Treatment of bronchial fistula after extraplural pneumonectomy using flexible bronchoscopy with the administration of OK432, fibroblast growth factor basic and fibrin glue sealant.

Treatment options for bronchial fistula (BF) after pneumonectomy are often limited and carry significant morbidity and mortality. The patient underwent right extrapleural pneumonectomy for malignant pleural mesothelioma had BF without macroscopic fistula found by bronchography. We treated this minor BF using bronchoscopy with the administration of OK-432, fibroblast growth factor basic, and fibrin glue sealant. Two weeks after this treatment, we confirmed the improvement of the fistula by bronchography. Bronchoscopic therapy for BF was useful for a small, early fistula without infection.

Right Lower Lobectomy for an Aberrant Mediastinal Inferior Lobar Artery.

A 74-year-old woman was referred for a right lower lobe consolidation (maximum diameter, 73 mm) pathologically diagnosed as invasive mucinous adenocarcinoma (c-T4 N0 M0, c-stage IIIA). Computed tomography revealed an aberrant mediastinal inferior lobar branch (A6 and common basal artery [A7 to A10]) from the right main pulmonary artery (PA). Right lower lobectomy and lymph node dissection were performed. A mediastinal inferior lobar branch is extremely rare, and this patient with lung cancer underwent right lower lobectomy for all inferior PA branches (A6 and A7 to A10) arising from the main PA into the lower lobe.

The clinical value of circulating tumour cells (CTCs) in patients undergoing pulmonary metastasectomy for metastatic colorectal cancer.

BACKGROUND: Circulating tumour cells (CTCs) are a potential surrogate for distant metastasis and are considered a useful clinical prognostic marker for metastatic colorectal cancer (mCRC). This prospective study evaluated the preoperative CTC count as a prognostic factor for pulmonary metastasectomy in mCRC patients. METHODS: Seventy-nine mCRC patients who underwent curative-intent pulmonary metastasectomy were included. Preoperatively, 7.5 mL of peripheral blood from each patient was quantitatively evaluated for CTCs with the CellSearch® system. The clinical significance of CTC count was evaluated according to Kaplan-Meier analyses and log-rank test. Multivariate analyses of the perioperative variables were performed. RESULTS: The distribution of CTC counts were as follows; 0 in 66 patients (83.5%), 1 in eight patients (10.1%), 2 in three patients (3.8%), and 3 and 6 in one patient (1.3%). The patients with multiple CTCs (CTC count ≥2) had significant shorter disease-free survival (DFS) (P=0.005, median DFS; 19.8 vs. 8.6 months) and overall survival (OS) (P=0.035, median DFS; not reached vs. 37.8 months), respectively. Multivariate analysis showed the patients with multiple CTCs had elevated risk of recurrence [hazard ratio (HR), 3.28; 95% confidence interval (CI), 1.24-8.67; P=0.017]. CONCLUSIONS: The detected rate of CTCs was quite low in mCRC patients who underwent pulmonary metastasectomy. The patient with multiple CTCs had shorter DFS in this study. The larger prospective clinical study is needed to establish the meaning of CTC in mCRC candidate for pulmonary metastasectomy.

Positive correlation between postoperative tumor recurrence and changes in circulating tumor cell counts in pulmonary venous blood (pvCTC) during surgical manipulation in non-small cell lung cancer.

BACKGROUND: In non-small cell lung cancer (NSCLC), circulating tumor cells (CTC) are shed and circulate to the peripheral blood through the pulmonary vein. Previously, CTC count in pulmonary venous blood (pvCTC) was shown to significantly increase after surgical manipulation. Therefore, we assessed the correlation between the changes in the pvCTC count (ΔpvCTC) and clinical outcomes. METHODS: Consecutive patients with peripheral-type, NSCLC, who underwent lobectomy or bi-lobectomy through open thoracotomy, were enrolled prospectively. Before and after lobectomy, 2.5 mL of blood was drawn from the associated lobar pulmonary vein (PV), and was served for the quantitative evaluation of CTC using the CellSearch® system. The cut-off point of ΔpvCTC was determined according to clinical outcomes and ΔpvCTC using receiver operation characteristic (ROC) curve. Then the correlation between ΔpvCTC and clinical outcomes was evaluated by Kaplan-Meier analyses and log-rank test. In addition, the correlation between ΔpvCTC and perioperative variables was assessed. RESULTS: A total of 30 patients were enrolled, tumor recurrence occurred in 11 patients over a median follow-up of 64.4 months. Of these, 7 patients had distant metastasis and 4 had local recurrence. The median ΔpvCTC was 49 cells/2.5 mL, and pvCTC-count was increased during surgical manipulation in 24 patients (80%). We divided patients into two groups based on ΔpvCTC with the cut-off value as 119 cells/2.5 mL according to ROC curve. Significant shorter time to distant metastasis (TDM) (P=0.0123) was observed in high ΔpvCTC group (ΔpvCTC ≥119 cells/2.5 mL) than low ΔpvCTC group (ΔpvCTC <119 cells/ 2.5mL). Neither disease-free survival (DFS) nor overall survival (OS) was significantly correlated with ΔpvCTC. CONCLUSIONS: Increasing pvCTC count during surgical manipulation was significantly correlated with postoperative distant metastasis in completely resected NSCLC patients. Significant shorter TDM was observed in patient with high ΔpvCTC group.

Circulating Tumor Cell Count Can Be a Useful Prognostic Factor in Lung Resection via Cardiopulmonary Bypass.

Tumor resection with cardiopulmonary bypass (CPB) remains controversial in the field of oncology. Here, we present a 57-year-old male patient with locally advanced squamous cell carcinoma. The tumor was located in the left hilum and invaded the left atrium. Complete resection, left pneumonectomy combined with partial left atrium resection, was achieved using CPB. We evaluated the circulating tumor cell (CTC) counts, as a surrogate for micrometastasis, in peripheral blood and the CPB circuit. Both CTC counts were 0, which could indicate local disease without micrometastasis. CTC count may be a useful indicator for tumor resection with CPB in lung cancer.

[Primary Spontaneous Pneumothorax with an Azygos Lobe].

A-21-year old man presented with dyspnea and a chest radiograph showed a right pneumothorax. Chest computed tomography revealed a collapsed lung and floating membrane, which was the lowermost part as a tear-shaped shadow. After the chest tube was inserted and surgical management was performed using a video-assisted thoracoscopic approach. At surgery, the visceral and parietal layers of pleura forming the mesoazygos were not fused, and azygos vein had a partial mobility. There was no adhesion between an upper lobe and visceral pleura. A stapling bullectomy was performed. The azygos lobe is a common malformation and has a reported incidence of 0.05~0.4% on health screening. The presence of an azygos lobe is usually assumed to be of no significance. We report a case and discuss the problems that it posed for surgical management.

Pleural vasculitides of microscopic polyangiitis with asbestos-related plaques.

A 69-year-old man who had been exposed to asbestos for approximately 40 years presented with the complaint of fever and pleuritic chest pain on the right side on deep inspiration. Chest X-ray films showed pleural effusion in the right side. Initial antibiotic treatment was ineffective. The hyaluronic acid level was high in the pleural effusion but no malignant mesotheliomal cells were seen with blind pleural biopsy. Blood chemistry showed a remarkable high titer of myeloperoxidase anti-neutrophil cytoplasmic antibody (MPO-ANCA) and open renal biopsy suggested crescentic glomerulonephritis. The precise pathological examination on the pleura obtained by the open pleural biopsy showed vasculitides and plaque leading to diagnosis of microscopic polyangiitis (MPA). This is a rare case of MPA seen in the pleural arteries.

[Bilateral Pneumothorax due to Pulmonary Metastasis from Angiosarcoma of the Forehead；Report of a Case].

Angiosarcoma is rare but highly malignant tumor arising from vascular endothelial cells. A 85-year-old man with difficulty in breathing for 3 days was referred to our hospital. He had a history of angiosarcoma of forehead 4 months before. A chest computed tomography (CT) scan showed left pneumothorax with multiple cystic changes and ground grass attenuations of bilateral lungs, which had obviously increased in recent 2 months. Pulmonary metastases with secondary pneumothorax was highly suspected by the serial CT findings. He was treated with tube thoracostomy and the instillation of a sclerosing agent (minocycline hydrochloride 200 mg). Seven weeks after his initial presentation, he died from obstructive pneumonia and an autopsy was held. Histologic examinations revealed that the tumor foci were peripheral, multiple and generally formed nodules. These cells were cluster differentiation (CD)31 and CD34 positive and negative for calretinin, cytokeratin, carcinoembryonic antigen (CEA), thyroid transcription factor (TTF-1) and epithelial membrane antigen (EMA). These findings were compatible with pulmonary metastases of angiosarcoma of forehead.

Significant increase in circulating tumour cells in pulmonary venous blood during surgical manipulation in patients with primary lung cancer.

OBJECTIVES: Circulating tumour cells (CTCs) are tumour cells shed from a primary tumour and circulate in the peripheral blood after passing through the drainage vein. In previous studies, we showed that high numbers of CTCs were detected in the drainage pulmonary venous blood of most patients with resectable primary lung cancer, whereas only low numbers of CTCs were detected in the peripheral blood of some patients. Accordingly, this prospective study was conducted to assess changes in CTCs in the drainage pulmonary vein (PV) during lung cancer surgery. METHODS: A total of 30 consecutive peripheral-type primary lung cancer patients who underwent lobectomy (or right upper and middle bilobectomy) through open thoracotomy were included. For each patient, 2.5 ml of blood was sampled from the lobar PV of the primary tumour site before and after surgical manipulation for lobectomy. The CTCs were evaluated quantitatively with the CellSearch® system. RESULTS: Before surgical manipulation, CTCs were detected in PV blood in the majority of patients (22 of 30, 73.3%), although CTCs were detected in peripheral blood in only two patients (6.7%). The median number of CTCs in the PV (pvCTC-count) before surgical manipulation was 4.0 cells/2.5 ml, and there was no significant correlation between pvPV-count and any clinicopathological characteristic, including tumour size, progression and histological type. After surgical manipulation, at the time of completion of the lobectomy, the pvCTC-count significantly increased (median, 60.0 cells/2.5 ml; P = 0.001). The increase in pvCTC-count was significantly associated with microscopic lymphatic tumour invasion (ly); pvCTC-count significantly increased in ly-positive patients (pvCTC-count before and after surgical manipulation, 4.0 and 90.5 cells/2.5 ml, respectively; P = 0.006), but not in ly-negative patients (3.5 and 7.0 cells/2.5 ml, respectively; P = 0.153). The increase in pvCTC-count was not significantly associated with any other clinicopathological factor or with any surgical procedure, including the sequence of vessel interruption. CONCLUSIONS: We documented a significant increase in CTC count in drainage PV blood after surgical manipulation, especially in tumours with lymphatic invasion. We are awaiting survival data at 5 year follow-up examination, which may provide clinical significance of the pvCTC-count.

Frequency of epidermal growth factor receptor mutations in Bangladeshi patients with adenocarcinoma of the lung.

BACKGROUND: Worldwide studies on lung adenocarcinoma have demonstrated a genetic divergence of the epidermal growth factor receptor (EGFR) pathway according to ethnicity, such as higher frequency of activated EGFR mutations among East Asian patients. However, such information is still lacking in some developing countries. METHODS: We investigated the frequency of EGFR mutations among Bangladeshi patients with adenocarcinoma of the lung. Fine-needle aspiration tissue samples were collected from 61 Bangladeshi patients. Polymerase chain reaction-single-strand conformation polymorphism was performed on extracted DNA for mutational analysis of EGFR exons 19 and 21. RESULTS: EGFR mutations were found in 14 of 61 (23.0 %) Bangladeshi patients. There was no significant difference in EGFR mutation rate with regard to patient's age, sex, smoking history, clinical stage of lung cancer, subtypes of adenocarcinoma, and tumor differentiation. CONCLUSION: The present study revealed that the EGFR mutation rate in Bangladeshi patients with adenocarcinoma of the lung was higher than in African-American, Arabian, and white Caucasian patients, and was lower than in East Asia.

Circulating tumor cells (CTCs) in malignant pleural mesothelioma (MPM).

PURPOSE: To investigate the diagnostic and prognostic value of circulating tumor cells (CTCs), a potential surrogate of micrometastasis, in malignant pleural mesothelioma (MPM). METHODS: We prospectively evaluated CTCs in 7.5 mL of peripheral blood sampled from patients with a suspicion of MPM. A semiautomated system was used to capture CTCs with an antibody against the epithelial cell adhesion molecule. RESULTS: Of 136 eligible patients, 32 were finally diagnosed with nonmalignant diseases (NM), and 104 had MPM. CTCs were detected in 32.7 % (34 of 104) of MPM patients but in only 9.4 % (3 of 32) of NM patients (P = 0.011). The CTC count was significantly higher in MPM patients than in NM patients (P = 0.007), and a receiver operating characteristic (ROC) curve analysis showed an insufficient capability of the CTC test in discrimination between MPM and NM, with an area under ROC curve of 0.623 (95 % confidence interval, 0.523-0.723; P = 0.036). Among MPM patients, CTCs were more frequently detected in patients with epithelioid subtype (39.7 %, 31 of 78) than in those with nonepithelioid subtypes (11.5 %, 3 of 26; P = 0.016). Positive CTCs (CTC count ≥ 1) were a significant factor to predict a poor prognosis among epithelioid patients (median overall survival, 22.3 months for positive CTCs vs. 12.6 months for negative CTCs; P = 0.004) and not in nonepithelioid patients (P = 0.649). A multivariate analysis showed that positive CTCs were a significant and independent factor to predict a poor prognosis (hazard ratio, 2.904; 95 % confidence interval, 1.530-5.511; P = 0.001) for epithelioid MPM patients. CONCLUSIONS: CTC was a promising marker in diagnosis and prediction of prognosis in MPM, especially in epithelioid MPM.

Circulating endothelial cell (CEC) as a diagnostic and prognostic marker in malignant pleural mesothelioma (MPM).

BACKGROUND: The purpose of this study was to investigate the diagnostic and prognostic value of circulating endothelial cell (CEC), a potential surrogate of tumor angiogenesis, in malignant pleural mesothelioma (MPM). METHODS: We prospectively evaluated CEC count in 4.0 mL of peripheral blood sampled from patients with a suspicion of MPM. An automated system was used to capture CECs with an anti-CD146 antibody. RESULTS: Of 109 eligible patients, 30 were finally diagnosed with non-malignant diseases, and 79 were with MPM. CEC count was significantly higher in MPM patients than in NM patients (mean CEC count, 120.3 and 39.9, respectively; P = 0.001), and a receiver operating characteristic (ROC) curve analysis showed that CEC provided a significant diagnostic performance in discrimination between MPM and nonmalignant diseases with an area under curve (AUC-ROC) of 0.700 (95 % confidence interval [95 % CI], 0.595-0.806; P = 0.001). Among MPM patients, CEC count was positively correlated with intratumoral microvessel density (MVD), a measurement of tumor angiogenesis (Spearman correlation coefficiency [r] = 0.444; P = 0.001). Higher CEC count (>50) was significantly associated with a poor prognosis (median overall survival, 11.4 months [95 % CI, 7.6-15.2] for higher CEC count patients versus 20.1 months [95 % CI, 16.0-24.2] for lower CEC count patients; P = 0.028). A multivariate analysis showed that higher CEC count was a significant and independent factor to predict a poor prognosis (hazard ratio [HR], 2.24, [95 % CI, 1.24-4.43]; P = 0.009). CONCLUSIONS: CEC, as a surrogate of tumor angiogenesis, was a promising marker in diagnosis and prediction of prognosis in MPM.

Frequent inactivation of the BAP1 gene in epithelioid-type malignant mesothelioma.

In the present study, we analyzed genomic alterations of BRCA1-associated protein 1 (BAP1) in 23 malignant mesotheliomas (MMs), 16 epithelioid and seven non-epithelioid, consisting of 18 clinical specimens and five established cell lines. In examining these samples for homozygous deletions and sequence-level mutations, we found biallelic BAP1 gene alterations in 14 of 23 MMs (61%). Seven of these 14 MMs had homozygous deletions of the partial or entire BAP1 gene, another five had sequence-level mutations, including small deletions, a nonsense mutation, and missense mutations with additional monoallelic deletions, and the remaining two had homozygous mutations without allelic loss. All but one of the 14 BAP1 gene mutations were found in the epithelioid-type MMs; BAP1 mutations were found in 13 of 16 epithelioid-type MMs, but in only one of seven non-epithelioid-type MMs (13/16 vs 1/7; P = 0.005). There was no BAP1 mRNA expression in MMs with biallelic deletion and repressed expression was confirmed in MM specimens with deletion/mutation as compared with Met5a, SV40-transformed normal mesothelial cells. Western blot showed that seven of eight epithelioid MMs analyzed were BAP1 negative. Immunostaining with anti-BAP1 antibody in normal lung tissues revealed clear nuclear staining of normal mesothelial cells. No nuclear staining was observed among BAP1 mutation-positive MM tumors, whereas nuclear staining was observed among BAP1 mutation-negative MM tumors. These results suggest that the lack of the tumor suppressor BAP1 may be more specifically involved in the pathogenesis of epithelioid MM rather than non-epithelioid MM, and would be useful for diagnosis of epithelioid-type MM.

Practical approaches to diagnose and treat for T0 malignant pleural mesothelioma: a proposal for diagnostic total parietal pleurectomy.

Malignant pleural mesothelioma (MPM) remains suffering poor prognosis in spite of recent diagnostic and therapeutic progress. Although there is currently no established evidence, early diagnosis and early intervention may play a key role to improve prognosis of MPM, similarly to other malignancies. As pleural effusion is usually the first clinical sign of MPM, pleural effusion cytology is often the first diagnostic examination to be carried out. Since the sensitivity of pleural effusion cytology is approximately 60%, however, false-negative diagnosis is given to almost half of true MPM patients at this clinical step. One practical way to reduce the number of misdiagnosed MPM is to encourage performing thoracoscopic pleural biopsy unless definitive diagnosis other than MPM is established. There still remain a considerable number of patients with radiological/thoracoscopic T0 MPM who are misdiagnosed with nonspecific pleuritis after a complete investigation including thoracoscopic biopsies. Such patients will turn out to be malignant during follow-up period, although they have the best opportunity for long-term survival if only early therapeutic intervention is given. Currently, we are performing diagnostic total parietal pleurectomy in highly selected patients, who are characterized with strong clinical suspicion, positive pleural effusion cytology but uncertain pathological diagnosis, excellent cardiopulmonary reserve, and with written informed consent for highly invasive diagnostic surgery for pathologically unproven disease.

Frequent deletion of 3p21.1 region carrying semaphorin 3G and aberrant expression of the genes participating in semaphorin signaling in the epithelioid type of malignant mesothelioma cells.

Array-based comparative genomic hybridization analysis was performed on 21 malignant mesothelioma (MM) samples (16 primary cell cultures and 5 cell lines) and two reactive mesothelial hyperplasia (RM) primary cell cultures. The RM samples did not have any genomic losses or gains. In MM samples, deletions in 1p, 3p21, 4q, 9p21, 16p13 and 22q were detected frequently. We focused on 3p21 because this deletion was specific to the epithelioid type. Especially, a deletion in 3p21.1 region carrying seven genes including SEMA3G was found in 52% of MM samples (11 of 14 epithelioid samples). The allele loss of 3p21.1 might be a good marker for the epithelioid MM. A homozygous deletion in this region was detected in two MM primary cell cultures. A heterozygous deletion detected in nine samples contained the 3p21.1 region and 3p21.31 one carrying the candidate tumor suppressor genes such as semaphorin 3F (SEMA3F), SEMA3B and Ras association (RalGDS/AF-6) domain family member 1 (RASSF1A). SEMA3B, 3F and 3G are class 3 semaphorins and inhibit growth by competing with vascular endothelial growth factor (VEGF) through binding to neuropilin. All MM samples downregulated the expression of more than one gene for SEMA3B, 3F and 3G when compared with Met5a, a normal pleura-derived cell line. Moreover, in 12 of 14 epithelioid MM samples the expression level of SEMA3A was lower than that in Met5a and the two RM samples. An augmented expression of VEGFA was detected in half of the MM samples. The expression ratio of VEGFA/SEMA3A was significantly higher in the epithelioid MMs than in Met5a, RMs and the non-epithelioid MMs. Our data suggest that the downregulated expression of SEMA3A and several SEMA3s results in a loss of inhibitory activities in tumor angiogenesis and tumor growth of VEGFA; therefore, it may play an important role on the pathogenesis of the epithelioid type of MM.

Diagnosis of synchronous primary lung adenocarcinomas based on epidermal growth factor (EGFR) gene status: A case report.

The diagnosis of multiple primary lung cancer is sometimes difficult when multiple lung tumors with the same histologic type are identified. We now present a case of synchronous double primary lung adenocarcinomas (one in the right upper lobe and another in the right middle lobe) diagnosed based on mutational analysis of the epidermal growth factor receptor (EGFR) gene, although clinico-pathological findings suggested the diagnosis of intrapulmonary metastasis. After complete resection, pathological sections revealed the similar pathological features of two adenocarcinomas and unexpected subcarinal nodal metastasis. As the L858R mutation within exon 21 of the EGFR gene was identified in the middle-lobe tumor and the subcarinal node but not in the upper-lobe tumor, we diagnosed as double primary cancers. Local mediastinal recurrence after operation has been well-controlled with administration of gefitinib, a EGFR-tyrosine kinase inhibitor, and mutational analysis of the EGFR gene provided important information not only in the diagnosis of double primary cancers but also in decision-making of selection of chemotherapeutic agent.

Well-differentiated papillary mesothelioma with invasion to the chest wall.

Well-differentiated papillary mesothelioma (WDPM) is an uncommon tumor with a papillary architecture, bland cytologic features, a tendency toward superficial spread without invasion, and good prognosis with prolonged survival. WDPM occurs primarily in the peritoneum of women, but also rarely in the pleura. We here report a case of 48-year-old woman who developed WDPM in the pleura with no history of asbestos exposure. Tumors were multifocal and widespread with a velvety appearance on the surface of parietal and visceral pleurae resected by extrapleural pneumonectomy (EPP). Tumors showed papillary structures with fibrovascular cores and lined by epithelioid cells. Immunohistochemically, these epithelioid tumor cells were positive for epithelial membrane antigen (EMA), a marker of malignant mesothelioma, with more than 50% positive for p53. Tumor cells microinvaded into subpleural parenchyma of the lung and minimally spread to adipose tissues of the mediastinal lesion. In addition, tumor cells invaded into the chest wall with a trabecular or glandular architecture. Based on these findings, this case is pathologically considered as WDPM of the pleura with malignant potential.

Circulating tumor cell as a diagnostic marker in primary lung cancer.

PURPOSE: To investigate the diagnostic performance of circulating tumor cells (CTC) in discrimination between primary lung cancer and nonmalignant diseases as well as in prediction of distant metastasis. PATIENTS AND METHODS: We prospectively evaluated CTCs in 7.5-mL samples of peripheral blood sampled from patients with a suspicion or a diagnosis of primary lung cancer. A semiautomated system was used to capture CTCs with an antibody against epithelial cell adhesion molecule. RESULTS: Of 150 eligible patients, 25 were finally diagnosed as having nonmalignant disease, and 125 were diagnosed as having primary lung cancer with (n = 31) or without (n = 94) distant metastasis. CTCs were detected in 30.6% of lung cancer patients and in 12.0% of nonmalignant patients. CTC count was significantly higher in lung cancer patients than in nonmalignant patients, but a receiver operating characteristic (ROC) curve analysis showed an insufficient capability of the CTC test in discrimination between lung cancer and nonmalignant diseases with an area under ROC curve of 0.598 (95% confidence interval, 0.488-0.708; P = 0.122). Among lung cancer patients, CTC count significantly increased along with tumor progression, especially with development of distant metastasis. The area under ROC curve for CTC count in prediction of distant metastasis was 0.783 (95% confidence interval, 0.679-0.886; P < 0.001). When patients with one or more CTCs were judged as having metastatic disease, sensitivity and specificity of the CTC test were 71.0% and 83.0%, respectively. CONCLUSIONS: CTC is a useful surrogate marker of distant metastasis in primary lung cancer.

Circulating tumor cells in pulmonary venous blood of primary lung cancer patients.

BACKGROUND: Circulating tumor cells in peripheral blood (CTC) is a potential surrogate of distant metastasis, which is the critical factor influencing decision making regarding therapy and prognosis of primary lung cancer patients. After our preliminary study showing that CTCs were detected in peripheral blood in 29.4% of resectable lung cancer patients, we conducted a prospective study on CTC in pulmonary vein (PV) blood because tumor cells apart from the primary tumor may circulate after passing through the drainage PV. METHODS: A total of 30 consecutive lung cancer patients who underwent thoracotomy were included. The CTCs in peripheral blood and in PV blood from the primary tumor site were quantitatively examined with the CellSearch system, and the numbers of CTCs per 7.5 mL peripheral and PV blood in each patient were represented as periCTC count and pvCTC count, respectively. RESULTS: Circulating tumor cell was detected in peripheral blood in 5 patients (16.7%; the periCTC count was 1 in 2 patients; and 2, 3, and 16 in 1 patient each), and the incidence of positive periCTC was higher in squamous carcinoma patients than in adenocarcinoma patients (p = 0.028). Circulating tumor cell was detected in PV blood in most patients (29 of 30, 96.7%), and the mean and median pvCTC counts were 1,195 and 81, respectively (range, 0 to 10,034). There was no significant correlation between pvCTC count and any other patient characteristic, including periCTC count. CONCLUSIONS: In resectable lung cancer, CTC was positive in peripheral blood of some patients and in PV blood of most patients. A long-term follow-up study to clarify the clinical significance of pvCTC status is warranted.

Perivascular epithelioid cell tumor of the rib.

We present a rare case of perivascular epithelioid cell tumor (PEComa) in the right 6th rib of a 28-year-old man. A plain computed tomography scan showed a round osteolytic lesion in the right 6th rib. The resected tissue contained a globular-shaped, soft tumor. Histologically, the tumor was rich in vasculature and exclusively composed of perivascular epithelioid cells with clear cytoplasm. Immunohistochemically, the tumor expressed diffusely a melanocyte marker, human melanoma black-45, and focally a myogenic marker, alpha-smooth muscle actin, but not an epithelial marker, AE1/AE3. Fontana-Masson-positive melanin pigments were present and c-kit receptor tyrosine kinase (CD117), involved in the development of melanocytes but not myogenic cells, was expressed in tumor cells. These findings indicate that the tumor is PEComa with some differentiation into melanocytes. Notably, owing to the unique location of the occurrence, the tumor occupied bone marrow tissues of the rib, resulting that the tumor has the potential for hematogenous metastasis. In spite of the lack of cells with severe atypia, necrosis, and numerous mitoses, tumor cells invaded into surrounding tissues and overexpressed cyclin D1. To the best of our knowledge, this is the first case report of PEComa arising from the rib with the signs of malignant potential.