4. Discussion
In light of improvements in antenatal ultrasound diagnosis, an increased number of fetuses are diagnosed with CCAM in utero. In this study, 23 patients were diagnosed with CCAM through prenatal sonography, with a diagnosis rate of up to 96% (23/24). Most CCAMs are not associated with severe respiratory symptoms after birth, but approximately 10% of lung lesions, including CCAMs, will present with symptoms during the neonatal period 8. Infection is the most common presenting symptom, as indicated by the patients in this study. Other symptoms include shortness of breath, respiratory distress, and mediastinal deviation. The optimal timing for the resection of asymptomatic CCAM remains controversial, but surgery is the accepted standard for all symptomatic CCAMs 9,10, and thoracoscopic operations are safe and feasible, even in neonates11,12. After the infection subsided sufficiently, we performed surgical treatment of symptomatic CCAM patients.
This study shows that both thoracoscopic and open resection for symptomatic CCAM have achieved good clinical outcomes in the neonatal period. When the two surgical methods are compared under the same preoperative conditions, thoracoscopic resection results in a shorter surgical incision and less operative blood loss, but the operation time is longer. Therefore, thoracoscopic surgery achieved an esthetic effect consistent with minimally invasive surgery. These clinical results are similar to those described in the literature4,13,14. In our experience, neonatal CCAM has a clear boundary with normal lung tissue and no adhesions caused by repeated infections. The blood vessels and bronchial tubes are relatively small and can be directly cut off by an ultrasonically activated scalpel. These characteristics are conducive to thoracoscopic resection. Thoracoscopic resection of CCAM has one unfavorable factor: the operation space is small, making it difficult to perform this operation during the neonatal period. Prior to this, we performed thoracoscopic operations for congenital diaphragmatic hernia and extralobar pulmonary sequestration to improve our skills. In addition, when suturing is difficult, a 3-mm trocar can also be added to assist. If blood oxygen maintenance is unstable during the operation, it is necessary to temporarily stop the operation and stop the artificial pneumothorax.
The extent of surgical resection in the management of CCAM also remains controversial 15. Muller, CO et al.16 state that adequate treatment of CCAM in children requires lobectomy because of poor sensitivity and very poor negative predictive value of preoperative CT for determining distal adjacent lesions. Laberge JM et al.6 think that Lobectomy is recommended in order to prevent postoperative air leaks, residual disease, and perhaps reduce the risk of some later malignancies. Fascetti-Leon, F. et al.17 state that lung-sparing surgery for congenital lung malformations is a safe and effective method of lung parenchymal preservation in pediatric patients. If accurately planned in selected patients, lung-sparing surgery does not carry a higher risk of residual disease and recurrence than traditional lobectomy. Kim, HK et al.18 report that the early and late outcomes were excellent even after parenchyma-saving resection in patients with CCAM, and suggest that parenchyma-saving resection can be safely performed in selected patients with a well-confined CCAM lesion and thereby avoiding lobectomy.
In this study, twenty patients underwent a lung-preserving wedge resection strategy for the treatment of CCAM of the lower lobe. Four patients underwent lobectomy because the CCAM almost completely occupied the upper or middle lobe. One early patient had the postoperative complication of an air leaks, which was cured by continuous thoracic drainage. We think that this complication was caused by poor wound healing rather than a problem with the lung preservation strategy because there was no recurrence in the postoperative follow-up. It may also have been related to unskilled suturing under thoracoscopy at an early stage of the procedure, but the complication rate was not statistically significantly different from that of open resection (P=1).
In conclusion, based on the data and follow-up results of this study, we believe that thoracoscopic resection is a safe and favorable approach for treating symptomatic CCAM of the lung in neonates. Compared with open resection, thoracoscopic surgery has minimal esthetic effects and does not increase the risk of surgical or postoperative complications. The lung-preserving resection strategy is feasible for neonatal CCAM patients. However, the study results are limited because of the small number of cases. In the next step, we will continue to perform long-term follow-up and evaluate the respiratory function of these patients.