A team of surgeons

                                                                                                                                                                                                                                               

Bronchial mucoepidermoid carcinoma

 

1- Definition

mucoepidermoid carcinoma  of the broncus is a rare primary airway arising from the excretory ducts of the submucosal bronchial gland (JOURNAL OF BRONCHOLOGY& INTERVANTIONAL PNEUMOLOGY JAN 2009 volume 16 chua,Ai-Ping and colleagues

(MECs) are a distinct and rare form of malignant tumors that originate in the submucosal bronchial glands.   (journal of cancer research and therapeutics 2014 volume 10 )

( international journal of surgery) MEC is a common neoplasia of the salivary glands,inicially described by Stewart et Al. in 1945, reported in bronchi by Smetana  et Al.in 1952

Epidemiology

It forms with the carcinoid tumors the most frequent endobronchial lesions. The average of age of occurrence is before the twenties according to some sturdies, at the twenties for others and at the fifties for others. and occur in equal incidence between both sexes

 

 

Etiology

The increased frequency of this tumor in the pediatric population suggests a genetic abnormality. Recent genetic studies have demonstrated reciprocal chromosomal translocations including t(1;11)(p22;q13), t(11;19)(q14-21;p12), and t(11; 19)(q21;p13). Chromosome 11 in the first translocation appears to have been altered resulting in up-regulation of the cyclin D1 gene and overexpression of cyclin D1. ( LIU X et Al. Arch pathol lab med 2007)

there is no predilection predilection for 1 lung over the other, they may have a predilection for the proximal portion of the lobar bronchus. (Journal of bronchology & interventional pulmonology)

no correlation with smoking.

 

 

Signs and symptoms

chronic respiratory complaints, including cough,hemoptisysis exercise intolerance, and persistent wheezing, the symptoms are persistent like asthma.In adults there is fever, non productive cough and dyspnea. A cervical adenopathy, 

 

physiopathology

Microscopically, the tumors are located in the submucosa of the large bronchi. The tumors are usually well differentiated and contain a combination of mucus-secreting, squamous, and intermediate cells.( LIU X et Al. Arch pathol lab med 2007). They consist of mucus-secreting cells, squamous cells, and intermediate cells. The predominance of cell types acts as one of the grading criteria. Almost all mucoepidermoid carcinomas are low-grade tumors and require surgery but no adjuvant therapy if resected.

the gros aspet  of MECs shows an oval or round shape hard-elastic consistancy,smooth  margins and yellowish-tan colour

 

 

diagnostic

Chest X-ray and CT scan are the main imaging tools for the evaluation of MECs. 

Chest X-ray : area of inflammattryory consolidation

CT Scan it shows a intraluminal lesion

The flexible bronchoscopy represents the main diagnostic tools for MECs, allowing direct view and biopsy

Immunohistochemistry

 

traitment

Some surgeons have reported the practice of a lobectomy, and a mediastinal lymphadenectomy through anterolateral thorachotomy. No further therapies were employed, given the stage of the disease. 

the treatment is usually surgical by traditional or sleeve lobectomy,performed with an open or video-assisted technique, but patients in the  high-grade group have a poor prognosis because of metastasis.

 

 

 

Date de dernière mise à jour : 20/04/2019