A Novel Filtration Membrane for Clustered Circulating Tumor Cell Extraction: A Prospective Feasibility Study.

BACKGROUND/AIM: Circulating tumor cells (CTCs) have garnered attention as biomarkers for therapeutic response and prognosis in malignant neoplasms. Nonetheless, existing literature predominantly relies on surrogate markers of tumor cells or focuses on single-cell CTC, failing to adequately address the challenge of detecting cluster-forming CTCs, which bear considerable prognostic implications. This prospective study aims to validate the efficacy of a novel filtration membrane, namely Soft Micro Pore Filter (S-MPF®), for rare cell recovery in detecting CTCs through the analysis of clinical samples. PATIENTS AND METHODS: Patients with confirmed lung cancer or highly suspected lung cancer based on specific criteria (solid tumor size >2.0 cm, serum carcinoembryonic level >7.5 ng/ml, maximum standard uptake value derived from fluorodeoxyglucose-position emission tomography >2.9) were included in the study. CTCs were extracted from preoperative peripheral arterial blood samples using S-MPF®, and the validity of the filtration system was positively verified. RESULTS: Out of the 25 enrolled patients, 23 had lung cancer. CTC positivity was observed in 17 cases (73.9%), whereas cluster CTC positivity was observed in 16 cases (69.6%), with a median count of two clusters. Single CTC positivity was observed in 11 cases (52.1%), with a median count of one cell. CONCLUSION: The utilization of the newly developed S-MPF® filtration membrane exhibited a high rate of CTC identification, demonstrating its suitability for clinical applications.

Verification of A New Filter for Isolation of Circulating Tumor Cells by Only Blood Filtration.

BACKGROUND/AIM: Since circulating tumor cells (CTCs) are precursors of metastatic lesions, extracting CTCs from whole blood is useful in obtaining information for cancer treatment. One of the CTC isolation methods is the size selection method; however, since the conventional methods are expensive and cumbersome, we developed an affordable and simple filter, whose usefulness is verified in this study. MATERIALS AND METHODS: The new filter [hereafter, soft micropore filter (S-MPF)] is made up of a polyethylene film with a thickness of 15 µm and conical pores having a diameter of 8-10 µm, which are opened uniformly (opening rate, 20%). This filter can filter whole blood by free-falling under gravity. The possibilities of the filter's usage for model CTC isolation, immunostaining, short-term cell culture, and gene mutation detection in extracted model CTCs were verified. RESULTS: S-MPF was able to extract model CTCs with an isolation rate of up to 15%. These model CTCs were detected by cytology, immunostaining, and culture by short-term incubation of filtered cells. Furthermore, genetic mutations were identified in the cultured cells. In addition, CTC isolation from the peripheral blood of patients with lung cancer was demonstrated by setting the volume of collected blood to 15 ml to prevent a low recovery rate. CONCLUSION: The S-MPF can be used to extract model CTCs quickly and easily. Moreover, cytological diagnosis, immunostaining, short-term culture, and gene mutation search are possible with this filter. Given its proven applicability in clinical samples, this filter can be used in clinical settings.

Concomitant Resection of Left Ventricular Hemangioma and Lung Cancer With Ground-Glass Opacity.

We report a case of concomitant left ventricular tumor and lung lesion with ground-glass opacity without preoperative confirmation of malignancy. To obtain definitive diagnosis, a wedge lung resection was performed through a median sternotomy. After confirmation of a negative margin by frozen section, the cardiac tumor was resected through a left anterior ventriculotomy. Histopathologic analysis identified a rare cardiac hemangioma and an adenocarcinoma with pTis, N0, M0, stage 0. Postoperative recovery was uneventful with intact cardiopulmonary functions despite the risk of low cardiac output attributable to ventriculotomy.

Higher Tissue Levels of Thymidylate Synthase Determined by ELISA Are Associated with Poor Prognosis of Patients with Lung Cancer.

Thymidylate synthase (TS) is essential in thymidylate biosynthesis and DNA replication. Dihydropyrimidine dehydrogenase (DPD) is a rate-limiting enzyme in pyrimidine catabolism and is important in catabolism of 5-fluorouracil (5-FU). The significance of TS and DPD expressed in lung cancer remains controversial. Here we analyzed the relationship between TS and DPD expression and clinicopathological features of lung cancer. Enzyme-linked immunosorbent assays (ELISAs) were used to measure TS and DPD levels in paired tumor and non-tumor lung tissues obtained from 168 patients (107 adenocarcinomas, 39 squamous cell carcinomas, and 22 others), who had operations at the Shinshu University Hospital from 2004 to 2007 and were followed up for a median of 57.0 months. TS and DPD expression levels were higher in tumor tissues, and TS expression levels were significantly lower in adenocarcinomas than those in other subtypes. In addition, patients with low TS levels survived longer compared with patents with high TS levels. By contrast, DPD expression levels were not correlated with overall patient survival. Importantly, patients with low TS and DPD levels exhibited significantly prolonged survival than those with high TS and DPD. Among the 168 patients, 59 patients were treated with tegafur-uracil (UFT), a DPD-inhibitory fluoropyrimidine, and the UFT-treated patients with high TS and high DPD levels showed worst prognosis. Our study demonstrates a significant correlation between low TS expression levels and long-term prognosis of patients with lung cancer. Thus, ELISA is a clinically useful method to measure TS and DPD expression in lung cancer tissues.

Characterization of a novel thermostable N-acylhomoserine lactonase from the thermophilic bacterium Thermaerobacter marianensis.

Thermaerobacter marianensis is an extremely thermophilic bacterium, which was isolated from the Mariana Trench, with an optimal growth temperature of approximately 75 °C. N-Acylhomoserine lactone (AHL) is a quorum-sensing signal molecule used by many gram-negative bacteria. Here, we report the identification of an AHL-degrading gene homolog (designated aiiT) in the genome of T. marianensis JCM 10246. AiiT has 59.7%, 21.2%, and 11.2% identity to AhlS from Solibacillus silvestris, AiiA from Bacillus cereus, and AidC from Chryseobacterium sp., respectively. Homologs of aiiT were also found in Thermaerobacter nagasakiensis, T. composti, and T. subterraneus. A purified AiiT-maltose binding fusion showed high AHL-degrading activity against N-hexanoyl-L-homoserine lactone, N-octanoyl-L-homoserine lactone, and N-decanoyl-L-homoserine lactone at temperatures ranging from 40 to 80 °C. HPLC analysis revealed that AiiT functions as an AHL-lactonase that catalyzes AHL ring opening by hydrolyzing lactones. AiiT displayed maximal activity at high temperatures (60-80 °C) and showed higher thermostability than other AHL lactonases.

Tumor size and computed tomography attenuation of pulmonary pure ground-glass nodules are useful for predicting pathological invasiveness.

OBJECTIVES: Pulmonary ground-glass nodules (GGNs) are occasionally diagnosed as invasive adenocarcinomas. This study aimed to evaluate the clinicopathological features of patients with pulmonary GGNs to identify factors predictive of pathological invasion. METHODS: We retrospectively evaluated 101 pulmonary GGNs resected between July 2006 and November 2013 and pathologically classified them as adenocarcinoma in situ (AIS; n = 47), minimally invasive adenocarcinoma (MIA; n = 30), or invasive adenocarcinoma (I-ADC; n = 24). The age, sex, smoking history, tumor size, and computed tomography (CT) attenuation of the 3 groups were compared. Receiver operating characteristic (ROC) curve analyses were performed to identify factors that could predict the presence of pathologically invasive adenocarcinomas. RESULTS: Tumor size was significantly larger in the MIA and I-ADC groups than in the AIS group. CT attenuation was significantly greater in the I-ADC group than in the AIS and MIA groups. In ROC curve analyses, the sensitivity and specificity of tumor size (cutoff, 11 mm) were 95.8% and 46.8%, respectively, and those for CT attenuation (cutoff, -680 HU) were 95.8% and 35.1%, respectively; the areas under the curve (AUC) were 0.75 and 0.77, respectively. A combination of tumor size and CT attenuation (cutoffs of 11 mm and -680 HU for tumor size and CT attenuation, respectively) yielded in a sensitivity and specificity of 91.7% and 71.4%, respectively, with an AUC of 0.82. CONCLUSIONS: Tumor size and CT attenuation were predictive factors of pathological invasiveness for pulmonary GGNs. Use of a combination of tumor size and CT attenuation facilitated more accurate prediction of invasive adenocarcinoma than the use of these factors independently.

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.

An intrathoracic low-grade fibromyxoid sarcoma arising from the chest wall with massive pleural effusion.

We herein report a case of an intrathoracic low-grade fibromyxoid sarcoma arising from the chest wall and associated with massive pleural effusion. A 70-year-old man presented with a persistent cough. A chest computed tomography scan revealed a large mass in the right pleural cavity with massive pleural effusion. No malignant cells were recognized in the pleural effusion by thoracentesis. A malignant soft tissue tumor was suspected, and surgery was performed. The tumor arose from the posterior chest wall and was resected with the connected chest wall. The definitive diagnosis was a low grade fibromyxoid sarcoma. Because the posterior margin of the chest wall was microscopically tumor positive, postoperative irradiation was performed. The patient has now been followed up for 30 months with no evidence of recurrence.

Complete genome sequence and characterization of the N-acylhomoserine lactone-degrading gene of the potato leaf-associated Solibacillus silvestris.

N-Acylhomoserine lactones (AHLs) are used as quorum-sensing signal molecules by many gram-negative bacteria. We have reported that Solibacillus silvestris, which was isolated from the potato leaf, has AHL-degrading activity. To identify the AHL-degrading gene, whole genome sequencing of S. silvestris StLB046 was performed by using pyrosequencing technology. As the result of the BLAST search, one predicted ORF (ahlS) showed slight similarity to AiiA-like AHL lactonase from Bacillus cereus group. Escherichia coli harboring the ahlS-expressing plasmid showed high AHL-degrading activity. The ahlS-cording region was also amplified by PCR from the other potato leaf-associated and AHL-degrading S. silvestris strains. Purified AhlS as a maltose binding fusion protein showed high AHL-degrading activity and catalyzes AHL ring opening by hydrolyzing lactones. In addition, expression of ahlS in plant pathogen Pectobacterium carotovorum subsp. carotovorum attenuated maceration of the potato slices. Our results suggest that AHL-degrading activity of ahlS might perform useful functions such as useful biocontrol agents.

Different morbidity after pneumonectomy: multidrug-resistant tuberculosis versus non-tuberculous mycobacterial infection.

To assess whether there is any difference in postoperative morbidity and mortality after pneumonectomy between patients with multidrug-resistant tuberculosis (MDR-TB) and patients with non-tuberculous mycobacterial (NTM) infections. Between January 2000 and December 2007, 61 patients with MDR-TB and 60 patients with NTM infections underwent 66 and 64 pulmonary resections, respectively. Of these, 33 patients were analyzed who underwent a pneumonectomy, including 22 patients with MDR-TB (seven right, 15 left) and 11 patients with NTM infections (seven right, four left). All bronchial stumps were covered with the latissimus dorsi. Patients with NTM infections were predominantly more female, older, thinner, and presented with a higher frequency of culture-positive sputum at operation than patients with MDR-TB. Operative mortality was zero. Morbidities were bronchial stump dehiscence (n=1) and mycobacterial empyema (n=1) for patients with MDR-TB, and acute respiratory failure (n=1), bronchial stump dehiscence (n=5) and mycobacterial empyema (n=2) for patients with NTM infections. Prevalence of bronchial stump dehiscence was significantly higher in patients with NTM infections (P=0.010). Five of six dehiscences occurred after right pneumonectomy. The optimal management of the bronchial stump in the setting of pneumonectomy for NTM infections needs further investigation.

Aggressive surgical treatment of multidrug-resistant tuberculosis.

OBJECTIVE: Because extensively drug-resistant tuberculosis has emerged, adequate control of drug-resistant tuberculosis has become increasingly important. We report on our experience using liberal adjuvant resectional surgery as part of aggressive treatment for multidrug-resistant tuberculosis. METHODS: We retrospectively reviewed the records of 56 consecutive patients who underwent pulmonary resections for multidrug-resistant tuberculosis between January 2000 and June 2007. There were 42 males and 14 females (mean age, 46 years; range, 22-64 years). Isolates were resistant to a mean of 5.6 drugs (range, 2-10 drugs). Multi-drug regimens employing 3 to 7 drugs (mean, 4.6 drugs) were initiated in all patients. Indications for surgery were a high risk of relapse for 37 patients, persistent positive sputum for 18, and 1 with associated empyema. RESULTS: The 56 patients underwent 61 pulmonary resections (3 completion pneumonectomies, 19 pneumonectomies, 33 lobectomies, and 6 segmentectomies). Bronchial stumps were reinforced with muscle flaps in 54 resections. Operative mortality and morbidity rates were 0% and 16%, respectively. All patients attained postoperative sputum-negative status. Relapse occurred in 5 patients; 3 were converted by a second resection, and 1 responded to augmentation of chemotherapy. Late death occurred for 2 patients without evidence of relapse. Among 54 survivors, 53 (98%) were considered cured. CONCLUSION: Surgical treatment that complements medical treatment has proved safe and efficacious for patients with multidrug-resistant tuberculosis. In an era with extensively drug-resistant tuberculosis, an aggressive treatment approach to multidrug-resistant tuberculosis continues to be justified until a panacea for this refractory disease is available.

A case of unilateral gravid macromastia in 23-year-old Japanese woman associated with elevated serum CA19-9.

We report a rare case of gravid macromastia (GM) treated after delivery. A 23-year-old woman with left breast enlargement was referred to our hospital. Laboratory investigations revealed an elevated serum CA19-9 level of 200.3 U/ml. Gravid macromastia was diagnosed by clinical examination (US, MRI) and 11G mammotome biopsy. Tumorectomy of the left breast and mammoplasty were performed. The mass had proliferated to the exclusion of normal gland. Histological examination revealed abundant proliferation of stromal loose connective tissue and interposed fat cells surrounding normal and lactating lobules. The epithelial cells were positive for CA19-9 on immunohistochemical staining. Serum CA19-9 decreased to normal levels 3 months after operation. GM is exceedingly rare and occurs in less than 0.001-0.003% of all pregnant women. Once established, the condition is likely to continue to successive pregnancies. This benign tumor is sometimes difficult to distinguish from malignant tumors since it shows few histological characteristics and grows rapidly. Attention is necessary to diagnose tumors of the breast during pregnancy.