Combined approach for a left pneumonectomy and carinal reconstruction

Abstract

Tumor involving the carina is a real challenge to thoracic surgeons due to the complexity of airway reconstruction and management. Carinal resection is a safe procedure in highly selected patients with acceptable morbidity and mortality and good long-term survival. A 32-year-old lady with adenoid cystic carcinoma arising from the left main bronchus underwent carinal pneumonectomy using a combined thoracotomy and midline sternotomy approach without the use of cardiopulmonary bypass.

Introduction

Carinal pneumonectomy is one of the challenging procedures in thoracic surgery [1]. The two major types of malignant salivary gland type tumors in pulmonary location are adenoid cystic carcinoma and mucoepidermoid carcinoma [2]. This report describes a patient with adenoid cystic carcinoma of the left main bronchus who underwent successfully left carinal pneumonectomy, using a combined thoracotomy and midline sternotomy approach without the use of cardiopulmonary bypass.

Case study

A 32-year-old lady presented with chronic cough and dyspnea for 1 year and a complete collapse of the left lung with left mediastinal shift on chest X-ray (Fig. 1A). Computed tomography (CT) scan showed an endobronchial tumor of 4-cm size in the left main bronchus with no nodal or extranodal metastasis (Fig. 1B). Positron emission tomography (PET) CT revealed metabolically active primary in the left main bronchus with no significant mediastinal lymphadenopathy or distant metastasis. Videobronchoscopic biopsy was reported as moderately differentiated squamous cell carcinoma (Fig. 2A).

Fig. 1.

A Preoperative chest X-ray showing lesion in the left main bronchus (blue arrow). B Preoperative CT of the chest showing tumor mass in the left main bronchus (red arrow)

Fig. 2.

A Videobronchoscopy showing endobronchial tumor completely obstructing the left main bronchus. B Postoperative CT of the chest volume rendering showing no anastomotic leak or narrowing

The patient was intubated with a double-lumen tube to the right main bronchus. Vascular control of the left lung with dissection of the left main bronchus and lymph node was done through left posterolateral thoracotomy. Hard mass was felt in the left main bronchus and the carina was not accessible through thoracotomy. So it was decided to do a median sternotomy to assess the operability. The carina and the right main bronchus were free of tumor. The left main bronchus was divided from the carina and the edge was sent for a frozen section which showed positive margins.

Hence, carinal resection and trachea to right main bronchus anastomosis was decided. The carina was resected with 2 rings of tracheal cartilage after release of anterior and posterior aspects of the trachea. The endotracheal tube was pulled back and the right lung was ventilated with sterile cross-field flexometallic tube ventilation. Trachea to right main bronchus end-end anastomosis was completed using 4–0 prolene with continuous suture on the posterior membranous wall and interrupted suture on the cartilaginous wall. The anastomosis was covered with a vascularized flap of pericardial fat. Left pneumonectomy was completed through left thoracotomy approach. Chin stitches were placed to keep the neck in flexed position postoperatively which were removed after 10 days.

The patient was weaned from the ventilator after confirming airway patency with fiberoptic bronchoscopy. There was a small residual pneumothorax which was treated conservatively. The postoperative period was uneventful except for hoarseness of voice due to left vocal cord palsy which subsequently recovered. Histopathological examination of the resected specimen showed features of adenoid cystic carcinoma of the left main bronchus with high-grade transformation (40% solid pattern), peribronchial lymph node involvement, and no extranodal extension, pathological stage classification—pT2aN1Mx. Postoperative CT of the chest revealed no evidence of anastomotic leak or narrowing of the anastomosis of the right main bronchus to trachea (Fig. 2B). The patient recovered well and was discharged on 15th postoperative day. During follow-up review 2 weeks after surgery, she was tolerating diet orally with no respiratory symptoms or signs of infection.

Discussion

Adenoid cystic carcinoma is a rare, low-grade, slow-growing salivary gland–type malignant epithelial neoplasm, with rare involvement of the tracheobronchial tree, accounting for 0.04–0.2% of lung tumors [3, 4]. It occurs in 4^th–5^th decade of life with no sex predilection or relationship with tobacco smoking [3]. Usual presentation is endobronchial lesions due to submucosal bronchial gland origin giving rise to symptoms such as cough, dyspnea, hemoptysis, and recurrent infections [3]. The main factors affecting the long-term outcome are complete surgical resection and no nodal involvement [5], so appropriate patient selection is important. Preoperative workup includes a cardiopulmonary assessment with disease extension and nodal status assessments by CT of the chest, bronchoscopy, and PET CT scan. Hematoxylin–eosin staining and immunohistochemistry study is the method used for the diagnosis of adenoid cystic carcinoma with three architectural growth patterns: cribriform, tubular, and solid [6] and dual cell type differentiation (Fig. 2B). The solid pattern is more aggressive and prone to early distant metastasis.

The first comprehensive approach to carinal resection and reconstruction was presented by Hermes C. Grillo and co-workers in 1963 and by Grillo in 1982 [1]. Different surgical approaches described for left carinal pneumonectomy include left thoracotomy, bilateral thoracotomy, clamshell approach, and median sternotomy [5]. Due to advancements in minimal access thoracic surgery, left pneumonectomy can also be completed using video-assisted thoracoscopic surgery (VATS) or robotic surgery [5]. Median sternotomy is the preferred approach for left carinal resection because of excellent exposure of the tracheobronchial bifurcation and less incisional discomfort, which results in less ventilatory restriction than thoracotomy [5].

Disadvantages of the sternotomy approach include difficulty in freeing pleuroparietal adhesions, mobilization of the left hilum requires cardiac retraction which may cause some hemodynamic instability, and difficult pneumonectomy as the access to the left thoracic cavity is limited [7]. Avoid devascularization of the trachea and main bronchi, to make a good-quality anastomosis, and to have healthy resection margins [7]. Surgical resection of adenoid cystic carcinoma of the left main bronchus can be performed safely without the use of cardiopulmonary bypass.

Author contribution

Dr. Nainar Madhu Sankar, Dr. Robert Coelho, Dr. Gopal Murugesan, Dr. Noveen Davidson, Dr. Mridula Manikandan, and Dr. Sezhiyan Thandavarayan contributed equally to this work.

Funding

None.

Declarations

Ethical approval

Ethical approval obtained.

Informed consent

Informed consent obtained.

Statement of human and animal rights

It is confirmed that the study was performed in accordance with the ethical standards as laid down in the 1964 Declaration of Helsinki and its later amendments or comparable ethical standards.

Conflict of interest

We have no conflict of interest to disclose.