A Young Man With Primary Pulmonary Myxoma

ABSTRACT

Primary pulmonary myxoma is a rare tumor and is usually diagnosed incidentally in clinically asymptomatic patients as a well‐defined lung mass without metastasizing. It should also be considered that diagnostic methods such as bronchoscopy or transthoracic aspiration may be nondiagnostic. Thus, tumor resection is essential for diagnosis and treatment.

1. Introduction

Myxoma is a morphologically benign tumor that frequently occurs in the left atrium [1]. Primary pulmonary myxoma is a rare tumor and is usually found as an incidental well‐demarcated pulmonary mass without symptoms. Myxomas are usually found as a single mass, growing from the primary lesion and do not produce distant metastases. The pathological characteristic of these tumors is the presence of elongated and stellate cells in a myxoid stroma. Since it is difficult to diagnose these tumors based on small biopsy samples or cytology, tumor resection is necessary for diagnosis and treatment [2]. Given the few reports on primary pulmonary myxoma, we present a case of this tumor in a young adult man.

2. Case History/Examination

A 29‐year‐old male patient without any underlying disease presented to the emergency department of our hospital with a productive cough and pleuritic chest pain in the left hemithorax with radiation to the left shoulder since 2 months ago. He also complained of occasional hemoptysis and orthopnea for 4 months. The patient had a nonsignificant weight loss and mentioned occasional cigarette smoking.

On presentation, vital signs and laboratory investigations were unremarkable.

CT scan demonstrated a large oval‐shaped homogeneous mass sized 50*80 mm with well‐demarcated margin in the left lower lobe extending from the left hilum to the periphery as a pleural base density and increased pleural thickness with surrounding reticular opacity (Figure 1).

FIGURE 1.

CT scan showed large homogeneous oval‐shaped, well‐demarcated mass in left lower lobe.

3. Differential Diagnosis, Investigation, and Treatment

The differential diagnosis of a lung mass in a 29‐year‐old man includes a broad range of infectious, neoplastic, inflammatory, and congenital conditions. Therefore, different diagnostic methods should be used to diagnose the patient.

Initially, flexible fiber‐optic bronchoscopy was performed for the patient, which revealed a LLL bronchus fish mouth stenosis and LB6 complete obstruction due to external compression and mucosal erythema in LC2. BAL was taken from LLL, and EBB was performed in LC2 (Figure 2). BAL pathological examination reported mostly degenerated cells and few alveolar macrophages in mucoid background. It was negative for malignancy.

FIGURE 2.

Bronchoscopic view with stenosis at left lower lobe bronchus.

Diagnostic transthoracic aspiration was performed under ultrasound guidance. About 10 cc of very thick and mucinous fluid was drawn and sent for culture and Gram stain smear and pathologic examination.

Fluid pathological examination revealed several mesothelial cells in a hemorrhagic background with a negative microbiologic result.

Ultimately, the patient became a candidate for surgical resection. So surgical resection of the left pulmonary mass was scheduled and performed by the thoracic surgeon. There was a large lung mass with adhesion to the surrounding tissues in the posterior segment of the left lower lobe (Figure 3). The cut surface of the mass showed large amounts of fragmented gelatinous contents (Figure 4). The frozen section specimen was reported to be consistent with hamartoma.

FIGURE 3.

Surgical view of the tumor.

FIGURE 4.

Fragmented gelatinous contents within the tumor.

Gross pathological examination of resected tumor revealed a cream‐brownish mucoid gelatinous circumscribed tissue and a piece of cream‐whitish gelatinous mass. Under high microscopic magnification, a benign hypocellular neoplasm composed of delicate spindle‐shaped and stellate cells in abundant myxoid stroma with no mitotic figures lined by a collagenized capsule was seen. The findings were compatible with myxoma. Lymph nodes had nonspecific pathologic changes (Figure 5).

FIGURE 5.

Pathologic examination of resected tumor revealed hypocellular neoplasm composed of delicate spindle shape and stellate cells in abundant myxoid stroma with no mitotic figures.

Immunohistochemical analysis revealed positive staining for vimentin (+), a Ki67 index of less than 1% positive, and negativity for AE1/AE3, S100, Myogenin, Calretinin, GFAP, TTF1, and P63, which was compatible with pulmonary myxoma.

4. Conclusion and Results

As mentioned, the final diagnosis was primary pulmonary myxoma. The patient did not have any complications after surgery and was finally discharged with stable respiratory symptoms.

5. Discussion

We present a young adult male patient with pulmonary myxoma with a left lower lobe mass, in whom initial evaluations at bronchoscopy and transthoracic aspiration were not diagnostic. Interestingly, the patient's frozen sample was reported as hamartoma. Finally, a definitive diagnosis of pulmonary myxoma was made based on pathological and immunohistochemical analysis of the resected mass.

As noted in the patient, initial evaluations with transthoracic aspiration were nondiagnostic due to the low cellularity of the tumor.

Although the median age of patients with myxoma is reported to be 69 years [2], our patient was a young adult man.

Barkley and Cardozo reported the earliest case of pleuro‐pulmonary myxoma in 1957 [3]. Myxomas are benign mesenchymal tumors that can be found in multiple locations. The most common type of myxoma, which is most common in adults, is primary cardiac myxoma, accounting for 30%–50% of all cases of cardiac tumors [4]. These tumors originate from the primitive mesenchymal cells with potential endothelial differentiation. Transthoracic and transesophageal echocardiography are the primary diagnostic methods in these tumors to establish the diagnosis. Contrast echocardiography, computed tomography (CT), and cardiac MRI imaging are other modalities used to diagnose cardiac myxomas [5, 6].

In the differential diagnosis of cardiac tumors, primary malignant tumors should also be considered, including angiosarcoma and rhabdomyosarcoma, which are the most common malignant primary cardiac tumors. Other primary cardiac malignant tumors include leiomyosarcoma, undifferentiated pleomorphic sarcoma, osteosarcoma, synovial sarcoma, and fibrosarcomas. In contrast to the rarity of primary malignant cardiac tumors, cardiac metastases are more common and often arise from lung, pleural mesothelioma, skin melanoma, breast, esophageal, and hematological malignancies [7, 8]. It should be noted that all cardiac tumors are classified as middle mediastinal tumors [9].

As previously mentioned, primary pulmonary myxoma is rare and usually diagnosed as an incidental well‐defined lung mass in clinically asymptomatic patients [2]. Myxomas usually do not metastasize, but occasionally metastases to the brain, bone, and soft tissues are seen. On the other hand, local recurrence may be diagnosed as emboli or sarcomatous origin. Therefore, long‐term follow‐up is recommended for these patients [4]. In addition to pleuropulmonary myxomas, there are case reports describing myxomas arising in the pulmonary artery and mimicking pulmonary embolism and subacute cor pulmonale [10, 11]. There are also some reports of trachea and endobronchial myxoma with symptoms resembling asthma and repeated pneumonia [4]. Differential diagnoses for pulmonary myxoma include: myxoid liposarcoma, myxoid chondrosarcoma, myxoid malignant fibrous histiocytoma, pulmonary hamartoma, angiomyol,ipoma and pulmonary lipoma [3].

Author Contributions

Masoud Aliyali: data curation, investigation, writing – original draft, writing – review and editing. Parnaz Rajabi: data curation, investigation, writing – original draft, writing – review and editing. Gholamali Godazandeh: supervision. Siavash Abedi: supervision. Anahita Nosrati: supervision.

Ethics Statement

The authors have nothing to report.

Consent

Written informed consent was obtained from thepatient.

Conflicts of Interest

The authors declare no conflicts of interest.

Aliyali M., Rajabi P., Godazandeh G., Abedi S., and Nosrati A., “A Young Man With Primary Pulmonary Myxoma,” Clinical Case Reports 13, no. 9 (2025): e70815, 10.1002/ccr3.70815.

Data Availability Statement

Data sharing not applicable to this article as no datasets were generated or analyzed during this study.