Kazutoshi Hamanaka

Intraoperative ultrasonographic localization of pulmonary ground-glass opacities

OBJECTIVES Ground-glass opacities are typically difficult to inspect and to palpate during video-assisted thoracic surgery. We therefore examined whether ultrasonographic assessments could localize ground-glass opacities and help to achieve adequate resection margins. METHODS An intraoperative ultrasonographic procedure was prospectively performed on 44 patients harboring ground-glass opacities of less than 20 mm in diameter to localize these lesions and to achieve adequate margins. We also examined whether there were any complications resulting from the intraoperative ultrasonogram, such as lung injury, heart injury, or arrhythmia. We excluded patients with both asthma and chronic obstructive pulmonary disease from this study inasmuch as the intraoperative ultrasonographic procedure is more difficult to interpret when residual air is present in the lung. RESULTS A total of 53 ground-glass opacities were successfully identified by intraoperative ultrasonography without any complications. Of the 20 mixed ground-glass opacities that we examined, 15 were found on palpation. However, only 4 (12.1%) of the 33 pure ground-glass opacities could be palpated. In all instances in which complete collapse of the lung was achieved (30/53 of these cases), high-quality echo images were obtained. Additionally, a strong correlation was found between the resection margins measured by ultrasonogram and the margins determined by histologic examination in the resected lung specimens (r(2) = 0.954, P < .001). CONCLUSIONS Intraoperative ultrasonography can both safely and effectively localize pulmonary ground-glass opacities in a completely deflated lung. This procedure is also useful for the evaluation of surgical margins in a resected lung. Hence, ultrasonography may assist surgeons to perform minimally invasive lung resections with clear surgical margins during the treatment of solitary lung ground-glass opacity.

Computed tomography attenuation predicts the growth of pure ground-glass nodules.

OBJECTIVES Cases of lung cancer with pure ground-glass nodules (GGNs) have been detected with increasing frequency since the advent of computed tomography (CT), and growth is sometimes noted during follow-up. The objective of this study was to evaluate the potential predictive factors for pure GGN growth. MATERIALS AND METHODS We retrospectively examined 124 cases involving pure GGNs. Patients were monitored for > 2 years using high-resolution CT. After a median follow-up period of 57.0 months, GGNs showed growth in 64 of the 124 cases. We compared the patient characteristics and tumor properties of cases with and without growth. The predictive value of the mean CT attenuation for GGN growth was evaluated using receiver operating characteristic curve analysis. RESULTS Univariate analysis revealed significant differences between mean CT attenuation values in patients with and without growth (-602.9 ± 90.7 Hounsfield units [HU] vs -705.7 ± 77.7HU, P < 0.0001). The final incidence of growth was estimated to be significantly higher for lesions with a mean CT attenuation value of ≥ -670HU (n = 62; 93.2%) than for lesions with values of < -670HU (n = 62; 31.6%; P < 0.0001). The sensitivity and specificity for predicting tumor growth using this cutoff value were 78.1% and 80.0%, respectively (area under the curve, 0.81). CONCLUSION The mean CT attenuation value could be useful in predicting the growth of GGNs.

Usefulness of vessel-sealing devices for ≤7 mm diameter vessels: a randomized controlled trial for human thoracoscopic lobectomy in primary lung cancer

OBJECTIVES Vessel-sealing devices (VSDs) are widely used for various surgical procedures, including thoracoscopic surgery, but very few reports have compared their safety and usefulness with human thoracoscopic lobectomy procedures not employing VSDs. METHODS Primary lung cancer patients for whom a thoracoscopic lobectomy involving mediastinal lymph node dissection was planned in our department from April 2011 to March 2013 were recruited for the study. Patients were randomly allocated to a control group (n = 14) or a VSD group (n = 44), which comprised three sub-groups, namely EnSeal (n = 17), LigaSure (n = 15) and Harmonic (n = 12). The control group comprised patients undergoing surgery solely with ligation and conventional electrocautery. EnSeal, LigaSure and Harmonic were chosen because they are the three most popular disposable VSDs used in Japan. In the VSD groups, the proximal side of pulmonary artery stumps (≤7 mm diameter) were ligated and then treated with respective devices. Primary end-points were burst pressure of the pulmonary artery stump (measured using resected specimens), operative time, intraoperative blood loss, instances of endostapler use, intraoperative surgeon stress (assessed by visual analogue scale) and postoperative drainage volume and duration. As a secondary objective, the individual VSD groups were also compared with each other. RESULTS The burst pressure of ligation-treated pulmonary artery stumps was higher than that of VSD-treated stumps (P <0.0001). The burst pressure of <5-mm-wide VSD-treated stumps was higher than that of ≥5-mm-wide stumps (P = 0.0421). However, the burst pressure for all groups and all vessel diameters was sufficient to withstand the physiological pulmonary artery pressure. The VSD group demonstrated reduced intraoperative blood loss (P = 0.0241), surgeon stress (P = 0.0002), postoperative drainage volume (P = 0.0358) and shortened postoperative drainage duration (P = 0.0449). Operative time and the instances of endostapler use did not significantly differ. Comparison between each of the VSD groups revealed no significant differences. None of the patients experienced serious perioperative complications or died because of surgery. CONCLUSION VSD is simple and safe to use in thoracoscopic lobectomy involving mediastinal lymph node dissection for primary lung cancer. Furthermore, none of the VSDs used in this study presented any observable differences in quality that could lead to clinical problems.

Clinical features of lung cancer in smokers with light and mild chronic obstructive pulmonary disease: a retrospective analysis of Japanese surgical cases.

OBJECTIVES We estimated the influence of chronic obstructive pulmonary disease (COPD) upon the clinicopathological characteristics of lung cancer (LC) in Japanese surgical cases by comparing LC cases in non-COPD smokers. METHOD A consecutive cohort comprising 157 COPD patients (78 in Global Initiative for Obstructive Lung Disease-1 (GOLD-1) and 79 in GOLD-2) and 374 non-COPD smoker-LC patients were enrolled in this study. Comparative analyses of the clinicopathological features of these two groups, including clinical outcomes, were performed. RESULTS By analyzing all cases, we found that LC patients with COPD were older on average, more likely to be male, and heavier smokers than LC patients without COPD. In sub-analysis involving matched patient backgrounds, histological differentiation grade of LC in smokers with COPD was lower than in LC smokers without COPD, although distribution of clinical stages and histological types of LCs did not differ between smokers with and without COPD. The 5-year-survival rate in COPD patients was poorer than in non-COPD smokers in terms of both overall (38% vs 54%) and cancer-related mortality (45% vs 63%). By single-variant risk analysis, COPD became a prognostic factor. CONCLUSION We concluded from our analysis that COPD-related LC may have a higher malignant potential than LC in non-COPD smokers, as the histological differentiation grade and clinical outcomes were poorer.

Pulmonary Nodules: Preliminary Experience with Semiautomated Volumetric Evaluation by CT Stratum

RATIONALE AND OBJECTIVES To evaluate the performance of custom-made software designed to quantify volume and weight of focal portions of lung tumors in regions of interest (ROI) and volume of interest on thin-section computed tomography (CT) images by stratum of CT values. METHODS AND MATERIALS Volume and weight of lung portions were measured three-dimensionally and semiautomatically by CT stratum and compared with standard manual measurements. One each of a partly solid tumor (including initial and follow-up high-resolution CT scans), partly solid tumor with most parts showing solid density, and nonsolid tumors in the mid-zone of the lung were analyzed. The doubling time (DT) of tumor volume and mass were calculated by stratum of CT values. RESULTS The software-measured tumor weight in lung periphery was reproducible, with and without trimming of intervening lung structures between borders of ROIs and tumor. For the lesion in the midlung zone, the fairly thick nearby pulmonary vessels degraded the measurements, with a higher measurement error, indicating the need to trim these structures off the ROI. Software measurements allowed quantification of tumor progress based on increase in tumor mass, without significant increase in tumor volume. The DTs for both tumor volume and mass were different among the four strata of CT values in the partly solid nodule. CONCLUSION Our semiautomated volumetric method involving measurement by CT stratum is promising for evaluation of lung tumor progress and aggressiveness.

Multiple Schwannomas of the Bilateral Mediastinal Vagus Nerves

Multiple schwannomas arising from the mediastinal vagus nerve are very rare, but herein we report a case with such lesions involving the bilateral intrathoracic vagus nerves. A 43-year-old man presented with multiple mediastinal tumors during a check-up. A chest computed tomographic scan revealed multiple lesions that appeared strung together like beads along the right vagus nerve. Three small tumors were also evident on the left side of the esophagus. We performed a complete resection of the bilateral mediastinal tumors through right thoracoscopic surgery. The pathologic diagnosis for each of these tumors was a schwannoma without malignant components.

Benefits of video-assisted thoracic surgery for repeated pulmonary metastasectomy

PurposeThe use of repeated pulmonary resection for metachronous pulmonary metastasis has increased. We assessed whether video-assisted thoracic surgery (VATS) produced greater benefits than classic thoracotomy for repeated pulmonary metastasectomy procedures.MethodsA total of 46 patients who had undergone two or more pulmonary metastasectomies from 1995 to 2008 were analyzed in this study. These patients were classified into four groups as follows: group A (previous VATS/present VATS); group B (previous VATS/present thoracotomy); group C (previous thoracotomy/present VATS); group D (previous thoracotomy/present thoracotomy). The clinical features of these four groups were then compared.ResultsThe operating time and the duration of thoracic drainage were longer in group D than in group A or B. The operating time was also longer in group C than in group A. Intraoperative bleeding was greater in group D patients than in other three groups. There were no discernible morbidities resulting from VATS in groups A or C. No differences were found in the occurrence of relapse among the groups. The mean interval from the previous to the present pulmonary metastasectomy also did not differ significantly among groups.ConclusionVATS can result in a shortened operating time, reduced intraoperative bleeding, and generally fewer complications compared with repeated classic thoracotomy. VATS is also potentially a curative procedure as it is not inferior to classic thoracotomy in terms of the relapse rate after repeated pulmonary metastasectomy.

Co-occurrence of mucoepidermoid carcinoma and squamous cell carcinoma of the esophagus: Report of a case

A case of co-occurrence of a mucoepidermoid carcinoma (MEC) and a squamous cell carcinoma (SCC) in the esophagus is described. The present patient was a 61-year-old man who underwent a curative esophagectomy with a regional lymph node dissection for a MEC in the lower esophagus and a SCC near the esophagogastric junction. The two lesions were endoscopically and histologically divided by a normal esophageal mucosa. The MEC of the esophagus consisted of SCC cells and signet-ring cells, and a mucin product and carcinoembryonic antigen, which were found at high levels in the blood serum before surgery, were detected histochemically in the signet-ring cells. The follow-up survey of the patients with esophageal MEC previously reported in Japan showed that most of the patients died of either local recurrence or widespread metastasis after treatment; the overall 5-year survival rate was 24.4% in the total 25 cases, and 27.7% in the 22 resected cases. However, 6 patients who died of therapeutic complications were included among these patients; furthermore, the 5-year survival rate after surgery was 29.2% in the patients treated over the last decade (1989–1998). We expect that the clinical outcome of patients treated for esophageal MEC will therefore improve in the future.

Colchicine as an effective treatment for postpericardiotomy syndrome following a lung lobectomy

Postpericardiotomy syndrome (PPS) is a frequent complication of various cardiac procedures that involve entry into the pericardium, but rarely occurs after pulmonary surgery because the pericardium is usually preserved during this procedure. The standard treatment for PPS is the administration of non-steroidal anti-inflammatory drugs (NSAIDs). Recent studies have indicated however, that colchicine may be useful for the treatment and prevention of this syndrome. Here, we describe the successful use of colchicine to treat PPS in a lung cancer patient who developed this complication following a lung lobectomy. A 64-year-old woman with a stage IA lung tumor underwent a left upper lobectomy with a mediastinal lymph node dissection. Severe precordial pain occurred 10 days after surgery, and accumulations of pericardial and pleural fluid were revealed by chest X-ray, echocardiogram, and chest computed tomography. These symptoms were not alleviated by antibiotics, thoracic cavity drainage, or NSAIDs. However, the administration of colchicine (initial dose of 1.0 mg and maintenance dose of 0.5 mg daily for three months) in combination with NSAIDs resolved these symptoms immediately after the first dosage. In addition, the patient remains free of any recurrent pericarditis at six months after this episode.

Occurrence of a Simultaneous Bilateral Spontaneous Pneumothorax Due to a Pleuro-Pleural Communication

Herein we present a case of a simultaneous bilateral spontaneous pneumothorax caused by a pleuro-pleural communication. A 70-year-old man with a history of esophagectomy presented with dyspnea. A chest roentgenogram revealed a bilateral pneumothorax and bilateral chest drainage procedures were performed. A left bullectomy was also performed 3 days later due to persistent air leakage on the left side. During surgery, a small fistula was detected in the anterior mediastinal pleura and was found to be in communication with the bilateral pleural spaces.