Surgical diagnosis and treatment of a solitary lung nodule of IgG4-related disease, mimicking primary lung carcinoma or metastatic lung tumour: A rare case.

INTRODUCTION: IgG4-related disease is a poorly understood immune disorder. Its features include tumour-like swelling of involved organs, lymphoplasmacytic infiltrate with IgG4 positive plasma cells. IgG4-related lung disease can manifest radiologically as various types of pulmonary abnormalities, including mass-like lesions and pleural effusion, and it may mimic malignant disease. PRESENTATION OF CASE: A 76-year-old man was found to have a 4-mm ground glass opacity in the left lower lobe of the lung on follow-up chest CT after surgery for colon carcinoma. This lesion gradually became consolidated and enlarged to 9 mm over about three years. We performed a video-assisted left basal segmentectomy for the purposes of both diagnosis and treatment. Pathological examination revealed lymphoplasmacytic infiltration, mainly with IgG4-positive plasma cells. DISCUSSION: A major characteristic of IgG4-related lung disease is multiple, small, bilateral, lung nodules and solid nodules reportedly being detected in almost all patients. However, solitary nodules are rare, being present in only 14 %. Moreover, this case shows extremely rare radiological findings in which a ground-glass opacity had gradually morphed into a solid nodule. It is difficult to differentiate IgG4-related lung nodules from other lung diseases, such as primary or metastatic lung tumours, standard interstitial pneumonia, organizing pneumonia. CONCLUSION: We have here presented a rare case of IgG4-related lung disease with a 3-year course, including detailed radiological findings. Surgery is very useful for both diagnosis and treatment of a small, solitary, deeply located, pulmonary nodule of IgG4-related lung disease.

Hypothyroidism With ACTH Deficiency During Pembrolizumab Therapy for Lung Cancer: Case Report and Literature Review.

BACKGROUND/AIM: Immune-checkpoint inhibitors have recently shown great promise in treating various cancers, but often cause immune-related adverse events (irAEs). Simultaneous drug-induced hypothyroidism and isolated adrenocorticotropic hormone (ACTH) deficiency are rare irAEs. This combination of irAEs is associated with paradoxical endocrine dysfunction characterized by large amounts of thyroid-stimulating hormone (TSH) and small amounts of ACTH in the anterior lobe of the pituitary. We herein report a case of hypothyroidism with isolated ACTH deficiency during pembrolizumab therapy for recurrent lung cancer. CASE REPORT: Our patient was a 66-year-old man with recurrence of squamous cell lung carcinoma. Four months after chemotherapy that included pembrolizumab, the patient presented with general fatigue and laboratory tests showed high concentrations of TSH with low concentrations of free-T4. He was diagnosed with hypothyroidism and levothyroxine was prescribed. His ACTH concentration was found to be low 1 week later when he developed an acute adrenal crisis with associated hyponatraemia. We then changed his diagnosis to concurrent hypothyroidism with isolated ACTH deficiency. His condition improved after 3 weeks of administration of cortisol. CONCLUSION: It is difficult to diagnose a concurrent paradoxical endocrine disorder, such as hypothyroidism with isolated ACTH deficiency, as in the present case. Physicians should pay attention to symptoms and laboratory data to identify various types of endocrine disorders as irAEs.

Surgical treatment of Bochodalek hernia incarcerated into the extra-pleural space: A rare case report.

INTRODUCTION: Bochdalek hernias are a type of diaphragm hernia. Almost all occur in the neonatal period, only 5% of these hernias occurring in adults. We here present a rare case of adult Bochdalek hernia incarcerated in the extra-pleural space. PRESENTATION OF CASE: An asymptomatic 51-year-old man was admitted to our hospital for a detailed examination after an abnormality had been detected on a chest radiograph. Chest computed tomography (CT) examination revealed findings consistent with a left Bochdalek hernia, which we repaied surgically. Intraoperatively, retroperitoneal fatty tissue was found to be incarcerated in the extra-pleural space. Thus, surgical repair required dissection of the parietal pleura and excision of the incarcerated fatty tissues. DISCUSSION: The incarceration of the Bochdalek hernia in the extra-pleural space could not be identified on a preoperative chest CT examination. To the best of our knowledge, no reports of incarceration of a Bochdalek hernia in the extra-pleural space have been published; thus, this phenomenon is extremely rare. CONCLUSION: Surgical treatment of a Bochdalek hernia incarcerated in the extra-pleural space requires dissection of the parietal pleura and repair via a transthoracic approach.

18F-FDG uptake in PET/CT is a potential predictive biomarker of response to anti-PD-1 antibody therapy in non-small cell lung cancer.

To examine the association between 18F-fluorodeoxyglucose (18F-FDG) uptake in positron emission tomography/computed tomography (PET/CT) and the response to anti-programmed cell death-1 (PD-1) monoclonal antibody therapy in non-small cell lung cancer (NSCLC) patients, 89 patients with advanced or recurrent NSCLC were retrospectively analysed. Maximum standardized uptake value (SUVmax) in 18F-FDG PET/CT and the response to anti-PD-1 antibodies were recorded. A cut-off value of SUVmax was determined by receiver operating characteristic curve analysis for patient stratification. Among the 89 patients evaluated, 24 were classified as responders (all partial response), and 65 as non-responders. The average SUVmax of the responders was 15.60 (range, 6.44-51.10), which was significantly higher than that of the non-responders (11.61; range, 2.13-32.75; P = 0.0168, Student's t-test). The cut-off SUVmax value selected for stratification was 11.16 (sensitivity and specificity, 0.792 and 0.585, respectively). The response rate of patients with SUVmax value ≥ 11.16 (41.3% [19/46]) was significantly higher than that of patients with SUVmax < 11.16 (11.6% [5/43], P = 0.0012, Chi-squared test). The SUVmax in 18F-FDG PET/CT is a potential predictive marker of response to anti-PD-1 antibody therapy in NSCLC patients. Further prospective studies of large populations are necessary to validate these results.

Pulmonary metastasis presenting as a ground glass opacity-like lesion with a thin-walled cavity: A case report.

INTRODUCTION: Most of pulmonary metastases present as well-defined solid and round nodules. Here we report a case of a pulmonary metastasis presenting as a ground glass opacity (GGO)-like lesion with a thin-walled cavity and lymph node metastasis of tongue cancer. CASE PRESENTAION: A 22-year-old man was referred to our department for surgical diagnosis and treatment for a GGO-like pulmonary nodule with a thin-walled cavity in the right lower lobe. He had a history of surgical resection for tongue cancer. The size of the GGO-like lesion with a thin-walled cavity in the center gradually increased. A right lower lobectomy and hilar lymphadenectomy were performed. Postoperative pathology revealed the lesion as pulmonary metastasis and hilar lymph node metastasis of tongue cancer. DISCUSSION: Our case report of pulmonary metastasis of tongue cancer is rare from the viewpoint of pulmonary GGO-like lesions with a following thin-walled cavity and hilar lymph node metastasis. The positron emission tomography/computed tomography (PET/CT) examination was useful to show right hilar lymph node metastasis. CONCLUSION: It is important to make a differential diagnosis of from the pulmonary nodule in case of a GGO-like lesion with a thin-walled cavity.

Association between peripheral blood markers and immune-related factors on tumor cells in patients with resected primary lung adenocarcinoma.

We sought to identify peripheral blood markers associated with two immune-related factors-programmed cell death-ligand-2 (PD-L2) and indoleamine 2,3-dioxygenase-1 (IDO1)-that are expressed on tumor cells in primary lung adenocarcinoma (AD) specimens. We randomly selected 448 patients (70%) from 640 consecutive patients with resected stage I-III primary lung AD, who had been treated at that point with surgery alone. Expression of PD-L2 and IDO1 in these patients was assessed by immunohistochemistry, and evaluated with respect to peripheral blood markers measured before surgery, including white blood cells, absolute neutrophil count, absolute lymphocyte count, absolute monocyte count (AMC), absolute eosinophil count (AEC), serum C-reactive protein, and serum lactate dehydrogenase levels. Membrane PD-L2 expression and cytoplasmic IDO1 expression were defined by tumor proportion score (TPS); samples with TPS < 1% were considered negative. Logistic regression models were used to identify variables associated with the immune-related factors. Advanced stage (P = 0.0090), higher AMC (P = 0.0195), and higher AEC (P = 0.0015) were independent predictors of IDO1 expression. PD-L2 expression was not associated with any tested peripheral blood markers. Peripheral blood markers, especially AMC and AEC, could potential predict IDO1 expression in lung AD. This study should be replicated in another cohort; further efforts to explore other biomarkers that predict PD-L2 or IDO1 expression are also warranted.

Clinical and Prognostic Significance of the Epithelial-Mesenchymal Transition in Stage IA Lung Adenocarcinoma: A Propensity Score-Matched Analysis.

BACKGROUND: The epithelial-mesenchymal transition (EMT) describes the process through which cells lose epithelial characteristics and gain a mesenchymal phenotype. The EMT contributes to tumor invasion and cancer progression, and is associated with metastasis and poor survival of patients with non-small-cell lung cancer. However, little is known about the relationships between the EMT and the clinicopathologic characteristics of patients with stage IA lung adenocarcinoma. PATIENTS AND METHODS: We conducted immunohistochemical analysis of the expression of the EMT markers E-cadherin and vimentin of specimens acquired from 183 consecutive patients with stage IA lung adenocarcinoma. The clinicopathologic significance of the association of the EMT status with E-cadherin and vimentin expression was analyzed after propensity score matching. RESULTS: E-cadherin and vimentin were detected in 68.3% and 18.6% of stage IA lung adenocarcinomas, respectively. The presence of cells with EMT conversion was associated with older patient age. A propensity score-matched cohort (128 patients) was used for further analyses. Computed tomography revealed that tumors with EMT conversion showed solid-dominant nodules compared to those without conversion. Survival analysis after propensity score matching showed that the EMT correlated with poor disease-free survival (hazard ratio = 2.57, P = .0451) and overall survival (hazard ratio = 4.23, P = .0471). Multivariate analysis revealed that the EMT was an independent predictor of shorter disease-free survival. CONCLUSION: The EMT was a significant predictor of poor prognosis of patients with stage IA lung adenocarcinoma. The EMT status may serve as an indicator for administering adjuvant therapy.

The association and prognostic impact of enhancer of zeste homologue 2 expression and epithelial-mesenchymal transition in resected lung adenocarcinoma.

OBJECTIVES: Epithelial-mesenchymal transition (EMT) and the histone methyltransferase Enhancer of Zeste Homologue 2 (EZH2) are important regulators of lung cancer progression and metastasis. Although recent studies support the correlation between EZH2 expression and EMT, no reports have investigated their association using immunohistochemistry or explored their prognostic impact on lung adenocarcinoma. The aim of this study was to elucidate the association between EZH2 and EMT, and their prognostic significance. METHODS: EZH2 and the EMT markers E-cadherin and Vimentin were examined by IHC in lung adenocarcinoma specimens that were resected from 2003-2012. Associations between EZH2 and EMT markers and their correlations with survival were analyzed. RESULTS: We enrolled 350 patients, approximately 70% of whom were diagnosed as pathological stage I. The rates of positive E-cadherin, Vimentin, and EZH2 expression were 60.3%, 21.4%, and 52.0%, respectively. There was a significant positive correlation between EZH2 and Vimentin expression (p = 0.008), and EZH2 scores were higher in the Mesenchymal group (p = 0.030). In multivariate analysis, EZH2 was an independent predictor of Vimentin expression, and vice versa. EMT and EZH2 overexpression were significantly correlated with poor disease-free and overall survival. Furthermore, the Epithelial group with high EZH2 expression had significantly worse disease-free and overall survival. Positive staining for EMT markers was unfavorable regarding disease-free survival among patients with low EZH2 expression. CONCLUSIONS: EMT and high EZH2 expression were associated with poor NSCLC prognoses. Vimentin is a key factor linking EMT and EZH2 in lung adenocarcinoma.

Association of Low Body Mass Index With Poor Clinical Outcomes After Resection of Non-small Cell Lung Cancer.

BACKGROUND/AIM: This study was performed to evaluate the influence of the body mass index (BMI) on disease-free survival and overall survival (DFS and OS) in patients with resected non-small cell lung cancer (NSCLC). PATIENTS AND METHODS: Overall, 546 of 780 (70%) patients with stage I to III NSCLC who underwent surgical resection were randomly selected. The patients were subdivided into three groups: low BMI (<18.5 kg/m2), normal BMI (18.5 to <25.0 kg/m2), and high BMI (≥25.0 kg/m2). Cox proportional hazards regression analyses were performed to identify variables associated with survival. RESULTS: In all patients, a low BMI was an independent prognostic factor for both DFS and OS (p=0.0175 and p=0.0134, respectively). In patients with stage I, a low BMI was also an independent prognostic factor for both DFS and OS (p=0.0066 and p<0.0001, respectively). CONCLUSION: A low BMI was an independent prognostic factor after surgical resection of stage I NSCLC. Molecular targeted therapies, such as epidermal growth factor receptor inhibitors, anaplastic lymphoma kinase-tyrosine kinase inhibitors, and immune checkpoint inhibitors targeting the programmed cell death-1/programmed cell death-ligand 1 (PD-L1) pathway have greatly improved the clinical course for patients with non-small cell lung cancer (NSCLC), especially advanced-stage NSCLC (1-7). However, lung cancer remains the leading cause of cancer-related death worldwide (8). Even in patients with stage I to IIIA NSCLC, the clinical course is unsatisfactory despite the fact that surgical resection is the main treatment option (9). Therefore, it is important to identify useful, simple, and inexpensive prognostic markers in patients with resectable NSCLC.

A Clinicopathological and Prognostic Analysis of PD-L2 Expression in Surgically Resected Primary Lung Squamous Cell Carcinoma.

BACKGROUND: Immunotherapy targeting programmed cell death-1 (PD-1) and programmed death-ligand 1 (PD-L1) has shown dramatic therapeutic effects for lung squamous cell carcinoma (SCC), and PD-L1 expression has been shown not only to be a predictive biomarker for response to immunotherapy but also a prognostic factor for lung SCC. However, the clinical significance of programmed death-ligand 2 (PD-L2), another PD-1 ligand, remains unclear. Therefore, we analyzed PD-L2 expression by immunohistochemistry in surgically resected primary lung SCC. PATIENTS AND METHODS: PD-L1 and PD-L2 expression on tumor cells were analyzed in 211 primary lung SCC specimens by immunohistochemistry. Additionally, numbers of CD3+, CD4+, and CD8+ tumor-infiltrating lymphocytes were also examined. RESULTS: The rates of positive PD-L2 expression were 77.3% and 67.3% using 5% and 10% cut-off values, respectively. Low PD-L2 expression on tumor cells was statistically associated with histological type (non-keratinizing/keratinizing) and lymphatic invasion. PD-L2-positive patients had significantly longer postoperative survival time (log-rank test; p = 0.0170 at 5% cut-off and p = 0.0500 at 10% cut-off). Furthermore, survival analysis according to PD-L1 and PD-L2 expression revealed that PD-L1-positive and PD-L2-negative patients had the most unfavorable prognosis. CONCLUSIONS: PD-L2 protein expression was associated with prognosis in primary lung SCC patients. PD-L2 expression might be a potential biomarker for response to PD-1/PD-L1-targeted immunotherapy, which should be investigated in future studies.

Co-expression of IDO1 and PD-L1 in lung squamous cell carcinoma: Potential targets of novel combination therapy.

OBJECTIVES: Combination therapy with an inhibitor of indoleamine 2, 3-dioxygenase 1 (IDO1) and an agent targeting programmed cell death-1 (PD-1)/programmed cell death-ligand 1 (PD-L1) is expected to be a novel and effective treatment option for various solid tumors including non-small cell lung cancer (NSCLC). Therefore, it is important to elucidate the clinical and pathological features of tumors with IDO1/PD-L1 co-expression and the association between IDO1/PD-L1 co-expression and efficacy of combination therapy in NSCLC patients. In this study, we examined the prognostic impact of IDO1/PD-L1 co-expression and its relationship with tumor-infiltrating lymphocytes (TILs) in primary lung squamous cell carcinoma (SCC). MATERIALS AND METHODS: The expression levels of IDO1, PD-L1, Ki-67, cluster of differentiation 3 (CD3), CD4, and CD8 in 202 patients with surgically resected primary lung SCC were evaluated by immunohistochemistry. RESULTS: Among 202 patients, 176 (87.1%) were positive for IDO1 expression, 106 (52.5%) were positive for PD-L1 expression, and 99 (49.0%) showed co-expression of IDO1/PD-L1 proteins. Fisher's exact test showed a significant association between IDO1 and PD-L1 tumor proportion scores (P = 0.0011). Kaplan-Meier curve showed that PD-L1 alone and co-expression of IDO1 and PD-L1 were significantly associated with shorter overall survival, but IDO1 alone was not (log rank test: P = 0.0122, P = 0.0303 and P = 0.5168, respectively). The Ki-67 labeling index was significantly higher in patients with co-expression of IDO1 and PD-L1 than in patients without co-expression (Student's t-test: P = 0.0005). Moreover, IDO1/PD-L1 co-expression was significantly associated with high CD3, CD4, and CD8 expression (Fisher's exact test: P = 0.0033, P = 0.0003, and P < 0.0001, respectively). CONCLUSIONS: IDO1 expression correlated to PD-L1 expression, and co-expression of IDO1 and PD-L1 may be important targets for immunotherapy in lung SCC.

A rare case of gradual enlargement of a multifocal myelolipoma of the posterior mediastinum for 12 years after surgical resection of an adrenal myelolipoma.

INTRODUCTION: A myelolipoma is a rare benign tumor that is composed of adipose tissue and hematopoietic elements. Myelolipomas most commonly occur in the unilateral adrenal gland. Posterior mediastinal myelolipomas are extremely rare. We herein present a rare case of a multifocal myelolipoma of the mediastinum that gradually enlarged over a 12-year period after surgical resection of an adrenal myelolipoma. This is the first report of multifocal myelolipomas of the posterior mediastinum and adrenal gland. PRESENTATION OF CASE: A posterior mediastinal tumor was incidentally found by chest X-ray and computed tomography (CT) examination of a 74-year-old woman. The patient had a medical history of resection of a myelolipoma of the left adrenal gland 12 years earlier. We performed tumor extirpation under video-assisted thoracic surgery (VATS). The size of the tumor was 4.5 cm, and the postoperative diagnosis was a myelolipoma. DISCUSSION: Posterior mediastinal myelolipomas are extremely rare, and only 39 cases of mediastinal myelolipoma have been reported to date. No reports have described a multifocal myelipoma of mediastinal myelolipoma. To our knowledge, this is the first report of multifocal myelipomas of the adrenal gland and posterior mediastinum. CONCLUSION: A differential diagnosis of myelolipoma of the posterior mediastinum is important in patients with a history of myelolipoma of the adrenal gland.

Radiological Features of IDO1+/PDL1+ Lung Adenocarcinoma: A Retrospective Single-institution Study.

AIM: A combination of immune-checkpoint inhibitors that target the programmed cell death 1 (PD1)/programmed cell-death ligand 1 (PDL1) pathway and indoleamine 2,3-dioxygenase 1 (IDO1) is a promising treatment for non-small-cell lung cancer. Herein, we investigated clinical features of IDO1+/PDL1+ primary lung adenocarcinoma. MATERIALS AND METHODS: IDO1 and PDL1 expression in 388 resected primary lung adenocarcinoma samples was evaluated using immunohistochemistry, and the radiological features of patients with IDO1+/PDL1+ lung adenocarcinoma were analyzed. RESULTS: Of 388 specimens, 229 (59.0%) were IDO1+, 131 (33.8%) were PDL1+, and 109 (28.1%) were IDO1+/PDL1+ In multivariate analysis, vascular convergence and the absence of surrounding ground glass opacity were significantly associated with IDO1+/PDL1+ tumors. Fisher's exact test showed high consolidation/tumor ratio was also significantly associated with IDO1+/PDL1+ tumors. Moreover, maximum standardized uptake in 18F-fluorodeoxyglucose positron-emission tomography/computed tomography was significantly higher in patients with IDO1+/PDL1+ tumors than in those with IDO1- or PDL1- tumors. CONCLUSION: IDO1/PDL1 co-expression was significantly related to radiological invasiveness and malignancy in lung adenocarcinoma. This study may help select patients likely to benefit from combination therapy using immune-checkpoint inhibitors.

A rare case of an intercostal lung herniation with fractures of the fifth and sixth ribs after thoracic surgery.

INTRODUCTION: Lung herniation is a rare condition defined as a protrusion of the pleural-covered lung parenchyma through an abnormal defect or weakness in the thoracic wall. Postoperative lung herniation is reported to result from a preceding operation with inadequate closure of the chest wall. PRESENTATION OF CASE: A 77-year-old woman was admitted to our hospital for treatment of hemoptysis and nausea. One year previously, she had undergone wedge resection of the right lower lobe (S6) for treatment of primary lung adenocarcinoma. Upon admission, chest radiograph and chest computed tomography showed a right lung herniation through the fifth enlarged intercostal space with right fifth and sixth rib fractures. She underwent surgical closure of the intercostal hernia using synthetic materials with fixation of the fifth and sixth ribs. The patient had developed no recurrence 9 months after surgical repair. DISCUSSION: In the present case, adequate closure of the right pleural cavity was ensured by fixation of both fifth and sixth ribs during the preceding video-assisted thoracic surgery for the primary lung carcinoma. Our patient may have had some exacerbation factors for lung herniation, increased intrathoracic pressure, attenuation of chest wall by prolonged coughing and rib fracture, and high abdominal pressure due to her hunched-over posture. CONCLUDION: It is important to know some exacerbation factors for postoperative intercostal lung herniation. Addition of monofirament-suture fixation of the ribs to patch repair is very effective for lung herniation repair in patients with concurrent lung herniation and rib fractures.

A case report of successful diagnosis of a pulmonary nodule by a survey of oncogenic mutations; primary lung carcinoma or pulmonary metastasis?

INTRODUCTION: The number of patients diagnosed with solid carcinomas is increasing, and the most common site of metastasis is the lungs. It is often difficult to make a differential diagnosis between primary lung carcinoma and metastatic lung tumor in using histological examination and by determining their immunohistological status. PRESENTATION: A 64-years-old man presented with dyspnea with chest computed tomography (CT) findings of a pulmonary tumor, and afterwards suffered from a sudden bowel hemorrhaged due to colorectal carcinoma. The histological diagnosis of a pulmonary tumor was poorly differentiated adenocarcinoma. Both Thyroid transcription factor-1 (TTF-1) and Cytokeratin20 (CK20) were immunohistologically negative. Of the some oncogenic mutations investigated, a neuroblastoma RAS viral oncogen homolog (NRAS) codon13 G13D mutation was detected in both the colorectal carcinoma and the pulmonary tumor tissue samples. Based on the result, the pulmonary tumor was diagnosed as a metastasis derived from colorectal carcinoma. DISCUSSION: Recently, examination of the oncogenes of solid carcinomas has been clinically investigated in primary lung caricnoma and in colorectal carcinomas. The clinical advantage of the oncogenic mutation survey is to identify the site, and the type, of amino acid change in detail. This case is a rare successful case of a survey of the oncogenes for giving a differential diagnosis. CONCLUSION: A survey of the oncogenic genes is very useful to make a differential diagnosis between primary lung carcinoma and metastatic lung tumor.

Prognostic Significance of Expression of the Epithelial-Mesenchymal Transition-Related Factor Brachyury in Intrathoracic Lymphatic Spread of Non-Small Cell Lung Cancer.

BACKGROUND: Brachyury is a transcriptional regulator that plays important roles in epithelial mesenchymal transition (EMT) during development and has been reported to be essential for mesoderm formation in the early human embryo. We investigated Brachyury protein expression in hilar and mediastinal metastatic lymph nodes of non-small cell lung cancer patients and the prognostic significance of Brachyury expression at metastatic sites. METHODS: Expression of Brachyury in 115 surgically resected primary lung cancer and corresponding metastatic lymph node samples was evaluated by immunohistochemical staining. The relationships between Brachyury protein expression and the patient's clinicopathological factors and prognosis were analyzed. RESULTS: Brachyury expression in metastatic lymph nodes was significantly higher than that in the primary tumor (p = 0.012). Patients with high Brachyury expression in the metastatic lymph nodes had significantly poor prognoses (p = 0.0236) compared with patients with low expression. In addition, patients with larger differences in Brachyury expression between metastatic lymph nodes and the primary tumor had significantly poorer prognoses compared with patients with smaller differences (p = 0.0146). The Brachyury protein expression level in metastatic lymph nodes was significantly associated with the protein expression levels of other EMT-related factors (E-cadherin [inverse association], p = 0.0265; Slug, p = 0.029; and interleukin-8, p = 0.0135). CONCLUSIONS: High expression of Brachyury protein in metastatic carcinoma cells in the intrathoracic lymph nodes was associated with poor prognosis of lung cancer patients. Increased Brachyury expression during the metastatic process may confer further potential for invasion and metastasis of cancer cells.

Complete resection of unicentric Castleman disease in the superior mediastinum: A case report.

INTRODUCTION: Castleman disease (CD) is a rare benign lymphoproliferative disorder characterized by benign lymph node hyperplasia in a single site (unicentric CD [UCD]) or in multiple sites (multicentric CD [MCD]). Patients with UCD are usually asymptomatic; however, those with MCD usually develop fever, weight loss, and peripheral lymphadenopathy. CASE PRESENTATION: We describe a case of surgically resected UCD in the superior mediastinum in which the involved lymph node was surrounded by important vessels and trachea, necessitating a median sternotomy for complete resection of the tumor. DISCUSSION: Preoperative diagnosis of UCD in the thorax is very difficult, and surgical resection or excision is necessary. Complete resection is recommended for UCD because it is curative and has a 5-year survival rate of 100%. CONCLUDION: UCD should be included in the differential diagnosis of asymptomatic mediastinal tumors. Surgical resection or excision is preferred to ensure an accurate diagnosis and appropriate treatment if malignant disease cannot otherwise be ruled out.

A rare case of human pulmonary dirofilariasis with a growing pulmonary nodule after migrating infiltration shadows, mimicking primary lung carcinoma.

INTRODUCTION: Pulmonary dirofilariasis is a rare pulmonary parasitic infection by the nematode Dirofilaria immitis. It is characterized by an asymptomatic pulmonary nodule usually seen on chest X-ray. The differential diagnosis of pulmonary dirofilariasis includes other pulmonary diseases, primary lung carcinoma and metastatic lung tumor. CASE PRESENTATION: Pulmonary dirofilariasis was diagnosed in a woman who presented with interstitial pneumonia. Growth of the pulmonary nodule was detected subsequent to hemoptysis. The histological diagnosis was made based on a wedge resection performed under video-associated thoracic surgery (VATS). CONCLUSION: Pulmonary dirofilariasis often varies in its clinical course. The diagnosis is best made using wedge resection under VATS.

A rare case report of rib hemangioma mimicking a malignant bone tumor or metastatic tumor.

Hemangioma of the rib is a rare benign vascular tumor. This benign disease induces osteolytic changes, and must be distinguished from a malignant bone tumor or metastatic tumor. Definitive diagnosis is achieved by excision biopsy or histological examination after surgical resection in many cases. We here in present a rare case of hemangioma of the rib.

Four-year natural clinical course of pulmonary epithelioid hemangioendothelioma without therapy.

Pulmonary epithelial hemangioendothelioma is a rare low to intermediate malignant vascular tumor originating from vascular endothelial cells. The therapy for this disease, if possible, is surgical resection. However, there is no standard treatment for patients with multiple unresectable lesions. We present the case of a 42-year-old woman treated with a natural clinical course of hemangioendothelioma for four years without therapy. The nodules have increased in number and size extremely slowly, and the patient is alive and asymptomatic four years after diagnosis.