, three were superficial, and five were < or = 1 cm in diameter on observation by bronchoscopy. The depth of tumor invasion estimated by EBUS was proven to be accurate by histopathologic findings in six specimens after surgical resection. We conclude that EBUS is a useful technique that might be considered in addition to conventional bronchoscopy and HR-CT to improve the efficacy of PDT in patients with centrally located early-stage lung cancer.

Aged↗

Analysis of the internal structure of peripheral pulmonary lesions using endobronchial ultrasonography.

STUDY OBJECTIVE: To correlate the internal structure of peripheral pulmonary lesions, as visualized by endobronchial ultrasonography (EBUS), and the histology of the surgical specimen to develop a classification system for distinguishing benign from malignant lesions by EBUS. DESIGN: Retrospective review. SETTING: A national hospital. PATIENTS: One hundred twenty-four patients with peripheral pulmonary lesions who had undergone EBUS in whom a definitive histologic diagnosis was made. In 69 patients, EBUS findings were correlated with the histology of a surgical specimen. INTERVENTION: EBUS was performed by a miniature probe (20-MHz) introduced up to the lesion through a channel in a bronchoscope. RESULTS: Three classes and six subclasses of lesions were identified by EBUS based on the internal structure of the lesion, focusing on internal echoes, vascular and bronchial patency, and the morphology of the hyperechoic areas, reflecting air in the alveoli and bronchioles. The classes of lesions are as follows: type I, homogeneous pattern (type Ia, with patent vessels and patent bronchioles; type Ib, without vessels and bronchioles); type II, hyperechoic dots and linear arcs pattern (type IIa, without vessels; type IIb, with patent vessels); and type III, heterogeneous pattern (type IIIa, with hyperechoic dots and short lines; type IIIb, without hyperechoic dots and short lines). Twenty-three of 25 type I lesions (92.0%) were benign, while 98 of 99 type II and III lesions (99.0%) were malignant. Twenty-one of 24 type II lesions (87.5%) were well-differentiated adenocarcinomas, and all type IIIb lesions were malignant, including 18 poorly differentiated adenocarcinomas (81.8%). CONCLUSIONS: EBUS permits the visualization of the internal structure of peripheral pulmonary lesions, and this information suggests the histology of the lesion.

Adenocarcinoma↗