Primary pulmonary meningioma: report of a case and review of the literature

Pulmonary primary meningioma: A report of two cases and review of the literature

Introduction

Primary pulmonary meningioma (PPM) is rare, mostly asymptomatic, and difficult to recognize preoperatively. In this report, we describe two new cases of PPM and provide an updated review of the literature to enhance our understanding of PPM.

Case presentation

The first patient was a 53-year-old woman with an asymptomatic solitary pulmonary nodule in the right lower lobe on chest computed tomography (CT). Wedge resection of the right lung was performed and histological features of benign PPM were pathologically confirmed, which was further supported by immunohistochemistry. The second patient was a 63-year-old man who had a left pulmonary nodule during routine physical examination. CT revealed a solid nodule in the outer basal segment of the left lower lobe. The patient underwent a wedge resection of the left lower lobe and mediastinal lymph node dissection. Postoperative pathology confirmed the presence of two tumors: one adenocarcinoma and one PPM. Both cases were confirmed to be benign PPM (grade I) by pathological examination, with histological subtypes of fibrous and psammomatous.

Conclusions

Radiological imaging is crucial for the early detection of PPM, while pathological examination is necessary to confirm the diagnosis. Surgical treatment is recommended, and intraoperative frozen sections are essential for determining the extent of the operation.

Primary pulmonary meningioma: A case report and review of the literature

BACKGROUND

Primary pulmonary meningioma (PPM) is a rare disease that is usually benign. The most common presentation of PPM is isolated pulmonary nodules or masses, so the disease can mimic any other lung tumor on imaging, especially lung cancer or metastasis.

CASE SUMMARY

A 47-year-old asymptomatic woman presented with a well-defined, lobulated pulmonary mass with calcification in the left lower lobe. The mass measured 69 mm × 57 mm × 61 mm and was found during a chest computed tomography (CT) performed for physical examination. Contrast-enhanced CT and positron emission tomography (PET)/CT revealed mild enhancement of the mass, with accumulation of 18-fluoro-2-deoxy-D-glucose (¹⁸F-FDG). Transbronchial biopsy suggested a provisional diagnosis of low-grade neuroendocrine tumor. Subsequent enhanced head magnetic resonance imaging revealed no positive lesions. An open cuff resection of the left lower lobe and wedge resection of the lingual segment were performed. Histopathological and immunohistochemical examination revealed that the mass was a PPM.

CONCLUSION

PPM should be considered in the differential diagnosis of isolated pulmonary masses found incidentally on CT and should be diagnosed based on a combination of radiological and histological features. Surgical resection is currently the main treatment strategy. No recurrence of benign PPMs has been reported after complete resection.

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.

Extracranial meningiomas concurrently found in the lung and vertebral bone: a case report

Background

Primary pulmonary meningiomas are very rare, and primary intraosseous meningiomas outside the head and neck region have not yet been reported. We report an extremely unusual case of concurrent meningiomas arising in the pulmonary parenchyma and vertebral bone.

Case presentation

A 40-year-old Asian woman presented with a destructive lesion of the lumbar vertebral bone and a small nodule in the right lung. Five years later, both lesions slightly increased in size. To evaluate both the pulmonary and vertebral lesions, video-assisted thoracic surgery and curettage of the lytic lesion were performed. Both lesions showed similar histopathological findings corresponding to an intracranial meningioma of World Health Organization grade 1. The patient made good postoperative progress and remained free from disease at 41 months after the operation.

Conclusions

Our patient presented with almost synchronous pulmonary and lumbar vertebral intraosseous meningiomas. Regarding the relationship between the two lesions, there are two possibilities: Independent tumors occurred coincidentally or the primary pulmonary meningioma metastasized to the vertebral bone despite its bland morphology. It is important to keep in mind the exceptionally rare condition of extracranial meningioma.

Primary Pulmonary Meningioma: Report of a case and Review of the Literature

Primary pulmonary meningiomas are rare and their occurrence has been reported only sporadically. The diagnosis of such tumors should be accepted only after the presence of an intracranial or intraspinal meningioma has been excluded. The morphological and immunohistochemical features are similar to those of intracranial meningiomas. A case of primary pulmonary meningioma along with a review of the literature and discussion of other lesions in the differential diagnosis of this rare neoplasm are here presented.

Computed tomography findings of primary pulmonary meningioma: A case report

RATIONALE

Primary pulmonary meningiomas are extremely rare, and only a few cases have been reported in the medical literature. Imaging findings of primary pulmonary meningiomas have been reported even more rarely.

PATIENT CONCERNS

We present the case of a 54-year-old male patient with cough and sputum lasting for 20 years. This was a case of primary pulmonary meningioma with initial suspicion of a chest wall intercostal neurinoma.

DIAGNOSES

A lung lesion was detected on chest computed tomography (CT) imaging 4 years ago. This case appeared as a solitary well-defined round nodule close to the left chest wall, with heterogeneous enhancement on CT, which inaccurately led to the suspicion of a chest wall intercostal neurinoma.

INTERVENTIONS

A thoracoscopic wedge resection was performed.

OUTCOMES

The postoperative histological diagnosis was primary pulmonary meningioma. After 2 years of follow-up, the patient is still alive without evidence of metastasis or recurrence.

LESSONS

Increased awareness of the CT characteristics of this rare tumor may broaden the radiologist's knowledge base.

Intranodal meningothelial proliferation in a patient with Cowden syndrome: a case report

Ectopic meningothelial proliferations are rare and can occur in a multitude of extracranial/spinal anatomic locations. Perineurioma is another uncommon entity that shares similar histological characteristics to those found in meningothelial proliferations. These include bland spindle cells with thin, bipolar nuclei; eosinophilic cytoplasm; and indistinct cell borders, arranged in short fascicles with whorl formation. Given their uncommon occurrence and shared histological and immunohistochemical features, their distinction can present a diagnostic challenge. Immunohistochemical studies can provide guidance when attempting to distinguish between these 2 lesions. Here, we present an unusual case of a patient with Cowden syndrome who was discovered to have a meningothelial proliferation within an axillary lymph node. To the best of our knowledge, this is the first case in which a meningothelial proliferation has been identified in a lymph node. Furthermore, the occurrence in a patient with Cowden syndrome is intriguing and raises the possibility of a pathogenetic link.

Multiple primary pulmonary meningiomas: 20-year follow-up findings for a first reported case confirming a benign biological nature

INTRODUCTION

Primary pulmonary meningiomas (PPMs) are very rare neoplasms, and we reported the first multiple case of PPMs in 1998. Usually, PPMs are slow-growing tumors with a good prognosis. Herein, we reported a rare multiple case of PPMs with an extremely long clinical course.

PRESENTATION OF THE CASE

An 84-year-old Japanese woman with a history of multiple PPMs histologically confirmed as having a right-sided slowly growing lung nodule for 20 years. In 2010, we also reported the additional clinical course in the initial case 10 years after surgery implying a benign biological nature. Subsequent to that report, new lesions appeared in the bilateral lung fields with quite a slow growth rate. She was asymptomatic, and no tumor was observed in the cranial cavity during the course of her disease.

DISCUSSION AND CONCLUSION

This case illustrates rare multiple PPMs and highlights their biological behavior with very slow progression from a most likely benign tumor over a 20-year period.

Primary ectopic atypical meningioma in the renal hilum: a case report

BACKGROUND

Primary ectopic atypical meningioma involving the renal hilum is rare. This is, to our knowledge, only the second case report of a primary retroperitoneal meningioma and the first case of an atypical subtype in this location.

CASE PRESENTATION

A 53-year-old Han Chinese man presented with a 2-year history of left-side flank pain. An oval-shaped retroperitoneal mass was found in the left renal hilum on computed tomography, which was resected en bloc along with the kidney via laparotomy. According to the World Health Organization criteria, the tumor was histopathologically classified as a meningioma (Grade II, atypical). Five years later, the tumor recurred at the primary site with a similar histopathology. The patient received palliative resection, followed by radiotherapy (4500 cGy in 25 fractions). No relapse was found at 6-month follow-up.

CONCLUSION

We describe the clinical, radiographic and histopathological features of an unusual case of aggressive ectopic meningioma in the renal hilum. The patient presented with a massive retroperitoneal tumor without primary cerebral or secondary metastatic lesions; the preoperative diagnosis was naturally confined to the common retroperitoneal malignancies. This case is of interest to oncologists, because of both its rare location and aggressiveness; it not only enriched the spectrum of primary ectopic meningioma, but also reminded us of potential recurrence of an atypical meningioma. This case raises the issue of the etiology of such a rare tumor that needs further investigation, and more importantly demands long-term follow-up result.

Is primary pulmonary meningioma a giant form of a meningothelial-like nodule? A case report and review of the literature

Minute pulmonary meningothelial-like nodules (PMNs) are asymptomatic, small nodules that are occasionally detected in surgical or autopsy specimens. Recent improvements in tumor imaging and the increased use of computed tomography (CT) scans of the chest have led to the early detection of these pulmonary nodules in various clinical settings, often before surgery or health examinations. However, large PMNs have rarely been observed. In this study, we report a patient with a large PMN, which was almost identical to so-called ‘primary pulmonary meningioma’. A CT scan of his chest revealed a small, well-circumscribed nodule. Immunohistochemical analysis of the tumor revealed that the tumor cells were positive for CD56, epithelial membrane antigen, and progesterone receptor. Given the similarity of these results to the staining pattern of minute PMNs in previous reports, we suggest that the primary pulmonary meningiomas reported to date are, in fact, a giant form of PMN.

Multiple Pulmonary Metastases following Total Removal of a Bilateral Parasagittal Meningioma with Complete Occlusion of the Superior Sagittal Sinus: Report of a Case

Pulmonary metastases of benign meningiomas are extremely rare. The case of a 34-year-old man with bilateral parasagittal meningioma who developed pulmonary metastases is described. The meningioma was an enormous hypervascular tumor with invasion of the superior sagittal sinus. The tumor was resected completely and histologically diagnosed as transitional meningioma. The Ki-67 labeling index was 5%. Four months after operation, the patient subsequently developed bilateral multiple lung lesions later identified as metastases. The lung lesions were partially removed surgically and histologically diagnosed as meningothelial meningioma WHO grade I. The Ki-67 labeling index was 2%. The histological findings demonstrated that the tumor occupied the arterial lumen and the perivascular space, suggesting that pulmonary tumors might metastasize via the vascular route. The histopathological features and mechanisms of metastasizing meningiomas are reviewed and discussed.

Clinical characteristics and treatment of ectopic meningiomas

We have examined the clinical characteristics and treatment of ectopic meningiomas (EMs). Samples from 17 patients with EMs were analyzed, and their clinical characteristics, mechanism, and treatment were studied in combination with the literature. The main clinical manifestations of EMs included increased intracranial pressure, epilepsy, local mass, and local occupying effects, but diagnosis of EMs depended on the pathology. Surgical removal can achieve the double objectives of confirmed diagnosis and treatment of tumors. The clinical characteristics of EMs vary with the sites of tumors. Operation is the treatment of first choice. Prognosis is better than that of typical meningiomas.

Benign Tumors and Tumorlike Conditions of the Lung

Context.—Benign tumors and tumorlike conditions of the lung are encountered in the pathologic evaluation of asymptomatic and symptomatic lung nodules. Since many of these lesions are uncommon, they can be diagnostically challenging.

Objective.—To review the current classification of benign lung tumors, with emphasis on histopathology and useful ancillary studies.

Data Sources.—The current World Health Organization classification system for lung neoplasms and review of relevant publications.

Conclusions.—Despite improved imaging techniques, benign lung nodules are encountered in wedge biopsy and resection specimens. Histopathology, immunohistochemistry, and molecular techniques ensure accurate pathologic diagnosis and have shed light on the histogenesis of these unusual lesions.

Primary pulmonary meningioma: report of a case and review of the literature

Primary pulmonary meningioma (PPM) is a rare disease and usually presents as a solitary pulmonary nodule (SPN). These lesions are mostly benign, but malignant PPMs have been reported, and primary lung cancer or metastasis may be suspected on imaging. We report one case of benign PPM, with a review of 37 cases published in the literature. Diagnostic work-up included radiological chest study and in 3 cases positron emission tomography (PET) showing increased uptake, highly suspicious for malignancy. After exclusion of 13 cases lacking radiological studies of the central nervous system (CNS), 25 patients with radiological data and histological assessment confirming PPM were considered in the analysis. All patients underwent surgical resection except for 1 case with diagnosis at autopsy. Histological assessment revealed benign PPMs in 23 cases (including all 3 cases with positive PET) and malignant PPMs in 2 cases. No recurrence was observed in long-term follow-up of patients with benign PPMs, but the two malignant PPMs relapsed. PPM is an uncommon SPN, so that it can be misdiagnosed and its management unsuited. Indeed, 8 patients (32%) were overtreated with major thoracic surgical resection or with chemotherapy. When feasible, pulmonary wedge resection by video-assisted thoracic surgery (VATS) including intra-operative histological examination is the most suitable approach to determine the diagnosis and the volume of pulmonary resection.

Meningioma of the scapula

Meningiomas account for approximately 15% of all intracranial tumors and are the most common non-glial primary tumors of the central nervous system. Most meningiomas are benign neoplasms with characteristic imaging features. Primary extradural meningiomas account for only 1-2% of all meningiomas. They must be differentiated from intradural meningiomas with secondary extradural extension and/or metastases. The vast majority of extradural meningiomas are found in the skull or in the head and neck region. We report on an extremely rare case of primary extradural meningioma that was located in the scapula. The lesion was resected. Radiographic findings and pathologic features are discussed. To the best of our knowledge, this form of presentation of an extradural meningioma has not been previously described.

A case of neck ectopic meningioma

Primary extra cranial and extra spinal meningioma is rare and is usually limited to the head and neck region or to the paravertebral soft tissues. Histologic diagnosis (in particular for fresh specimens) is often difficult. A 16-year-old girl with a cervical mass is presented. It was a relatively large mass with an approximate diameter of 5 cm. It was diagnosed in fine needle aspiration as a pleomorphic adenoma. Intra-operative diagnosis was paraganglioma and frozen section suggested an infiltrative tumor. Histologically, the lesion showed uniform spindle cell proliferation separated by hyalinized collagen bundles. The cells were often arranged in sweeping fascicles and concentrically wrapped in tight whorls. Immunohistochemically, tumor cells were positive for epithelial membrane antigen and vimentin, while showing no reaction for cytokeratin, chromogranin, neuron-specific enolase and thyroglobulin. A diagnosis of ectopic meningioma was established based on microscopic appearance and immunohistochemical profile of the tumor. Despite its rarity, ectopic meningioma should be considered in differential diagnosis of any mass lesion in head and neck regions, containing spindle cells.

“Benign” metastatic meningioma: clinico-pathological analysis of one case metastasising to the lung and overview on the concepts of either primitive or metastatic meningiomas of the lung

Lung "metastases" of benign meningiomas are rarely described events of biological and clinical interest. We, here, report of a 70-year-old healthy woman found by CT scan to have multiple lesions, the two largest in the right lung on routine examination. Anamnesis revealed that the patient underwent a surgical resection of cerebral meningioma 12 years before. The larger lung lesion was a 3-cm node located in the right lung and was removed by wedge resection. Macroscopically, it showed well-defined borders, whitish colour and firm consistency; histologically, it was uniformly composed by spindle meningothelial cells arranged in fascicules including psammoma bodies. The morphological and immunohistochemical features of this lesion, together with the similarity with the original cerebral tumour and its indolent evolution, led to a final diagnosis of "benign" meningioma metastatic to the lung. Lung metastatic meningiomas may be a diagnostic challenge because of their unusual site of presentation and the possible confusion with primitive lung meningiomas or primary mesenchymal lung lesions. They represent a typical example of "benign" tumours that may implant to the lung similar to other tumours, definitely considered benign but reported to rarely present unusual secondary localization.

Primary pulmonary meningioma first suspected of being a lung metastasis

Primary extracranial and extraspinal meningiomas are rare tumors. We describe a primary pulmonary meningioma first suspected of being a metastasis because it presented as a solitary subpleural pulmonary nodule in a patient with breast cancer. The absence of radiographic change after 6 months of chemotherapy led to resection of the breast and lung lesions. A complete central nervous system evaluation eliminated other locations of meningioma, allowing the diagnosis of primary pulmonary meningioma.

Meningioma of the Mediastinum Causing Spontaneous Hemothorax

Ectopic meningiomas are extremely rare. Mediastinal tumors may rarely cause spontaneous hemothorax. We report a case of angioblastic meningioma of the posterior mediastinum causing spontaneous hemothorax.

Primary chordoid meningioma of lung

Primary meningiomas of the lung are rare. Most pulmonary meningiomas are typical syncytial or transitional meningiomas with smaller numbers of fibrous-type tumors. Herein, we report an unusual pulmonary tumor with the microscopic, immunohistochemical, and ultrastructural characteristics of a chordoid meningioma. The tumor was composed of cords and fascicles of small- to medium-sized spindle and epithelioid cells with eosinophilic cytoplasm and round nuclei with finely dispersed chromatin. The tumor cells were surrounded by an abundant mucoid, vacuolated stroma. The periphery of the tumor was enveloped by a significant lymphoplasmacytic infiltrate. The neoplastic cells were positive for vimentin and epithelial membrane antigen only. The unusual morphology of the tumor caused significant diagnostic difficulties. The differential diagnosis included inflammatory myofibroblastic tumor, spindle cell myoepithelioma, and extraskeletal myxoid chondrosarcoma. To the best of our knowledge, this is possibly the first description of an extracranial or intrapulmonary chordoid meningioma.

Ectopic neural and neuroendocrine neoplasms

Although neural and neuroendocrine tissues are distributed virtually ubiquitously throughout the body, the occurrence of selected neoplasms related to those lineages is extremely uncommon in some topographic sites. This review considers the clinicopathologic characteristics of heterotopic pituitary adenomas; neuroendocrine carcinomas in non-organ-based locations; ectopic (extraneuraxial) meningiomas and gliomas; visceral neuroblastic neoplasms and primitive neuroectodermal tumors; and paragangliomas arising outside the sympathoadrenal neural network. Practical approaches to differential diagnosis are emphasized.

Rare solitary benign tumors of the lung

Benign solitary neoplasms of the lung are relatively uncommon but nonetheless must be considered in the differential diagnosis of any solitary pulmonary lesion. Ironically, the advent of improved tomographic imaging and its increasingly broad clinical application have led to a greater recognition of benign solitary pulmonary lesions, presenting the surgeon with a complex management dilemma. Most benign lesions are relatively bland radiographically, making their differentiation from carcinoma difficult. Often, diagnostic certainty can only be achieved with complete resection. Fortunately, advances in minimally invasive thoracic surgery make this prospect less daunting for the patient and surgeon. This article reviews a subset of solitary lesions categorized as rare benign neoplasms from histologic, radiographic, and clinical points of view.

Meningioma metastatic to the lung

Meningiomas constitute 15% to 18% of all primary intracranial and intraspinal tumors. Distant extracranial metastases are reported to occur in fewer than 1 in 1000 cases. Of 1992 primary intracranial meningiomas seen at Mayo Clinic Rochester from 1972 through 1994, we identified 3 (0.15%) with documented extracranial metastasis. A review of the literature suggests that previous craniotomy, venous sinus invasion, local recurrences, histological malignancy, and papillary morphology may be risk factors for systemic spread, as demonstrated in our cases. Although rare, metastatic meningioma should be considered in the differential diagnosis of abnormal findings on chest radiography in patients with known or suspected intracranial meningioma.

Primary pulmonary malignant meningioma

Fewer than 20 cases of primary pulmonary meningioma have been reported. Most of these cases have been histologically and clinically benign. We report an unusual case of primary pulmonary malignant meningioma with atypical histologic features and malignant behavior. A computed tomography scan of the head did not show evidence of tumor. The right upper lobe mass was resected and showed features of an atypical meningioma with loss of architectural pattern, mild nuclear pleomorphism, increased mitotic counts (up to 15 mitotic figures per 10 high power fields), and focally prominent nucleoli. Focally, cells with rhabdoid features were identified. The tumor's immunohistochemical and ultrastructural profiles were consistent with a meningioma. The tumor stained negative for estrogen and focally positive for progesterone receptors and had a MIB-1 labeling index (marker of cell proliferation) of 9.2%. Approximately 5 months after the initial resection, the patient experienced a tumor recurrence with multiple lymph node metastases, spread to the middle and lower lobes of the right lung, and metastasis to the diaphragm. Rarely, primary pulmonary meningiomas may present as high-grade malignant lesions.