Successful complete tumor resection for pulmonary mucoepidermoid carcinoma by thoracoscopic right upper lobectomy with intraoperative bronchoscopy: A pediatric case report

Abstract

Introduction and importance

Mucoepidermoid carcinoma presents as an exophytic endobronchial mass that induces obstructive symptoms often followed by distal collapse atelectasis of the lung parenchyma.

Case presentation

A six-year-old girl had recurrent bacterial pneumonia and atelectasis of the right upper lobe. Computed tomography revealed a 30-mm mass in the anterior segment of the right upper lobe with an obstructed trachea and peripheral atelectasis. A minor salivary gland tumor was suspected, so thoracoscopic right upper lobectomy (RUL) was performed. Intraoperative bronchoscopy showed no protrusion of the tumor into the tracheal lumen. We confirmed that there was no injury to the middle lobe branch and no residual tumor via bronchoscopy before transection of the trachel bronchus of the right upper lobe. The histological type was low-grade mucoepidermoid carcinoma. The postoperative course was uneventful, and no recurrence was evident after one year.

Clinical discussion

Primary pulmonary cancers in children are extremely rare. Mucoepidermoid carcinoma is the most common disease in pediatric primary lung tumors but remains relatively rare. Mucoepidermoid carcinoma of the tracheobronchial tree sometimes requires sleeve resection. Intraoperative bronchoscopy helped determine the exact position of the tumor. The value of intraoperative bronchoscopy for sparing the lung parenchyma and preserving as much of the respiratory function as possible. Intraoperative bronchoscopy should be actively performed in cases of pediatric lobectomy, especially those involving tracheobronchial tumors.

Conclusion

Intraoperative bronchoscopy allowed for complete RUL without residual tumor or injury of the middle lobe bronchus.

Highlights

• •MEC is the most common disease in pediatric primary lung tumors but remains relatively rare.
• •There have been no previous reports on thoracoscopic lobectomy for pediatric MEC cases.
• •We performed complete tumor resection for pulmonary MEC by thoracoscopic right upper lobectomy with intraoperative bronchoscopy.

1. Introduction

While thoracoscopic surgery for children requires a high level of skill for pediatric surgeons, it has been well established as a minimally invasive and cosmetically pleasing procedure [1]^, [2]. Thoracoscopic surgery provides many benefits in both the short-term postoperative course and long-term outcomes of pediatric patients [3]^, [4].

Mucoepidermoid carcinoma (MEC) originates from the glands lining the tracheobronchial tree, and tumors can be classified as low- or high-grade lesions based on histopathologic results. MEC presents clinically as an exudative endobronchial mass, often resulting in obstructive symptoms with distal collapse atelectasis of the lung parenchyma.

In this study, we used intraoperative bronchoscopy to confirm that there was no injury to the middle lobe branch of bronchus and no residual tumor before transection of the right upper lobe branch. We herein report our intraoperative bronchoscopy technique in thoracoscopic right upper lobectomy for pulmonary mucoepidermoid carcinoma. This case report is compliant with the SCARE Guidelines [5].

2. Presentation of case

A six-year-old girl came to our institution with recurrent bacterial pneumonia and atelectasis of the right upper lobe. Chest X-ray showed that atelectasis remained after improvement of bacterial pneumonia (Fig. 1a). Computed tomography revealed a 30-mm mass in the anterior segment (S3) of the right upper lobe with an obstructed trachea and peripheral atelectasis (Fig. 1b). A minor salivary gland tumor was suspected. Thoracoscopic right upper lobectomy (RUL) was planned.

Fig. 1.

a: Chest X-ray. Chest X-ray showed that atelectasis remained after the improvement of bacterial pneumonia.

b: Computed tomography. Computed tomography revealed a 30-mm mass in the anterior segment (S3) of the right upper lobe with an obstructed trachea and peripheral atelectasis.

Under general anesthesia, the patient was placed in the left three-quarter prone position on the operative bed. The patient's right arm was fixed with a bed cradle at the head side to sufficiently ensure the axillary surgical field. We used four access ports. A thoracoscope was inserted through a 5-mm access port in the fifth intercostal space on the posterior axillary line. The operator's forceps were inserted through a 5-mm port in the third intercostal space on the mid-axillary line and a 5-mm port in the sixth intercostal space on the mid-axillary line. The assistant's forceps were inserted through a 12-mm port in the eighth intercostal space on the posterior axillary line (Fig. 2).

Fig. 2.

Port layout.

The tumor was located in the lung parenchyma of the upper lobe close to the hilar region. There was severe adhesion between the middle lobe, lower lobe, thoracic cavity and upper lobe. We dissected the interlobar fissure with a vessel sealing system (ENSEAL® X1 Curved Jaw; Ethicon Endo-Surgery, Cincinnati, OH, USA). The vascular anatomy of the right pulmonary arteries and veins was carefully confirmed using near-infrared fluorescence-guided techniques with indocyanine green (SV1). Polymer clips (Vesolock®, Polymer Ligation System; Symmetry Surgical Inc., Antioch, TN, USA) were fixed to the proximal end of the pulmonary arteries and veins, which were then transected with a vessel sealing system.

We then moved on to dissecting the right upper bronchus. The bronchus was lifted with the operator's right-hand forceps and clamped using a stapler (Powered ECHELON FLEX®7; ETHICON). We next confirmed that there was no injury to the bronchus of the middle lobe and no residual tumor in the proximal trachea via bronchoscopy before transsecting the right upper lobe bronchus (Fig. 3). After transection of the right upper bronchus, the resected specimen was placed into an endoscopic pouch (ENDOPOUCH RETRIEVER®; ETHICON). The 12-mm port was removed, and the incision at the port was enlarged to 4 cm. We extracted the specimen through the enlarged site. A 19-Fr chest tube (J-VAC® suction reservoir/blake® silicon drain; ETHICON) was inserted. All incisions were closed in layers.

Fig. 3.

Intraoperative findings.

We confirmed that there was no injury to the middle lobe bronchus and no residual tumor in the proximal trachea via bronchoscopy before transecting the right upper lobe bronchus.

The postoperative course was uneventful. We removed the chest drain tube on postoperative day 3, and she was discharged from the hospital on postoperative day 7. The patient was diagnosed with MEC of a low grade by pathologic findings. No recurrence was reported after one year.

3. Discussion

Primary pulmonary cancers in children are extremely rare [6]. The International Agency for Research on Cancer announced that approximately 439 new primary pulmonary cancer cases had been diagnosed in pediatric patients worldwide, accounting for fewer than 0.3 % of all cancers diagnosed in patients between 0 and 14 years old and <0.02 % of all lung cancers [7]. MEC is the most common disease in pediatric primary lung tumors but remains relatively rare. Mucoepidermoid carcinoma (MEC) originates from the glands lining the tracheobronchial tree, and tumors can be classified as low- or high-grade lesions based on histopathologic results.

MEC often affects the salivary glands, representing the second-most common salivary gland tumor. MEC of the lung is an extremely rare neoplasm that accounts for <1 % of all lung carcinomas. No associations between smoking or other risk factors have been reported, and MEC does not appear to have any sex predilection, with the age of presentation ranging from 3 to 78 years old [8]. MECs are typically endobronchial, often arising in the segmental or lobar bronchi. MEC presents clinically as an exudative endobronchial mass, often resulting in obstructive symptoms with distal collapse atelectasis of the lung parenchyma. The clinical symptoms and signs of pulmonary MEC include cough, hemoptysis, bronchitis, wheezing, a fever, and chest pain and commonly resemble the symptoms of pneumonia [9]. Making a diagnosis tends to take a long time because the disease mimics other syndromes, such as asthma or pneumonia [10]. Appropriate radiographic imaging, bronchoscopy, and a high level of clinical suspicion are essential for avoiding a misdiagnosis and inappropriate clinical management of these rare neoplasms of the lung. Complete surgical resection remains the primary treatment for MEC.

MEC of the lung may be surgically treated by lobectomy, sleeve resection, local resection, segmental resection, or even endoscopic removal [11]. Uniportal video-assisted thoracoscopic surgery for MEC was reported in an adult case [12], but there have been no previous reports on thoracoscopic lobectomy for pediatric MEC cases. This report is the first regarding a case of thoracoscopic surgery for pediatric MEC. In our case, severe adhesion after pneumonia obstructed the procedure. An early diagnosis is required to prevent disease progression and adhesion after pneumonia, which helps ensure safe thoracoscopic surgery. Pediatric MEC after complete resection does not need neoadjuvant chemotherapy, and the 5- and 10-year overall survival and disease-free survival rates were all 100 %.

We confirmed that there was no injury to the middle lobe bronchus and no residual tumor in the proximal trachea based on bronchoscopic findings before transecting the right upper bronchus. MEC of the tracheobronchial tree sometimes requires sleeve resection. Intraoperative bronchoscopy helped determine the exact position of the tumor. Avanzizni et al. [13] reported the value of intraoperative bronchoscopy for sparing the lung parenchyma and preserving as much of the respiratory function as possible.

4. Conclusion

We report the first case of thoracoscopic surgery for pediatric MEC, which is extremely rare. Intraoperative bronchoscopy should be actively performed in cases of pediatric lobectomy, especially those involving tracheobronchial tumors.

Abbreviations

MEC

mucoepidermal carcinoma

RUL

right upper lobectomy

Ethical approval

Ethical approval was provided by the authors' institution.

Funding

This research did not receive any specific grant from agencies in the public, commercial or not-for-profit sectors.

Author contribution

All authors are in agreement with the content of the article. Nanako Nishida, Shun Onishi and Satoshi Ieiri contributed to the operation. Masakazu Murakami, Mitsuru Muto and Takafumi Kawano contributed to data acquisition and interpretation. Nanako Nishida and Shun Onishi drafted the manuscript. Shun Onishi and Satoshi Ieiri approved the final version of the manuscript and agreed to be accountable for all aspects of the work in ensuring that questions related to the accuracy or integrity of any part of the work are appropriately investigated and resolved.

Guarantor

Satoshi Ieiri has accepted full responsibility for this work and the decision to publish it.

Research registration number

Research was registered at the National Clinical Database.

Declaration of competing interest

All authors declare that they do not have any conflicts of interest.

Appendix A. Supplementary data

The following is the supplementary data related to this article.

Supporting Video 1

Operative procedure.

The video shows the operative findings and procedure of resection for the right upper lobe using ICG and intraoperative bronchoscopy.