Jun Atsumi

Video-assisted thoracic lobectomy with bronchoplasty for lung cancer, with special reference to methodology.

Few studies have described video-assisted thoracic surgery (VATS) to bronchoplasty with pulmonary resection. Here, we report the successful implementation of VATS bronchoplasty, as determined retrospectively. Between 2005 and 2010, 362 patients underwent elective lung resection for malignant or benign lung tumors. Of these patients, VATS lobectomy with bronchoplasty was performed in seven patients (four men, three women; median age, 72.9 years). The medical records were retrospectively reviewed. Of the seven patients, six had primary lung cancer (PLC), and one had metastatic cancer of the lung. The surgical procedures were lobectomy with wedge bronchoplasty. The patients with PLC also underwent mediastinal or hilar lymph node dissection. The median total operating time was 230 min, and the median blood loss was 152 ml. The median postoperative hospital stay was seven days, without major postoperative complications. The most important feature of the described method is that the surgeon mainly observes the operative field directly, through a working wound; the surgical team observes via a monitor. An advantage for the surgeon is the ability to use the same instruments in VATS as are used in conventional thoracotomy, as well as the same suturing techniques in vascular reconstruction, especially involving the pulmonary artery.

Establishment of a human lung cancer cell line with high metastatic potential to multiple organs: gene expression associated with metastatic potential in human lung cancer

Convenient and reliable multiple organ metastasis model systems might contribute to understanding the mechanism(s) of metastasis of lung cancer, which may lead to overcoming metastasis and improvement in the treatment outcome of lung cancer. We isolated a highly metastatic subline, PC14HM, from the human pulmonary adenocarcinoma cell line, PC14, using an in vivo selection method. The expression of 34,580 genes was compared between PC14HM and parental PC14 by cDNA microarray analysis. Among the differentially expressed genes, expression of four genes in human lung cancer tissues and adjacent normal lung tissues were compared using real-time reverse transcription polymerase chain reaction. Although BALB/c nude mice inoculated with parental PC14 cells had few metastases, almost all mice inoculated with PC14HM cells developed metastases in multiple organs, including the lung, bone and adrenal gland, the same progression seen in human lung cancer. cDNA microarray analysis revealed that 981 genes were differentially (more than 3-fold) expressed between the two cell lines. Functional classification revealed that many of those genes were associated with cell growth, cell communication, development and transcription. Expression of three upregulated genes (HRB-2, HS3ST3A1 and RAB7) was higher in human cancer tissue compared to normal lung tissue, while expression of EDG1, which was downregulated, was lower in the cancer tissue compared to the normal lung. These results suggest that the newly established PC14HM cell line may provide a mouse model of widespread metastasis of lung cancer. This model system may provide insights into the key genetic determinants of widespread metastasis of lung cancer.

Is epidural analgesia necessary after video-assisted thoracoscopic lobectomy?

Most studies have shown that thoracic epidural analgesia reduces postoperative pain, but it carries potential risks. Recently, video-assisted thoracoscopic surgery has become an established technique that causes minimal postoperative pain. This report shows that thoracic epidural analgesia is not always necessary after video-assisted thoracoscopic lobectomy. From January to December 2007, 30 consecutive patients who underwent video-assisted thoracoscopic lobectomy were examined retrospectively. We analyzed the necessity for routine thoracic epidural analgesia. The continuous subcutaneous analgesia catheter for morphine (2 mg in 48 h) was removed from 15 patients on postoperative day 1, and from the other 15 on day 2. We administered loxoprofen sodium hydrate, diclofenac sodium suppository, pentazocine hydrochloride, and mexiletine hydrochloride for postoperative analgesia, as needed. The mean pain score was no more than 1.0. The maximum score was 3.0 on day 0, and 2.0 on day 14; subsequently, no pain score exceeded 2.0. The postoperative hospital stay was 8.7 ± 0.8 days. All patients made uneventful postoperative recoveries. There is no need for thoracic epidural analgesia after every video-assisted thoracoscopic lobectomy because our patients recovered with no serious complication. Less invasive surgical approaches should require simpler postoperative pain management.

Eprobe-mediated screening system for somatic mutations in the KRAS locus

Activating mutations in the Kirsten rat sarcoma viral oncogene homolog (KRAS) loci are largely predictive of resistance to epidermal growth factor receptor (EGFR) therapy in colorectal cancer (CRC). A highly sensitive detection system for the KRAS gene mutations is urgently needed; however, conventional methods have issues with feasibility and cost performance. Here, we describe a novel detection system using a fluorescence ‘Eprobe’ capable of detecting low level KRAS gene mutations, via real-time PCR, with high sensitivity and simple usability. We designed our Eprobes to be complementary to wild-type (WT) KRAS or to the commonly mutated codons 12 and 13. The WT Eprobe binds strongly to the WT DNA template and suppresses amplification by blocking annealing of the primer during PCR. Eprobe-PCR with WT Eprobe shows high sensitivity (0.05–0.1% of plasmid DNA, 1% of genomic DNA) for the KRAS mutation by enrichment of the mutant type (MT) amplicon. Assay performance was compared to Sanger sequencing using 92 CRC samples. Discrepancies were analyzed by mutation genotyping via Eprobe-PCR with full match Eprobes for 7 prevalent mutations and the next generation sequencing (NGS). Significantly, the Eprobe system had a higher sensitivity for detecting KRAS mutations in CRC patient samples; these mutations could not be identified by Sanger sequencing. Thus, the Eprobe approach provides for highly sensitive and convenient mutation detection and should be useful for diagnostic applications.

Rapid Detection of SNP (c.309T>G) in the MDM2 Gene by the Duplex SmartAmp Method

Background Genetic polymorphisms in the human MDM2 gene are suggested to be a tumor susceptibility marker and a prognostic factor for cancer. It has been reported that a single nucleotide polymorphism (SNP) c.309T>G in the MDM2 gene attenuates the tumor suppressor activity of p53 and accelerates tumor formation in humans. Methodology In this study, to detect the SNP c.309T>G in the MDM2 gene, we have developed a new SNP detection method, named “Duplex SmartAmp,” which enabled us to simultaneously detect both 309T and 309G alleles in one tube. To develop this new method, we introduced new primers i.e., nBP and oBPs, as well as two different fluorescent dyes that separately detect those genetic polymorphisms. Results and Conclusions By the Duplex SmartAmp method, the genetic polymorphisms of the MDM2 gene were detected directly from a small amount of genomic DNA or blood samples. We used 96 genomic DNA and 24 blood samples to validate the Duplex SmartAmp by comparison with results of the conventional PCR-RFLP method; consequently, the Duplex SmartAmp results agreed totally with those of the PCR-RFLP method. Thus, the new SNP detection method is considered useful for detecting the SNP c.309T>G in the MDM2 gene so as to judge cancer susceptibility against some cellular stress in the clinical setting, and also to handle a large number of samples and enable rapid clinical diagnosis.

Highly sensitive detection of a HER2 12-base pair duplicated insertion mutation in lung cancer using the Eprobe-PCR method

Somatic mutation in human epidermal growth factor receptor-related 2 gene (HER2) is one of the driver mutations in lung cancer. HER2 mutations are found in about 2% of lung adenocarcinomas (ADCs). Previous reports have been based mainly on diagnostic screening by Sanger sequencing or next-generation sequencing (NGS); however, these methods are time-consuming and complicated. We developed a rapid, simple, sensitive mutation detection assay for detecting HER2 12 base pair-duplicated insertion mutation based on the Eprobe-mediated PCR method (Eprobe-PCR) and validated the sensitivity of this assay system for clinical diagnostics. We examined 635 tumor samples and analyzed HER2 mutations using the Eprobe-PCR method, NGS, and Sanger sequencing. In a serial dilution study, the Eprobe-PCR was able to detect mutant plasmid DNA when its concentration was reduced to 0.1% by mixing with wild-type DNA. We also confirmed amplification of the mutated plasmid DNA with only 10 copies per reaction. In ADCs, Eprobe-PCR detected the HER2 mutation in 2.02% (9/446), while Sanger sequencing detected it in 1.57% (7/446). Eprobe-PCR was able to detect the mutation in two samples that were undetectable by Sanger sequencing. All non-ADC samples were wild-type. There were no discrepancies between frozen and formalin-fixed paraffin-embedded tissues in the nine samples. HER2 mutations detected by NGS data validated the high sensitivity of the method. Therefore, this new technique can lead to precise molecular-targeted therapies.

An immunoglobulin G4-related disease mimicking postoperative lung cancer recurrence

A postoperative lung cancer patient presented with lymphadenopathy, pleural thickening, and 18F-fluorodeoxyglucose (FDG) uptake on a positron emission tomography–computed tomography (PET–CT) scan. Lung cancer recurrence was initially suspected, but bilateral submandibular masses with 18F-FDG uptake indicated the possibility of a systemic disease, such as Mikulicz’s disease. High serum immunoglobulin G4 (IgG4) and IgG4-positive plasma cell infiltration in the submandibular glands led to the diagnosis of IgG4-related disease. After systemic steroid therapy, 18F-FDG uptake decreased in both the submandibular glands and the suspected recurrent lesions.

Unanticipated troubles in video-assisted thoracic surgery: A proposal for the classification of troubleshooting

Most thoracic surgeons encounter atypical cases or unexpected situations that usually lead them to convert minimally invasive surgery to open thoracotomy. But are there other options besides open surgery? The purpose of this study was to suggest a video‐assisted thoracic surgery (VATS) classification system and present tips for the application of VATS to atypical cases or unexpected situations. We have categorized VATS procedures for atypical cases or unexpected situations into two groups: the modification of techniques/instruments and the creation of additional access incisions.

Impact of the Bim Deletion Polymorphism on Survival Among Patients With Completely Resected Non–Small-Cell Lung Carcinoma

Purpose A deletion polymorphism of the Bim gene has been reported to be a prognostic factor for patients with non–small-cell lung cancer (NSCLC) treated with epidermal growth factor receptor-tyrosine kinase inhibitors in the Asian population. We investigated the impact of the Bim deletion polymorphism on survival among patients with completely resected NSCLC. Patients and Methods The Bim polymorphism was detected by polymerase chain reaction analysis. We measured overall survival (OS) and recurrence-free survival rates in 411 patients and postrecurrence survival (PRS) in 94 patients who experienced recurrence and received additional anticancer therapy. Results The Bim deletion polymorphism was detected in 61 patients (14.8%). OS rates were significantly lower for patients with the Bim deletion polymorphism than for those with the wild-type sequence. On multivariable analysis, the Bim deletion polymorphism was identified as an independent prognostic factor for OS (hazard ratio, 1.98; 95% CI, 1.17 to 3.36; P = .011). Among the 94 patients who experienced recurrence and were treated with anticancer therapy, patients with the Bim deletion polymorphism showed significantly poorer PRS than those with the wild-type sequence (median, 9.8 months v 26.9 months, respectively; P < .001). Multivariable analysis revealed that the Bim deletion polymorphism was an independent predictor of PRS (hazard ratio, 3.36; 95% CI, 1.75 to 6.47; P < .001). This trend remained apparent in subgroup analyses stratified by EGFR status, histology, and therapeutic modality. Conclusion The Bim deletion polymorphism is a novel indicator of shortened PRS among patients with recurrent NSCLC treated with anticancer therapy in the Asian population.

Pulmonary Large Cell Carcinoma Mimicking an Infected Thoracoabdominal Aortic Aneurysm

Tetsuhiro Nakano, MD, PhD, Kimihiro Shimizu, MD, PhD, Toru Takahashi, MD, PhD,Jun Mohara, MD, PhD, Norimasa Koike, MD, PhD, Osamu Kawashima, MD, PhD,Mitsuhiro Kamiyoshihara, MD, PhD, Masayuki Sugano, MD, Takashi Ibe, MD, PhD,Seiichi Kakegawa, MD, Toshiteru Nagashima, MD, Jun Atsumi, MD, and Izumi Takeyoshi, MD, PhD