Congenital lung malformations: an ongoing controversy

Management and Outcomes of Patients With High-Risk (Congenital Lung Malformation Volume Ratio≥ 1.6) Congenital Lung Malformations

INTRODUCTION

Congenital lung malformations (CLMs) have a variable natural history. Larger lesions with CLM volume ratio (CVR) ≥ 1.6 are associated with hydrops and fetal mortality. The purpose of this study is to describe the management and outcomes of high-risk (CVR ≥ 1.6) CLM patients.

METHODS

A retrospective cohort study was performed for all fetuses evaluated between May 2015 and May 2022. Demographics, prenatal imaging factors, prenatal and postnatal treatment, and outcomes were collected. Descriptive statistics were used to compare the cohorts.

RESULTS

Of 149 fetal CLM patients referred to our fetal center, 21/149 (14%) had CVR ≥ 1.6. One CLM patient had intrauterine fetal demise, and 2 patients were lost to follow-up. Of the remaining 18 patients, 11/18 (67%) received maternal steroids. Seven out of 18 patients (39%) underwent resection at the time of delivery with 1/7 (14%) undergoing exutero intrapartum treatment (EXIT)-to-resection, 5/7 (71%) undergoing EXIT-to-exteriorization-to-resection, and 1/7 (14%) undergoing a coordinated delivery to resection; among those undergoing resection, there were 2 fatalities (28.5%). Seven out of 18 (39%) patients required urgent neonatal open lobectomies, and the remaining 4/18 (22%) patients underwent elective thoracoscopic lobectomies with no mortality.

CONCLUSIONS

The natural history and outcomes of severe CLM patients remain highly variable. The EXIT-to-exteriorization-to-resection procedure may be a safe and effective approach for a subset of CLM patients with persistent symptoms of mass effect and severe mediastinal shift due to the observed decreased operative time requiring placental support observed in our study.

Selection of potential targets for stratifying congenital pulmonary airway malformation patients with molecular imaging: is MUC1 the one?

Currently there is a global lack of consensus about the best treatment for asymptomatic congenital pulmonary airway malformation (CPAM) patients. The somatic KRAS mutations commonly found in adult lung cancer combined with mucinous proliferations are sometimes found in CPAM. For this risk of developing malignancy, 70% of paediatric surgeons perform a resection for asymptomatic CPAM. In order to stratify these patients into high- and low-risk groups for developing malignancy, a minimally invasive diagnostic method is needed, for example targeted molecular imaging. A prerequisite for this technique is a cell membrane bound target. The aim of this study was to review the literature to identify potential targets for molecular imaging in CPAM patients and perform a first step to validate these findings.A systematic search was conducted to identify possible targets in CPAM and adenocarcinoma in situ (AIS) patients. The most interesting targets were evaluated with immunofluorescent staining in adjacent lung tissue, KRAS+ CPAM tissue and KRAS- CPAM tissue.In 185 included studies, 143 possible targets were described, of which 20 targets were upregulated and membrane-bound. Six of them were also upregulated in lung AIS tissue (CEACAM5, E-cadherin, EGFR, ERBB2, ITGA2 and MUC1) and as such of possible interest. Validating studies showed that MUC1 is a potential interesting target.This study provides an extensive overview of all known potential targets in CPAM that might identify those patients at risk for malignancy and conducted the first step towards validation, identifying MUC1 as the most promising target.

Clinical Symptoms Affect Treatment and Prognosis in Pediatric Patients with Congenital Pulmonary Airway Malformation: A Propensity Score Matching Retrospective Cohort Study

OBJECTIVES

Surgery for asymptomatic congenital pulmonary airway malformation patients is still debatable at this time. This study aims to investigate the safety and efficacy of surgery for asymptomatic patients, as well as the factors influencing the symptoms of this group of patients.

METHODS

An institutional database was sampled for congenital pulmonary airway malformation patients. Patients were divided into the symptomatic group and the asymptomatic group. Propensity score matching (PSM) analysis selected patients in each group to compare perioperative outcomes. A multivariable logistic regression analysis was performed to investigate the potential influences on symptomatic lesions.

RESULTS

The asymptomatic group had better perioperative results than the symptomatic group, including shorter operating times (119.39 ± 49.42 min vs 100.73 ± 23.09 min, P = 0.031), shorter postoperative mechanical ventilation (2 h [0.5-46] vs 1 h [0.5-5], P = 0.002), shorter chest tube durations (4d [2-29] vs 3d [2-10], P = 0.007), and shorter postoperative hospital stays (10d [6-36] vs 8d [6-16], P < 0.001). With the conversion to thoracotomy and postoperative complications, there was no statistically significant difference between the two PSM-matched groups (P > 0.05). Age (p = 0.037), postnatal diagnosis (p = 0.018), and maximum cyst diameter (p = 0.032) were found to be independent variables associated with symptomatic lesions by multivariable logistic regression.

CONCLUSIONS

Patients with congenital pulmonary airway malformation appear to have better perioperative outcomes before the beginning of symptoms. Symptomatic pulmonary lesions were associated with age, postnatal diagnosis, and maximum cyst diameter.

LEVEL OF EVIDENCE

Level III.

Initial experience of thoracoscopic segmentectomy of basal segment through the inferior pulmonary ligament approach in treating congenital lung malformations in children

PURPOSE

This study aimed to evaluate the feasibility and limitations of thoracoscopic segmentectomy of the basal segment (S10).

METHODS

Clinical data of 15 children with congenital lung malformations (CLM) who underwent thoracoscopic segmentectomy of S10 via the inferior pulmonary ligament approach from January to October 2022 were retrospectively analyzed. The demographics, clinical presentation, intraoperative time, blood loss, postoperative events, and follow-up duration were assessed.

RESULTS

There were 15 patients in this group (nine males and six females). Age ranges from 4.3 to 96.0 months (median, 7.7 months). Fourteen patients underwent S10 segmentectomy, with one undergoing right S10 segmentectomy and right S6 partial wedge resection. The surgical time was 57-125 min (median, 80 min), intraoperative bleeding volume (5-20 ml; median, 10 ml), postoperative drainage tube indwelling (2-4 d; median, 3 d), and postoperative hospitalization time (4-7 d; median, 5 d). No intraoperative conversions, surgical mortalities, or major complications were observed among these patients. Subcutaneous emphysema appeared in three patients; however, it disappeared following conservative observation without pneumothorax or bronchopleural fistula occurrence.

CONCLUSIONS

Thoracoscopic segmentectomy of S10 via the inferior pulmonary ligament approach is technically feasible for treating CLM; however, this surgical approach may have certain limitations for CLM with large cysts.

Congenital lung abnormalities on magnetic resonance imaging: the CLAM study

OBJECTIVES

Follow-up of congenital lung abnormalities (CLA) is currently done with chest computer tomography (CT). Major disadvantages of CT are exposure to ionizing radiation and need for contrast enhancement to visualise vascularisation. Chest magnetic resonance imaging (MRI) could be a safe alternative to image CLA without using contrast agents. The objective of this cohort study was to develop a non-contrast MRI protocol for the follow-up of paediatric CLA patients, and to compare findings on MRI to postnatal CT in school age CLA patients.

METHODS

Twenty-one CLA patients, 4 after surgical resection and 17 unoperated (mean age 12.8 (range 9.4-15.9) years), underwent spirometry and chest MRI. MRI was compared to postnatal CT on appearance and size of the lesion, and lesion associated abnormalities, such as hyperinflation and atelectasis.

RESULTS

By comparing school-age chest MRI to postnatal CT, radiological appearance and diagnostic interpretation of the type of lesion changed in 7 (41%) of the 17 unoperated patients. In unoperated patients, the relative size of the lesion in relation to the total lung volume remained stable (0.9% (range - 6.2 to + 6.7%), p = 0.3) and the relative size of lesion-associated parenchymal abnormalities decreased (- 2.2% (range - 0.8 to + 2.8%), p = 0.005).

CONCLUSION

Non-contrast-enhanced chest MRI was able to identify all CLA-related lung abnormalities. Changes in radiological appearance between MRI and CT were related to CLA changes, patients' growth, and differences between imaging modalities. Further validation is needed for MRI to be introduced as a safe imaging method for the follow-up of paediatric CLA patients.

KEY POINTS

• Non-contrast-enhanced chest MRI is able to identify anatomical lung changes related to congenital lung abnormalities, including vascularisation. • At long-term follow-up, the average size of congenital lung abnormalities in relation to normal lung volume remains stable. • At long-term follow-up, the average size of congenital lung abnormalities associated parenchymal abnormalities such as atelectasis in relation to normal lung volume decreases.

COllaborative Neonatal Network for the first European CPAM Trial (CONNECT): a study protocol for a randomised controlled trial

INTRODUCTION

Consensus is lacking on the optimal management of asymptomatic congenital pulmonary airway malformation (CPAM). For future studies, the CONNECT consortium (the COllaborative Neonatal Network for the first European CPAM Trial)-an international collaboration of specialised caregivers-has established consensus on a core outcome set of outcome parameters concerning respiratory insufficiency, surgical complications, mass effect and multifocal disease. These outcome parameters have been incorporated in the CONNECT trial, a randomised controlled trial which, in order to develop evidence-based practice, aims to compare conservative and surgical management of patients with an asymptomatic CPAM.

METHODS AND ANALYSIS

Children are eligible for inclusion after the CPAM diagnosis has been confirmed on postnatal chest CT scan and they remain asymptomatic. On inclusion, children are randomised to receive either conservative or surgical management. Subsequently, children in both groups are enrolled into a standardised, 5-year follow-up programme with three visits, including a repeat chest CT scan at 2.5 years and a standardised exercise tolerance test at 5 years.The primary outcome is exercise tolerance at age 5 years, measured according to the Bruce treadmill protocol. Secondary outcome measures are molecular genetic diagnostics, validated questionnaires-on parental anxiety, quality of life and healthcare consumption-, repeated imaging and pulmonary morbidity during follow-up, as well as surgical complications and histopathology. This trial aims to end the continuous debate surrounding the optimal management of asymptomatic CPAM.

ETHICS AND DISSEMINATION

This study is being conducted in accordance with the Declaration of Helsinki. The Medical Ethics Review Board of Erasmus University Medical Centre Rotterdam, The Netherlands, has approved this protocol (MEC-2022-0441). Results will be disseminated through peer-reviewed scientific journals and conference presentations.

TRIAL REGISTRATION NUMBER

NCT05701514.

Does Timing of Resection Influence the Presence of Inflammation within Congenital Lung Malformations?

INTRODUCTION

 Opinion remains divided on whether to resect an asymptomatic congenital lung malformation (CLM) and on optimal timing of resection. This study aimed to determine if age at resection of CLM correlates with the presence of histological inflammation and/or incidence of prior antibiotic administration for lower respiratory tract infection (LRTI).

MATERIALS AND METHODS

 A retrospective review of all CLMs resected between 2009 and 2021 was carried out. Data on antenatal detection, incidence of preoperative antibiotic use for LRTI, operative details, and histological reports were analyzed. Fisher's exact test and logistic regression were used to look for correlation between age at resection and (1) histological inflammation and/or (2) preoperative LRTI.

RESULTS

 A total of 102 patients underwent resection at age 14 months (interquartile range: 6-23). Eighty percent of children were asymptomatic in the neonatal period and 22% of these went on to develop a respiratory symptom. In total, 59% of specimens had histological evidence of inflammation, with a significantly higher rate of inflammation after 10 months of age (71 vs. 35%; p = 0.0012). Logistic regression showed there was a positive correlation between age at resection and treatment for previous LRTI (p = 0.020).

CONCLUSION

 Detection rates of inflammation in specimens resected after 10 months of age are double the rates of those resected prior to 10 months. Delaying resection of CLMs showed a higher frequency of treatment of LRTI. Earlier resection may therefore be advantageous for centers pursuing a resection strategy for asymptomatic lesions.

Should asymptomatic patients with congenital lung malformations undergo surgery? A decision analysis

BACKGROUND

Congenital lung malformations (CLMs) are being detected more frequently during pregnancy. There is controversy regarding the optimal treatment for an asymptomatic child with prenatally diagnosed CLMs. Due to the paucity of information from clinical trials, we developed decision analytic models to compare two treatment strategies for such patients-elective surgical resection versus expectant management.

METHODS

We built decision analytic models stratified by lesion size. We used data from English language literature identified through PubMed searches along with estimates from expert opinions of surgical colleagues. We analyzed results for two hypothetical asymptomatic 6-month-old children with CLMs; one has a large lesion occupying more than 50% of the involved lobe, while the other has a small lesion occupying less than 50% of the involved lobe. We used quality-adjusted life years (QALYs) to measure effectiveness.

RESULTS

For an asymptomatic child with a small or large lesion, expectant management resulted in a small gain of 0.09 or 0.15 QALYs, respectively. Sensitivity analyses showed that surgical resection would be preferred if the probability of remaining asymptomatic was low.

CONCLUSIONS

In contrast to current practice, expectant management may be a better alternative for asymptomatic children born with CLMs. More longitudinal studies are required to improve the accuracy of the model.

Long-Term Results of Pediatric Congenital Pulmonary Malformation: A Population-Based Matched Case-Control Study with a Mean 7-Year Follow-Up

Symptomatic congenital pulmonary malformations (CPMs) are a group of anomalies involving the lungs. The long-term outcomes of these patients are not well known. The present research aimed to study the pulmonary function, respiratory morbidity, and health-related quality of life (QoL) of patients treated for CPMs. All children (<16 years of age) treated for CPMs in 2002−2012 (in Oulu University Hospital) were invited to the follow-up visit. Altogether, there were 22 patients, out of which 17 (77%) participated. The mean follow-up time was 6.6 (ranged from 3 to 16) years. Pulmonary function tests, diffusing capacity, respiratory morbidity, and QoL were determined as the primary outcomes. Potential residual malformations and lung anatomy were investigated using computer tomography (CT) imaging. The outcomes were compared to the age- and sex-matched healthy controls. The forced expiratory volume at 1 s (FEV1, Z-score) remained lower in operated patients compared to the healthy controls (−1.57 ± SD 1.35 vs. −0.39 ± SD −0.86, p-value 0.005). There were no differences in respiratory morbidity or QoL between the patients and the controls. The surgical approach (lobectomy vs. partial resection) did not affect lung function. A younger age (<1 year of age) at the time of the surgery seemed to result in a higher lung capacity, but the finding was not statistically significant. Patients with CPMs treated with surgery were satisfied with their wellbeing in the long-term. A lower lung function did not have an impact on their wellbeing. However, there was a slight decrease in lung function compared to the healthy controls, and a clinical follow-up of the patients was recommended.

Quantitative CT imaging analysis to predict pathology features in patients with a congenital pulmonary airway malformation

BACKGROUND

Risk for infection and potential malignant degeneration are the most common arguments for resecting asymptomatic Congenital Pulmonary Airway Malformations (CPAM). We aimed to investigate if CT- imaging characteristics can be used to predict histopathological features, by using an objective quantitative CT scoring method.

METHODS

Archival CPAM tissue samples were histologically re-assessed and patients who had a pre-operative volumetric CT-scan were included. Lung disease was quantified using the newly-developed congenital lung abnormality quantification(CLAQ) scoring method and obtained percentages were used to predict histopathological signs of inflammation and presence of mucinous proliferation (MP). Because MP is presumed a precursor for mucinous adenocarcinoma in situ (AIS) this method was also used to compare CT-scans of patients with AIS to those with only CPAM.

RESULTS

Thirty-three CPAM patients were included of which 13(39%) had histological signs of inflammation and 8(24%) had a MP. Patients with inflammation had a significantly smaller lesion (14% vs 38%) while those with MP had more extensive disease (54%vs17%). Patients with AIS had a significantly smaller lesion compared to CPAM patients (5%vs29%). Significant predictors for inflammation were smaller lesion size and percentage hypodensity within lesions while a larger lesion size and percentage parenchymal hyperdensity (solid lung tissue components) were predictors for MP as well as AIS.

CONCLUSIONS

Smaller CPAM lesions may be more susceptible to inflammation while larger lesions may be associated with the presence of MP. Parenchymal hyperdensity is found as a predictor for MP as well as AIS and should therefore elicit more extensive gross sampling.

LEVEL OF EVIDENCE

Level III.

The Management of Asymptomatic Congenital Pulmonary Airway Malformation: Results of a European Delphi Survey

Consensus on the optimal management of asymptomatic congenital pulmonary airway malformation (CPAM) is lacking, and comparison between studies remains difficult due to a large variety in outcome measures. We aimed to define a core outcome set (COS) for pediatric patients with an asymptomatic CPAM. An online, three-round Delphi survey was conducted in two stakeholder groups of specialized caregivers (surgeons and non-surgeons) in various European centers. Proposed outcome parameters were scored according to level of importance, and the final COS was established through consensus. A total of 55 participants (33 surgeons, 22 non-surgeons) from 28 centers in 13 European countries completed the three rounds and rated 43 outcome parameters. The final COS comprises seven outcome parameters: respiratory insufficiency, surgical complications, mass effect/mediastinal shift (at three time-points) and multifocal disease (at two time-points). The seven outcome parameters included in the final COS reflect the diversity in priorities among this large group of European participants. However, we recommend the incorporation of these outcome parameters in the design of future studies, as they describe measurable and validated outcomes as well as the accepted age at measurement.

The Role of Hypoxia in Improving the Therapeutic Potential of Mesenchymal Stromal Cells. A Comparative Study From Healthy Lung and Congenital Pulmonary Airway Malformations in Infants

Mesenchymal stromal cells (MSCs) play an important role in the field of regenerative medicine thanks to their immunomodulatory properties and their ability to secrete paracrine factors. The use of MSCs has also been tested in children with congenital lung diseases inducing fibrosis and a decrease in lung function. Congenital malformations of the pulmonary airways (CPAM) are the most frequently encountered lung lesion that results from defects in early development of airways. Despite the beneficial properties of MSCs, interventions aimed at improving the outcome of cell therapy are needed. Hypoxia may be an approach aimed to ameliorate the therapeutic potential of MSCs. In this regard, we evaluated the transcriptomic profile of MSCs collected from pediatric patients with CPAM, analyzing similarities and differences between healthy tissue (MSCs-lung) and cystic tissue (MSCs-CPAM) both in normoxia and in cells preconditioned with hypoxia (0.2%) for 24 h. Study results showed that hypoxia induces cell cycle activation, increasing in such a way the cell proliferation ability, and enhancing cell anaerobic metabolism in both MSCs-lung and MSCs-CPAM-lung. Additionally, hypoxia downregulated several pro-apoptotic genes preserving MSCs from apoptosis and, at the same time, improving their viability in both comparisons. Finally, data obtained indicates that hypoxia leads to a greater expression of genes involved in the regulation of the cytoskeleton in MSCs-lung than MSCs-CPAM.

Accuracy of Chest Computed Tomography in Distinguishing Cystic Pleuropulmonary Blastoma From Benign Congenital Lung Malformations in Children

IMPORTANCE

The ability of computed tomography (CT) to distinguish between benign congenital lung malformations and malignant cystic pleuropulmonary blastomas (PPBs) is unclear.

OBJECTIVE

To assess whether chest CT can detect malignant tumors among postnatally detected lung lesions in children.

DESIGN, SETTING, AND PARTICIPANTS

This retrospective multicenter case-control study used a consortium database of 521 pathologically confirmed primary lung lesions from January 1, 2009, through December 31, 2015, to assess diagnostic accuracy. Preoperative CT scans of children with cystic PPB (cases) were selected and age-matched with CT scans from patients with postnatally detected congenital lung malformations (controls). Statistical analysis was performed from January 18 to September 6, 2020. Preoperative CT scans were interpreted independently by 9 experienced pediatric radiologists in a blinded fashion and analyzed from January 24, 2019, to September 6, 2020.

MAIN OUTCOMES AND MEASURES

Accuracy, sensitivity, and specificity of CT in correctly identifying children with malignant tumors.

RESULTS

Among 477 CT scans identified (282 boys [59%]; median age at CT, 3.6 months [IQR, 1.2-7.2 months]; median age at resection, 6.9 months [IQR, 4.2-12.8 months]), 40 cases were extensively reviewed; 9 cases (23%) had pathologically confirmed cystic PPB. The median age at CT was 7.3 months (IQR, 2.9-22.4 months), and median age at resection was 8.7 months (IQR, 5.0-24.4 months). The sensitivity of CT for detecting PPB was 58%, and the specificity was 83%. High suspicion for malignancy correlated with PPB pathology (odds ratio, 13.5; 95% CI, 2.7-67.3; P = .002). There was poor interrater reliability (κ = 0.36 [range, 0.06-0.64]; P < .001) and no significant difference in specific imaging characteristics between PPB and benign cystic lesions. The overall accuracy rate for distinguishing benign vs malignant lesions was 81%.

CONCLUSIONS AND RELEVANCE

This study suggests that chest CT, the current criterion standard imaging modality to assess the lung parenchyma, may not accurately and reliably distinguish PPB from benign congenital lung malformations in children. In any cystic lung lesion without a prenatal diagnosis, operative management to confirm pathologic diagnosis is warranted.

SARS-CoV-2 Exposed Mesenchymal Stromal Cell from Congenital Pulmonary Airway Malformations: Transcriptomic Analysis and the Expression of Immunomodulatory Genes

The inflammatory response plays a central role in the complications of congenital pulmonary airway malformations (CPAM) and severe coronavirus disease 2019 (COVID-19). The aim of this study was to evaluate the transcriptional changes induced by SARS-CoV-2 exposure in pediatric MSCs derived from pediatric lung (MSCs-lung) and CPAM tissues (MSCs-CPAM) in order to elucidate potential pathways involved in SARS-CoV-2 infection in a condition of exacerbated inflammatory response. MSCs-lung and MSCs-CPAM do not express angiotensin-converting enzyme 2 (ACE2) and transmembrane serine protease 2 (TRMPSS2). SARS-CoV-2 appears to be unable to replicate in MSCs-CPAM and MSCs-lung. MSCs-lung and MSCs-CPAM maintained the expression of stemness markers MSCs-lung show an inflammatory response (IL6, IL1B, CXCL8, and CXCL10), and the activation of Notch3 non-canonical pathway; this route appears silent in MSCs-CPAM, and cytokine genes expression is reduced. Decreased value of p21 in MSCs-lung suggested no cell cycle block, and cells did not undergo apoptosis. MSCs-lung appears to increase genes associated with immunomodulatory function but could contribute to inflammation, while MSCs-CPAM keeps stable or reduce the immunomodulatory receptors expression, but they also reduce their cytokines expression. These data indicated that, independently from their perilesional or cystic origin, the MSCs populations already present in a patient affected with CPAM are not permissive for SARS-CoV-2 entry, and they will not spread the disease in case of infection. Moreover, these MSCs will not undergo apoptosis when they come in contact with SARS-CoV-2; on the contrary, they maintain their staminality profile.

Morbidity after thoracoscopic resection of congenital pulmonary airway malformations (CPAM): single center experience over a decade

PURPOSE

Video-assisted thoracoscopic (VATS) resection of CPAM in children is an established, albeit controversial strategy for its management. We report a 10-year single center experience.

METHODS

All children underwent VATS (2008-2017) and their current status was reviewed. Patients were grouped: 'symptomatic-P' (if parents reported recurrent lower respiratory tract infections etc.) or 'symptomatic-S' (neonates presenting with respiratory distress/difficulty) or 'asymptomatic'.

RESULTS

73 children, aged 10 m (4d-14yrs) underwent VATS; a neonate as an emergency ('symptomatic-S') and all others electively. The lesion was unilateral in all but one case. Histologically none were malignant. Of the elective 72 cases, 7 (10%) required conversion to open thoracotomy. Twenty (27.7%) were 'symptomatic-P' and the duration of surgery when compared to 'asymptomatic' children was longer 269 (range 129-689) versus 178 (range 69-575) minutes (P = 0.01). Post operatively, 8 children (11%) had a grade III/IV (Clavien-Dindo) complication; persistent air leak/pneumothorax (n = 5), chylothorax (n = 1), pleural effusion (n = 1) and seizure/middle cerebral artery thrombosis (n = 1). There was no mortality. Twenty-four children (33.3%) were reported 'symptomatic-P' post-surgery after a median follow up of 2.18 years. The surgical intervention had no impact on 'symptomatic-P' status (P = 0.46).

CONCLUSION

The risks of surgery may outweigh benefit in asymptomatic children. CLINICALTRIALS.

GOV IDENTIFIER

NCT04449614.

Pleuropulmonary Blastoma in Pediatric Lung Lesions

BACKGROUND

Pediatric lung lesions are a group of mostly benign pulmonary anomalies with a broad spectrum of clinical disease and histopathology. Our objective was to evaluate the characteristics of children undergoing resection of a primary lung lesion and to identify preoperative risk factors for malignancy.

METHODS

A retrospective cohort study was conducted by using an operative database of 521 primary lung lesions managed at 11 children's hospitals in the United States. Multivariable logistic regression was used to examine the relationship between preoperative characteristics and risk of malignancy, including pleuropulmonary blastoma (PPB).

RESULTS

None of the 344 prenatally diagnosed lesions had malignant pathology (P < .0001). Among 177 children without a history of prenatal detection, 15 (8.7%) were classified as having a malignant tumor (type 1 PPB, n = 11; other PPB, n = 3; adenocarcinoma, n = 1) at a median age of 20.7 months (interquartile range, 7.9-58.1). Malignancy was associated with the DICER1 mutation in 8 (57%) PPB cases. No malignant lesion had a systemic feeding vessel (P = .0427). The sensitivity of preoperative chest computed tomography (CT) for detecting malignant pathology was 33.3% (95% confidence interval [CI]: 15.2-58.3). Multivariable logistic regression revealed that increased suspicion of malignancy by CT and bilateral disease were significant predictors of malignant pathology (odds ratios of 42.15 [95% CI, 7.43-340.3; P < .0001] and 42.03 [95% CI, 3.51-995.6; P = .0041], respectively).

CONCLUSIONS

In pediatric lung masses initially diagnosed after birth, the risk of PPB approached 10%. These results strongly caution against routine nonoperative management in this patient population. DICER1 testing may be helpful given the poor sensitivity of CT for identifying malignant pathology.

A case report of an unusual non-mucinous papillary variant of CPAM type 1 with KRAS mutations

Background

congenital pulmonary airway malformation (CPAM) is the most frequent congenital lung disorder. CPAM type 1 is the most common subtype, typically having a cystic radiological and histological appearance. Mucinous clusters in CPAM type 1 have been identified as premalignant precursors for mucinous adenocarcinoma. These mucinous adenocarcinomas and the mucinous clusters in CPAM commonly harbor a specific KRAS mutation.

Case presentation

we present a case of a 6-weeks-old girl with CPAM type 1 where evaluation after lobectomy revealed a highly unusual complex non-mucinous papillary architecture in all cystic parts, in which both mucinous clusters and non-mucinous papillary areas harbored the known KRAS mutation.

Conclusions

we found that a KRAS mutation thought to be premalignant in mucinous clusters only, was also present in the other cyst lining epithelial cells of this unusual non-mucinous papillary variant of CPAM type 1, warranting clinical follow-up because of uncertain malignant potential.

Structural and perfusion magnetic resonance imaging of congenital lung malformations

BACKGROUND

A radiation-free advanced imaging modality is desirable for investigating congenital thoracic malformations in young children.

OBJECTIVE

To describe magnetic resonance imaging (MRI) findings of congenital bronchopulmonary foregut malformations and investigate the ability of lung MRI for their classification.

MATERIALS AND METHODS

This is a retrospective analysis of consecutive MRI examinations performed for suspected congenital lung anomalies in 39 children (median age: 3.8 months, range: 2 days-15 years). Morphological and perfusion findings were characterised on respiratory-gated fast spin echo and dynamic contrast-enhanced sequences obtained at 1.5 tesla. Abnormalities were classified independently by two readers and compared to an expert diagnosis based on pathology, surgery and/or other imaging.

RESULTS

Main diagnoses included bronchopulmonary lesions in 33 patients, scimitar syndrome in 4 patients, pulmonary arteriovenous malformation and oesophageal duplication cyst in one patient each. Of 46 observed abnormalities, 44 (96%) were classified correctly with very good interobserver agreement (96% concordance rate). The 39 detected lung lesions included isolated overinflation (17/39, 44%), cystic pulmonary airway malformation (8/39, 21%), bronchopulmonary sequestration (7/39, 18%), bronchogenic cyst (4/39, 10%) and hybrid lesion (3/39, 8%). All lung lesions presented as perfusion defect at peak pulmonary enhancement. Non-cystic lesions showed a delayed peak (median delay: 2.8 s, interquartile range: 0.5 to 4.0 s) in relation to normal lung parenchyma.

CONCLUSION

A dedicated lung MRI protocol including respiratory compensated sequences, dynamic angiography and perfusion is able to reliably delineate parenchymal and vascular components of congenital bronchopulmonary foregut malformations. Therefore, MRI may be considered for comprehensive postnatal evaluation of congenital thoracic malformations.

Asymptomatic Congenital Lung Malformations: Timing of Resection Does Not Affect Adverse Surgical Outcomes

Background: Optimal timing for resection of asymptomatic congenital lung malformations (CLMs) remains controversial. The aim of this study is to define optimal timing for surgical intervention of patients with CLMs and define clinical variables that affect surgical outcomes. Methods: An IRB-approved retrospective analysis was conducted for patients undergoing surgery for CLMs between 2012 and 2017. Subjects were divided into cohorts based on timing of operative intervention. "Early intervention" was defined as surgery within 4 months of birth; "intermediate intervention"-between 4 and 6 months; and "late intervention"-6-12 months. Surgical outcomes including intraoperative estimated blood loss (EBL), surgical time, post-operative pneumothorax, length of time chest tube stayed in, and hospital length of stay were compared among the three groups using Fisher's exact test or Chi-squared test for categorical variables and one-way analysis of variance test for continuous variables. Results: We analyzed 63 patients who underwent surgery for CLM. There were no significant differences in baseline characteristics. Timing of surgery did not significantly correlate with post-operative outcomes. Specifically, there was no difference in operative time, EBL, post-operative pneumothorax, or length of hospital stay among the early, intermediate, and late intervention groups. Even after controlling for cyst-volume ratio (CVR), timing of surgery still did not affect post-operative outcomes. Conclusions: Surgical outcomes for resection of CLMs are not significantly affected by timing of surgery. We advocate for early intervention to decrease the incidence of associated complications that can occur with later intervention.

Pediatric Pulmonology Year in Review 2018: Rare lung disease, neuromuscular disease, and diagnostic testing

Pediatric Pulmonology publishes original research, case reports, and review articles on topics related to a wide range of children's respiratory disorders. In this article, we highlight the past year's publications in the topic areas of rare lung diseases, respiratory complications of neuromuscular disorders, and diagnostic testing, as well as selected literature in these areas from other journals.

Agreement between magnetic resonance imaging and computed tomography in the postnatal evaluation of congenital lung malformations: a pilot study

OBJECTIVES

To compare postnatal magnetic resonance imaging (MRI) with the reference standard computed tomography (CT) in the identification of the key features for diagnosing different types of congenital lung malformation (CLM).

METHODS

Respiratory-triggered T2-weighted single-shot turbo spin echo (ss-TSE), respiratory-triggered T1-weighted turbo field echo (TFE), balanced fast field echo (BFFE), and T2-weighted MultiVane sequences were performed at 1.5 T on 20 patients prospectively enrolled. Two independent radiologists examined the postnatal CT and MRI evaluating the presence of cysts, hyperinflation, solid component, abnormal arteries and/or venous drainage, and bronchocele. Diagnostic performance of MRI was calculated and the agreement between the findings was assessed using the McNemar-Bowker test. Interobserver agreement was measured with the kappa coefficient.

RESULTS

CT reported five congenital pulmonary airway malformations (CPAMs), eight segmental bronchial atresias, five bronchopulmonary sequestrations (BPS), one congenital lobar overinflation, one bronchogenic cyst, and three hybrid lesions. MRI reported the correct diagnosis in 19/20 (95%) patients and the malformation was correctly classified in 22/23 cases (96%). MRI correctly identified all the key findings described on the CT except for the abnormal vascularization (85.7% sensitivity, 100% specificity, 100% PPV, 94.1% NPV, 95% accuracy for arterial vessels; 57.1% sensitivity, 100% specificity, 100% PPV, 84.2% NPV, 87% accuracy for venous drainage).

CONCLUSIONS

MRI can represent an effective alternative to CT in the postnatal assessment of CLM. In order to further narrow the gap with CT, the use of contrast material and improvements in sequence design are needed to obtain detailed information on vascularization, which is essential for surgical planning.

KEY POINTS

• Congenital lung malformations (CLMs) can be effectively studied by MRI avoiding radiation exposure. • Crucial features of CLM have similar appearance when comparing CT with MRI. • MRI performs very well in CLM except for aberrant vessel detection and characterization.

Asymptomatic congenital lung malformations: Is nonoperative management a viable alternative?

INTRODUCTION

The purpose of this study was to evaluate clinical outcomes in children with asymptomatic congenital lung malformations (CLM) who were initially managed nonoperatively.

METHODS

An IRB-approved retrospective review was performed on all CLMs at a single tertiary care referral center (Jan 2006-Dec 2016, n=140). Asymptomatic cases that did not undergo elective resection were evaluated for subsequent CLM-related complications based on clinical records and a telephone quality of life survey.

RESULTS

Out of 39 (27.9%) who were initially managed nonoperatively, 13 (33%) developed CLM-related symptoms and underwent surgical intervention at a median age of 6.8years (range, 0.7-19.8years). The most common indication for conversion to operative management was pneumonia (78%). Larger lesions, as measured by CT scan, were significantly associated with the need for subsequent surgical intervention (mean maximal diameter, 5.7 vs. 2.9cm; p=0.005). Based on survey data with a median follow up of 3.9years (range, 0.2-13.2years), 17% developed chronic pulmonary symptoms, including cough (11%) and asthma requiring bronchodilators (12%).

CONCLUSION

Although these data support nonoperative management as a viable alternative to surgical resection, at least one-third of CLM children eventually develop pneumonia or other pulmonary symptoms. Larger lesions are correlated with an increased risk for eventual surgical resection.

LEVEL OF EVIDENCE

Level IV.

Decision-Making Criteria for Observational Management of Congenital Pulmonary Airway Malformations (CPAMs)

PURPOSE

The purpose of this study was to determine practice patterns of Canadian surgeons managing congenital pulmonary airway malformations (CPAMs) and factors influencing practice.

METHODS

Pediatric surgeons in Canada were surveyed regarding their experience, evaluation, and management CPAMs, and what factors they feel qualify patients for observation vs resection. Data were summarized, and Fisher's-Exact and Kruskal-Wallis Tests applied where appropriate.

RESULTS

Sixty eight percent (n=46) of surgeons responded. However, three surveys were incomplete and excluded. The median age of initial assessment by a pediatric surgeon was one month. 98% (42/43) use CXR for initial imaging, and 83% (36/43) recommend CT scan for further evaluation. Observation is offered always, almost always, or sometimes by 2%, 35% and 37%, respectively. Only 16% almost never, and 9% never offer it. Years in practice was not associated with this decision (p=0.41). Of surgeons who offer observation, 78% (28/37) use morphology to guide their decision, and 63% (21/37) use lesion size (<1cm to <5cms). 68%(23/37) consider the number of lesions, and 61%(14/23) of those only offer observation to solitary lesions.

CONCLUSION

Most pediatric surgeons in Canada offer observational management to patients with asymptomatic CPAMs. While practice variations exist, detailed imaging with a CT scan early in life to determine the morphology, size, and number of lesions guides practice.

LEVEL OF EVIDENCE

V.

Treatment of congenital pulmonary airway malformations: a systematic review from the APSA outcomes and evidence based practice committee

PURPOSE

Variation in management characterizes treatment of infants with a congenital pulmonary airway malformation (CPAM). This review addresses six clinically applicable questions using available evidence to provide recommendations for the treatment of these patients.

METHODS

Questions regarding the management of a pediatric patient with a CPAM were generated. English language articles published between 1960 and 2014 were compiled after searching Medline and OvidSP. The articles were divided by subject area and by the question asked, then reviewed and included if they specifically addressed the proposed question.

RESULTS

1040 articles were identified on initial search. After screening abstracts per eligibility criteria, 130 articles were used to answer the proposed questions. Based on the available literature, resection of an asymptomatic CPAM is controversial, and when performed is usually completed within the first six months of life. Lobectomy remains the standard resection method for CPAM, and can be performed thoracoscopically or via thoracotomy. There is no consensus regarding a monitoring protocol for observing asymptomatic lesions, although at least one chest computerized tomogram (CT) should be performed postnatally for lesion characterization. An antenatally identified CPAM can be evaluated with MRI if fetal intervention is being considered, but is not required for the fetus with a lesion not at risk for hydrops. Prenatal consultation should be offered for infants with CPAM and encouraged for those infants in whom characteristics indicate risk of hydrops.

CONCLUSIONS

Very few articles provided definitive recommendations for care of the patient with a CPAM and none reported Level I or II evidence. Based on available information, CPAMs are usually resected early in life if at all. A prenatally diagnosed congenital lung lesion should be evaluated postnatally with CT, and prenatal counseling should be undertaken in patients at risk for hydrops.

CPAM type 2-derived mesenchymal stem cells: Malignancy risk study in a 14-month-old boy

INTRODUCTION

The association between congenital pulmonary airway malformations (CPAM) and malignancy is reported in the literature. Interactions between the tumor, immune, and mesenchymal stromal/stem cells (MSCs) have been recognized as crucial for understanding tumorigenesis. We characterized MSCs isolated from CPAM lesions in order to define potential malignancy risks.

METHODS

CPAM II pulmonary tissue was used for MSC expansion; a "healthy" lung section from the same child was used as a comparator. Morphology, immunophenotype, differentiation and immunological capacity, proliferative growth, gene signature telomerase activity, and in vivo tumorigenicity in nude mice were evaluated.

RESULTS

MSCs were successfully isolated and propagated from CPAM tissue. CPAM-MSCs presented the typical MSC morphology and phenotype, while exhibiting high proliferative capacity, reaching confluence at a median time of 5 days as well as differentiation capabilities. CPAM-MSCs at early passages were not neoplastic and chromosomally normal, even though unbalanced chromosomal rearrangements were noted by molecular karyotype.

CONCLUSIONS

CPAM-MSCs exhibited specific features similar to tumor derived MSCs. Whilst there was no evidence of malignant transformation in the cystic tissue, our results provide evidence that this abnormal tissue has malignant potential. MSCs are considered important players in the tumor microenvironment and they have been closely linked to regulation of tumor survival, growth, and progression. Thus, early lesion resection also in asymptomatic patients might be indicated to exclude that the microenvironment may be potentially permissive to cancer development.

Anatomical Segmentectomy with a Hybrid VATS Approach in a Patient with Intralobar Pulmonary Sequestration after Severe Pneumonia: A Case Report

Anatomical segmentectomy is an advantageous procedure because it spares healthy lung that has potential to show compensatory growth after lung resection and decreases the risk of air leak and residual resection, which becomes a problem in wedge resection. However, anatomical segmentectomy has not become a common procedure in pediatrics because it requires more complicated procedure than lobectomy or wedge resection, especially in patients with a history of pulmonary infection. In this case report, anatomical basal segmentectomy was safely performed with magnified vision by a hybrid video-assisted thoracic surgery (VATS) approach in a 6-year-old girl with intralobar pulmonary sequestration after severe pneumonia. The result suggests that the indications for hybrid VATS segmentectomy can expand further to include segmental lesions in children.

Resection of pediatric lung malformations: National trends in resource utilization & outcomes

PURPOSE

We sought to determine factors influencing survival and resource utilization in patients undergoing surgical resection of congenital lung malformations (CLM). Additionally, we used propensity score-matched analysis (PSMA) to compare these outcomes for thoracoscopic versus open surgical approaches.

METHODS

Kids' Inpatient Database (1997-2009) was used to identify congenital pulmonary airway malformation (CPAM) and pulmonary sequestration (PS) patients undergoing resection. Open and thoracoscopic CPAM resections were compared using PSMA.

RESULTS

1547 cases comprised the cohort. In-hospital survival was 97%. Mortality was higher in small vs. large hospitals, p<0.005. Survival, pneumothorax (PTX), and thoracoscopic procedure rates were higher, while transfusion rates and length of stay (LOS) were lower, in children ≥3 vs. <3months (p<0.001). Multivariate analysis demonstrated longer LOS for older patients and Medicaid patients (all p<0.005). Total charges (TC) were higher for Western U.S., older children, and Medicaid patients (p<0.02). PSMA for thoracoscopy vs. thoracotomy in CPAM patients showed no difference in outcomes.

CONCLUSION

CLM resections have high associated survival. Children <3months of age had higher rates of thoracotomy, transfusion, and mortality. Socioeconomic status, age, and region were independent indicators for resource utilization. Extent of resection was an independent prognostic indicator for in-hospital survival. On PSMA, thoracoscopic resection does not affect outcomes.

Surgical versus conservative management of congenital pulmonary airway malformation in children: A systematic review and meta-analysis

BACKGROUND

The ideal management of infants born with asymptomatic congenital pulmonary airway malformation (CPAM) is controversial. We performed a systematic review and meta-analysis comparing elective resection versus expectant management.

METHODS

We searched CENTRAL, MEDLINE, EMBASE, CINAHL, and PubMed for studies describing the management of asymptomatic CPAM and reporting on postoperative morbidity, mortality, and length of hospital stay (LOS). We performed meta-analyses when possible and provide a narrative summary of results.

RESULTS

One nonrandomized prospective and eight retrospective studies met our inclusion criteria. Out of 168 patients, 70 underwent surgery before symptoms developed with seven experiencing postoperative complications (10.0%); 63 developed symptoms while being managed expectantly and subsequently underwent surgery with 20 complications (31.8%). Thirty-five patients continued to be followed nonsurgically (three months to nine years of follow-up). Morbidity was higher with surgery after symptom development (6 studies; odds ratio 4.59, 95% confidence interval (CI) 1.40 to 15.11, P<0.01); there was no difference in LOS (3 studies; mean difference 4.96, 95% CI -1.75 to 11.67, P=0.15). There were no related deaths.

CONCLUSIONS

Elective resection of asymptomatic CPAM lesions is safe and prevents the risk of symptom development, which may result in a more complicated surgery and recovery.

Surgical intervention strategies for pediatric congenital cystic lesions of the lungs: A 20-year single-institution experience

BACKGROUND

The aim of this study was to assess surgical intervention strategies for congenital cystic lesions of the lungs (CCL), focusing on the safety of lung resection.

MATERIALS AND METHODS

The clinical features of 27 children (CCAM, n=16; bronchial atresia, n=4; bronchogenic cyst, n=3; pulmonary sequestration, n=3; lobar emphysema, n=1) who were treated at our institution between 1995 and 2014 were analyzed.

RESULTS

Of the 27 patients, 14 were asymptomatic, and 13 were symptomatic. The youngest symptomatic patient presented with pneumonia at 9months of age. The mean age at surgery was 4months in the asymptomatic group and 4.1years in the symptomatic group. The mean operating time was 167minutes in the asymptomatic group and 275minutes in the symptomatic group (P<0.001). The mean amount of intraoperative bleeding was 15g in the asymptomatic group and 83.4g in the symptomatic group (P<0.05). All of the prenatally diagnosed patients underwent surgery within six months of birth. Three patients had remnant cystic lesions, all of which involved cystic lesions located over the lobulation anomalies of the lung.

CONCLUSIONS

To minimize surgical invasiveness, surgery for CCL should be performed during the asymptomatic period or within six months after birth.

The argument for a non-operative approach to asymptomatic lung lesions

The controversy surrounding the management of congenital lung malformations (CLMs) centre on how best to manage the increasing population of asymptomatic antenatally detected infants. Should elective surgery be offered? Or is a "watch-and-wait" policy safe? This will be addressed in this review by examining the reported complications of surgery, the risk of symptom development if lesions are left in situ and whether this may alter surgical outcomes, and importantly whether there is any long-term risk of malignancy that can be negated by surgical resection in infancy.

Antenatally diagnosed lung malformations: a plea for long-term outcome studies

There is a wide variation in the management of infants with antenatally diagnosed lung malformations, with many paediatric surgeons and respiratory paediatricians recommending early investigations for all infants and a surgical excision for the majority of lesions, while others favour a conservative management for all asymptomatic infants. The benefits and risks of a surgical intervention have to be compared with the natural history of the untreated malformation and cohort studies from foetal diagnosis to adult life are required to provide the relevant evidence. Careful and repeated surveillance of identified foetuses is essential as recent advances in foetal medicine and surgery have improved the outcomes for the small minority, who are at risk of developing hydrops.

Congenital lung malformations: informing best practice

The management of congenital lung malformations is controversial both in the prenatal and postnatal periods. This article attempts to inform best practice by reviewing the level of evidence with regard to prenatal diagnosis, prognosis, and management and postnatal management, including imaging, surgical indication, surgical approach, and risk of malignancy. We present a series of clinically relevant statements along those topics and analyze the evidence for each. In the end, we make a plea for an adequate description of the lesions, both before and after birth, which will allow future comparisons between management options and the initiation of prospective registries.