%0 Journal Article %T Unusual Synchronous Lung Tumors: Mucoepidermoid Carcinoma and Mucinous Adenocarcinoma %A Ana M. Ponea %A Creticus P. Marak %A Ying Sun %A Achuta Kumar Guddati %A Amit S. Tibb %J Case Reports in Oncological Medicine %D 2014 %I Hindawi Publishing Corporation %R 10.1155/2014/183617 %X Primary mucoepidermoid tumors of the lung are rare entities. Synchronous primary malignancies of the lung involving mucoepidermoid carcinoma and mucinous adenocarcinoma are even rarer and constitute a unique set of patient population. The presentation, diagnosis and treatment strategies for this patient population are not well described. In most cases, the diagnosis of synchronous primary lung malignancy is made after pathological examination of the resected lung specimen. Molecular and genetic analysis is now being used to supplement the diagnosis of synchronous primary lung malignancies. In this work, we briefly discuss the current state of knowledge of this unique combination of primary lung malignancies and describe the clinical presentation and management of a patient with a rare combination of synchronous primary lung malignancies. 1. Introduction Synchronous tumors are defined as two or more primary neoplasms which are detected simultaneously. They differ from metachronous tumors which are detected after an intervening interval in their epidemiology, prognosis, and management [1]. Precancerous lesions have been found at a higher frequency in patients with multiple primary lung cancers, but the genetic basis of such malignancies is yet to be elucidated [2, 3]. It is possible that the development of synchronous tumors is related more to environmental exposure than to genetic predisposition as seen by the higher incidence of synchronous tumors in workers exposed to chromate [4]. However, there is some evidence to show that genetic predisposition may play a role as multiple primary lung cancers have been observed to be inherited in some families [5]. Mutations in the p53 protein and allelic loss of heterozygosity have been shown to be associated with synchronous lung primary malignancies [6, 7]. Similar trend with malignancies involving other organ systems has been noted in patients with significant smoking history providing credence to the hypothesis of field cancerization [8]. The diagnosis of true synchronous primary lung tumors with different histologies has been difficult due to two reasons: some patients with multiple primary lung tumors with different histologies have been found to have identical genetic changes suggesting a monoclonal origin and some with patients with identical histologies have been found to have different clonal origins [9¨C11]. This is complicated by the fact that regional heterogeneity in tumor grade can be observed in individual neoplasms and metastases may have different tumor grades when compared to their primary %U http://www.hindawi.com/journals/crionm/2014/183617/