Primary pulmonary meningiomas: report of two cases and review of the literature.

BACKGROUND: Meningiomas rarely occur outside the skull, and primary pulmonary meningiomas (PPMs) are more rare. Only a few cases have been reported in the literature. The clinicopathological characteristics are not clear and it is easy to be misdiagnosed, so it is very important to master its diagnosis and differential diagnosis. METHODS: We report two women with primary pulmonary meningioma. At the time of physical examination, the small solitary pulmonary nodules were detected on chest radiograph, and wedge resection was performed by Video-assisted Thoracoscope Surgery(VATS), and histologic evaluation showed that the lesions were benign PPMs. The clinicopathological features, immunophenotype and differential diagnosis of PPMs were analyzed, with a review of the cases published in the literature. RESULTS: The study group comprised of 40 patients, 14 males and 26 females. The median age was 56.5 years (range 18-108). Thirty patients who underwent routine screening studies were asymptomatic but had a pulmonary nodule detected on chest X-ray. Nine patients had respiratory symptoms. Only 1 patient had non-specific symptoms. Most of the PPMs were benign, only 3 cases were malignant. Benign PPMs ranged from 0.6 cm to 6 cm in diameter (median 2 cm). The 3 malignant PPMs were 5 cm, 6.5 cm and 15 cm in diameter. The prognosis of benign PPM resection is good, with almost no recurrence or metastasis. But the two of three malignant PPMs relapsed. CONCLUSIONS: PPM is very rare. It needs to be diagnosed by combining histology and immunohistochemistry. Diseases that need to be identified include spindle cell mesothelioma, spindle cell thymoma, spindle cell carcinoma, metastatic tumor, etc.

Differential diagnosis of a rare papillary tumor and mucinous adenocarcinoma.

Ciliated muconodular papillary tumors are characterized as rare papillary tumors of the peripheral lung, and involve ciliated, goblet, and basal cell proliferation with mucin secretion. We report the case of a 76-year-old woman who had an irregular solid nodule in the lung on chest computed tomography during a health screening. A wedge resection was performed. Although the intraoperative cytological diagnosis was mucinous adenocarcinoma, the final histological diagnosis was ciliated muconodular papillary tumor. The postoperative course was uneventful, with no recurrence at 24 months after surgery. Cytological diagnosis of ciliated muconodular papillary tumor can be difficult because of its similarity to mucinous adenocarcinoma.

[Localizating and Extracting Small Peripheral Nodules of Lung with Simulating 
Radiaotherapy Combining Methylene Blue Staining].

BACKGROUND: With the extensively application of HRCT (high resolution CT) and the popularization of early lung cancer screening, the proportion of small nodullar lung cancer to be operated increases rapidly. Identifying the focus lesions quickly and accurately in operation has shown to be a challenge. We carried out this research trying to make use of and evaluate a new method that localizaes and extracts small peripheral pulmonary nodules by way of simulating radiaotherapy combining methylene blue staining. METHODS: From February 2012 to January 2015, 97 patients with 100 peripheral pulmonary nodules ≤10 mm in size were simulated puncturing using a radiotherapy planning. When the anaesthesia came into use, methylene blue dye was injected to the virtually identified point corresponding to the surface point, according to the angle and depth previously computed by the radiotherapy planning. The video-assisted thoracoscopic surgery (VATS) wedge resections of the marked lesions were undertaken and the specimens were sent for frozen pathologic examination. The interval time from anesthesia-completing to puncture and injection, The interval time from methylene blue injection to identifying the stained area and the distances between the centre point of the stains and edge of coloured lesion were recorded. RESULTS: Our preoperative localization procedure was successful in 96 of 100 (96%) nodules. The interval time from anesthesia-completing to puncture and injection of methylene blue were (4.85±1.25) min. The interval time from methylene blue injection to identifying the stained area was (16.36±2.36) min. The distances between the centre point of the stains and edge of coloured lesion were (4.78±2.51) mm. No complication was observed in all participants. CONCLUSIONS: The new method of locating peripheral pulmonary nodules by simulating simulating radiaotherapy combining methylene blue staining has a high success rate and no complication for localizing small peripheral pulmonary lesions, avoiding the fear and pain of the patients untaken puncture without anaesthesia reducing radial damage.

Ciliated muconodular papillary tumor: a solitary peripheral lung nodule in a teenage girl.

Papillary tumors of the peripheral lung containing ciliated cells and extracellular mucin include solitary peripheral ciliated glandular papilloma, ciliated muconodular papillary tumor, and well-differentiated papillary adenocarcinoma with cilia formation. We report the case of a 19-year-old woman who was a nonsmoker and presented with an incidental small peripheral lung nodule. The resection specimen showed a soft grayish nodule. Histologic examination further revealed a relatively circumscribed mucinous nodule featuring a tubulopapillary tumor composed of ciliated columnar cells and goblet cells, accompanied with abundant extracellular mucin. No lepidic growth pattern was evident. The tumor cells were immunoreactive for cytokeratin 7, thyroid transcription factor-1, and carcinoembryonic antigen, whereas p63 and cytokeratin 5/6 highlighted the presence of basal cells. Next-generation sequencing did not identify any genetic alterations in targeted regions and mutational hotspots of a panel of 22 genes commonly implicated in lung and colon cancers. Taken together, our case was most likely a ciliated muconodular papillary tumor.

An unusual tumour of the lung.

We report a case of a 51-year-old woman with a solitary mast cell tumour of the lung, a rare neoplasm with only three previously-reported cases reported in the literature. Unlike previous cases, the tumour in the present case was bulky, measuring 14 cm in diameter and budding into the segmental bronchus. Histologically, it showed proliferation of typical metachromatic mast cells intermingled with undifferentiated cells with a ratio of 3:1. The neoplastic mast cells stained strongly with tryptase, CD117, CD68 and CD45, CD14 and CD33; whereas the undifferentiated cells lacked all these markers and expressed EMA and cytokeratin. Histological examination of bone marrow and laboratory data were unremarkable. To our knowledge, this is the fourth case of solitary extracutaneous mastocytoma of the lung. The differentiating features of this neoplasm and a review of literature are presented.

Solitary endobronchial papillomas with false impression of malignant transformation: report of two cases and review of the literature.

Solitary endobronchial papillomas (SEPs) are rare benign tumors of the lung, seldom transform to malignancy. This tumor had been reported occasionally manifest like carcinomas histologically. Herein we report 2 cases of SEPs; one is a squamous cell papilloma providing a false impression of interstitial micro-invasion. The other is a mixed squamous cell and glandular papilloma with massive lipid pneumonia gross appearance, and focally resembles adenocarcinoma with lepidic-like pattern on histological examination. A review of associated literatures was provided.

A rare case of pulmonary sclerosing hemagioma with lymph node metastasis and review of the literature.

Pulmonary sclerosing hemagioma (SH) is an uncommon tumor with malignance potential. Clinically this disease is regarded as benign but extremely rare cases can have lymph node metastasis. Up to date, there have been only very few reports concerning SH with lymph node metastasis. In this paper we reported one pulmonary SH case with lymph node metastasis and additionally overviewed the clinical and pathological features of SH. A young-aged female was found incidentally to have a nodule in the right upper lung. This patient presented no cough, no hemoptysis and chest pain. Computed tomography (CT) scan indicated a large mass in the right upper lung and enlarged lymph nodes in the right hilum. The patient underwent lobectomy of the right upper lung. Histologically, the tumor demonstrated typical features of SH and was consisted of angiomatoid areas, sclerosis, papillary structures lined with cuboidal cells and sheets of round to polygonal cells. Polygonal cells in some solid areas presented abnormal enlarged nuclei and increased karyoplasmic ratio; tumor giant cells were noted; whereas mitosis was not observed. One peribronchial lymph node was noted for SH metastasis and the metastatic tissue were consisted of polygonal cells. Immunohistochemistry (IHC) revealed that both surface-lining cuboidal and polygonal cells expressed EMA and thyroid transcription factor 1 (TTF-1), but were negative for CD34, VIII factor, CD68 and Claratinin. The polygonal cells showed relatively higher expression of Ki-67 and p53 than the surface-lining cells. Postoperatively, the patient received no chemotherapy or radiotherapy and no recurrence 2 years after surgery was noted.

Sclerosing hemangioma of the lung mimicking pulmonary metastasis.

Sclerosing hemangioma (SH) of the lung is a rare, benign neoplasm, initially thought to be of vascular origin, but immunohistochemical results suggest an origin from primitive respiratory epithelium. We report a case of SH initially misdiagnosed as malignant due to the strong FDG-PET uptake.

Ten cases of resected solitary pulmonary metastases arising from gastric cancer.

BACKGROUND: Because carcinomatous lymphangitis and carcinomatous pleuritis are the usual forms of metastasis associated with gastric cancer, resection of solitary pulmonary metastases arising from gastric cancer is rarely performed. To clarify the characteristics of pulmonary metastases from gastric cancer, we investigated patients who underwent resection of metastatic solitary lung tumors arising from gastric cancer. METHODS: Between October 2003 and October 2012, 10 patients underwent pulmonary metastasectomy for metastatic gastric cancer at our institution. We retrospectively evaluated features of the primary gastric cancer and the clinicopathological features of the pulmonary metastases in these cases. RESULTS: 70% of the patients had stage II disease. Lymphatic invasion was observed in all cases of primary gastric cancer. The method of pulmonary resection was partial resection in 5 cases, segmentectomy in 1, and lobectomy in 4. On histopathological examination, immunohistochemical staining was negative for thyroid transcription factor-1 and napsin A in all cases. Patients who underwent resection of pulmonary metastases arising from gastric cancer had a good prognosis: the 4-year survival rate was 75%. CONCLUSIONS: Carefully chosen patients have a good opportunity to obtain benefits from resection of pulmonary metastases arising from gastric cancer.

Post cardiac transplantation T-cell lymphoproliferative disorder presenting as a solitary lung nodule.

Post-transplantation lymphoproliferative disorder (PTLD) is an infrequent, but serious complication of solid organ and bone marrow transplantations. The vast majority of the cases are of B-cell origin and usually associated with Epstein-Barr virus (EBV) infection. The non-B (T and NK cell) PTLDs account for up to 14% of the PTLD cases in Western countries. We report a case of a 66-year-old man who received an orthotopic heart transplant for cardiomyopathy 7 years prior to presentation. He was referred to our institution with a hypermetabolic solitary right lower lobe lung nodule with an SUV of 9.2 on PET scan. The combined histomorphological and immunohistochemical pattern was most consistent with monomorphic PTLD, peripheral T-cell lymphoma with angioimmunoblastic features. Molecular studies showed clonal T-cell gamma receptor gene rearrangement. Primary pulmonary involvement of T-cell PTLD is extremely rare. This is the third reported case of T-cell PTLD after cardiac transplantation, primarily involving the lung. Further, studies will be required to determine the appropriate treatment and prognosis of this rare entity.

Pulmonary sclerosing hemangioma presenting with dense spindle stroma cells: a potential diagnostic pitfall.

Pulmonary sclerosing hemangioma (PSH) is an uncommon pulmonary tumor. Histologically, PSH typically consists of two types of cells, surface cuboidal cells and polygonal cells, four architectural patterns including papillary, sclerotic, solid, and hemorrhagic. Herein, we present a case of PSH in a 59-year-old Chinese female. The tumor was predominantly composed of solid area presenting with diffuse spindle cells rather than polygonal cells. Focally, classical papillary and sclerotic area could be seen. Immunohistochemical staining showed that the spindle cells were positive for TTF-1, EMA, Actin(SM) and Vimentin, and negative for cytokeratin, cytokeratin7, cytokeratin5/6, surfactant apoprotein A, surfactant apoprotein B, CD34, CD99, S-100, HMB45, Desmin, Synaptophysin, CD56, ALK and Calretinin. The immunophenotype of the dense spindle cells in this case was similar to that of the polygonal cells, and thus the spindle cells may be the variants of polygonal cells. Based on morphologic features and the immunohistochemical profile, the tumor was diagnosed as a PSH. The significance of spindle cells change is unclear for us. To our knowledge, this is the first reported case of PSH showing dense spindle cells in solid area. This case represents a potential diagnostic pitfall, as it may be misdiagnosed as a mesenchymal tumor such as inflammatory myofibroblastic tumor, synovial sarcoma, solitary fibrous tumor, leiomyoma, or even mesothelioma, especially if the specimen is limited or from fine- needle aspiration. VIRTUAL SLIDES: The virtual slide(s) for this article can be found here: http://www.diagnosticpathology.diagnomx.eu/vs/1235401622806126.

Unusual clinical behaviour of thymoma with recurrent myasthenia gravis.

A 58-year old man with thymoma and myasthenia gravis (MG) had undergone thymectomy 8 years ago with histopathologically confirmed non-invasive WHO-type AB thymoma. After 5 years of complete remission, symptoms of MG resurfaced, and a recurrent anterior mediastinal mass was detected for which he received radiotherapy. He presented to us 3 years later with productive cough and exertional dyspnoea; the positron emission tomography-computed tomography scan revealed a metabolically active pulmonary nodule in the right lung as the only site of disease for which a right lower lobectomy was done. Microscopy established an intrapulmonary WHO-type B2 thymoma and the patient is currently asymptomatic on steroids, anticholinesterase and immunosuppressant therapy. We discuss the variable and unpredictable course of thymomas; the possibility of transformation into more aggressive types with each recurrence, association with recurrent MG post-thymectomy and presentation several years later with metastatic disease.

A case of primary angiosarcoma of the lung presenting as a hemorrhagic bronchial tumor.

Pulmonary angiosarcomas are usually secondary tumors, and only a few primary cases have been reported. Effective strategies for treating this tumor have not been established, and the prognosis of affected individuals is generally very poor. We report a case of primary angiosarcoma presenting as a hemorrhagic solitary nodule at the bifurcation of the left main bronchus, followed for two years before surgery. Bronchial arteriography revealed a tumor stain sign, and racemose hemangioma of the bronchial artery was excluded. The hemoptysis was not controlled by repeated bronchial artery embolization, and the patient underwent left pneumonectomy with routine mediastinal lymph node dissection. Histopathologically, the excised tissue revealed a highly-cellular growth of atypical spindle cells with a storiform pattern. These atypical cells showed relatively low mitotic activity; the MIB-1 index was 10%. The tumor was diagnosed as a primary angiosarcoma of the lung by the following immunohistological findings: positivity for factor VIII-related antigen and CD31. One year after resection, the patient remains well without signs of recurrence.

Pulmonary tumor with notochordal differentiation: report of 2 cases suggestive of benign notochordal cell tumor of extraosseous origin.

Intraosseous benign notochordal cell tumor (BNCT) is a lesion postulated to be of notochordal cell origin. BNCT has recently been recognized as a potential precursor of classic chordoma, a rare malignant neoplasm usually presenting in the sacrococcygeal region, skull base, or mobile spine. Extra-axial chordoma is extremely rare, and only 2 cases of pulmonary chordoma have been reported previously. We describe herein 2 cases of hitherto-unreported lung tumors that were diagnosed as BNCT. The patients were a middle-aged asymptomatic man and woman who were each incidentally found to have a 15-mm pulmonary nodule on computed tomography. They underwent surgical resection of the tumors under a diagnosis of probable benign tumor of uncertain nature. Histopathologically, both tumors showed solid sheets of peculiar adipocyte-like univacuolated cells, multivacuolated cells, and less vacuolated cells with small, round nuclei and mildly eosinophilic cytoplasm. Mitosis was absent. These features were typical of BNCT. Immunohistochemically, the tumor cells in both cases were positive for brachyury, a transcription factor essential for notochordal cell differentiation and for other markers of notochordal cells including cytokeratins, vimentin, and S-100 protein. Postoperatively, extensive radiographic examination of the whole body revealed no evidence of a primary tumor elsewhere, and both patients are alive and well, with no evidence of disease 1 year after surgery. These 2 cases raise the possibility of a new explanation for the histogenesis of extra-axial chordomas: BNCT may be a precursor lesion of not only conventional axial chordoma but also of extra-axial chordoma.

Epithelial-myoepithelial tumour of the lung: a case report referring to its molecular histogenesis.

Tracheobronchial submucous glands can be considered the pulmonary equivalent of minor salivary glands and therefore they can develop most of the tumours originated in these. Nevertheless, in spite of the wide distribution of this kind of glands along the tracheobronchial tree, pulmonary salivary gland-like neoplasms are not very frequent. Among them, the most frequent are mucoepidermoid and adenoid cystic carcinomas. On the contrary, pulmonary neoplasms showing a mixture of epithelial and myoepithelial elements are extraordinary infrequent, with only 11 cases collected from literature.We present the case of a 76 year-old woman with no interesting pathological history, to whom a pulmonary nodule is detected during a study of unknown origin neutropenia. An upper right lobectomy is performed.After macro and microscopic study, the diagnosis of pulmonary epithelial-myoepithelial tumour is made. It is a low malignant potential tumour with capacity to locally recur and less frequently to metastasize. Our case has the peculiarity of not being connected neither to visceral pleura nor to bronchial tree; we have not found this characteristic in any literature reviewed case.These tumours have been named in a lot of different ways, including adenomyoepithelioma, epithelial-myoepithelial tumour, epithelial-myoepithelial carcinoma or epithelial-myoepithelial tumour of uncertain malignant potential.The p27/kip-1 protein plays a fundamental role in the development of these neoplasms. As we have verified in our case, its aberrant cytoplasmic location, besides its proved oncogenic function, would favour the proliferation of stem cells, which would explain both dual phenotype with presence of myoepithelial cells without connection with the bronchial tree, and TTF-1 immunostaining in epithelial cells.

Ciliated muconodular papillary tumour of the lung: a newly defined low-grade malignant tumour.

We present two cases of ciliated muconodular papillary tumour (CMPT) in this report. CMPT is a newly defined low-grade malignant tumour with ciliated columnar epithelial cells, occurring in the peripheral lung. Both patients underwent pulmonary resection due to an enlarged solitary pulmonary nodule. Pathological findings in both cases confirmed a papillary tumour with a mixture of ciliated columnar and goblet cells. The tumours were rich in mucous and had spread along the alveolar walls, as observed in bronchioloalveolar carcinoma. Nuclear atypia was mild, and no mitotic activity was observed. Immunohistochemically, tumour cells stained positive for carcinoembryonic antigen, thyroid transcription factor-1 and cytokeratin 7 but not for cytokeratin 20. The immunohistochemical staining patterns were almost identical to those of pulmonary adenocarcinoma. We definitively diagnosed as CMPT. Both patients remained relapse-free.

[Clear-cell tumor of the lung: description of a case 1 mm in diameter ("micro-sugar tumor")]. / Tumore a cellule chiare del polmone: descrizione di un caso di 1 mm di diametro ("micro-sugar tumour").

Clear cell ("sugar") tumour of the lung is a rare neoplasm, generally presenting as a discrete nodule on the chest X-ray. We report a case of clear cell tumour of the lung in a 64-year-old woman. The tumour at presentation was 1 mm in diameter.

Malignant solitary fibrous tumor of the pleura causing recurrent hypoglycemia; immunohistochemical stain of insulin-like growth factor i receptor in three cases.

We present three cases of malignant solitary fibrous tumors of the pleura (SFTP) that produced recurrent hypoglycemia. Removal of the tumors produced normoglycemia. The tumors were well circumscribed and lobulated, and consisted of firm masses weighing 1,150 g to 1,450 g with the greatest diameter of 15 to 20 cm. The tumors were composed of spindle cells in fascicles or in a haphazard arrangement and were highly cellular and mitotically active (3-8 mitoses/10 high-power fields), showing histologically malignant features. Ultrastructurally, fibroblastic features of the tumor cells were present. Insulin-like growth factors (IGF) have been implicated in the presentation of hypoglycemia. The serum insulin and C-peptide levels were not elevated. Serum IGF-I levels were also low with values of 97.4, 157.1 and 51.9 ng/mL (ref. 125-317 ng/mL), respectively. However, tumor cells were strongly positive for IGF-I receptor on immunohistochemical analysis. It is tempting to speculate that IGF-I contributes to the hypoglycemia, even though the circulating levels were low.