Lung Cancer Surgery in Partial Anomalous Pulmonary Venous Connection Patients

Lung cancer with partial anomalous pulmonary venous connection in a different lobe: a case report

Background

Anomalous pulmonary venous connection (APVC) is a congenital malformation in which the pulmonary veins connect to the systemic venous system but not to the left atrium. APVC can be classified as total or partial (PAPVC). PAPVC is rare among surgical patients with lung cancer, and most cases are detected incidentally during surgery. We herein report a patient with lung cancer in whom PAPVC was diagnosed before surgery, which made it difficult to determine the surgical procedure.

Case presentation

A 71-year-old man was followed-up as an outpatient after surgery for renal cell carcinoma. Chest computed tomography showed a 22-mm nodule in the right lower lobe and PAPVC in the right upper lobe. He was diagnosed with lung adenocarcinoma (cT1cN0M0 stage IA3) and scheduled for surgery. Preoperative catheterization showed a pulmonary to systemic flow ratio (Qp/Qs) of 1.64 and mean pulmonary artery pressure (MPAP) of 16 mmHg. Surgical repair of PAPVC is indicated when a patient is symptomatic and has a Qp/Qs ≥1.5–2.0. The patient was scheduled for right lower lobectomy, but postoperative worsening of right heart strain was considered. Concomitant PAPVC repair was therefore considered, but he had no atrial septal defect and was asymptomatic; therefore, PAPVC treatment was considered unnecessary. However, we planned to perform concomitant PAPVC repair if his circulatory dynamics worsened during surgery or if his MPAP exceeded 25 mmHg. His MPAP was 20 mmHg and his circulatory dynamics remained stable, and right lower lobectomy was therefore completed. His postoperative course was favorable. Follow-up catheterization at 6 months showed a Qp/Qs of 1.19 and MPAP of 18 mmHg, with no evidence of increased right heart strain. There was no evidence of right heart failure or recurrence of lung cancer at last follow-up at 18 months after surgery.

Conclusions

We present a case of right lower lung cancer complicated by PAPVC in the right upper lobe. This case suggests that concomitant repair of PAPVC in the right upper lobe may not be necessary when performing right lower lobectomy, although the patient’s Qp/Qs and MPAP should be considered.

Identifying partial anomalous pulmonary venous connection in the superior vena cava before pulmonary resection

OBJECTIVE

There are only limited reports on pulmonary resection complicated with partial anomalous pulmonary venous connection. Preoperative partial anomalous pulmonary venous connection was overlooked in approximately 50% of these reports, while most cases of were located on the same side as the pulmonary resection. We examined the prevalence of overlooked partial anomalous pulmonary venous connection and determined appropriate measures to avoid misdiagnosis.

METHODS

We retrospectively reviewed the records and computed tomography data of consecutive patients who underwent pulmonary resection at the University of Yamanashi Hospital between 2006 and 2019. We re-evaluated the computed tomography images in horizontal and coronal views, focusing on the four common sites of partial anomalous pulmonary venous connection. Further, we conducted a literature review of studies that reported partial anomalous pulmonary venous connection cases.

RESULTS

Among the 1389 patients who underwent pulmonary resection, 1205 were enrolled. There were five partial anomalous pulmonary venous connection cases (0.41%). Two were diagnosed through re-evaluation. The partial anomalous pulmonary venous connection was located between the right upper lobe and the superior vena cava in four patients (80%). All patients underwent left superior segmentectomy, and none experienced postoperative heart failure or hypoxia. In the literature, the incidence rates of partial anomalous pulmonary venous connection observed by computed tomography (0.1-0.25%) were lower than those observed by autopsy (0.62%) and angiography (0.82%).

CONCLUSION

There may be a considerable number of overlooked partial anomalous pulmonary venous connection cases. Therefore, particularly the superior vena cava should be carefully monitored in preoperative computed tomography examinations.

Partial anomalous pulmonary venous connection detected during right pneumonectomy

Partial anomalous pulmonary venous connection (PAPVC) is a rare congenital anomaly. Generally, it is seen on the right side and is associated with an atrial septal defect. Herein, we present a case of a 50-year-old male patient with a supracardiac type PAPVC detected during pneumonectomy for a right hilar mass. This is the second case report in the literature presenting surgical treatment of both lung cancer and PAPVC using pneumonectomy. Thoracic surgeons should be aware of this anomaly when they are planning to perform a major lung resection. If PAPVC and lung cancer are in the same lobe, anatomical lung resections including pneumonectomy can be safely performed.

Anomalous right upper lobe pulmonary veins draining posterior to the pulmonary artery

The anatomy of pulmonary vessels varies. The right upper pulmonary vein usually drains in front of the pulmonary artery to the left atrium. We herein describe a case of the right upper lobe pulmonary vein draining posterior to the pulmonary artery and absent right upper lobe pulmonary vein in the ventral hilum. A 64-year-old woman suspected to have lung cancer and scheduled for surgery underwent pre-operative three-dimensional computed tomography (3D-CT), which revealed that pulmonary vessels V1 + 3 and V2 drain posteriorly to the pulmonary artery. Video-assisted right upper lobectomy was performed because the patient was diagnosed with lung adenocarcinoma through intraoperative pathologic analysis, and all the pulmonary vessels were identified correctly during the operation. Despite the limited surgical field of video-assisted lobectomy, the operation was performed safely because the pre-operative 3D-CT assessment revealed the anatomy of the anomalous pulmonary vessels, helping us avoid missing any anomaly and vessel injury.