[A Case of Colostomy-Free and Long-Term Survival with 5-FU/CDDP for Local Recurrence of Anal Cancer after Chemoradiation Therapy].

We report a case of colostomy-free, long-term survival following 5-FU/CDDP for the local recurrence of anal cancer after chemoradiation therapy(CRT). The patient was a 48-year-old woman who was diagnosed with cStage ⅢA anal cancer. She was treated with CRT(5-FU/MMC plus 59 Gy)and achieved a complete response upon treatment completion. A local recurrence was detected on the left-side wall of her rectum after 6 months. We recommended abdominoperineal resection but the patient refused operation. The patient was treated with chemotherapy consisting of 5-FU(1,000mg/m / 2/day)on days 1-5 and CDDP(100mg/m / 2/day)on day 2. Grade 3 peripheral neuropathy appeared following the completion of 5 courses. Therefore, the dose was reduced to 60%. Twenty-five courses of this treatment were continued and chemotherapy was completed. The patient has been alive with no sign of recurrence for 6 years and 8 months from the initial treatment. CRT for anal cancer is becoming a standard therapy but local recurrence is possible. In these cases, abdominoperineal resection is required. Chemotherapy with 5-FU/CDDP in cases of recurrence can be a colostomy-free option.

[A Case of Resected Pancreatic Metastasis of Rectal Cancer after Multiple Resections of Metastatic Lesions].

A 71-year-old man underwent low anterior resection for rectal cancer 10 years prior. He underwent resection of liver metastasis once and that of lung metastases multiple times after the primary surgery. Computed tomography revealed a mass measuring 22mm in size in the pancreatic body 10 years after the rectal resection. We inspected it before surgery by performing EUS-FNA. On suspicion of metastasis of rectal cancer or primary pancreatic cancer, we performed distal pancreatectomy. The pancreatic tumor was diagnosed as metastasis of the rectal cancer. There were multiple metastases in the resected specimen that we were unable to indicate at the preoperative inspection. Resectable pancreatic metastasis from colorectal cancer is rare, but some patients with long-term survival have been reported. If a patient is tolerant to pancreatectomy and has no metastasis in other organs, the patient should be considered as a good candidate for pancreatectomy.

Autoantigen-specific interactions with CD4+ thymocytes control mature medullary thymic epithelial cell cellularity.

Medullary thymic epithelial cells (mTECs) are specialized for inducing central immunological tolerance to self-antigens. To accomplish this, mTECs must adopt a mature phenotype characterized by expression of the autoimmune regulator Aire, which activates the transcription of numerous genes encoding tissue-restricted self-antigens. The mechanisms that control mature Aire(+) mTEC development in the postnatal thymus remain poorly understood. We demonstrate here that, although either CD4(+) or CD8(+) thymocytes are sufficient to sustain formation of a well-defined medulla, expansion of the mature mTEC population requires autoantigen-specific interactions between positively selected CD4(+) thymocytes bearing autoreactive T cell receptor (TCR) and mTECs displaying cognate self-peptide-MHC class II complexes. These interactions also involve the engagement of CD40 on mTECs by CD40L induced on the positively selected CD4(+) thymocytes. This antigen-specific TCR-MHC class II-mediated crosstalk between CD4(+) thymocytes and mTECs defines a unique checkpoint in thymic stromal development that is pivotal for generating a mature mTEC population competent for ensuring central T cell tolerance.

The cytokine RANKL produced by positively selected thymocytes fosters medullary thymic epithelial cells that express autoimmune regulator.

The thymic medulla provides a microenvironment where medullary thymic epithelial cells (mTECs) express autoimmune regulator and diverse tissue-restricted genes, contributing to launching self-tolerance. Positive selection is essential for thymic medulla formation via a previously unknown mechanism. Here we show that the cytokine RANK ligand (RANKL) was produced by positively selected thymocytes and regulated the cellularity of mTEC by interacting with RANK and osteoprotegerin. Forced expression of RANKL restored thymic medulla in mice lacking positive selection, whereas RANKL perturbation impaired medulla formation. These results indicate that RANKL produced by positively selected thymocytes is responsible for fostering thymic medulla formation, thereby establishing central tolerance.

A safe method for marking small pulmonary nodules with crystal violet.

INTRODUCTION: The number of cases of wedge resection of small-sized pulmonary nodules performed under video-assisted thoracoscopic surgery (VATS) is increasing. Computed tomography (CT)-guided marking with hook wires has been used to locate the nodules that are not identifiable under VATS. However, this method is invasive and is associated with a risk of complications. METHODS: We evaluated the usefulness of marking the pleural surface above the nodule using crystal violet for 22 small-sized pulmonary nodules. Following the collapse of the lung, a long stick with a cotton tip dipped in crystal violet was inserted from the thoracic port or a small thoracotomy, and was placed against the inside of the chest wall right above the nodule with reference to the preoperative CT image. The lung was then expanded, and the crystal violet-infiltrated tip stained the visceral pleura. Regardless of the marking point, wedge resection of the lung was performed. To evaluate the accuracy of the marking, we measured the distance from the center of the marking to the point on the visceral pleural nearest to the nodule (DMN) in the resected lung specimen. RESULTS: This marking method caused no morbidity during or after the operation. The DMN ranged between 0 and 50 mm (mean ± SD 18.2 ± 12.6 mm). In 18 of 22 cases (81.8%), the DMN was 20 mm or less. CONCLUSIONS: The intraoperative marking method using crystal violet was performed with reasonable accuracy. It also caused no morbidity. It was easy and non-invasive. This method can be used in the cases in which CT-guided percutaneous marking is not feasible due to the nodule's location.

Complications of bronchial stapling in thoracic surgery.

OBJECTIVE: The use of staplers for thoracic surgery has been widely accepted and regarded as a safe procedure. However, complications of stapling are occasionally experienced. The aim of this retrospective study was to analyze complications of bronchial stapling. METHODS: A retrospective multi-institutional review was conducted by the Central Japan Lung Cancer Surgery Study Group, comprising 29 institutions. All instances of bronchial stapling in thoracic surgery were reviewed during the research period. RESULTS: Bronchial stapling was performed 2,030 times, using 36 kinds of staplers. The total number of complications related to stapling was 36 (1.8 %); 31 events occurred intraoperatively and five events occurred postoperatively. The intraoperative complications were air leakage (N = 20) and stapling failure (N = 11), which were caused by stapler-tissue thickness mismatch (N = 17), stapler defect (N = 3), tissue fragility (N = 2), and unknown reasons (N = 9). In all 31 cases, intraoperative complications were recovered intraoperatively with additional suturing, and no further complications were observed postoperatively. The postoperative complications were bronchopleural fistula (BPF) (N = 4) and bleeding from the chest wall (intercostal artery) (N = 1). The rate of BPF was 0.2 % (4 of 2,030). Two of four BPFs induced critical conditions. Postoperative bleeding was caused by the use of Duet TRS(TM). Both total complications and BPF occurred more frequently in the main bronchus than in the lobar or segmental bronchus. No relationship was seen between the incidence of complications and cartridge colors in lobar bronchial stapling. The compression types of staplers were associated with the incidence of complication. CONCLUSIONS: Intraoperative and postoperative complications of bronchial stapling were studied. Generally, bronchial stapling in recent thoracic surgery was safe, but rare postoperative complications may induce critical conditions. Knowledge of potential complications and causes of bronchial stapling may decrease the incidence of stapling complications.

Clinicopathological analysis of small-sized anterior mediastinal tumors.

PURPOSE: The purpose of this study was to determine the clinicopathological findings and prognosis of small-sized anterior mediastinal tumors (SSAMTs). METHODS: A retrospective study was conducted on 43 patients who underwent surgery between January 1989 and December 2011 for SSAMTs. RESULTS: From the preoperative radiological findings, the tumors were classified into solid (n = 28) and cystic lesions (n = 15). The pathological diagnoses of the solid lesions included thymoma (n = 24), thymic carcinoma (n = 1), mucosa-associated lymphoid tissue lymphoma (n = 1), teratoma (n = 1) and neurofibroma (n = 1), and those of the cystic lesions included thymic cysts (n = 8), thymoma (n = 3), bronchogenic cysts (n = 2), teratoma, (n = 1) and a pericardial cyst (n = 1). The 27 thymomas were composed of stages I (n = 22), II (n = 3), III (n = 1) and IVb (n = 1). The overall survival in the 43 patients was 97.1 % at 5 years. In the 28 patients with solid lesions, the overall survival was 95.8 % at 5 years. All patients with cystic lesions were still alive at the last follow-up. CONCLUSION: Cystic lesions of SSAMTs were benign lesions or stage I thymoma, and most of the solid lesions of SSAMTs were stage I or II thymomas. SSAMTs are good candidates for video-assisted thoracic surgery procedures, as conversion to sternotomy can be selected based on the intraoperative findings of pericardial invasion and a rapid pathological diagnosis of thymic carcinoma.

Successful treatment of simultaneous malignant pleural mesothelioma and pulmonary adenocarcinoma: A case report.

The present report described the case of a 74-year-old male patient with asbestos exposure whose chest computed tomography revealed a right lower lobe nodule and right pleural effusion. Pleural biopsy led to the diagnosis of epithelial malignant pleural mesothelioma (cT2N0M0, stage IB). Combination therapy with cisplatin + pemetrexed led to the complete remission of malignant pleural mesothelioma; however, the right lower lobe nodule grew in size over time. The patient was subsequently diagnosed with lung adenocarcinoma (cT1aN0M0, stage IA1) by computed tomography-guided biopsy performed 18 months after chemotherapy initiation and achieved remission of lung adenocarcinoma with stereotactic radiotherapy. The patient was alive without recurrence at the 12-month follow-up. The present case illustrated that multiple active regimens are currently available for malignant pleural mesothelioma and lung cancer that can aid in the treatment of complex cases.

Middle lobe preservation and fixation: right upper and lower sleeve bilobectomy. How to do it.

We herein report the case of a 65-year-old female with primary lung cancer who underwent a right upper and lower sleeve bilobectomy. The radiological findings revealed that the tumor was located in the superior segment of the right lower lobe and had invaded the posterior segment of the upper lobe and the truncus intermedius. We performed a right upper and lower sleeve bilobectomy. A latissimus dorsi flap was utilized to separate the thoracic cavity into upper and lower portions, and the preserved middle lobe was fixed in the upper portion to prevent torsion. Postoperative radiography showed good expansion of the middle lobe.

Pedunculated solitary fibrous tumor of the pleura manifesting as a migrating chest mass: report of a case.

We report the case of solitary fibrous tumor of the pleura, which appeared to change its location. A computed tomography (CT) scan done at a previous hospital showed a tumor in the posterior mediastinum, suggesting that it was neurogenic. However, on the initial preoperative CT scan, the tumor seemed to have moved anteriorly, but when contrast material was injected; the tumor appeared in its original position. Video-assisted thoracoscopic surgery (VATS) revealed a pedunculated and free-moving tumor, originating from the visceral pleura. We diagnosed this unusual migrating tumor as a pedunculated solitary fibrous tumor of the pleura.

Excision repair cross complementation group 1 polymorphisms predict overall survival after platinum-based chemotherapy for completely resected non-small-cell lung cancer.

BACKGROUND: It has been reported that the expression of excision repair cross-complementation group 1 (ERCC1) protein predicts the effect of platinum-based chemotherapy and overall survival in the several cancers. And there are some reports suggesting that the polymorphism of the ERCC1 may predict the effect of platinum-based chemotherapy and survival of the patients. We have already reported that the expression of ERCC1 protein predicts survival after platinum-based chemotherapy for 90 completely resected non-small-cell lung cancers (NSCLC). MATERIALS AND METHODS: We investigated the ERCC1 polymorphisms (C8092A and C118T) whether these factors influence for the prognosis of these 90 NSCLC patients treated with platinum-based chemotherapy. RESULTS: Two of the ERCC1 polymorphisms, C8092A and C118T, affected the prognosis of the NSCLC patients who received adjuvant and/or neoadjuvant platinum-based chemotherapy. The wild type, C/C of the codon 8092, was associated with better prognosis than C/A or A/A types (P=0.0154) and the wild type C/C of the codon 118 was associated with better prognosis than C/T or T/T types (P=0.0307). This effect was not seen in an independent group of 55 completely resected NSCLC patients who were treated with surgery alone. The combination of low expression of ERCC1 protein together with the C/C type codon 8092 and C/C type codon 118 polymorphism of the ERCC1 gene was associated with the best prognosis. CONCLUSIONS: Our data seem to suggest that the ERCC1 protein expression and polymorphism of ERCC1 may predict the survival of patients who are treated with platinum-based chemotherapy.

LKB1 gene alterations in surgically resectable adenocarcinoma of the lung.

PURPOSE: Germline mutations of LKB1 (also known as SKT11; locus 19p13.3) cause the occurrence of autosomal dominant Peutz-Jeghers syndrome (PJS). Nearly half of the non-small cell lung cancer (NSCLC) cell lines and one-third of lung adenocarcinoma in Caucasian patients have an LKB1 mutation. METHODS: This study examined the mutational hot spots of the LKB1 gene in surgical resectable lung adenocarcinoma. Exons 1, 6, and 7 of the LKB1 gene were sequenced in 174 Japanese patients with lung adenocarcinoma (including 157 men and 17 women). RESULTS: Only five patients had LKB1 gene alterations (2.9%). All of them were male smokers, and no LKB1 mutation was observed in any of the females. The details of LKB1 alterations were: one 5 bp deletion in intron 5, one Gly to Phe substitution at codon 279 of exon 6, and three Pro to Leu substitutions at codon 281 of exon 6. The P281L alteration and 5 bp deletion in the intron 5 were found to be germline polymorphisms. The G279F was confirmed to be a novel somatic mutation. None of the five patients with an LKB1 alteration showed either an EGFR or K-ras mutation. CONCLUSION: The LKB1 gene alteration is rare in Japanese patients with lung adenocarcinoma, and is generally limited to male smokers.

CHRNA5 gene D398N polymorphism in Japanese lung adenocarcinoma.

BACKGROUND: Recently, to identify genetic factors that modify lung cancer risk, CHRNA5 non-synonymous variant amino acid position 398 (D398N) was identified. The site was a highly conserved in the second cellular loop of the nicotinic acetylcholine receptor subunit protein. MATERIALS AND METHODS: We have investigated CHRNA5 gene polymorphism status in 302 surgically treated lung adenocarcinoma cases from Nagoya City University Hospital. The presence or absence of CHRNA5 polymorphism was analyzed by direct sequences. EGFR mutations status was already investigated and reported. RESULTS: We detected nine cases (2.98%) of CHRNA5 polymorphism (D398N) in our cohort. Total EGFR mutations were present in 129 patients (42.7%). The polymorphism statuses were not correlated with gender (women; 2.1% versus men; 3.7%, P = 0.5119), smoking status (never smoker; 2.0% versus smoker; 4.0%, P = 0.3339), pathological stages (stage I; 2.6% versus stage II-IV; 3.8%, P = 0.7246), and EGFR mutation status of the lung adenocarcinomas (mutation; 2.3% versus wild type; 3.7%, P = 0.7373). In this analysis, CHRNA5 polymorphism (D398N) patients had significantly worse prognosis (5/9 were dead; mean survival = 27.1 mo) than the patients with CHRNA5 wild type (74/293 were dead; mean survival = 113.9 mo) (log-rank test; P = 0.0146). CONCLUSION: Although CHRNA5 polymorphism is rare from Japanese lung cancer, polymorphism status might be correlated with shorter survival.

Thymoma with dissemination: efficacy of macroscopic total resection of disseminated nodules.

BACKGROUND: Advanced thymomas with disseminated nodules are difficult to manage, and the treatment strategy remains undefined. METHODS: A total of 28 thymoma patients with pleural and/or pericardial disseminated nodules were treated at Nagoya City University Hospital. Among them, 21 patients underwent resection of thymoma and pleural disseminated nodules. These patients were reviewed in the present study. RESULTS: Preoperative steroid pulse therapy was performed in 14 patients. Macroscopic total resection of all tumors was achieved in 15 patients. Postoperative adjuvant radiotherapy was performed for the mediastinum in 20 patients and hemithoracic irradiation (HTR) in 11 patients. The overall survival rate of operated 21 patients was 73.1% at 5 years. The patients who underwent resection showed a better prognosis than the patients without resection (p = 0.0006). Relapse was diagnosed in 14 of 21 patients who underwent resection. Disease-free survival was 67.5% at 1 year, 39.8% at 3 years, and 13.3% at 5 years. HTR alone did not improve the disease-free survival. Among the patients who underwent total resection, relapse-free survival was better than in the patients with subtotal resection (p = 0.009). Achievement of a trimodality therapy with preoperative steroid pulse, total resection, and postoperative HTR was associated with prolonged relapse-free survival in the operated patients (p = 0.027, hazard ratio 6.452). CONCLUSIONS: Pursuing total resection for thymoma and disseminated nodules may be beneficial for stage IV thymoma. The combination of preoperative steroid pulse therapy, macroscopic total resection, and postoperative HTR may prolong the interval to relapse, but it did not lead to cure.

Post-irradiation constrictive pericarditis following thymoma treatment: a report of two cases.

Whole pericardial irradiation may be performed for mediastinal malignancies with pericardial dissemination or malignant pericardial effusion. Case 1 is a 57-year-old woman with a B1 thymoma, Masaoka stage IVa. She underwent whole pericardial irradiation and suffered post-irradiation constrictive pericarditis 3 years later. Diuresis, catecholamine infusions, drainage, and pericardiectomy were performed. However, she died of heart failure after 4 years and 1 month due to constrictive pericarditis. Case 2 is a 56-year-old woman with myasthenia gravis and a B2 thymoma, Masaoka stage III. She underwent an extended thymectomy with partial resection of the lung and pericardium and received adjuvant radiation therapy of the whole pericardium. She was affected by post-irradiation constrictive pericarditis 7 months later, for which she underwent pericardiectomy. However, her constrictive pericarditis remained. In conclusion, we report two advanced thymoma cases with post-irradiation constrictive pericarditis. Indicators for whole pericardial irradiation should be determined strictly and carefully.

Investigation of neurotrophic tyrosine kinase receptor 1 fusions and neurotrophic tyrosine kinase receptor family expression in non-small-cell lung cancer and sensitivity to AZD7451 in vitro.

Advances in the molecular segmentation of lung cancer has raised the possibility that neurotrophic tyrosine kinase receptor (NTRK) 1 fusions and NTRK1-3 expression may be promising molecular targets for future therapeutic interventions. We investigated the antitumor effects of a selective pan-NTRK inhibitor, AZD7451, by evaluating its antiproliferative effects on the KM12 cell line (a colorectal cancer cell line harboring a tropomyosin-NTRK1 fusion) and the H460 and H810 cell lines [large-cell neuroendocrine carcinoma (LCNEC) cell lines expressing NTRK2]. Relative quantitative polymerase chain reaction (qPCR) was performed to measure the mRNA levels of the NTRK1-3 tyrosine kinase domain using cDNA extracted from KM12, H460 and H810 cells. The cultures were grown in 6-well plates at a density of 1.0×106 cell/well and treated with AZD7451 at different doses (1, 2.5, 4, 5, 7.5 and 10 nM) using dimethyl sulfoxide as a control. Following a 24-h incubation, the number of surviving cells was measured using a hemocytometer. Furthermore, we performed western blotting of the high-affinity nerve growth factor receptor (TRKA) and NTRK2 (TRKB) proteins and monitored the effects on the downstream signaling pathways Akt and ERK in these cell lines following treatment with AZD7451 (KM12 and H460: 0, 1 and 5 nM; H810: 0 and 5 nM). Immunohistochemical analyses of the surgically resected samples were also performed, using anti-NTRK1,2 antibodies. We performed reverse-transcription PCR and direct sequencing to investigate NTRK fusions in 268 patients; however, were unable to confirm the presence of NTRK fusions in this cohort. Further immunohistochemical analyses of the primary patient samples demonstrated that none of 61 tumors had NTRK1 overexpression and 7 of 39 samples exhibited NTRK2 expression, including 1 LCNEC sample. The qPCR results from the KM12 cell line revealed an apparent increase and overexpression of NTRK1 mRNA levels, while H460 cells exhibited a modest increase and the H810 cell line showed no apparent increase in the expression of any NTRK1-3 isoforms. There were no increases in the NTRK2 mRNA levels in any of the three cell lines, although KM12 and H460 cells exhibited low levels of NTRK2 expression. In vitro growth and proliferation of the KM12 cell line harboring the NTRK1-fusion was found to be potently inhibited by AZD7451 at a concentration of 2 nM. The proliferation of H460 cells was also found to be inhibited at a concentration of 5 nM, while there was no apparent inhibitory effect of AZD7451 on the growth or proliferation of H810 cells. Western blotting of KM12 cells treated with AZD7451 also revealed a potent inhibition of TRKA phosphorylation following AZD7451 treatment. Analysis of H460 cells confirmed the expression and inhibition of phosphorylation of NTRK2, whereas there was little to no expression of TRKA/B in H810 cells. Subsequent in vitro analysis of cell lines treated with the pan-TRK inhibitor AZD7451 suggested that the proliferation of KM12 and H460 cells was significantly inhibited by AZD7451, while H810 cells expressing low levels of wild-type NTRK1-3 were not inhibited. Based on these results, there is potential for a NTRK-dependent proliferation driver in a subpopulation of lung cancer patients with NTRK expression. In addition, pharmacological inhibition with a NTRK inhibitor, such as AZD7451, in cells harboring NTRK1 fusions, may be associated with beneficial antitumor effects.

Genetic profiling of thymic carcinoma using targeted next-generation sequencing.

OBJECTIVES: Thymic carcinoma is a rare mediastinal neoplasm and little is known about its tumorigenesis. There is no effective treatment except for complete resection, and the prognosis of advanced cases is poor. To identify the mutations associated with tumorigenesis, we analyzed genetic profile of thymic carcinoma using targeted next-generation sequencing. MATERIALS AND METHODS: We sequenced about 409 cancer-related genes in 12 thymic squamous cell carcinoma tissues including 10 tumor/normal tissue pairs using Ion AmpliSeq Cancer Panel and Ion PGM Sequencer. We filtered the mutations with Ingenuity Variant Analysis, SIFT, PolyPhen-2, and PROVEAN. RESULTS AND CONCLUSION: Twenty-five candidate mutations in 24 genes were identified, including five tyrosine kinase genes (KIT, DDR2, PDGFRA, ROS1, IGF1R). There was no recurrent mutation among the samples studied. The KIT exon 11 deletion mutation in 1 patient was an activating mutation and may be an oncogenic driver mutation. Genetic profiling of thymic carcinoma using targeted next-generation sequencing was performed. The mutation status of thymic squamous cell carcinoma is highly heterogeneous.

Prognosis of recurrent non-small cell lung cancer following complete resection.

Prognosis following recurrence subsequent to complete resection of non-small-cell lung cancer (NSCLC) is considered a multifactorial process dependent on clinicopathological, biological and treatment characteristics. Gefitinib was approved for lung cancer treatment in Japan in 2002. The aim of the current study was to quantify the prognostic effects of these characteristics on post-recurrence prognosis. In total, 127 NSCLC patients were analyzed who underwent complete resection and subsequently had recurrent cancer. The correlation between characteristics of the initial and recurrent disease with post-recurrence prognosis was investigated. The factors clearly associated with post-recurrence prognosis using Cox proportional hazards models were age at recurrence (those <65 years of age typically had better prognoses) and interval between initial resection and recurrence (intervals of <1 year accompanied a worse prognosis). Epidermal growth factor receptor (EGFR) mutant patients treated with EGFR tyrosine kinase inhibitors (TKIs), exhibited the longest median survival following recurrence (37.4 months) in the sample. Treatment, particularly EGFR TKIs for recurrent NSCLC, was observed to significantly prolong survival. The results of the study highlight that various treatment modalities according to the clinical background of the patient should be considered in patients with postoperative recurrent NSCLC.

APOBEC3B gene overexpression in non-small-cell lung cancer.

Recent study results have demonstrated that a subclass of apolipoprotein B mRNA-editing enzyme, catalytic polypeptide-like (APOBEC) cytidine deaminase may induce mutation clusters in various types of cancer. From the Cancer Genome Altas, an APOBEC mutation pattern was identified in bladder, cervical, breast, head and neck and lung cancers. In the present study, APOBEC3B mRNA expression was investigated using quantitative reverse transcription-polymerase chain reaction (RT-qPCR) assay using LightCycler in surgically treated non-small-cell lung cancer (NSCLC) cases. Additionally, 88 surgically removed Japanese NSCLC cases were analyzed for mRNA level. The results showed that APOBEC3B/ß-actin mRNA levels were significantly higher in lung cancer (1,598.481±6,465.781) when compared to adjacent normal lung tissues (2,116.639±8,337.331, P=0.5453). The tumor/normal (T/N) ratio of APOBEC3B/ß-actin mRNA levels was not different within the gender, age, smoking status and pathological stages. The T/N ratio of APOBEC3B/ß-actin mRNA levels was not significantly different in epidermal growth factor receptor (EGFR) or Kras mutation-positive cases as compared to the wild-type cases.

Genotype analysis of the NRF2 gene mutation in lung cancer.

Nuclear factor (erythroid derived 2)-like 2 (NRF2, gene name NFE2L2) gene mutations have been previously identified in lung cancers. The constitutive activation of NRF2 resulting from gene mutations has been correlated with the poor prognosis of patients with squamous cell lung cancer. However, DNA sequencing using PCR methods described to date is time-consuming and requires significant quantities of DNA. Thus, this existing approach is not suitable for a routine pre-therapeutic screening program. We genotyped the NRF2 gene mutation status in 262 surgically treated lung cancer cases using LightCycler analysis. The presence of the NRF2 gene mutation was confirmed by direct sequencing. We detected 6 cases (2.3%) with NRF2 gene mutations in our cohort, particularly smokers (P=0.04) with squamous histology (P=0.0001). NRF2 gene mutations were present in 10% (6/60) of the lung squamous cell carcinoma (SqCC) cases. The NRF2 gene mutation was exclusive of epidermal growth factor receptor mutations. The NRF2 gene mutation occurred with a tendency towards a higher frequency in male patients. Patients with the NRF2 gene mutation (n=22, 11 succumbed to disease) had a significantly worse prognosis when compared with the patients with the wild-type NRF2 gene (n=521, 98 succumbed to disease) from a larger cohort study (log-rank test, P<0.0001) even upon multivariate analysis. In our study, NRF2 gene mutations played a role in the prognosis of patients with SqCC of the lung.