Mucoepidermoid carcinoma of the bronchus presenting with a negative chest X-ray and normal pulmonary function in two teenagers: two case reports and review of the literature

The Different Clinical Aspects of Pediatric Primary Airway Tumors in the Larynx, Trachea, and Bronchi

Primary airway tumors are rare in children and no literature reviewed their characteristics each location. We evaluate the clinical characteristics and outcomes of Korean children with primary airway tumors, from the larynx to bronchi. A retrospective chart review of children with primary tumors of the larynx, trachea, and bronchi at Asan Medical Center from January 2000 to July 2016 was conducted. Nineteen children were diagnosed with primary airway tumors of the larynx (47.4%), trachea (10.5%), and bronchi (42.1%). Median follow-up duration was 2.8 years and there were recurrences in 21.1%. Laryngeal tumors were associated with a younger median age at onset (2 months) and diagnosis (4 months), and most were relatively small (median size = 5.3 mm) and symptomatic. Tracheal and bronchial tumors were found in older children (age at onset and diagnosis > 11 years) and large (> 15.0 mm). Most (75%) patients with bronchial tumors were asymptomatic and all the patients with tracheal tumors were symptomatic. This study suggests that we should consider different the locations in primary airway tumor based on the age at onset and diagnosis, initial symptoms or signs, and size of tumor.

Clinicopathological and multisection CT features of primary pulmonary mucoepidermoid carcinoma

AIM

To delineate the multisection computed tomography (MSCT) features and the clinical characteristics of primary pulmonary mucoepidermoid carcinoma (PMEC). Prognostic factors were also analysed.

MATERIALS AND METHODS

A retrospective study was undertaken to investigate the medical records and MSCT performance of histopathologically confirmed PMECs from 2007 to 2015.

RESULTS

A total of 83.3% of patients with high-grade PMECs were aged >40 years, whereas there were 1.5-times more women than men with low-grade PMECs. Cough (n=29) and haemoptysis (n=12) were the most common symptoms. Upon MSCT, 30 cases showed a round or lobulate mass, and few demonstrated bronchial-wall thickening or cavities. Distal obstruction (n=14) and "air crescent sign" (n=5) could be detected. Tumours showed mild (n=19), moderate (n=5), and marked enhancement (n=5). Moreover, 18 cases showed foci of low density in lesions. Mean survival for patients with low-grade PMECs was 59.2 months, whereas that for high-grade PMECs was 20.4 months; 3-year survival rates were 55% and 14%, respectively. Tumour staging was a significant independent predictor of survival according to the Cox proportional hazards model.

CONCLUSION

High-grade PMECs occurred more frequently in patients aged >40 years and were more predominant in men. Young females were predisposed to having low-grade PMECs. MSCT revealed an oval or lobulate mass with mild enhancement, as manifested by calcification and visible mucus lakes, which may be suggestive of PMECs. Furthermore, a central nodule or mass may suggest low-grade PMECs; high-grade PMECs tend to be peripheral and associated with lymph-node metastasis. Pathological grade, lymph node metastasis, and TNM stage correlate with the survival of patients with PMEC.

Childhood and adolescent tracheobronchial mucoepidermoid carcinoma (MEC): a case-series and review of the literature

Tracheobronchial mucoepidermoid carcinomas (MEC) are rare in the pediatric population with literature limited primarily to case reports. Here we present our institutional experience treating MEC in three patients and review the literature of 142 pediatric cases previously published from 1968 to 2013. Although rare, tracheobronchial MEC should be included in the differential diagnosis in a child with recurrent respiratory symptoms. Conservative surgical management is often sufficient to achieve complete resection and good outcomes.

Endobronchial tumor in children: Unusual finding in recurrent pneumonia, report of three cases

We are reporting 3 cases of pediatric endobronchial tumors presented with recurrent pneumonia. The median age of patients, at time of presentation, was 10.6 years. All patients presented with recurrent pneumonia with a mean time to occurrence, after onset of symptoms, of 14 mo. Bronchoscopy was early performed as part of diagnostic work-up and it revealed an endobronchial mass in every case. Complete surgical resection was performed in all cases, with lung preservation in two of them. Neither post-operative chemotherapy nor radiotherapy was required. The mean duration of follow-up was 7 years and all patients are still alive and disease-free. Recurrent pneumonia, in pediatrics, should raise the suspicion of an obstructing lesion, congenital malformation or systemic disease. A systematic approach is useful for organize the clinicians initial workup. Prompt diagnosis allows parenchymal-sparing surgery, which offers the best chance of cure and reduces clinical and functional complications in these patients.

Childhood bronchial mucoepidermoid tumors: A case report and literature review

Primary pulmonary neoplasms rarely occur in children, but the majority of those that do are malignant. Mucoepidermoid carcinoma (MEC) represents ~10% of all primary pulmonary malignant tumors. However, MEC is not usually considered in the clinical differential diagnosis in pediatric practice. The present study presents the case of a seven-year-old female with a one-year history of recurrent hemoptysis. Computerized tomography (CT) scans revealed a tumor originating in the right lower lobe bronchus. The patient did not receive any radiation and chemotherapy following a lobectomy on the right lower lung. The tumor was histopathologically determined to be an MEC of the tracheobronchial tree. Subsequent to a six-year follow-up, the MEC was undetectable in this patient, according to the clinical and radiological evidence. The literature with regard to pediatric MEC is also reviewed in this study.

Mucoepidermoid carcinoma of bronchus in a pediatric patient: (18)F-FDG PET findings

In children, primary neoplasms of the tracheobronchial tree and lungs are rare; most are malignant. Of the primary malignant pulmonary neoplasms arising in childhood, mucoepidermoid carcinoma accounts for approximately 10%. Due to its well-confined local growth within the airway, mucoepidermoid carcinoma commonly produces respiratory symptoms from progressive tracheal or bronchial obstruction. Mucoepidermoid tumor has minimal metastatic potential in children, and local resection alone is the current treatment of choice. Early detection, diagnosis, and surgical resection of mucoepidermoid tumor are especially important in pediatric patients since the bulk of the remaining pulmonary parenchyma can be preserved, thereby decreasing the thoracic deformity and pulmonary functional morbidity. Radiographic and CT imaging findings of bronchial mucoepidermoid carcinoma in children have been described in several case reports. However, to the best of our knowledge, imaging findings of 2-((18)F)-fluoro-2-deoxy-D: -glucose positron emission tomography ((18)F-FDG PET) of mucoepidermoid carcinoma of the bronchus in pediatric patients have not been well established. We report a mucoepidermoid carcinoma arising from the right upper lobe bronchus in a 15-year-old girl with an emphasis on the (18)F-FDG PET findings.

Mucoepidermal carcinoma of the lung detected by positron emission tomography in a 5-year-old girl

The authors describe a rare case of mucoepidermal carcinoma of the lung incidentally identified in preoperative assessments for inguinal hernia repair in a 5-year-old girl. This patient was referred for right external inguinal hernia, and a 3.0-cm round-shaped lesion was found in the right lower lung field of a chest x-ray film. She had no respiratory tract complaints, but her serum carcinoembryonic antigen concentration was markedly elevated (21.2 ng/mL). Chest and abdominal computed tomography/magnetic resonance images could not determine the nature of the lesion, but 2-[18 F]fluoro-2-deoxy- d -glucose positron emission tomography (FDG-PET) indicated a malignant tumor pattern. The patient underwent a computed tomography-guided needle biopsy of the lesion (S8), which was soon followed by a right lower pulmonary lobectomy. Histopathology of the resected specimen showed mucoepidermal carcinoma with no regional lymph node metastasis. In childhood asymptomatic pulmonary lesions, it is often difficult to rule out the possibility of malignancy. In the present case, FDG-PET scanning appropriately indicated the therapeutic priority of pediatric thoracic surgery.

Mucoepidermoid carcinoma as an unusual cause for recurrent respiratory infections in a child

Recurrent respiratory infections in a 9-year-old girl prompted a chest radiograph and a CT scan, which showed a right middle lobe consolidation. Bronchoscopy revealed a tumor that totally obstructed the middle lobe. Open lung biopsy revealed a low-grade mucoepidermoid carcinoma. Middle and lower right lung lobectomy was performed, followed by an uneventful recovery. Cytogenetic investigation of tumor cells exhibited the translocation t(11;19). This case shows that further diagnostic modalities such as CT scanning should be performed early in children with recurrent lower respiratory tract infections who have suspicious radiographic findings such as persistent atelectasis or recurrent unifocal infiltration. Bronchial mucoepidermoid carcinoma is infrequent, and molecular investigations might shed additional light on the prognosis.