Mucoepidermoid carcinoma of lung: potential target of EGFR-directed treatment

Efficacy and Safety of First-Line Platinum-Based Doublet Chemotherapy in Advanced Primary Pulmonary Salivary Gland Tumors (PSGTs)

Primary pulmonary salivary gland tumors (PSGT) constitute a rare subtype of non-small cell lung cancer (NSCLC). Currently, no established treatment guidelines exist for advanced PSGT. The efficacy of platinum-based chemotherapy for PSGT within the context of NSCLC remains uncertain. Therefore, we retrospectively collected 37 PSGT patients who underwent first-line platinum-based chemotherapy from 2010 to 2023. Survival analysis, employing the Kaplan-Meier method, and group comparisons via the log rank test were conducted. Our results show that first-line platinum-based chemotherapy demonstrates favorable efficacy and manageable safety in advanced PSGT, with the combination of Paclitaxel + Platinum emerging as a preferred option.

Rare but clinically important salivary gland-type tumor of the lung: A review

Salivary gland-type tumor (SGT) of the lung, which arises from the bronchial glands of the tracheobronchial tree, was first recognized in the 1950s. SGT represents less than 1% of all lung tumors and is generally reported to have a good prognosis. Mucoepidermoid carcinoma (MEC) and adenoid cystic carcinoma (ACC) are the two most common subtypes, comprising more than 90% of all SGTs. The reported 5-year survival rate of patients with SGT is 63.4%. Because this type of tumor develops in major bronchi, patients with SGT commonly present with symptoms of bronchial obstruction, including dyspnea, shortness of breath, wheezing, and coughing; thus, the tumor is usually identified at an early stage. Most patients are treated by lobectomy and pneumonectomy, but bronchoplasty or tracheoplasty is often needed to preserve respiratory function. Lymphadenectomy in the surgical resection of SGT is recommended, given that clinical benefit from lymphadenectomy has been reported in patients with MEC. For advanced tumors, appropriate therapy should be considered according to the subtype because of the varying clinicopathologic features. MEC, but not ACC, is less likely to be treated with radiation therapy because of its low response rate. Although previous researchers have learned much from studying SGT over the years, the diagnosis and treatment of SGT remains a complex and challenging problem for thoracic surgeons. In this article, we review the diagnosis, prognosis, and treatment (surgery, chemotherapy, and radiotherapy) of SGT, mainly focusing on MEC and ACC. We also summarize reports of adjuvant and definitive radiation therapy for ACC in the literature.

Primary Mucoepidermoid Carcinoma of the Lung Coexisting With Pulmonary Tuberculosis: A Rare Case Report

Mucoepidermoid carcinoma (MEC) is a well-established neoplasm of the salivary glands. However, the MEC of the lung is an exceedingly rare neoplasm that falls under the category of salivary gland-type tumors of the lung. Pulmonary MEC is recognized for its indolent progression. Pulmonary tuberculosis (TB) is a prevalent infectious disease in India and ranks among the leading causes of death from infectious diseases. Nevertheless, the co-occurrence of pulmonary MEC with pulmonary TB is a rare phenomenon that has not been documented in the literature. In this report, we describe a 54-year-old male patient who presented with symptoms of dysphagia, weight loss, and fever. Histopathological examination diagnosed him with pulmonary MEC, and concurrent cytology and Gene-Xpert tests confirmed tuberculosis. This case represents the first documented instance of this particular co-occurrence. It underscores the limitations of radiology in diagnosing such a rare neoplasm, especially when there is an absence of lung parenchyma infiltration and a mass lesion. Additionally, this case supports the possibility of an interdependent relationship between malignancies and tuberculosis.

A case of lung carcinoma with a unique biphasic feature: Implications for histogenesis of "fake mucoepidermoid carcinoma" developing in the peripheral lung

We present a case of lung carcinoma with a unique biphasic feature. The patient was a 67-year-old male smoker with idiopathic pulmonary fibrosis (IPF). A subpleural tumor in the left lower lobe, embedded in fibrotic tissue, was resected. Histologically, the tumor consisted of major and minor components of mucoepidermoid carcinoma (MEC) and surrounding conventional lepidic adenocarcinoma, respectively. Both components had the same TP53 somatic mutation (p.V157F) but not Mastermind-like 2 (MAML2) gene rearrangement. The two components may have developed from an identical origin. The tumor could be trans-differentiating from lepidic adenocarcinoma to MEC, possibly promoted by IPF-induced tissue damage. The final diagnosis was "adenosquamous carcinoma with mucoepidermoid-like features (that may originate from lepidic adenocarcinoma)." This case has implications for the potential histogenesis of peripheral lung MEC. Over time, the MEC would expand and outgrow the lepidic adenocarcinoma, making it impossible to distinguish between fake and true MEC. The present case suggests that peripheral MEC could differ from proximal MEC in its histogenesis and molecular genetics. Thus, careful examination is necessary to diagnose peripheral lung MEC, particularly in patients with interstitial lung diseases.

Targeted therapy for rare lung cancers: Status, challenges, and prospects

Lung cancer causes the most cancer-related deaths worldwide. In recent years, molecular and immunohistochemical techniques have rapidly developed, further inaugurating an era of personalized medicine for lung cancer. The rare subset of lung cancers accounts for approximately 10%, each displaying distinct clinical characteristics. Treatments for rare lung cancers are mainly based on evidence from common counterparts, which may lead to unsolid clinical benefits considering intertumoral heterogeneity. The increasing knowledge of molecular profiling of rare lung cancers has made targeting genetic alterations and immune checkpoints a powerful strategy. Additionally, cellular therapy has emerged as a promising way to target tumor cells. In this review, we first discuss the current status of targeted therapy and preclinical models for rare lung cancers, as well as provide mutational profiles by integrating the results of existing cohorts. Finally, we point out the challenges and future directions for developing targeted agents for rare lung cancer.

Molecular Mechanisms of Carcinogenesis in Pediatric Airways Tumors

Primary tumors of the airways in the pediatric population are very rare entities. For this reason, little is known about the pathogenesis of these neoplasms. Understanding the biology has different practical implications: for example, it could help in the differential diagnosis, have a prognostic significance, or may lead to the development of a targeted therapy. The aim of this article is to present the current knowledge about pediatric airways tumors, focusing on the molecular mechanisms that cause the onset and progression of these neoplasms. After a brief introduction of epidemiology and clinical presentation, the tumorigenesis of the most frequent pediatric airways tumors will be described: Juvenile-onset recurrent respiratory papillomatosis (JORRP), Subglottic Hemangiona (SH), Rhabdomyosarcoma (RMS), and Mucoepidermoid carcinoma (MEC).

Mucoepidermoid carcinoma of the bronchus in two children: Case reports

Childhood mucoepidermoid carcinomas (MEC) of the bronchus are rare. They present with non-specific symptoms and signs making diagnosis delayed. We present two children with bronchial MEC managed in a tertiary children's hospital in Cape Town, South Africa. The first was a 11-year male with recurrent haemoptysis and the second child was a 6-year female with recurrent unifocal pneumonia. Chest CT scan and bronchoscopy with biopsy confirmed the diagnosis. Both patients underwent treatment, including surgery and are doing well. It is important to exclude endobronchial lesions when children present with recurrent respiratory symptoms, since early diagnosis will enable lung-sparing treatment.

Pulmonary Salivary Gland Tumor, Mucoepidermoid Carcinoma: A Literature Review

Pulmonary mucoepidermoid carcinoma (PMEC) is the most common malignant salivary gland tumor in the lungs and accounts for 0.1-0.2% of all lung malignancies in adults. It has no specific epidemiological or clinical characteristics. Correct diagnosis requires the combined examinations of images, laboratories, pathology, and immunohistochemistry (IHC) as well as molecular characteristics. PMEC tumors are characterized by squamous, intermediate, and mucus-secreting cells. Currently, histological appearance, mitotic frequency, cellular atypia, and necrocytosis allow the classification of PMEC into low grade or high grade. Molecular changes are crucial to pathological diagnosis. The driver of PMEC seems to be the fusion protein MECT1-MAML2 that is generated from a genetic mutation in t (11; 19) (q21; p13), while other gene mutations are also reported. However, no treatment of PMEC exists so far; surgical excision is still the primary treatment, while the efficacies of chemotherapy or radiotherapy are undefined. Tyrosine kinase inhibitor (TKI) therapy and immunotherapy showed to have significant therapeutic effects but require more investigation and better understanding. This review focuses on the clinical characteristics, imaging and pathologic features, immunohistochemical examination, mutation analysis, differential diagnosis, prognosis, and treatment of PMEC.

Mucoepidermoid carcinoma of the trachea in a 9-year-old male child: case report and review of literature

Mucoepidermoid carcinoma (MEC) is the most common malignancy of minor salivary glands in adults. Pulmonary MEC is extremely uncommon, comprising only 0.1–0.2% of the primary lung malignancies and <1% of primary bronchial tumors. It is even rarer in children, and literature is limited to a few case reports only. Here we present a case report of a 9-year-old boy diagnosed with primary MEC of the trachea along with a review of the literature. A 9-year-old male child presented with complaint of dry cough for two years which was later associated with shortness of breath after one year. Bronchoscopic examination revealed a growth arising from right lateral wall of carina occluding 50% of the lumen and detailed histopathological examination revealed it to be a MEC of the trachea. The patient underwent local excision of the tumor with primary anastomosis. Because of positive margin, adjuvant radiotherapy of 60 Gy in 30 fractions was given to the tumor bed. The patient tolerated the treatment well and is disease free at 6 months follow-up. Experience with MEC of the trachea in children is limited, and optimal treatment protocols have not been defined, with current treatment mainly extrapolated from MEC of the salivary glands.

PCP4/PEP19 and HER2 Are Novel Prognostic Markers in Mucoepidermoid Carcinoma of the Salivary Gland

Simple Summary

Mucoepidermoid carcinoma (MEC) is the most common malignancy of all salivary neoplasms, and no effective treatment strategy for MEC has been established other than resection. In this study, we showed that Purkinje cell protein (PCP) 4/peptide (PEP) 19 and human epidermal growth factor receptor 2 (HER2) are predicted to play important roles in the pathogenesis and progression of MEC. The detection of PCP4/PEP19 and HER2 may be useful for providing more effective treatments against MEC.

Abstract

Mucoepidermoid carcinoma (MEC) is one of the most common malignant salivary gland carcinomas, but no effective treatment strategy has been established other than surgical resection. Purkinje cell protein (PCP) 4/peptide (PEP) 19 is a calmodulin-binding antiapoptotic peptide that is expressed and inhibits apoptosis in human breast cancer cells. Human epidermal growth factor receptor 2 (HER2) is an epidermal growth factor that has been implicated in the pathogenesis of many carcinomas, particularly breast and gastric carcinomas. In the present study, we performed immunohistochemical analyses of samples from 73 patients who underwent surgical resection for MEC of the salivary gland using antibodies against PCP4/PEP19 and HER2. PCP4/PEP19 expression was related to better prognosis, while HER2 expression was associated with worse prognosis. Patients that were PCP4/PEP19-positive and HER2-negative showed similar outcomes to PCP4/PEP19 and HER2 alone. Therefore, PCP4/PEP19 and HER2 are predicted to play important roles in the pathogenesis and progression of MEC.

Salivary Gland Cancers

Salivary gland carcinomas are a rare and heterogenous group of cancers with varying underlying biology and clinical behavior. A quickly evolving body of data has advanced the understanding of these tumors, leading to effective therapeutics for several histologic subtypes. Biologically rational clinical trials have developed from an understanding of MYB and NOTCH signaling in adenoid cystic carcinoma. The recognition of androgen receptor signaling and HER2-targeted therapy has offered therapeutic options in non-ACC salivary cancers. The use of TRK inhibitors in salivary secretory carcinoma has led to exceptional responses. Immunotherapy is an exciting new therapeutic avenue that requires further exploration.

Rapid metastasis of stage IA primary pulmonary high-grade mucoepidermoid carcinoma with a cystic airspace: a case report and reflection

Primary pulmonary high-grade mucoepidermoid carcinoma (MEC) with a cystic airspace is uncommon, and early metastasis is extremely rare. In such cases, however, it is clinically important for clinicians to consider whether the tumor has spread to the lymph nodes through the cystic airspace. A 77-year-old man presented to our hospital with cough and hemoptysis. Chest computed tomography showed a 25-mm-diameter mass with a cystic airspace located in the upper lobe of the left lung. The possibility of malignancy was considered. Without a definitive preoperative diagnosis, left upper lobectomy and mediastinal lymphadenectomy were performed. Histopathological examination revealed the typical histological characteristics of high-grade MEC (stage IA) and no lymph node metastasis. However, lymph node metastasis was found 6 months after surgical resection, and radiochemotherapy was performed. The patient developed widespread metastatic disease 4 months following completion of radiochemotherapy and died 2 months later. Primary pulmonary MEC with a cystic airspace is a rare malignant disease with uncommon imaging findings. Complete surgical resection is the main treatment method for high-grade MEC. In this case, we hypothesize that early metastasis was caused by seeding of tumor cells through the cystic airspace.

Gefitinib Represses JAK-STAT Signaling Activated by CRTC1-MAML2 Fusion in Mucoepidermoid Carcinoma Cells

BACKGROUND

Gefitinib is well-known as a tyrosine kinase inhibitor targeting non-smalllung- cancer (NSCLC) containing EGFR mutations. However, its effectiveness in treating mucoepidermoid carcinoma (MEC) without such EGFR mutations suggests additional targets.

OBJECTIVE

The CRTC1-MAML2 (C1-M2) fusion typical for MEC has been proposed to be a gefitinib target.

METHODS

To test this hypothesis, we developed a set of siRNAs to down-regulate C1-M2 expression. RNA-seq and Western blot techniques were applied to analyze the effects of gefitinib and siC1-M2 on the transcriptome of and the phosphorylation of tyrosine kinases in a MEC cell line H292.

RESULTS

Deep-sequencing transcriptome analysis revealed that gefitinib extensively inhibited transcription of genes in JAK-STAT and MAPK/ERK pathways. Both siC1-M2 and gefitinib inhibited the phosphorylation of multiple signaling kinases in these signaling pathways, indicating that gefitinib inhibited JAK-STAT and MAPK/ERK pathways activated by C1-M2 fusion. Moreover, gefitinib inhibition of EGFR and MAPK/ERK was more effective than that of AKT, JAK2 and STATs, and their dependence on C1-M2 could be uncoupled. Taken together, our results suggest that gefitinib simultaneously represses phosphorylation of multiple key signaling proteins which are activated in MEC, in part by C1-M2 fusion. Gefitinib-repressed kinase phosphorylation explains the transcriptional repression of genes in JAK-STAT and MAPK/ERK pathways.

CONCLUSION

These findings provide new insights into the efficacy of gefitinib in treating mucoepidermoid carcinoma, and suggest that a combination of gefitinib and other inhibitors specifically against C1-M2 fusion could be more effective.

ROS-mediated NLRP3 inflammasome activation participates in the response against Neospora caninum infection

Background

Neospora caninum is an obligate intracellular protozoan that causes neosporosis, N. caninum infection is a major cause of abortion in cattle worldwide. Currently, specific treatment for neosporosis is not available. The NOD-like receptor family pyrin domain containing 3 (NLRP3) inflammasome is a cytoplasmic protein complex that plays an important role in host defense against N. caninum infection, but the underlying mechanisms are poorly understood.

Methods

The reactive oxygen species (ROS) inhibitor and the ROS inducer, wild-type (WT) and NLRP3-deficient peritoneal macrophages or mice were used to investigate the role of ROS in NLRP3 inflammasome activation and controlling parasite burdens. ROS production, cell death and cell viability, production of inflammasome-mediated IL-1β or IL-18, cleavage of caspase-1 and NLRP3 expression, as well as parasite burdens were detected.

Results

In vitro, N. caninum induced ROS generation in a dose-dependent manner in peritoneal macrophages. The pretreatment of ROS inhibitor N-acetyl-l-cysteine (NAC) significantly attenuated N. caninum-induced ROS production, LDH release, IL-1β secretion and NLRP3 expression, whereas N. caninum proliferation was notably increased. In contrary, the ROS inducer pyrogallol (PG) significantly enhanced ROS production and NLRP3 inflammasome activity and decreased the parasite burden in N. caninum-infected peritoneal macrophages. NADPH-dependent ROS-mediated NLRP3 inflammasome activation induced by N. caninum can also be confirmed by using the NADPH oxidase inhibitor diphenyleneiodonium chloride (DPI). However, the NAC or DPI pre-treatment or PG treatment did not significantly alter N. caninum-induced inflammasome activities and parasite proliferation in Nlrp3^−/− peritoneal macrophages. In vivo, IL-18 releases in serum and parasite burdens in peritoneal exudate cells were significantly increased in PG-treated WT mice after infection with N. caninum; however, IL-18 productions and parasite burdens were not changed in PG-treated Nlrp3^−/− mice. Furthermore, PG treatment in WT mice infected with N. caninum significantly decreased the mortality, weight loss and parasite burdens in tissues and histopathological lesions.

Conclusions

Neospora caninum-induced NADPH-dependent ROS generation plays an important role in NLRP3 inflammasome activation and controlling parasites. The ROS inducer PG can control N. caninum infection mainly by promoting NLRP3 inflammasome activation. ROS-mediated NLRP3 inflammasome axis can be a potential therapeutic target for neosporosis.

Anaplastic Lymphoma Kinase-Positive Lung Cancer with Mucoepidermoid Carcinoma Differentiation: A Case Report

Mucoepidermoid carcinoma (MEC) of the lung is an extremely rare tumor, and a standard chemotherapy has not been established. Furthermore, little work has been conducted on the genetic characteristics of MEC. We herein report the case of a 42-year-old nonsmoking male patient who was referred to our hospital due to cough. Chest computed tomography demonstrated infiltration and atelectasis in the right lower lobe. He was eventually diagnosed with non-small cell lung cancer (NSCLC) with MEC differentiation corresponding to clinical stage IVA (cT4N2M1a[PLE]). Genetic testing for EGFR mutations was negative, but positive for anaplastic lymphoma kinase (ALK) fusion gene. After 2 weeks of first-line treatment with alectinib, the tumor decreased in size and his symptoms improved. Advanced MEC is a rare tumor, and reports on the treatment of ALK-positive NSCLC with MEC differentiation are rare.

Clinicopathological significance of EGFR pathway gene mutations and CRTC1/3-MAML2 fusions in salivary gland mucoepidermoid carcinoma

AIMS

Mucoepidermoid carcinoma (MEC) is one of the most common salivary gland carcinomas. Epidermal growth factor receptor (EGFR) signalling pathway gene mutations are important in predicting a patient's prognosis, selecting molecularly targeted drugs and estimating the efficacy of a molecular therapy. However, their significance in MEC have been poorly clarified. CRTC1/3-MAML2 fusions are specific to MEC and may be associated with favourable characteristics in these patients.

METHODS AND RESULTS

We looked for CRTC1/3-MAML2 fusions and gene alterations in the EGFR, RAS family (KRAS, HRAS and NRAS), PIK3CA, BRAF and AKT1 in 101 MEC cases. We also examined mutations in TP53. CRTC1/3-MAML2 fusions were found in 62.4% of the cases. KRAS, HRAS and PIK3CA mutations were detected in 6.9%, 2.0% and 6.9%, respectively, but other EGFR pathway genes were not mutated. In total, gene mutations (RAS/PIK3CA) in the EGFR pathway were detected in 14.9% of the cases. TP53 mutations were found in 20.8%. CRTC1/3-MAML2 fusions were associated with a better prognosis and RAS/PIK3CA mutations a worse prognosis of the patients, respectively, and both were selected as independent prognostic factors for the overall survival of the patients. TP53 mutations had no prognostic impact. CRTC1/3-MAML2 fusion-positive rates were inversely associated with the patients' age and the fusions were found in 82% of patients aged < 30 years.

CONCLUSIONS

RAS/PIK3CA mutations were frequently detected, and may be a biomarker for a poorer prognosis in MEC patients. CTRC1/3-MAML2 fusions were positive in most of the young MEC patients.

Advances and challenges in precision medicine in salivary gland cancer

Salivary gland cancer (SGC) is a rare malignancy consisting of 22 subtypes with different genetic, histological and clinical characteristics. This rarity and heterogeneity makes systemic treatment of recurrent or metastatic (R/M) disease challenging. Use of chemotherapy is scarcely studied and chemotherapy at best has moderate effects. New therapeutic strategies are therefore warranted, but advances made in SGC are lagging behind on advances made in more common cancers. By unraveling tumor characteristics of SGC, such as genetic alterations and protein expression profiles, therapeutic strategies tailored to the patient's tumor can be rationalized. This genomic profiling and mapping of immunohistochemical expression profiles is essential in the search for a suitable treatment approach. Thereby, it alleviates the paucity in systemic treatment options and can significantly alter the prognosis of patients with R/M SGC. This review aims to give a comprehensive overview of known genetic alterations and expression profiles amenable for targeted therapy in every histological subtype of SGC. We discuss the remaining knowledge gaps and the implications of these targets for future studies and personalized treatments, thereby aiding clinicians faced with this rare and heterogeneous type of cancer.

Molecular and Morphological Profiling of Lung Cancer: A Foundation for "Next-Generation" Pathologists and Oncologists

The pathological diagnosis of lung cancer has largely been based on the morphological features observed microscopically. Recent innovations in molecular and genetic technology enable us to compare conventional histological classifications, protein expression status, and gene abnormalities. The introduction of The Cancer Genome Atlas (TCGA) project along with the widespread use of the next-generation sequencer (NGS) have facilitated access to enormous data regarding the molecular profiles of lung cancer. The World Health Organization classification of lung cancer, which was revised in 2015, is based on this progress in molecular pathology; moreover, immunohistochemistry has come to play a larger role in diagnosis. In this article, we focused on genetic and epigenetic abnormalities in non-small cell carcinoma (adenocarcinoma and squamous cell carcinoma), neuroendocrine tumor (including carcinoids, small cell carcinoma, and large cell neuroendocrine carcinoma), and carcinoma with rare histological subtypes. In addition, we summarize the therapeutic targeted reagents that are currently available and undergoing clinical trials. A good understanding of the morphological and molecular profiles will be necessary in routine practice when the NGS platform is widely used.

A Rare Case of Pulmonary Mucoepidermoid Carcinoma in an 81-Year-Old Male

BACKGROUND Lung mucoepidermoid carcinoma is a form of non-small cell lung carcinoma that originates from the submucosal glands of the tracheobronchial tree; it is rare and causes 0.1% to 0.2% of lung malignancies. In this article, we report on an occurrence of this condition in an 81-year-old male, which is rare occurrence in this age group. In this case, we found a history of smoking and asbestos exposure which might suggest that exposure to both of these factors can possibly increase the risk for this malignancy. CASE REPORT An 81-year-old male presented with chronic cough and yellow sputum, associated with right upper back pain. The patient was a smoker of 30 packs per year and reported a history of asbestos exposure. He had past medical history of rectal cancer, but no previous history of salivary glands tumors. Physical examination was normal, laboratory investigations were unremarkable. Computed tomography chest showed endobronchial mass with post-obstructive atelectasis. Bronchoscopic evaluation revealed a whitish, endobronchial mass occluding the posterior segment of the right lower lobe. Biopsy showed benign squamous papilloma and malignancy was not excluded as only superficial parts of the mass were obtained. The decision was made to remove the lesion. A right lower lobectomy was done, and histopathology revealed a low grade mucoepidermoid carcinoma; immunohistochemical staining showed tumor cells positive for p40 and p63 supporting the diagnosis. No further adjuvant treatment was recommended, and follow-up imaging was planned for surveillance. CONCLUSIONS Mucoepidermoid carcinoma of the lung is a rare form of non-small cell lung carcinoma. Appropriate diagnosis requires correctly interpreted biopsy results along with immunohistochemical staining results.

Bronchial Mucoepidermoid Carcinoma With the Classic MAML2 Gene Rearrangement in a 2-year-old Boy

Pulmonary mucoepidermoid carcinoma (PMEC) is rare. To date, primary PMEC has not been reported in a child younger than 3 years of age. We report a case of a 2-year-old boy who presented with 3 episodes of wheezing, cough, and fever over a period of 1 month. Radiologic findings were consistent with foreign body aspiration with consequent bronchial obstruction. Bronchoscopy was performed and attempts to retrieve the foreign body resulted in a biopsy of a fleshy lesion. By histology, the lesion was an epithelial neoplasm comprising cells arranged in a nested pattern. The neoplastic cells were round with round nuclei and amphophilic, vacuolated cytoplasm. Our diagnosis was low-grade salivary gland-type carcinoma of the bronchus. The pneumonectomy specimen showed a well-circumscribed, polypoid intrabronchial mass measuring 2.1 cm in greatest dimension. Histologic examination of the tumor showed an admixture of intermediate cells which were predominant, a small number of mucus cells and rare foci of squamous cells. The final diagnosis rendered was a low-grade mucoepidermoid carcinoma of the bronchus. Accurate diagnosis of PMEC can be challenging on limited biopsy material as seen in the case reported here. The use of molecular studies such as MAML2 gene rearrangement may facilitate diagnosis in difficult cases. Increased awareness of this entity and further molecular studies are needed for a better understanding of the pathogenesis of PMEC. To date, the reported age range for primary bronchial mucoepidermoid carcinoma is between 3 years and 78 years. This case represents the youngest patient reported in the English literature.

Interventional Bronchoscopic Therapy in Adult Patients with Tracheobronchial Mucoepidermoid Carcinoma

Background:

Tracheobronchial mucoepidermoid carcinoma (MEC) is a rare airway tumor in adults for which surgery is considered a first-line treatment. However, some patients already lost the best opportunity of a surgical intervention when diagnoses are confirmed, and surgery causes considerable trauma resulting in partial loss of pulmonary function. Moreover, the tumor is resistant to radiotherapy and chemotherapy. These factors make the treatment of tracheobronchial MEC challenging. This study aimed to evaluate the safety and efficacy of interventional bronchoscopic therapy in adult patients with tracheobronchial MEC.

Methods:

We retrospectively analyzed the clinical manifestations, bronchoscopic interventions, complications, and outcomes of 11 adult patients with tracheobronchial MEC. Paired t-test was used to analyze the parameters of the American Thoracic Society Dyspnea Index and the Karnofsky Score before and after the first interventional bronchoscopic therapy.

Results:

All tumors occurred in the main bronchus and were easily visualized by bronchoscopy. After interventional bronchoscopic therapy, the symptoms of all patients showed significant improvement. The American Thoracic Society Dyspnea Index decreased from 1.91 ± 1.22 to 0.27 ± 0.47 (t = 6.708, P < 0.001) and the Karnofsky Score increased from 78.18 ± 16.62 to 95.46 ± 8.20 (t = −5.190, P < 0.001). Bronchoscopic intervention did not result in serious complications or mortality. During the follow-up period between 3 and 96 months after the first therapy, the following results were noted: (1) among the eight patients with low-grade tracheobronchial MEC, only one patient had a relapse and agreed to surgical treatment; (2) among the three patients with high-grade tracheobronchial MEC, one patient required repeated bronchoscopic interventions, one patient died of pulmonary infection, and one patient died of systemic failure owing to tumor metastasis.

Conclusions:

Interventional bronchoscopic therapy, as an alternative treatment, shows promise in some adult patients with low-grade tracheobronchial MEC confined to the bronchus. However, for adult patients with high-grade tracheobronchial MEC, early diagnosis and surgical treatment are still strongly recommended.

Surgery combined with radio-chemotherapy for esophageal mucoepidermoid carcinoma: A case report

RATIONALE

Primary mucoepidermoid carcinoma (MEC) of the esophagus is a rare type of malignant neoplasm. Its morphology resembles that of MEC of the salivary glands. It is characterized by a diffuse mixture of squamous and mucus-secreting glandular carcinoma cells. Due to the low incidence of esophageal MEC, the biological behavior and treatment of this tumor have not been well studied.

PATIENT CONCERNS

In this case report, we describe a case of a 59-year-old man who presented with difficulty in swallowing. Iohexol swallowing revealed a malignant-appearing structure in the inferior-thoracic region.

DIAGNOSES

Biopsy of the lesion under endoscopy demonstrated a mucoepidermoid carcinoma of the esophagus.

INTERVENTIONS

We performed esophagectomy, esophagogastrostomy through the esophageal bed and 2-field lymphadenectomy. Histopathological analysis of the tumor revealed histological characteristics typical of an esophageal MEC. Radio-chemotherapy was administered to this patient.

OUTCOMES

Seventeen months after surgery, an esophageal computed tomography (CT) scan revealed that the wall of esophagus was evenly thickened. However, endoscopic assessment revealed no evidence of recurrence. Further CT scans at 19 and 31 months after surgery also showed a thickened esophageal wall, although endoscopic assessment at 31 months still revealed no esophageal stricture and no evidence of recurrence. The patient is alive with no dysphagia and no evidence of recurrence for over 39 months.

LESSONS

There is little evidence of effective treatment nor guidelines for treatment of esophageal MEC. Although the general prognosis of esophageal MEC is poor, comprehensive treatment of surgery and radio-chemotherapy appeared to be effective in this case. Radio-chemotherapy is a possible treatment option that was shown to have acceptable short-term effects.

Clinicopathological characteristics and molecular analysis of primary pulmonary mucoepidermoid carcinoma: Case report and literature review

Primary pulmonary mucoepidermoid carcinoma (PMEC) is extremely rare. Herein, we report a case of a 71‐year‐old male patient with high‐grade PMEC involving the right upper lobe that was successfully resected via lobectomy. As a result of invasion into the pleural and paratracheal lymph nodes, four cycles of adjuvant chemotherapy with paclitaxel and carboplatin were administered. There were no signs of relapse during 10 months of follow‐up. Furthermore, we reviewed the literature and summarized the surgical approaches, prognostic factors, and underlying genetic mechanisms of PMEC, which will benefit clinical treatment.

[Mucoepidermoid Carcinoma of the Lung: Report of 29 Cases]

BACKGROUND

Pulmonary mucoepidermoid carcinoma (MEC) is an extremely rare pulmonary malignant tumor, its clinical features and conditions of prognosis is not entirely clear. The aim of this study is to discuss clinical features, diagnostic and therapeutic methods, and prognosis of pulmonary MEC.

METHODS

We retrospectively studied 29 pulmonary MEC patients who diagnosed from January 2006 to December 2015 in Affiliated Hospital of Zhengzhou University. The clinical features, prognosis, diagnostic and therapeutic methods were analyzed.

RESULTS

There were 20 patients identified as pulmonary MEC, which constitutes 0.18% of all the lung tumor patients. There were 18 males and 11 females, the median age of the patients was 45 years (range 10-79). There were 17 patients identified as high-grade pulmonary MEC and 12 low-grade. Epidermal growth factor receptor (EGFR) mutation detection was performed in six patients, none was positive. 17 cases was underwent surgery based comprehensive treatment, 12 cases non-operatived treatment. The median follow-up time was 35 (5-114) months in this cohort of 29 patients. During the follow up, incidence of death was found in 17 cases. The overall 1-, 3-, 5-year survival rates were 65.5%, 51.2%, 39.4%, respectively. The median survival time was 37 months.

CONCLUSIONS

The incidence of pulmonary MEC is low, lacking specific clinical characterization. The diagnosis mainly depends on postoperative pathology, aided by immunohistochemical. Surgery is the main treatment method. The majority of pathology was high-grade type. The prognosis of pulmonary MEC closely relates to the pathological types and clinical stage. EGFR-tyrosine kinase inhibitor (EGFR-TKI) is expected to improve the prognosis of pulmonary MEC.

Bronchial mucoepidermoid carcinoma: A case report

INTRODUCTION

Bronchial localization of Mucoepidermoid carcinoma (MEC) is rare. The precise nature of these neoplasms is not yet clear and little is known on the histogenesis and pathogenesis of the disease. Here we present a case of a bronchial MEC with a detailed pathological, immunohistochemical, and molecular analysis.

PRESENTATION OF A CASE

A 46 years old Caucasian male patient was referred to our Unit for fever, non productive cough and dyspnea lasting for two months. The chest CT scan evidenced an 8-mm intraluminal lesion in the left main bronchus, in correspondence of the origin of the lingular segmental bronchus. Multiple biopsies were performed through bronchoscopy, and the diagnosis of a mucoepidermoid carcinoma of the lung was obtained. A left upper lobectomy was performed. The histopathological examination confirmed the preoperative diagnosis and stage (pT1N0M0). No further therapies were employed, given the stage of the disease. The patient is presently free of disease, approximately three years after surgery.

DISCUSSION

The treatment of MECs is usually surgical by traditional or sleeve lobectomy, performed with an open or video-assisted technique, with the aim of an R0 resection. In this stage the prognosis is excellent. Conversely, high grade tumors seems to be particularly aggressive, even more than other NSCLC.

CONCLUSIONS

Low grade type of Bronchial MEC, as our case, is often characterized by an optimal clinical management and prognosis. The lack of EGFR sensitizing mutations does not preclude the use of TKIs, which may be extremely useful in patients non responsive to other therapies.

Mucoepidermoid Carcinoma of the Tracheobronchial Tree

Primary salivary type lung cancers are extremely rare intrathoracic malignancies. Mucoepidermoid tumor is one of the salivary gland tumors that originates from submucosal glands of the tracheobronchial tree. These are very slow-growing low-grade malignant tumors. Surgery is the mainstay of treatment and rarely requires adjuvant therapy. In this case report we describe a 65-year-old woman who presented with a solitary cough yet on further investigation was found to have a mucoepidermoid tumor originating from the hilum of the left lung.

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.

Surgical treatment of mucoepidermoid carcinoma of the lung: 20 years’ experience

Background

Pulmonary mucoepidermoid carcinoma is a rare salivary gland-type neoplasm. We aimed to elucidate the optimal management of this rare condition by reviewing the treatment outcomes of patients at our institution with mucoepidermoid carcinoma of the lung.

Methods

We performed a retrospective review of all patients with pulmonary mucoepidermoid carcinoma who underwent surgical treatment between January 1993 and December 2012. We reviewed the patients’ clinical characteristics and the therapeutic interventions undertaken.

Results

Nine patients were evaluated in this study, 7 of whom were female. The median age of all patients was 54 years (range 10–72 years). Six patients had tumors of a low histologic grade, and the other 3 had high-grade malignancies. Prior to surgery, 2 patients required endobronchial intervention for obstructive pneumonia. Eight patients underwent lobectomy, and one had a bilobectomy. Two patients required bronchoplasty, and one required resection of the left atrium for complete resection of the primary neoplasm. Two patients with advanced disease and high-grade tumors died due to cancer progression. The overall 5-year survival rate was 72.9%. One patient with a high-grade malignancy demonstrated exon 21 mutation of the epidermal growth factor receptor gene.

Conclusions

Complete surgical resection is important for long-term survival in patients with pulmonary mucoepidermoid carcinoma. The techniques of bronchoplasty and extended resection may contribute to better surgical management of this disease. Endobronchial interventions may be considered for the management of obstructive pneumonia prior to surgery.

Landscape of gene fusions in epithelial cancers: seq and ye shall find

Enabled by high-throughput sequencing approaches, epithelial cancers across a range of tissue types are seen to harbor gene fusions as integral to their landscape of somatic aberrations. Although many gene fusions are found at high frequency in several rare solid cancers, apart from fusions involving the ETS family of transcription factors which have been seen in approximately 50% of prostate cancers, several other common solid cancers have been shown to harbor recurrent gene fusions at low frequencies. On the other hand, many gene fusions involving oncogenes, such as those encoding ALK, RAF or FGFR kinase families, have been detected across multiple different epithelial carcinomas. Tumor-specific gene fusions can serve as diagnostic biomarkers or help define molecular subtypes of tumors; for example, gene fusions involving oncogenes such as ERG, ETV1, TFE3, NUT, POU5F1, NFIB, PLAG1, and PAX8 are diagnostically useful. Tumors with fusions involving therapeutically targetable genes such as ALK, RET, BRAF, RAF1, FGFR1-4, and NOTCH1-3 have immediate implications for precision medicine across tissue types. Thus, ongoing cancer genomic and transcriptomic analyses for clinical sequencing need to delineate the landscape of gene fusions. Prioritization of potential oncogenic "drivers" from "passenger" fusions, and functional characterization of potentially actionable gene fusions across diverse tissue types, will help translate these findings into clinical applications. Here, we review recent advances in gene fusion discovery and the prospects for medicine.

Primary Pulmonary Mucoepidermoid Carcinoma: Histopathological and Moleculargenetic Studies of 26 Cases

Introduction

Pulmonary mucoepidermoid carcinoma (PMEC) is an uncommon neoplasm of the lung and the main salivary gland-type lung carcinoma. The aims of this study were to review the clinicopathological and immunohistochemical features of PMEC and characterize the genetic events in PMEC.

Methods

We reviewed the pathology cases in our hospital and found 34 initially diagnosed PMEC cases, 26 of which were confirmed as PMEC after excluding 8 cases of MEC-like pulmonary carcinoma. The clinicopathological characteristics of the 26 PMEC cases and the 8 cases of MEC-like pulmonary carcinoma were retrospectively reviewed. MAML2 rearrangement was detected by fluorescence In Situ Hybridization (FISH). Immunostains of ALK, calponin, collagen IV, CK7, EGFR, HER2, Ki-67, Muc5Ac, p63, p40, and TTF-1 were performed. DNA was extracted from 23 cases of PMEC. Mutation profiling of the EGFR, KRAS, BRAF, ALK, PIK3CA, PDGFRA, and DDR2 genes were carried out using next-generation sequencing (NGS), Sanger sequencing, and quantitative polymerase chain reaction (QPCR) in 9 successfully amplified cases.

Results

Twenty-six cases of PMEC (18 low-grade, 8 high-grade) included 13 men and 13 women aged 12–79 years. Twenty-two cases had a central/endobronchial growth pattern, and 4 cases had a peribronchial growth pattern. Immunohistochemically, CK7, Muc5Ac, p40, and p63 were positive in all cases (26/26);EGFR was positive in 11 cases (11/26); TTF-1, Calponin, HER2 and ALK were negative in all cases (0/26). MAML2 rearrangement was identified in 12 of 18 PMEC cases. No mutations were detected in any of the 7 genes in the 9 cases that qualified for mutation analysis. Twenty-three PMEC patients had follow-up information with a median interval of 32.6 months. Both the 5- and 10-year overall survival rates (OS) were 72.1%, and a high-grade tumor was an adverse prognostic factor in PMEC. There were 8 cases of MEC-like pulmonary carcinoma aged 36–78 years: 2 cases were located in the bronchus, and 6 cases were located in the lung. p63 and TTF-1 were positive in all cases (8/8), p40 was positive in 5 cases (5/8), and ALK was positive in 5 cases (5/8). No cases of MAML2 rearrangement were detected, but there were 5 cases of ALK rearrangement.

Conclusions

PMEC is a primary malignant pulmonary tumor with a relatively good prognosis that is historically characterized by the presence of mucous cells and a lack of keratinization. There are distinct differences between PMEC and MEC-like pulmonary carcinoma in tumor location preference, immunophenotype, and molecular genetics, and the differential diagnosis is critical due to the therapeutic and prognostic considerations.

Molecular genetic studies on EGFR, KRAS, BRAF, ALK, PIK3CA, PDGFRA, and DDR2 in primary pulmonary adenoid cystic carcinoma

BACKGROUND

Pulmonary adenoid cystic carcinoma (PACC) is an uncommon neoplasm of the lung but represents the predominant type of salivary gland-type lung carcinoma. Only a few studies have focused on the genetic events associated with PACC. The aim of this study was to characterize the genetic events associated with PACC.

FINDINGS

We reviewed 24 cases of primary PACC between 2000 and 2014, including 21 cases reported in our previous study and three new cases added in 2014. Mutation profiling of the EGFR, KRAS, BRAF, ALK, PIK3CA, PDGFRA, and DDR2 genes was performed using next-generation sequencing, Sanger sequencing, and quantitative polymerase chain reaction in 9 successfully amplified cases. The 24 cases of PACC included 7 men and 17 women, aged 24-74 years (mean, 50.8 years). All the cases were located in the trachea or bronchus. No mutations were detected in any of the seven genes in the nine cases that qualified for mutation analysis, and the results using different methods were consistent.

CONCLUSIONS

The data presented in this work suggest that EGFR, KRAS, BRAF, ALK, PIK3CA, PDGFRA, and DDR2 may not be driver genes in primary pulmonary adenoid cystic carcinoma.

Primary intraosseous mucoepidermoid carcinoma of the jaw: Reappraisal of The MD Anderson Cancer Center experience

BACKGROUND

Mucoepidermoid carcinoma arises from major or minor salivary glands, making up 10% of salivary gland tumors. Intraosseous mucoepidermoid carcinomas are rare, and make up only 2% to 3% of all mucoepidermoid carcinomas. The t(11;19) and its CRTC1-MAML2 fusion gene transcript have been identified in mucoepidermoid carcinoma and are associated with a subset of mucoepidermoid carcinomas. The extent to which the transcript influences disease features and patient survival is unclear.

METHODS

We conducted a retrospective analysis of records for clinical features, surgical interventions, and prognoses. Reverse transcriptase-polymerase chain reaction (RT-PCR) and fluorescence in situ hybridization (FISH) used to assess the t(11;19) fusion gene in intraosseous mucoepidermoid carcinoma.

RESULTS

Twenty-five patients with intraosseous mucoepidermoid carcinoma treated between 1998 and 2013 were identified. The t(11;19) fusion gene transcript CRTC1-MAML2 manifested in 9 intraosseous mucoepidermoid carcinomas, whereas is was not detected in another 9 intraosseous carcinomas. Although the incidence of this fusion in mucoepidermoid carcinoma varies, it is generally accepted that more than 50% of this entity manifest the CRTC1-MAML2.

CONCLUSION

Intraosseous mucoepidermoid carcinoma diagnosis should be based on clinical and pathologic manifestations and complete resection is the first choice for patient treatment. The need for neck dissection and adjuvant treatment are debatable. Radiotherapy may improve prognosis and may be recommended in the postoperative period. Primary intraosseous mucoepidermoid carcinoma can manifest the fusion transcript in a subset of tumors. © 2015 Wiley Periodicals, Inc. Head Neck 38: E1312-E1317, 2016.

Efficacy of Bronchoscopic Therapies for Bronchial Mucoepidermoid Carcinoma in Children: Results from Six Patients

Aims and Background

Bronchial mucoepidermoid carcinoma is a rare disease in children, and lobectomy is traditionally considered as a first-line treatment. As the tumor is characterized by intraluminal growth, low malignancy and superficial infiltration of bronchial walls, bronchoscopic interventional therapy may provide an alternative treatment with favorable results. The aim of the study was to evaluate the efficacy and safety of bronchoscopic therapies for bronchial mucoepidermoid carcinoma in children.

Methods and Study design

Clinical manifestations, multiple bronchoscopic interventions and outcomes in 6 children with bronchial mucoepidermoid carcinoma were retrospectively analyzed.

Results

The median age was 8.7 years (range 4 to 12 years). All the tumors were located in the lobar bronchus and were detected by computerized tomography. Diagnoses of low-grade mucoepidermoid carcinoma were made based on biopsies obtained via bronchoscopy. Five tumors were classified as intraluminal type and successfully eradicated by carbon dioxide cryotherapy and argon plasma coagulation under bronchoscopy. The other tumor in patient 3 was classified as the mixture type and could not be removed by a bronchoscopic, so left upper lobectomy was performed. For each patient, interventional procedures were conducted on the average for 6 times. No recurrence was detected by bronchoscopic inspections or computed tomography scans during follow-ups for 16-72 months.

Conclusions

Multiple bronchoscopic procedures, as alternative treatments, are effective in removing bronchial mucoepidermoid carcinoma mucoepidermoid carcinoma in children without any major complications.

[Mucoepidermoid tracheo-bronchial tumors in adulthood. A series of 22 cases]

INTRODUCTION

Mucoepidermoid tumours (TME) are rare tumours arising from the submucosal glands of the tracheobronchial tree. The majority of these tumours develop in a benign fashion but some of them are malignant. The latter can be easily mistaken for adenosquamous carcinomas.

PATIENTS AND METHOD

We have reviewed 22 patients suffering from TME observed over a period of 25 years. Two arose from the trachea and 20 from the cartilaginous bronchi; 12 of these tumours had macroscopic and histological criteria of low-grade malignancy, 4 had macroscopic and 6 macroscopic and microscopic criteria of high grade malignancy.

RESULTS

Prognosis of the latter was very poor and no survival observed after 6 years follow-up, a behavior similar to that observed in non-small cell lung carcinomas and adenosquamous carcinomas.

CONCLUSION

The best treatment of these orphan tumours remains surgery.

Secretory hyperresponsiveness and pulmonary mucus hypersecretion

The term bronchial hyperresponsiveness is generally used to describe a heightened airway smooth muscle bronchoconstrictor response measured by bronchoprovocation testing. However, the airway also responds to inflammation or bronchoprovocation with increased mucus secretion. We use the term "secretory hyperresponsiveness" to mean increased mucus secretion either intrinsically or in response to bronchoprovocation. This is not the same as retained phlegm or sputum. Unlike smooth muscle contraction, which is rapidly reversible using a bronchodilator, mucus hypersecretion produces airflow limitation that reverses more slowly and depends upon secretion clearance from the airway. Certain groups of patients appear to have greater mucus secretory response, including those with middle lobe syndrome, cough-dominant ("cough-variant") asthma, and severe asthma. Secretory hyperresponsiveness also is a component of forms of lung cancer associated with bronchorrhea. An extreme form of secretory hyperresponsiveness may lead to plastic bronchitis, a disease characterized by rigid branching mucus casts that obstruct the airway. Secretory hyperresponsiveness and mucus hypersecretion appear to be related to activation of the extracellular-regulated kinase 1/2, signaling through the epidermal growth factor receptor, or secretory phospholipases A2. Recognizing secretory hyperresponsiveness as a distinct clinical entity may lead to more effective and targeted therapy for these diseases.

Mixed lung mucoepidermoid carcinoma and adenocarcinoma with identical mutations in an epidermal growth factor receptor gene

Lung cancers presenting two different histologic types are relatively rare. This paper presents a case report of mixed lung cancer comprising mucoepidermoid carcinoma and conventional adenocarcinoma, a combination that has not been reported previously. These two carcinomas showed distinct morphologic and immunohistochemical features. However, gene analysis revealed identical mutations in each component, which indicates they possess a monoclonal origin. Specifically, we identified the same mutation in exon 19 of the epidermal growth factor receptor gene. Molecular analysis further substantiated a monoclonal origin with divergent differentiation, as opposed to the collision of discrete tumors.

Mucoepidermoid carcinoma of lung masquerading as urothelial carcinoma of bladder

BACKGROUND

Mucoepidermoid carcinoma (MEC) of the lung is a rare subtype of non-small cell lung cancer. There is no consensus regarding optimal management for this disease.

CASE REPORT

We present a case of MEC of the lung in a 75 year-old female with a history of superficial urothelial carcinoma of the bladder. The patient was found to have an asymptomatic lung mass. Initial biopsy suggested metastatic recurrence of urothelial carcinoma and therefore, cisplatin and gemcitabine chemotherapy was administered prior to surgical resection. Pathological analysis of the resected specimen confirmed a diagnosis of stage IIIA MEC with focal high-grade features including transitional cell-like areas. Adjuvant radiotherapy was administered due to a positive microscopic resection margin. No chemotherapy was given due to lack of supporting data. The patient developed widespread metastatic disease 3 months following completion of radiotherapy and died 1 month later.

CONCLUSION

This case demonstrates the possibility of dual pathology in cases where metastatic disease is suspected. The use of small tissue samples may complicate diagnosis due to the heterogeneity of malignant tumours.

MAML2 rearrangement in primary pulmonary mucoepidermoid carcinoma and the correlation with FLT1 expression

Introduction

Primary pulmonary mucoepidermoid carcinoma (PMEC) is an uncommon neoplasm with remarkable resemblance to mucoepidermoid carcinoma of the salivary glands. The latter has been shown to harbor t(11,19) resulting in MECT1-MAML2 fusion, which may be of diagnostic and prognostic values. However, the importance of such feature in PMEC has not been well studied.

Methods

We detected MAML2 rearrangement using fluorescence in situ hybridization (FISH) in tissue samples from 42 cases of PMEC and 40 of adenosquamous carcinoma (ASC), and the expression of potential downstream targets of MECT1-MAML2, including HES1, FLT1 and NR4A2 with immunohistochemistry (IHC). The findings were then examined regarding the clinicopathological parameters and patient outcomes.

Results

FISH analysis revealed MAML2 rearrangement in 50% of the PMEC cases, and such property was prominent in considerable younger patients (33 versus 60 years; p = 0.001) and restricted to cases of low and intermediate grades. IHC analysis showed that FLT1 and HES1 were expressed at lower level in MAML2 rearranged group than MAML2 non-rearranged group (p<0.001 and p = 0.023, respectively). Survival analysis showed significant correlation between MAML2 rearrangement and overall survival (p = 0.023) or disease-free survival (p = 0.027) as well as correlation between FLT1 and overall survival (p = 0.009).

Conclusions

MAML2 rearrangement appears frequent in PMEC and specific with this tumor. Both the presence of MAML2 rearrangement and absence of FLT1 tend to confer a favorable clinical outcome. These findings suggest that molecular detection of MAML2 rearrangement combined with FLT1 may be of important clinical value for PMEC.

Clinicopathological analysis of pulmonary mucoepidermoid carcinoma

Background

Mucoepidermoid carcinoma (MEC) of the lung is a rare malignant neoplasm. We aimed to investigate clinicopathological features, therapies, and prognoses of eight MEC cases.

Methods

Eight patients underwent surgical treatment for pulmonary MEC between 2005 and 2012 at the Thoracic Surgical Department of West China Hospital, Sichuan, China. The clinical data, radiological manifestation, treatment strategy, pathological findings, and prognoses of all patients were analyzed retrospectively.

Results

Among the eight cases (four males and four females), the age of patients ranged from 35 to 71 years (mean age 50.67 years). Two tumors were located in the upper lobes and three masses were located in the lower lobes. The other three lumps were located in the left main bronchus, middle segmental bronchus of the right lobe, and trachea, respectively. The characteristics of the tumors were consistent with low grade MEC (n = 6) and high grade MEC (n = 2). All of the patients were sent for oncological evaluations, and three patients with N1 or N2 disease received chemotherapy. One of the patients died from brain metastasis at 15 months. Seven of the eight patients were alive at the time of evaluation. The median survival time was 40 (range 8 to 88) months.

Conclusion

Mucoepidermoid tumors have to be treated by radical surgery with lymph node sampling and dissection. Patients with low grade tumors can be expected to be cured following complete resection. Careful histological typing plays a key role in prediction of late results, and further studies are needed.

Mucoepidermoid carcinoma of the lung: a case report and literature review

Introduction. Mucoepidermoid carcinoma (MEC) of the lung is a rare form of lung cancer that is classified into low grade and high grade based on histological features. Surgical resection is the primary treatment for low-grade MEC with excellent outcomes, while high-grade MEC is a more aggressive form of malignancy. Clinical Case. We report a case of a 46-year-old woman who presented with dyspnea on exertion. Imaging studies revealed a mass involving the right upper lobe bronchus. Bronchoscopy, surgical resection, and pathological examination revealed a low-grade MEC with tumor-free margins. No adjuvant treatment was given. Discussion. Primary pulmonary MEC is a rare type of lung cancer with only few reported cases. This patient illustrates a typical presentation for low-grade MEC wherein surgical resection is considered curative. In contrast, high-grade MEC is a more aggressive malignancy with a poorer outcome. The role of targeted therapy directed against EGFR or a novel CRTC1-MAML2 fusion protein expressed in some high-grade tumors is yet to be determined.

Aberrantly activated AREG-EGFR signaling is required for the growth and survival of CRTC1-MAML2 fusion-positive mucoepidermoid carcinoma cells

Salivary gland tumors (SGT) are a group of highly heterogeneous head and neck malignancies with widely varied clinical outcomes and no standard effective treatments. The CRTC1-MAML2 fusion oncogene, encoded by a recurring chromosomal translocation t(11;19)(q14-21;p12-13), is a frequent genetic alteration found in >50% of mucoepidermoid carcinomas (MEC), the most common malignant SGT. In this study, we aimed to define the role of the CRTC1-MAML2 oncogene in the maintenance of MEC tumor growth and to investigate critical downstream target genes and pathways for therapeutic targeting of MEC. By performing gene expression analyses and functional studies via RNA interference and pharmacological modulation, we determined the importance of the CRTC1-MAML2 fusion gene and its downstream AREG-EGFR signaling in human MEC cancer cell growth and survival in vitro and in vivo using human MEC xenograft models. We found that CRTC1-MAML2 fusion oncogene was required for the growth and survival of fusion-positive human MEC cancer cells in vitro and in vivo. The CRTC1-MAML2 oncoprotein induced the upregulation of the epidermal growth factor receptor (EGFR) ligand Amphiregulin (AREG) by co-activating the transcription factor CREB, and AREG subsequently activated EGFR signaling in an autocrine manner that promoted MEC cell growth and survival. Importantly, CRTC1-MAML2-positive MEC cells were highly sensitive to EGFR signaling inhibition. Therefore, our study revealed that aberrantly activated AREG-EGFR signaling is required for CRTC1-MAML2-positive MEC cell growth and survival, suggesting that EGFR-targeted therapies will benefit patients with advanced, unresectable CRTC1-MAML2-positive MEC.

Molecular testing guideline for selection of lung cancer patients for EGFR and ALK tyrosine kinase inhibitors: guideline from the College of American Pathologists, International Association for the Study of Lung Cancer, and Association for Molecular Pathology

OBJECTIVE

To establish evidence-based recommendations for the molecular analysis of lung cancers that are required to guide EGFR- and ALK-directed therapies, addressing which patients and samples should be tested, and when and how testing should be performed.

PARTICIPANTS

Three cochairs without conflicts of interest were selected, one from each of the 3 sponsoring professional societies: College of American Pathologists, International Association for the Study of Lung Cancer, and Association for Molecular Pathology. Writing and advisory panels were constituted from additional experts from these societies.

EVIDENCE

Three unbiased literature searches of electronic databases were performed to capture published articles from January 2004 through February 2012, yielding 1533 articles whose abstracts were screened to identify 521 pertinent articles that were then reviewed in detail for their relevance to the recommendations. EVIDENCE was formally graded for each recommendation.

CONSENSUS PROCESS

Initial recommendations were formulated by the cochairs and panel members at a public meeting. Each guideline section was assigned to at least 2 panelists. Drafts were circulated to the writing panel (version 1), advisory panel (version 2), and the public (version 3) before submission (version 4).

CONCLUSIONS

The 37 guideline items address 14 subjects, including 15 recommendations (evidence grade A/B). The major recommendations are to use testing for EGFR mutations and ALK fusions to guide patient selection for therapy with an epidermal growth factor receptor (EGFR) or anaplastic lymphoma kinase (ALK) inhibitor, respectively, in all patients with advanced-stage adenocarcinoma, regardless of sex, race, smoking history, or other clinical risk factors, and to prioritize EGFR and ALK testing over other molecular predictive tests. As scientific discoveries and clinical practice outpace the completion of randomized clinical trials, evidence-based guidelines developed by expert practitioners are vital for communicating emerging clinical standards. Already, new treatments targeting genetic alterations in other, less common driver oncogenes are being evaluated in lung cancer, and testing for these may be addressed in future versions of these guidelines.

Molecular testing guideline for selection of lung cancer patients for EGFR and ALK tyrosine kinase inhibitors: guideline from the College of American Pathologists, International Association for the Study of Lung Cancer, and Association for Molecular Pathology

OBJECTIVE

To establish evidence-based recommendations for the molecular analysis of lung cancers that are that are required to guide EGFR- and ALK-directed therapies, addressing which patients and samples should be tested, and when and how testing should be performed.

PARTICIPANTS

Three cochairs without conflicts of interest were selected, one from each of the 3 sponsoring professional societies: College of American Pathologists, International Association for the Study of Lung Cancer, and Association for Molecular Pathology. Writing and advisory panels were constituted from additional experts from these societies.

EVIDENCE

Three unbiased literature searches of electronic databases were performed to capture articles published published from January 2004 through February 2012, yielding 1533 articles whose abstracts were screened to identify 521 pertinent articles that were then reviewed in detail for their relevance to the recommendations. Evidence was formally graded for each recommendation.

CONSENSUS PROCESS

Initial recommendations were formulated by the cochairs and panel members at a public meeting. Each guideline section was assigned to at least 2 panelists. Drafts were circulated to the writing panel (version 1), advisory panel (version 2), and the public (version 3) before submission (version 4).

CONCLUSIONS

The 37 guideline items address 14 subjects, including 15 recommendations (evidence grade A/B). The major recommendations are to use testing for EGFR mutations and ALK fusions to guide patient selection for therapy with an epidermal growth factor receptor (EGFR) or anaplastic lymphoma kinase (ALK) inhibitor, respectively, in all patients with advanced-stage adenocarcinoma, regardless of sex, race, smoking history, or other clinical risk factors, and to prioritize EGFR and ALK testing over other molecular predictive tests. As scientific discoveries and clinical practice outpace the completion of randomized clinical trials, evidence-based guidelines developed by expert practitioners are vital for communicating emerging clinical standards. Already, new treatments targeting genetic alterations in other, less common driver oncogenes are being evaluated in lung cancer, and testing for these may be addressed in future versions of these guidelines.

Molecular testing guideline for selection of lung cancer patients for EGFR and ALK tyrosine kinase inhibitors: guideline from the College of American Pathologists, International Association for the Study of Lung Cancer, and Association for Molecular Pathology

OBJECTIVE

To establish evidence-based recommendations for the molecular analysis of lung cancers that are required to guide EGFR- and ALK-directed therapies, addressing which patients and samples should be tested, and when and how testing should be performed.

PARTICIPANTS

Three cochairs without conflicts of interest were selected, one from each of the 3 sponsoring professional societies: College of American Pathologists, International Association for the Study of Lung Cancer, and Association for Molecular Pathology. Writing and advisory panels were constituted from additional experts from these societies.

EVIDENCE

Three unbiased literature searches of electronic databases were performed to capture articles published from January 2004 through February 2012, yielding 1533 articles whose abstracts were screened to identify 521 pertinent articles that were then reviewed in detail for their relevance to the recommendations. Evidence was formally graded for each recommendation.

CONSENSUS PROCESS

Initial recommendations were formulated by the cochairs and panel members at a public meeting. Each guideline section was assigned to at least 2 panelists. Drafts were circulated to the writing panel (version 1), advisory panel (version 2), and the public (version 3) before submission (version 4).

CONCLUSIONS

The 37 guideline items address 14 subjects, including 15 recommendations (evidence grade A/B). The major recommendations are to use testing for EGFR mutations and ALK fusions to guide patient selection for therapy with an epidermal growth factor receptor (EGFR) or anaplastic lymphoma kinase (ALK) inhibitor, respectively, in all patients with advanced-stage adenocarcinoma, regardless of sex, race, smoking history, or other clinical risk factors, and to prioritize EGFR and ALK testing over other molecular predictive tests. As scientific discoveries and clinical practice outpace the completion of randomized clinical trials, evidence-based guidelines developed by expert practitioners are vital for communicating emerging clinical standards. Already, new treatments targeting genetic alterations in other, less common driver oncogenes are being evaluated in lung cancer, and testing for these may be addressed in future versions of these guidelines.