Primary pulmonary meningioma presenting as multiple lung nodules: A case report

Incidental Metaplastic Primary Pulmonary Meningioma

Primary pulmonary meningioma is a rare benign tumor usually presenting as a solitary pulmonary nodule or mass. It can be easily misinterpreted as a primary lung tumor or metastases on imaging studies. We present a 54-year-old woman with an incidentally discovered solitary lung nodule, which was diagnosed as metaplastic primary pulmonary meningioma following resection. Metaplastic meningioma is a rare WHO grade 1 meningioma subtype with focal or global mesenchymal differentiation. To the authors' knowledge, primary pulmonary meningioma with mesenchymal differentiation has not been described previously in the English literature.

Primary Pulmonary Meningioma With Associated Multiple Micronodules: A Case Report With Comprehensive Diagnostic Overview

BACKGROUND

Primary pulmonary meningioma (PPM) is an exceedingly rare neoplasm originating in the meninges within the lung. Despite sharing similarities with its central nervous system (CNS) counterparts, PPM presents unique diagnostic challenges and therapeutic considerations owing to its infrequent occurrence.

CASE

This case report describes a 73-year-old male who underwent chest computed tomography (CT), which revealed a mass in the posterior basal segment of the right lower lobe, suggestive of a low-grade malignant tumor approximately 30-40 mm in size. Single-port video-assisted thoracoscopic surgery (VATS) was performed to resect the mass via localized lesion excision (lung wedge resection). Intraoperative frozen section pathology indicated a low-grade malignant epithelial tumor, leading to a decision for maximal lung function preservation, considering the patient's advanced age. The surgical team opted for a localized excision to ensure negative margins. Histopathological analysis confirmed the diagnosis of epithelioid PPM, a rare subtype even among PPM cases (World Health Organization [WHO] Grade I). The patient was discharged 9 days after surgery without complications and resumed normal daily activities 1 month postoperatively. The rarity of PPM precludes a standardized treatment protocol, with surgical resection as the primary approach. However, the efficacy of adjunctive therapies remains uncertain due to limited evidence.

CONCLUSION

This case report contributes to a better understanding of PPM and emphasizes the importance of a comprehensive diagnostic evaluation and individualized treatment planning for this rare entity.

Primary pulmonary meningioma and minute pulmonary meningothelial-like nodules: Rare pulmonary nodular lesions requiring more awareness in clinical practice

In this editorial, we comment on an article by Ruan et al published in a recent issue of the World Journal of Clinical Case. Pulmonary meningothelial proliferative lesions, including primary pulmonary meningiomas, minute pulmonary meningothelial-like nodules, and metastatic pulmonary meningiomas are rare pulmonary lesions. These lesions are difficult to differentiate from lung cancers based on clinical and imaging manifestations. Herein, we briefly introduce the clinical, imaging, and pathological characteristics of these lesions and discuss their pathogenesis to strengthen the current understanding of pulmonary meningothelial proliferative lesions in clinical diagnosis and therapy.

A Primary Pulmonary Meningioma That Grew Over 10 Years: A Surgical Case Report

Primary pulmonary meningiomas (PPMs) are rare meningothelial proliferation that lacks characteristic imaging findings, making their distinction from other peripheral lung tumors challenging. Therefore, surgical resection is often performed for the diagnosis and treatment of PPM. Herein, we describe a surgical case of PPM that grew over 10 years. A 63-year-old woman was referred to our department due to right middle lobe lung tumor enlargement. No significant symptoms were observed. Chest computed tomography revealed a tumor in the middle lobe of the right lung. F-18 fluorodeoxyglucose positron emission tomography showed accumulation in the nodule; thus, lung cancer could not be ruled out. Therefore, the preoperative differential diagnosis was cStageIB lung cancer. A right middle lobectomy was performed, and a histopathology examination revealed meningioma. There were no primary lesions in the head and whole spine magnetic resonance imaging, thus, a final diagnosis of PPM was made. Cautious observation is required postoperatively due to the possibility of recurrence.

PET/CT imaging of giant primary pulmonary meningioma: a case report and literature review

BACKGROUND

An ectopic meningioma, such as a primary pulmonary meningioma (PPM), is a rare type of tumor that primarily originates outside of the central nervous system. The most common presentation of PPM is isolated pulmonary nodules or masses, and most of them are benign. Only sporadic cases have been reported. This case reported a giant primary pulmonary meningioma and systematically reviewed previously reported cases in the literature.

CASE PRESENTATION

A 55-year-old female suffered from asthma after activity, chest tightness, and a persistent dry cough for 2 months. Chest computed tomography (CT) showed a huge mass with calcification in the left lower lobe. And positron emission tomography (PET)/CT revealed mild FDG accumulation of the mass. The mass was finally surgically removed and PPM was confirmed according to histopathologic examinations.

CONCLUSION

PPM is a rare disease with heterogeneity not only in CT features but also in glucose metabolism. FDG uptake levels do not identify benign from malignant, benign PPM may have high FDG uptake and malignant may have low.

Primary pulmonary meningioma with associated multiple micronodules: a case report and literature review

Primary pulmonary meningioma (PPM) is a rare and benign slow growing tumor with good prognosis. It often presents as an asymptomatic, well-circumscribed, solitary pulmonary nodule. Wedge resection is the management of choice for both diagnosis and treatment. Here, we report one case of PPM with increased fluorodeoxyglucose (FDG) uptake and associated micronodules, which was clinically suspicious for malignancy. The patient was a 60-year-old female who presented with persistent shortness of breath for 1 year. Chest computed tomography showed a 1.5-cm well-circumscribed homogenous nodule in the left upper lobe with increased FDG uptake and multiple smaller well-circumscribed micronodules scattered in both lungs. Left upper lobe wedge resection confirmed the diagnosis of PPM. PPM can deceptively mimic malignancy, so recognizing this rare entity and including it in the differential diagnoses of pulmonary nodules, especially with avid uptake of FDG, is crucial to avoid misdiagnosis and overtreatment.

Multiple primary pulmonary meningioma: A case report and literature review

Lung cancer has become a leading cause of cancer‐related deaths. With the conventional use of low‐dose spiral computed tomography (CT) in physical examinations, an increasing number of small pulmonary nodules are screened. However, primary pulmonary meningiomas (PPMs) are rarely reported. Here, we report the case of a 64‐year‐old woman who had a CT scan during physical examination, which revealed three ground‐glass‐like opacity pulmonary nodules in both lungs. The patient underwent video‐assisted thoracoscopic wedge resection of the right upper and lower lobes. Paraffin sections revealed pulmonary meningothelial‐like and collagenous nodules in the right upper and lower lobes which stained as follows: EMA+, VIM+, SMA‐, S‐100‐, CD34‐, STAT6‐, Ki‐67+ (2%), and CgA‐. Primary pulmonary meningiomas (PPMs) were finally diagnosed. PPM is a kind of rare and benign tumor. Surgery can provide a precise pathological examination, and patients can achieve an excellent prognosis after surgical resection.

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.