[Childhood pleuropulmonary blastoma: a clinicopathologic study of 16 cases].

OBJECTIVE: To study the clinicopathological and immunohistochemical features, histogenesis and prognosis of pleuropulmonary blastoma (PPB) in children. METHODS: PPB specimens from 16 pediatric cases with an age ranging from 1 year and 7 months to 5 years and 3 months (mean age of 3 years) were retrieved and analyzed by routine histological, immunohistochemical and electron methods. RESULTS: Among 16 patients, there were 2 type I, 7 type II and 7 type III PPB cases. Type I PPB as multilocular cystic structure, consisted of thin fibrous wall lining the respiratory epithelium, subepithelial primitive blastema or immature mesenchymal cells, with or without rhabdomyoblastic differentiation or cartilage; Type II PPB as cystic-solid tumor, comparing with type I, consisted of intracystic components with appearance of anaplastic tumor cells. Type III PPB consisted of completely solid mass, the same as the solid region of type II, had mixed pattern including blastema, undifferentiated spindle-cell proliferations and sarcomas. In addition, anaplastic tumor cells and intra-and extra- cytoplasmic eosinophilic globules were also commonly present. Epithelial components in PPB were benign. Immunohistochemical study showed primitive mesenchymal differentiation of tumors. All cases were positive for vimentin, desmin, myogenin and SMA in tumors with skeletal muscle differentiation, S-100 was positive in tumors with cartilage differentiation. All tumors were negative for synaptophysin, CD99, and CD117. Benign epithelial components were positive for AE1/AE3 and EMA. In 12 cases, electron microscopy revealed few organelles in the primitive mesenchymal cells and rich heterochromatin in mesenchymal cells, the latter also demonstrating cytoplasmic myofilament dysplasia. Nine cases had clinical follow-up ranging from 5 to 48 months, of which 4 patients died. CONCLUSIONS: PPB is a rare lung neoplasm of children under the age of 6 years, with distinct pathological morphology. PPB may arise from lung or pleura mesenchymal cells and has a poor clinical outcome.

[Congenital intrapulmonary lymphangioma and pulmonary hemangioma in 5 infants and young children].

OBJECTIVE: To analyze the clinical, imaging and pathological findings of congenital intrapulmonary lymphangioma and hemangioma in 5 infants and young children. METHOD: Data of 3 cases with congenital intrapulmonary lymphangioma and 2 cases with haemangioma were analyzed. RESULT: All the 5 cases had cough, difficulty in breathing, cyanosis of lips, and shortness of breath. Imaging study indicated cystic and space occupying changes of partial lung. In the two cases of hemangioma, the blood vessels passing through the hemangioma were observed on CT films. Histochemical studies showed that the cystic pockets from removed tissues were different in size and there was a line of flat endothelial tissue around these pockets. Immunochemical studies indicated D2-40 positive, factor VIII weak positive for lymphangioma cases; while in hemangioma cases, factor VIII was positive, D2-40 was negative or weakly positive, and both of cytokeratin was negative. CONCLUSION: It is very important to consider and identify congenital intrapulmonary lymphangioma or hemangioma when a patient has cystic pockets and space occupying change in their lung by imaging and pathological studies.

[Clinical characteristics of primary ciliary dyskinesia in children].

OBJECTIVE: Although primary ciliary dyskinesia (PCD) is a group of inherited diseases, accurate diagnosis and appropriate clinical care to prevent and treat the complications could maintain patients' quality of life and normal life span. The diagnosis of PCD may often be delayed because it is frequently misdiagnosed as bronchitis, sinusitis and otitis. This study aimed to analyze and summarize the clinical features of PCD and explore diagnostic and differential diagnostic procedures in children. METHODS: Patients were all chosen from the inpatient department of Beijing Children's Hospital, Capital Medical University between 1990 - 2006. The tunica mucosa bronchiorum and/or nasal mucous membrane were gained through bronchoscope in children suspected to have PCD. The ciliary ultrastructures were analyzed through the electron microscope. The clinical features and procedures of the diagnosis and differential diagnosis in children with PCD were analyzed. RESULTS: There were totally 26 children diagnosed as PCD with 10 (38.5%) Kartagener syndrome. All Kartagener syndrome children had mirror image dextrocardia with normal cardiac structure and situs inversus viscerum. The bronchoscopy performed in eight of 10 Kartagener syndrome children showed bronchus transposition. Twenty-six children came from twenty-five families. Although the siblings of four probands also had the symptoms of chronic cough with sputum, running nose and recurrent respiratory infections, only a boy and his sister were diagnosed as Kartagener syndrome simultaneously. Their parents and the other family members were healthy. Of the 26 patients, 11 were boys and 15 were girls. The median age at diagnosis was 8.7 years. The age of onset was between the second day after delivery and fifteen years old, median age was 3 years. The course of disease before diagnosis was eleven days to twelve years (median 3.5 years). All the children had the symptom of cough, 24 of which had productive cough. Seven cases were found to have clubbing fingers. Dynein arm defect was found in 10 children, 6 of them had total absence of dynein arms and 4 had decreased dynein arm numbers. Microtube derangements were found in 8 children. One Kartagener syndrome child had a normal cilia structure. Bronchiectasis, consolidation and increased lung markings were found in 8, 6 and 7 patients separately on the radiographic study. Twenty patients had sinusitis. Nine of sixteen children had decreased PEF, FEV1 and/or FEF 25 - 75 on the pulmonary function test. Fifteen culture samples obtained from 6 children's sputum and/or bronchoalveolar lavage fluid were positive for 8 strains of Pseudomonas aeruginosa, 5 strains of Streptococcus pneumoniae and 2 strains of Candida albicans. In 1 subject more than one organism were found in the same sample. Hearing lost and gastroesophageal reflux were detected in 3 of 4 and 3 of 5 examined children respectively. CONCLUSIONS: The onset of PCD can occur from neonate to adolescence and usually has a chronic course. The common symptom of pediatric PCD was productive cough and significant growth retardation. The most common ultrastructural abnormalities associated with PCD were the total absence of dynein arms, decreased dynein arm numbers and microtube derangement. Some patients have normal ciliary structures. Bronchiectasis, consolidation and sinusitis were usually seen on the radiography. Pseudomonas aeruginosa and Streptococcus pneumoniae were the two common bacterial organisms obtained from sputum and/or bronchoalveolar lavage fluid of PCD children. Some patients have mixed infections. PCD children have high percentages of hearing lost and gastroesophageal reflux.

[Clinicopathological study of 145 childhood rhabdomyosarcoma cases].

OBJECTIVE: To study the clinicopathological, immunohistochemical and electron microscopic characteristics of pediatric rhabdomyosarcomas (RMS). METHODS: One hundred and forty-five cases of pediatric rhabdomyosarcomas were studied by routine histological, immunohistochemical and electron microscopic studies. RESULTS: There were 97 male and 48 female patients with ages ranging from 4 months to 13 years and a mean of 4.2 years. The follow-up period of 100 patients was from 1 year to 20 years with a mean of 5 years after diagnosis. All cases were subtyped into the following histological categories: embryonal RMS, botryoid RMS, spindle cell RMS, alveolar RMS and solid RMS. Histopathological subtypes, tumor site and tumor stage correlated significantly with the patients' 5 years survival. The best prognosis was observed in spindle cell and botryoid RMS. Embryonal RMS carried an intermediate prognosis. Patients with alveolar RMS and solid RMS had the worst prognosis. Tumors involving bladder, head and neck carried a favorable clinical outcome. Patients with tumors involving trunk extremities retroperitoneum and pelvis did poorly. Immunohistochemically, all cases were positive for Vimentin. The positive staining rates for desmin, SMA and myoglobin were 78%, 75% and 37%, respectively. All tumors were negative for NSE, CD99 and LCA. Electron microscopy study showed features of myofilament and sarcomere in 10 of 15 cases. CONCLUSIONS: RMS is the most common soft tissue sarcoma of childhood. Immunohistochemistry and electron microscopy are helpful in diagnosis and classification of RMS.