Pleuropulmonary Blastoma in Pediatric Lung Lesions

Patient Characteristics, Treatment, and Survival in Pleuropulmonary Blastoma: An Analysis from the National Cancer Database

Pleuropulmonary blastoma (PPB) is a rare childhood tumor originating from the lung or pleura, typically treated with surgery, chemotherapy (CTx), and/or radiation therapy (RTx). This study aimed to assess patient and tumor features, treatment methods, and survival rates in PPB. We retrospectively analyzed PPB patients under 18 from 2004 to 2019, using the National Cancer Database (NCDB). We assessed 5-year overall survival (OS) rates based on disease presentation and treatment regimens, using Kaplan-Meier curves and Cox proportional regression. Among 144 cases identified, 45.9% were female, with a median age of 2 years (interquartile range 1-3). In all, 62.5% of tumors originated from the lung, and 10.4% from the pleura. Moreover, 6.9% were bilateral, and the median tumor size was 8.9 cm, with 4.2% presenting with metastases. The 5-year OS rate was 79.6%, with no significant change over time (2004-2009, 77.6%; 2010-2014, 90.8%; 2015-2019, OS 75.3%; p = 0.08). In all, 5.6% received CTx alone, 31.3% surgery alone, 45.8% surgery/CTx, and 17.4% surgery/CTx/RTx. The OS rates were comparable between the surgery/CTx/RTx (80.0%) and surgery/CTx (76.5%) groups (adjusted Hazard Ratio, 1.72; 95% CI, 0.57-5.19; p = 0.34). Therefore, due to the unchanged survival rates over time, further prospective multicenter studies are needed to determine the optimal multimodal treatment regimens for this rare pediatric tumor.

No Pathogenic DICER1 Gene Variants in a Cohort Study of 28 Children With Congenital Pulmonary Airway Malformation

BACKGROUND

Distinguishing congenital pulmonary airway malformations (CPAMs) from pleuropulmonary blastoma (PPB) can be challenging. Previously diagnosed patients with CPAM may have been misdiagnosed and we may have missed DICER1-associated PPBs, a diagnosis with important clinical implications for patients and their families. To gain insight in potential misdiagnoses, we systematically assessed somatic DICER1 gene mutation status in an unselected, retrospective cohort of patients with a CPAM diagnosis.

METHODS

In the Amsterdam University Medical Center (the Netherlands), it has been standard policy to resect CPAM lesions. We included all consecutive cases of children (age 0-18 years) with a diagnosis of CPAM between 2007 and 2017 at this center. Clinical and radiographic features were reviewed, and DICER1 gene sequencing was performed on DNA retrieved from CPAM tissue samples.

RESULTS

Twenty-eight patients with a surgically removed CPAM were included. CPAM type 1 and type 2 were the most common subtypes (n = 12 and n = 13). For 21 patients a chest CT scan was available for reassessment by two pediatric radiologists. In 9 patients (9/21, 43%) the CPAM subtype scored by the radiologists did not correspond with the subtype given at pathology assessment. No pathogenic mutations and no copy number variations of the DICER1 gene were found in the DNA extracted from CPAM tissue (0/28).

CONCLUSIONS

Our findings suggest that the initial CPAM diagnoses were correct. These findings should be validated through larger studies to draw conclusions regarding whether systematic DICER1 genetic testing is required in children with a pathological confirmed diagnosis of CPAM or not.

LEVEL OF EVIDENCE

Level IV.

Prenatal Measurements of Congenital Lung Malformations: Can They Predict Postnatal Size?

INTRODUCTION

Prenatally diagnosed congenital lung malformations (CLMs) are monitored via ultrasound and measured by congenital pulmonary airway malformation volume ratios (CVRs) which can predict postnatal respiratory symptoms. This study compared CVR to postnatal lesion size to help guide prenatal counseling.

METHODS

A retrospective chart review evaluated the prenatal imaging and postnatal outcomes for patients who were prenatally diagnosed with CLMs and had a postnatal computed tomography (CT) scan at one institution.

RESULTS

Fifty-seven patients were included. Four had symptoms requiring urgent resection. The remaining were discharged and had clinic follow-up with CT scan to determine next steps: five had no identified lesions, eight had lesions whose diagnosis did not warrant an operation, and 40 had lesions whose diagnosis rendered size a factor in operative decision-making. Of these 40, 26/40 patients (65%) underwent elective resection (median maximum CVR 0.97; median lesion size 4 cm) and 14/40 patients (35%) were observed without resection (median maximum CVR 0.5; median lesion size 3 cm). There was a positive correlation between prenatal CVR and postnatal lesion size, with R-squared = 0.46. Maximum CVRs were better than last CVRs when predicting whether postnatal CT size would fall above or below our institution's level of recommended resection, with an area under the curve of 0.85 and a CVR cut-point of 0.61.

CONCLUSIONS

For newborns with asymptomatic CLMs, higher maximum CVRs correlated with larger size on postnatal CT. A maximum CVR ≤0.6 was correlated with a smaller postnatal CT size that may be eligible for nonoperative management. While these results are not intended to recommend surgery based on higher CVRs alone, this information could potentially be used to reassure expectant parents whose babies' prenatal imaging demonstrate lower maximum CVRs.

Sublobar Pulmonary Resection in Children With Congenital Lung Abnormalities: A Systematic Review

BACKGROUND

Lobectomy is currently the advised resection for symptomatic congenital lung abnormalities (CLA). Sublobar surgery is suggested as an alternative that enables to conserve healthy lung parenchyma. This systematic review aims to explore the outcomes of sublobar surgery in CLA patients as well as the corresponding surgical terminology and techniques.

METHODS

A systematic literature search was performed in adherence to PRISMA-P guidelines. The target population consists of children undergoing sublobar pulmonary resection for CLA. All studies were independently assessed by two reviewers, and evaluated by a third reviewer in case of disagreement.

RESULTS

The literature search yielded 901 studies of which 18 studies were included, comprising 1167 cases. The median chest tube insertion duration was 3.6 days (range 2.0-6.9 days), the median hospital admission was 4.9 days (range 2.0-14.5 days), and residual disease was diagnosed in 2% - leading to re-operation in 70%. The median incidence of postoperative complications was 15% (range 0-67%). Follow-up imaging was standard-of-care in 2/3 of studies. Due to the absence of standardised terminology, operative details and specification of resection type did not typically relate between studies.

CONCLUSIONS

Sublobar resection of CLA lesions could be a viable alternative to lobectomy in certain cases, with the advantage of conserving healthy lung parenchyma. Peri- and postoperative complications are comparable with those reported for conventional lobectomy. The incidence of residual disease following sublobar surgery appears to be lower than commonly stated. To improve comparability between studies, we recommend reporting perioperative characteristics in a structured format.

LEVEL OF EVIDENCE

Level IV.

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.

Maternal Steroids in High-Risk Congenital Lung Malformations

INTRODUCTION

The purpose of the present study is to evaluate our institutional management of high-risk congenital lung malformations (CLM) with particular consideration of the use of multiple maternal steroid courses and maternal steroids in CLMs with pathologies other than congenital pulmonary airway malformation (CPAM).

METHODS

A single-center retrospective review was performed for all fetuses evaluated for CLM who received maternal steroids and/or had a CLM volume ratio (CVR) ≥ 1.6 (2015-2020). Fetuses were categorized as receiving no steroids, single steroid, or multiple steroid courses. Outcomes evaluated included CVR growth rate, resolution of early hydrops, and resolution of hydrops. Results are reported with a descriptive analysis.

RESULTS

Nineteen patients were identified who had CVR ≥ 1.6 (single steroid course 9/19, multiple steroid courses 6/19, and no steroids 4/19). A majority (n = 13, 68%) of all lesions had a reduction or no change in CVR between initial and final measurements (single steroid course 7/9, 78%; multiple steroid courses 4/6, 67%). When evaluating by pathology, ≥ 50% of each classification had reduction or no growth of CVR (CPAM 7/11, bronchial atresia 2/4, sequestration 3/3, congenital lobar emphysema 1/1). Seventy five percent (3/4) of lesions with early hydrops had resolution following steroid treatment (single steroid course 1, multiple steroid courses 2). Of the four lesions that had hydrops, only one had resolution after receiving multiple steroid courses.

CONCLUSIONS

Our institutional experience reports the majority of CLM (including pathologies other than CPAM) who received steroids had reduction or no change in CVR. Given the low risk-benefit ratio of maternal steroids, physicians could consider use of multiple steroid courses for CLM refractory to a single course.

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.

A single institution's experience with the management of peripheral bronchial atresia

PURPOSE

Peripheral bronchial atresia is a pulmonary abnormality diagnosed on postnatal computed tomography after prenatal imaging reveals a congenital lung lesion. Debate regarding management of this abnormality prompted us to review our institution's practice patterns and outcomes.

METHODS

All patients diagnosed with bronchial atresia were assessed from 6/2014 to 7/2020. Pediatric radiologists were surveyed to delineate computed tomography criteria used to diagnose peripheral bronchial atresia. Criteria were applied in an independent blinded review of postnatal imaging. Data for patients determined to have peripheral bronchial atresia and at least an initial pediatric surgical evaluation were analyzed.

RESULTS

Twenty-eight patients with bronchial atresia received at least an initial pediatric surgical evaluation. Expectant management was planned for 22/28 (79%) patients. Two patients transitioned from an expectant management strategy to an operative strategy for recurrent respiratory infections; final pathology revealed bronchial atresia in both. Six patients were initially managed operatively; final pathology revealed bronchial atresia (n = 3) or congenital lobar overinflation (n = 3).

CONCLUSIONS

Peripheral bronchial atresia can be safely managed expectantly. A change in symptoms is suspicious for alternate lung pathology, warranting further workup and consideration for resection.

LEVEL OF EVIDENCE

Level IV.

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.