Lobectomy for lung cancer in a patient with Fontan circulation: A case report.

A view of the surgical field after left upper lobectomy was performed.

A case of successful radical pulmonary lobectomy and lymphadenectomy for a lung cancer patient with Fontan circulation is presented.

See Commentary on page 166.

Clinical Summary

A 26-year-old man diagnosed with primary lung cancer of the left upper lobe was referred to our hospital. Contrast-enhanced computed tomography of the chest showed a mass in the anterior segment of the left upper lobe (Figure 1, A). No evidence of hilar and mediastinal lymphadenopathy or metastatic lesions was detected. Transbronchial lung biopsy of the mass at the referring hospital had already provided a histopathological diagnosis of adenocarcinoma. The clinical stage diagnosis cT2 bN0 M0 indicated surgical resection. His past history included a diagnosis of pulmonary atresia with intact ventricular septum at birth, a left modified Blalock-Taussig shunt (mBTS) placed in infancy, followed by total cavopulmonary connection (TCPC) at age 4 years (Figure 1, B). His exercise capacity was more than 5 metabolic equivalents, and his daily activities, including full-time work, were good when he visited our outpatient clinic. His baseline oxygen saturation was 96%. Lung function tests were good, with a forced vital capacity of 4.16 L and a forced expiratory volume in 1 second of 3.80 L. Echocardiogram showed no apparent arrhythmia or bundle branch block. The transthoracic echocardiogram showed the morphologic left ventricle supporting the systemic circulation with moderately reduced ejection fraction (44%) and a hypoplastic tricuspid valve and right ventricle. Contrast-enhanced computed tomography showed that the polytetrafluoroethylene graft used for the mBTS was occluded (Figure 1, C). A cardiac catheterization study showed that his mean pulmonary arterial pressure was 7 mm Hg and his pulmonary vascular resistance (PVR) was 1.32 Wood units/m2. Notably, a pulmonary perfusion scan showed that the perfusion was extremely right lung dominant, with a left–right ratio of 10:90 (Figure 1, D). Based on the preoperative cardiopulmonary evaluation, it was concluded that left upper lobectomy would have a minor effect on his Fontan circulation, and left upper lobectomy and lymphadenectomy were performed as radical surgery. Despite concern about hemodynamic impairment, 1-lung ventilation did not result in any major changes to pulmonary artery (PA) pressure, blood pressure, arterial oxygen saturation, or mixed venous oxygen saturation. Severe adhesions of the upper lobe to the chest wall and mediastinum were present because of previous surgery. In particular, the polytetrafluoroethylene graft used to create the mBTS had adhered densely to the left lung. The tumor had directly invaded the anterior chest wall and required extrapleural dissection around the tumor. There were no anatomic abnormalities, whereas the left PA was hypoplastic, and any branches diverging into the upper lobe were thinner than normal, consistent with the findings of the lung perfusion scan. The left main PA was extremely deviated and folded so that it was tractioned cranially below the aortic arch (Figure 2). It was believed that this was due to the PA being pulled cranially at the anastomosis because the polytetrafluoroethylene graft did not extend with growth (Video 1). The pathologic diagnosis was adenocarcinoma, pT3 (ie, parietal pleura invasion) N0 M0, pStage IIB. The postoperative course was uneventful. Six months after surgery, the patient is doing well without relapse of the cancer or cardiac symptoms. Consent was obtained from the patient to publish this work.

Figure 1

Contrast-enhanced computed tomography of the patient before surgery. A, A 5.5-cm mass adjacent to the anterior chest wall is seen in the left upper lobe. B, The polytetrafluoroethylene graft used for modified Blalock-Taussig shunt (arrow) from the left subclavian artery to the left pulmonary artery (PA) is occluded. C, The superior vena cava is anastomosed directly to the right PA, and the inferior vena cava is connected to the right PA via an intra-atrial lateral tunnel. D, Lung perfusion scan showing a left–right lung perfusion ratio of 10:90.

Figure 2

A view of the surgical field after left upper lobectomy. Severe adhesion around the modified Blalock–Taussig shunt (mBTS) is seen. At the anastomosis site of the shunt, the left pulmonary artery (PA) had been tractioned and deviated to the cranial side. Ao, Aorta; LLL, left lower lobe.

Radical pulmonary lobectomy for a lung cancer patient with Fontan circulation. mBTS, Modified Blalock-Taussig shunt; PA, pulmonary artery. Video available at: https://www.jtcvs.org/article/S2666-2507(20)30766-5/fulltext.

Discussion

Recently, the number of adult patients with Fontan circulation undergoing noncardiac surgery has increased due to improvements in surgical technique and medical management. However, many of the surgical procedures are less invasive, such as inguinal hernia repair and nasal sinus surgery. As for highly invasive surgery, only a few cases of hepatectomy for hepatocellular carcinoma due to cardiac cirrhosis have been reported. Pulmonary resection is still challenging for these patients. It causes a decrease in pulmonary vascular bed volume and consequently an increase in PVR, and there is a risk that the Fontan circulation will fail. Regarding pulmonary lobectomy, there have been only 2 cases reported. One was for pulmonary arteriovenous malformations and the other for pulmonary sequestration, both of which showed improvement in oxygenation and hemodynamic parameters postoperatively., As far as we are aware, this is the first case of successful radical resection for primary lung cancer in which the patient experienced subsequent minor functional loss. Although more than 20 years had passed since TCPC surgery, the patient's exercise capacity was very good, with a PVR of 1.32 U, well below the 4.0 U indicated for TCPC. Although pulmonary blood flow on the affected side was extremely low, quantitative magnetic resonance imaging analysis has been reported to show reduced left PA blood flow in TCPC patients. Therefore, it was judged that lobectomy could be performed safely, but the feasibility of lobectomy for adult patients with Fontan circulation should be carefully considered in the future.