Multimodal imaging using optical coherence tomography and endolaryngeal ultrasonography in a new rabbit VX2 laryngeal cancer model.

BACKGROUND AND OBJECTIVE: Optical coherence tomography (OCT) provides ultrahigh-resolution imaging of tissues within a depth of a few millimeters, whereas ultrasonography provides good imaging further below the surface. We aimed to develop a minimally invasive rabbit model of VX2 laryngeal cancer, suitable for these two imaging modalities through a transoral approach. We also sought to study the utility of combined OCT and endolaryngeal ultrasonography (EUS) for evaluation of early and advanced laryngeal cancer, using this model. MATERIALS AND METHODS: VX2 tumor suspension was inoculated into the vocal folds of ten rabbits by injection through the trans-thyrohyoid membrane. The tumor model was characterized by rigid laryngoscopy and the tumor generation rate was 80% (8/10). Correlation between frequency-domain OCT and high-frequency EUS were used to visualize laryngeal tumors in the area of protruding mass formation in four rabbits, one week after injection (group A) and the remaining four rabbits two weeks after injection (group B). RESULTS: A small submucosal tumor was observed with rigid laryngoscopy in group A, and pathologic evaluation showed that the tumor was close to the basement membrane of the vocal fold mucosa, but had not invaded. OCT confirmed that the lining of the mucosa and basement membrane of the vocal fold was not broken, but the mucosa had thinned at the most elevated ridge. However, these lesions were not detected by EUS, and the overall shape of the tumor could not be clearly identified by EUS. A large tumor filling the laryngeal lumen was observed with rigid laryngoscopy in group B, and nearly the entire vocal fold, including the paraglottic space, was found to be involved on pathologic analysis. Distinguishing between normal structures and tumor was difficult using OCT; however, EUS confirmed the overall shape, size, and extent of the tumor, and the paraglottic space and thyroid cartilage were shown to be intact. CONCLUSIONS: This study is the first experimental trial, assessing the value of multimodal imaging using OCT and EUS in a rabbit VX2 laryngeal tumor model. Combining OCT and EUS helped to identify changes in laryngeal mucous membranes, and could potentially be used to identify laryngeal tumors and predict how tumors progress. This combined modality could help in determining tumor extent, assisting in diagnosis, and establishing a treatment plan for laryngeal cancer.

Optical imaging of subacute airway remodeling and adipose stem cell engraftment after airway injury.

Acquired airway injury is frequently caused by endotracheal intubations, long-term tracheostomies, trauma, airway burns, and some systemic diseases. An effective and less invasive technique for both the early assessment and the early interventional treatment of acquired airway stenosis is therefore needed. Optical coherence tomography (OCT) has been proposed to have unique potential for early monitoring from the proliferative epithelium to the cartilage in acute airway injury. Additionally, stem cell therapy using adipose stem cells is being investigated as an option for early interventional treatment in airway and lung injury. Over the past decade, it has become possible to monitor the level of injury using OCT and to track the engraftment of stem cells using stem cell imaging in regenerative tissue. The purpose of this study was to assess the engraftment of exogenous adipose stem cells in injured tracheal epithelium with fluorescent microscopy and to detect and monitor the degree of airway injury in the same tracheal epithelium with OCT. OCT detected thickening of both the epithelium and basement membrane after tracheal scraping. The engraftment of adipose stem cells was successfully detected by fluorescent staining in the regenerative epithelium of injured tracheas. OCT has the potential to be a high-resolution imaging modality capable of detecting airway injury in combination with stem cell imaging in the same tracheal mucosa.

Gefitinib in Selected Patients with Pre-Treated Non-Small-Cell Lung Cancer: Results from a Phase IV, Multicenter, Non-Randomized Study (SELINE).

BACKGROUND: This study was designed to analyze the efficacy of gefitinib as a second-line therapy, according to the clinical characteristics in Korean patients with non-small-cell lung cancer (NSCLC). METHODS: In this Phase IV observational study, we recruited patients, previously failed first-line chemotherapy, who had locally advanced or metastatic NSCLC, and who were found to be either epidermal growth factor receptor (EGFR) mutation-positive or satisfied 2 or more of the 3 characteristics: adenocarcinoma, female, and non-smoker. These patients were administered with gefitinib 250 mg/day, orally. The primary endpoints were to evaluate the objective response rate (ORR) and to determine the relationship of ORRs, depending on each patient's characteristics of modified intent-to-treat population. RESULTS: A total of 138 patients participated in this study. One subject achieved complete response, and 42 subjects achieved partial response (ORR, 31.2%). The subgroup analysis demonstrated that the ORR was significantly higher in patients with EGFR mutation-positive, compared to that of EGFR mutation-negative (45.8% vs. 14.0%, p=0.0004). In a secondary efficacy variable, the median progression-free survival (PFS) was 5.7 months (95% confidence interval, 3.9~8.4 months) and the 6-month PFS and overall survival were 49.6% and 87.9%, respectively. The most common reported adverse events were rash (34.4%), diarrhea (26.6%), pruritus (17.5%), and cough (15.6%). CONCLUSION: Gefitinib was observed in anti-tumor activity with favorable tolerability profile as a second-line therapy in these selected patients. When looking at EGFR mutation status, EGFR mutation-positive showed strong association with gefitinib by greater response and prolonged PFS, compared with that of EGFR mutation-negative.

A case of pneumothorax treated with thoracoscopic pleurodesis.

A 75 year-old male patient presented with exertional dyspnea that he had suffered for 7 days. The chest X-ray showed right-sided pneumothorax. Closed thoracostomy was performed on the 1st day of hospitalization and repeated with talc sclerotherapy and lower-power suction, but neither could improve air-leakage. On the 14th day of hospitalization, thoracoscopy via pleurodesis was performed and the pneumothorax resolved. We report here on a rare case of intractable pneumothorax treated by thoracoscopic pleurodesis with talc.

Lung cancer patients who are asymptomatic at diagnosis show favorable prognosis: a korean Lung Cancer Registry Study.

PURPOSE AND METHODS: The outcomes of lung cancer patients who were asymptomatic at diagnosis have never been reported as part of a large-scale study. A national survey of lung cancer in South Korea registered a total of 8788 patients diagnosed in 2005. We report the results herein, with an emphasis on the prognosis of the asymptomatic lung cancer patients. RESULTS: Adenocarcinoma was the most frequent (36.1%) histopathologic type, followed by squamous cell carcinoma (32.1%), large cell carcinoma (1.5%), and small cell carcinoma (13.5%). In most cases, lung cancer was detected with subjective symptoms, but 6.5% of cases had no symptoms indicative of lung cancer at the time of diagnosis. Compared to symptomatic patients, asymptomatic patients were younger, more often female, non-smokers, and more frequently presented with adenocarcinoma. Initial treatments were surgery (22.1%), radiation therapy (7.8%), chemo-radiation therapy (5.4%), and chemotherapy (38%), while 26.6% of patients were recorded to have supportive care only. Asymptomatic patients received surgery in 60.0% of cases, and they showed significantly longer survival times than symptomatic patients. Absence of symptoms at diagnosis significantly reduced the risk of death from non-small cell lung cancer, regardless of patient age, patient gender, stage at diagnosis, smoking history, or whether treatment was performed, but did not reduce the risk of death from small cell lung cancer. CONCLUSIONS: Adenocarcinoma has grown to be the leading histopathologic type of lung cancer in South Korea. Absence of symptom at diagnosis is a favorable prognostic factor for patients with non-small cell lung cancer.