A Comparative Study of Primary Adenoid Cystic and Mucoepidermoid Carcinoma of Lung

Abstract

BackgroundPulmonary mucoepidermoid carcinoma (PMEC) and pulmonary adenoid cystic carcinoma (PACC) are the two major types of primary salivary gland-type (PSGT) lung cancers. The demographic profile, clinicopathological features, and predictors of survival as an overall group have not been described for PSGT cancers of lung.MethodsIn this study, we analyzed demographic, clinical, and survival data from 1,032 patients (546 PMEC and 486 PACC) who were diagnosed of PSGT lung cancer in the Surveillance, Epidemiology and End Results database from 1973 to 2014.ResultsThe PSGT constituted 0.09% of all lung cancers with age-adjusted incidence rate of 0.07 per 100,000 person-years and change of −32% from 1973 to 2014. The incidence of PMEC was slightly higher than PACC but there were no differences in the age and sex distribution. PACCs (55%) were significantly higher at trachea and main bronchus while PMECs were more common at peripheral lungs (85%). Most of the tumors were diagnosed at an early stage and were low grade irrespective of histology. As compared to PMEC, significantly higher number of patients with PACC underwent radical surgery and received adjuvant radiation. The 1- and 5-year cause-specific survival was 76.6 and 62.8%, respectively. On multivariate analysis, the survival was affected by age at diagnosis, tumor stage, histological grade, period of diagnosis, and surgical resection. The histology showed strong interaction with time and hazard ratio of patients with PACC was significantly worse than patients with PMEC only after 5 years.ConclusionThe incidence of pulmonary PSGT cancer is 7 cases per 10 million population in the United States and is decreasing. There was no difference between demographic profile of patients with PMEC and PACC but pathological features were diverse. The difference in the survival of patients with the two histological types surfaced only after 5 years when survival of patients with PMEC was better than PACC.

Clinical outcomes and the role of bronchoscopic intervention in patients with primary pulmonary salivary gland-type tumors

“…Most studies regarding PSGT are small studies or case reports due to its rarity. Although some studies have reported a relatively large number of PSGT cases, these reports have not discussed the role of bronchoscopic intervention in detail [1,5,19]. In the present study, we reported the clinical outcomes of PSGT and the prognostic factors that affect survival and disease Fig.…”

“…However, there were several different results depending on the histologic type of PSGT as a prognostic factor of OS. Some studies have reported that ACC has a lower survival rate than MEC, because ACC patients were older and had larger tumor size and more lymph nodes involved than MEC patients [1,6,19]. In particular, two prior studies suggested that the mortality pattern differs between ACC and MEC.…”

Pulmonary mucoepidermoid carcinoma: Clinicopathological characteristics of 20 cases and a literature review

“…Based on the WHO Classification of lung tumors (2015), primary salivary gland-type tumors(pSGTs) can be divided into the following four types: mucoepidermoid carcinoma (MEC), adenoid cystic carcinoma (ACC), epithelial-myoepithelial carcinoma (EMC), and pleomorphic adenocarcinoma (PA) 6 [8]. Pulmonary mucoepidermoid carci noma is the most common type of pSGTs, followed by PACC [9].…”

Pulmonary mucoepidermoid carcinoma: Clinicopathological characteristics of 20 cases and a literature review

“…Pulmonary mucoepidermoid carci noma is the most common type of salivary gland tumor [8]. Previous studies indicated that PMEC had a broad spectrum in age and often occurred in 40s [5,9].…”