First reported case of tracheal schwannoma presenting with syncope: diagnostic challenges and surgical management

Abstract

Introduction

Tracheal schwannoma is a rare benign neurogenic tumor originating from Schwann cells of the peripheral nerve sheath and accounts for less than 0.2% of all primary tracheal tumors. It commonly presents with nonspecific respiratory symptoms such as wheezing, dyspnea, or cough, often mimicking more common conditions like asthma. Syncope, a clinical manifestation not previously reported, is a rare presentation of tracheal schwannoma.

Case presentation

The authors report a case of a middle-aged man with unexplained syncope, accompanied by a history of chronic cough and shortness of breath. Contrast-enhanced computed tomography (CT) identified a tracheal mass as the underlying cause of his symptoms. Histopathological analysis confirmed the diagnosis of tracheal schwannoma. The patient underwent tracheal resection and reconstruction, resulting in complete tumor removal, with no recurrence observed during follow-up.

Discussion

Tracheal schwannomas are rare benign tumors, typically presenting with nonspecific respiratory symptoms. This case describes an unusual presentation of syncope, likely due to airway obstruction and vagal compression. The diagnosis was confirmed by CT and histopathology, with surgical resection achieving complete tumor removal and symptom resolution. This highlights the importance of considering rare airway tumors in patients with syncope and respiratory symptoms, underscoring the need for timely diagnosis and intervention.

Conclusion

To the best of our knowledge, this is the first reported case of tracheal schwannoma presenting with syncope. It highlights the importance of considering rare airway tumors in patients with unexplained syncope and chronic respiratory symptoms and reinforces the value of timely imaging and surgical intervention for optimal outcomes.

HIGHLIGHTS

• Airway tumors should be considered in patients with chronic respiratory symptoms unresponsive to standard asthma or COPD treatment.

• Persistent respiratory symptoms with normal chest X-rays should prompt advanced imaging such as CT scanning or bronchoscopy to evaluate for central airway lesions.

• Recurrent syncope in a patient with respiratory complaints may signal critical airway obstruction requiring urgent assessment.

• Endoscopic removal is suitable for small, pedunculated tracheal schwannomas, but open surgical resection is preferred for large, broad-based, or carinal tumors.

• Complete surgical excision offers an excellent prognosis, but postoperative surveillance remains essential to detect rare recurrences early.

Introduction

Tracheal schwannomas which originate from the Schwann cells of the peripheral nerve sheath are rare benign tumors that account for less than 0.2% of all primary tracheal tumors^[1]. They are typically located in the distal third of the trachea and often present with nonspecific respiratory symptoms such as chronic cough, progressive dyspnea, and stridor. Tracheal schwannomas are frequently misdiagnosed due to their slow growth and indistinct clinical manifestations that lead to the development of complications and delays in management^[2].

The rarity of these tumors is highlighted by the limited number of cases documented in medical literature. To date, less than 100 cases of tracheal schwannomas have been reported with the majority involving adults between 30 and 60 years^[3,4]. Patients with tracheal schwannoma initially end up getting misdiagnosed for more common conditions like asthma and chronic obstructive pulmonary disease (COPD). This leads to complications starting with progressive airway obstruction that eventually leads to respiratory failure and in extremely rare instances, syncope^[5,6].

Syncope possibly arising due to airway obstruction, vagal compression, or cough-increased intrathoracic pressure, leading to a reduced venous return and consequent cerebral hypoperfusion is an extremely rare presentation and has not been previously associated with tracheal schwannoma^[7,8]. The diagnosis of this rare condition is confirmed through imaging [computed tomography (CT) scan or magnetic resonance imaging], bronchoscopy, and positive histopathology findings of Antoni A/B patterns and Verocay bodies. Surgery is the treatment of choice once tracheal schwannoma is confirmed, with endoscopic resection preferred for small tumors and open surgery for large tumors. After complete resection, the recurrence rate is reportedly below 5%, highlighting a good prognosis^[9].

We present a rare case of tracheal schwannoma in a 41-year-old male with a long-standing history of respiratory symptoms who developed recurrent episodes of syncope. This case emphasizes the importance of considering rare respiratory tumors in patients presenting with recurrent episodes of fainting with chronic respiratory problems for timely diagnosis and management. This case report has been reported following the SCARE criteria for surgical case reports^[10].

Case presentation

A 41-year-old male with a 2-year history of productive cough and shortness of breath (SOB) presented with new-onset syncope. Over this period, he experienced multiple exacerbations of cough and SOB, for which chest X-rays were repeatedly unremarkable. Each episode was managed with 7–14-day courses of corticosteroids, antibiotics, bronchodilators, and mucolytics. Now, he presented with worsening respiratory symptoms, accompanied by two episodes of syncope occurring 27 days apart. Following the first episode, he was treated for respiratory symptoms at a local hospital. After the second episode, he was referred to our hospital for further evaluation. He had an 18-pack-year smoking history. He had no significant past medical or surgical history.

On examination, his vitals were as follows: pulse, 102/min; blood pressure, 128/80 mmHg; respirations, 26/min and oxygen saturation, 95% on room air. There were bilateral rhonchi on chest auscultation. A provisional diagnosis of acute exacerbation of chronic bronchitis was made, and the patient was initiated on intravenous antibiotics (amoxicillin-clavulanate and levofloxacin), along with nebulized bronchodilators and corticosteroids. Despite this treatment, there was no significant improvement in his symptoms. A contrast-enhanced CT of the neck and chest was done thereafter which revealed a mildly enhancing bilobed soft tissue density lesion in the distal trachea measuring 16 × 17 × 28 mm (AP × TR × CC dimensions) just proximal to the carina. The mass was adherent to the wall of the trachea between 7 and 8 o’clock position and was extending to the right main bronchus. It also showed an exophytic component which was abutting and partially compressing the azygous vein (Fig. 1).

Figure 1.

Image (A) coronal post-contrast CT, image (B) axial post-contrast CT, image (C) CT 3D reconstruction of bronchial tree, image (D) virtual bronchoscopy showing a bi-lobed, soft tissue density mildly enhancing ovoid lesion in distal trachea adherent to right tracheal wall just proximal to carina causing luminal narrowing of trachea and extending into proximal right main bronchus. However, no lung collapse was seen.

On table rigid bronchoscopy revealed that the growth was present just above the carina occluding the lumen in an exophytic manner and extending into the right mainstem bronchus. The rest of the airway was clear. After confirmation of the finding, a right posterolateral thoracotomy was done. Chest cavity was opened on the upper border of the fifth rib. The growth inside the trachea was identified by palpating the trachea. The trachea was then opened making a horizontal incision just above the tracheal ring. The growth was identified and it was made sure that the growth didn’t involve the right main bronchus, but was only occluding the lumen. Two tracheal rings at which the growth was attached to the trachea at the point of origin were identified. Tracheal resection was done at this site by removing these tracheal rings. Following resection, the trachea was reconstructed with ethicon vicryl 3-0. The excised tissue was sent for histopathology.

Post-operative course remained uneventful and the patient was discharged home on the fifth post-op day. Bronchoscopy done in the sixth month showed no recurrence.

Histopathology revealed a neoplastic lesion composed of hypo and hypercellular areas (Antoni A and Antoni B) with Verocay bodies formation. The cells were spindled having eosinophilic cytoplasm and elongated nuclei with inconspicuous nucleoli (Fig. 2). All these features were suggestive of tracheal schwannoma.

Figure 2.

Hypo and hyper cellular areas (Antoni A and Antoni B) with Verocay bodies formation. The cells were spindled having eosinophilic cytoplasm and elongated nuclei with inconspicuous nucleoli, suggesting of tracheal schwannoma.

Discussion

Tracheal schwannomas are exceedingly rare benign tumors arising from Schwann cells of the peripheral nerve sheath. Despite their non-malignant nature, their location within the airway poses a risk of significant clinical complications due to progressive airway obstruction. Patients commonly present with symptoms such as cough, dyspnea, wheezing, stridor, or recurrent respiratory infections. In rare instances, severe airway compromise may lead to syncope, as was observed in our patient^[11]. The mechanism of syncope in such cases is primarily due to transient but severe hypoxia resulting from critical tracheal narrowing, especially during exertion or coughing, when increased airflow demand cannot be met due to mechanical obstruction. This leads to reduced cerebral perfusion and subsequent transient loss of consciousness. Additionally, increased intrathoracic pressure from coughing may further reduce venous return and cardiac output, compounding the risk of syncope^[12]. This presentation highlights the diagnostic complexity associated with tracheal schwannomas, particularly when they mimic more common respiratory conditions. Table 1 presents the comprehensive review of the cases of tracheal mass associated with neurological symptoms.

Table 1.

Comprehensive review of the cases of tracheal mass associated with neurological symptoms

Authors/years	Age/sex	Presenting complaints	Associated neurological symptom	Imaging/bronchoscopy findings	Treatment	Histopathology	Outcome
Provided case	41 years/male	Cough, shortness of breath	Syncope	Tracheal mass just proximal to carina and extending to right main bronchus with exophytic component and partially compressing the azygous vein	Right posterolateral thoracotomy; tracheal resection and end-to-end anastomosis	Schwannoma	Symptoms improved; no recurrence at 6 months
Esch, et al/2021[14]	65 years/female	Cough, hoarseness, dysphagia	Cervical pain, paresthesia and weakness of right arm	Tracheal mass in front of C7/Th1, beginning 5 cm below the vocal folds, with intramucosal growth over 3 cm length and obturating the lumen by 50%	Tracheal segmental resection with end-to-end anastomosis	Microcystic/reticular schwannoma	Symptoms improved; no tumor recurrence
Bots, et al/2019[15]	34 years/male	Shortness of breath, non-productive cough	Syncope	Mass with almost complete resection of distal trachea	Resection of the tumor, distal trachea and left main bronchus	Adenoid cystic carcinoma	Macroscopic recurrence requiring radiotherapy and brachytherapy
Hassan, et al/2015[16]	34 years/female	Shortness of breath, fever	Seizure	Mass at the right lateral wall of the trachea causing significant narrowing of the tracheal lumen	Right posterior lateral thoracotomy and tracheostomy; radiation therapy	Adenoid cystic carcinoma	Symptoms improved; no recurrence at 6 months

Since tracheal schwannomas are rare and often present with non-specific respiratory symptoms, they are frequently misdiagnosed. In clinical practice, such presentations are commonly attributed to more prevalent conditions like asthma or COPD, often leading to delays in diagnosis of 10–15 months on average^[11,13].

Asthma is characterized by reversible airway obstruction and is typically episodic, often triggered by allergens or exertions. COPD in contrast, presents with persistent, progressive airflow limitations, usually in older adults with a smoking history. In contrast, the obstruction caused by tracheal schwannoma is fixed and progressive. Moreover, patients with tracheal schwannoma may undergo prolonged treatment with bronchodilators or steroids without clinical improvement as observed in our patient. The lack of response to standard therapy should prompt further evaluation with imaging such as CT of the neck and chest or bronchoscopy. Imaging studies like CT scans help to get detailed images of the trachea, assess the size and extent of the tumor, evaluate soft tissue characteristics, and differentiate schwannoma from other tumor types. Bronchoscopy allows for direct visualization of the tracheal lesion and facilitates biopsy to obtain for histopathological examination (HPE) which can confirm the diagnosis by identifying characteristic features of schwannoma showing spindle-shaped Schwann cells with Antoni A and B areas and S-100 protein positivity^[17]. In our case, our initial differentials included asthma, COPD, vocal cord dysfunction, and central airway tumors. The respiratory symptoms strongly prompted us to consider asthma and COPD; however, lack of improvement with appropriate treatment and absence of lung hyperinflation were our cue to further testing. A CT scan chest was thus considered which revealed a tracheal mass, and subsequent bronchoscopy confirmed the presence of an obstructive lesion.

Treatment of tracheal schwannoma primarily involves surgical resection, which is often curative due to the tumor’s benign nature. For small, well-defined, and non-invasive lesions confined to the mucosal or submucosal layers, endoscopic approaches such as laser resection, electrocautery, or argon plasma coagulation via flexible or rigid bronchoscopy can be effective. These techniques are minimally invasive, associated with shorter recovery times, and are particularly suitable for pedunculated tumors with minimal risk of bleeding or perforation^[18,19]. However, the suitability of endoscopic management is highly dependent on the size, depth, anatomical location, and extent of tracheal involvement. Larger or more invasive tumors, particularly those with broad-based attachment, deep mural infiltration, or proximity to critical airway bifurcations, are poor candidates for endoscopic removal due to the risk of incomplete resection, recurrence, or intraoperative airway compromise. In such scenarios, open surgical approaches, such as segmental tracheal resection with end-to-end anastomosis, become necessary to achieve complete and safe excision^[20]. In our case, the patient presented with a moderately sized lesion in the distal trachea, measuring 16 × 17 × 28 mm. Although not exceedingly large in absolute dimensions, the anatomical complexity of the tumor was clinically significant. It was located near the carina, extended into the right main bronchus, involved the posterior tracheal wall, and partially compressed the azygous vein. These features not only posed a challenge for endoscopic access and visibility but also increased the risk of incomplete removal or vascular injury during minimally invasive procedures. Furthermore, involvement of the carinal region raises concerns about airway instability post-debulking if not managed with proper surgical planning. Given these considerations, we proceeded with an open surgical resection to ensure complete tumor removal, preserve airway integrity, and minimize the risk of recurrence. The mass was excised and sent for HPE, which confirmed the diagnosis of schwannoma. As a benign tumor, tracheal schwannoma generally has an excellent prognosis following complete resection, with a low risk of recurrence^[21]. Nonetheless, regular postoperative surveillance is recommended, as incomplete excision may result in tumor regrowth^[22]. Ge, et al reported a recurrence in 2 weeks due to incomplete endoscopic resection of the tumor^[3]. Once recurrence occurs, open surgical tracheal resection becomes absolute.

Conclusion

This case represents the first documented instance of tracheal schwannoma presenting with recurrent syncope, expanding the clinical spectrum of this rare airway tumor. It highlights the diagnostic challenge posed by non-specific respiratory symptoms and underscores the importance of considering rare structural causes in patients with unexplained syncope. Early use of imaging and bronchoscopy is essential for accurate diagnosis, especially when initial treatment for presumed common conditions fails. Definitive surgical resection led to complete resolution and no recurrence, reinforcing its role as the optimal treatment approach. By reporting this unique presentation, our case contributes meaningful insight to the limited body of literature on tracheal schwannomas and calls for increased clinical vigilance to ensure timely recognition and management.

Ethical approval

Our institution does not require ethical approval for reporting individual cases or case series.

Patient consent

Written informed consent was obtained from the patient for publication and any accompanying images. A copy of the written consent is available for review by the Editor-in-Chief of this journal on request.

Sources of funding

The author(s) received no financial support for the research, authorship, and/or publication of this article.

Author contributions

M.W., R.T., and R.C. developed the study design. M.W., A.J., M.R., and N.P. did the literature review. All authors contributed to the first draft of the manuscript. A.A., A.A.R., and J.C. created, labeled, and added captions to the images. All authors approved the final manuscript.

Conflicts of interest disclosure

The author(s) declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article.

Research registration unique identifying number (UIN)

Not applicable.

Guarantor

Dr. Munna William and Dr. Rejina Chhetri.

Provenance and peer review

Not commissioned, externally peer-reviewed.

Data availability statement

Not available.

Assistance with study

None.