Inflammatory myofibroblastic tumor of the lung: a rare cause of atelectasis in children.

Although rare, inflammatory myofibroblastic tumor is the most common primary lung mass in children. We report the case of an 11-year-old boy investigated for persistent cough and dyspnea with complete left lung atelectasis mimicking pneumonia. CT and MRI showed an endobronchial mass of the left main bronchus. The boy underwent endoscopic resection of the tumor and histology was in favor of an inflammatory myofibroblastic tumor of the lung. This diagnosis should be suspected in children with recurrent pneumonia. The prognosis is good after complete resection.

Airway obstruction in congenital central hypoventilation syndrome.

Congenital central hypoventilation syndrome (CCHS) is the failure of the autonomic system to control adequate ventilation while asleep with preserved ventilatory response while awake. We report a case of a patient with CCHS who presented with intrathoracic and extrathoracic airway obstruction after tracheostomy tube decannulation and phrenic nerve pacer placement. Nocturnal polysomnography (NPSG) revealed hypoxia, hypercapnia and obstructive sleep apnoea, which required bilevel positive airway pressure titration. Airway endoscopy demonstrated tracheomalacia and paretic true vocal cords in the paramedian position during diaphragmatic pacing. Laryngeal electromyography demonstrated muscular electrical impulses that correlated with diaphragmatic pacer settings. Thus, we surmise that the patient's upper and lower airway obstruction was secondary to diaphragmatic pacer activity. Thorough airway evaluation, including NPSG and endoscopy, may help identify the side effects of diaphragmatic pacing, such as airway obstruction, in patients with CCHS.

Dysanaptic growth of lung and airway in children with post-infectious bronchiolitis obliterans.

RATIONALE: Post-infectious bronchiolitis obliterans (PBO) is a rare form of chronic obstructive lung disease associated with small airway fibrosis following a severe insult to the lower respiratory tract. It has been suggested that PBO is a non-progressive disease. However, evidence supporting this statement is limited. In this case series, we sought to determine the changes of pulmonary function tests (PFT) over time in children with PBO. METHODS: Seven children with PBO, ages 6-15 years old, were retrospectively studied between 1994 and 2012. Spirometry and lung volumes tests were performed in accordance with American Thoracic Society (ATS) guidelines and were monitored over time. The average rate of change was calculated using generalized linear mixed models. RESULTS: The median baseline values for forced vital capacity (FVC), forced expiratory volume in 1 s (FEV1), the FEV1/FVC ratio and forced expiratory flow 25%-75% (FEF25%-75%) were 57%, 50%, 87% and 29%, respectively. FVC increased at a rate of 1.8% per year (P = 0.008). There was no significant change in FEV1 over time (P = 0.112). However, the FEV1/FVC ratio decreased by 2.6% per year (P < 0.001). CONCLUSION: PFT in childhood PBO was characterized by significant airway obstruction. Over time, FVC (lung parenchyma) increased and FEV1 (airway) remained stable, but FEV1/FVC ratio declined more than expected, suggesting a mismatch in the growth of the airway and lung parenchyma (dysanaptic growth). Further studies in larger populations are needed to validate these observations.

Radioresistance-related proteins in rectal cancer.

Radiation therapy (RT), combined with chemotherapy, is currently the standard adjuvant approach for UICC-stage II and III rectal cancer patients. Individual rectal tumors display wide ranges of radiosensitivity (RS). The aim of the present study was to identify proteins associated with radioresistance (RR), with the final aim of predicting tumor response. Seventeen patients were recruited between July 1998 and November 2001. All patients suffered from a locally advanced adenocarcinoma of the rectum. Tumor biopsies were taken before RT. All patients received preoperatively 50 Gray or a biologically equivalent total dose. Surgery was performed after 6 weeks, and response assessed histopathologically. Seven tumors showed complete response, seven a partial response, and in three patients only microscopic disease remained. Proteins were separated using narrow pH gradient two-dimensional polyacrylamide gel electrophoresis and silver staining. Automatic gel comparison allowed matching a mean number of 497 +/- 280 spots. Forty-four spots showing significant differential expression in RR tumors were localized on the pH 4.5-5.5 gels, 33 out of them being identified by matrix-assisted laser desorption/ionization-time of flight mass spectrometry. Twenty-two out of 37 spots of interest could be identified on the pH 5.5-6.7 gels. The expression of the following proteins correlates with RR: tropomodulin (p = 0.01), heat shock protein 42 (p = 0.03), beta-tubulin (p = 0.10), annexin V (p = 0.10), calsenilin (p = 0.10), or with radiosensitivity (RS): keratin type I (p = 0.03), notch 2 protein homolog (p = 0.05) and DNA repair protein RAD51L3 (p = 0.11). A further RR-related protein is so far only hypothetical: XP_030188 (NCBI Database accession number, p = 0.14). We consider the fact that several of these proteins of interest are known to be associated with RR as a valid proof of principle for this proteomics approach. These results will serve as a basis for developing an assay for testing rectal cancers for radioresistance.