Outcome of Primary Lung Salivary Gland-Type Carcinoma: A Population-Based Study.

Introduction. Primary pulmonary salivary gland-type carcinomas are rare malignancies arising from minor salivary gland tissue in the lower respiratory tract. Given their rarity, constituting <1% of all primary lung malignancies, their epidemiological features and outcomes remain poorly documented. This study analyzed data from the National Cancer Institute's Surveillance, Epidemiology, and End Results (SEER) database to identify primary pulmonary salivary gland carcinomas, including the most prevalent tumor types. Methods. All patients diagnosed with mucoepidermoid carcinoma, adenoid cystic carcinoma, and epithelial-myoepithelial carcinoma, with the lung designated as the primary site between 1975 and 2019, were subject to analysis. Overall and disease-specific survival were calculated using Kaplan-Meier curves and Cox proportional hazards models. Results. The study identified 323 mucoepidermoid carcinoma, 284 adenoid cystic carcinoma, and 6 epithelial-myoepithelial carcinoma diagnosed as pulmonary salivary gland-type carcinoma. An analysis of age distribution revealed a unimodal pattern for both mucoepidermoid carcinoma and adenoid cystic carcinoma, with most patients diagnosed after age 40. Most patients were Caucasians (77% for mucoepidermoid carcinoma and 83% for adenoid cystic carcinoma). Both disease-specific and overall survival were worse for patients diagnosed at the age of 60 years or above. Race or sex did not significantly impact patient survival. High-grade mucoepidermoid carcinoma demonstrated a significantly worse prognosis than low or intermediate-grade mucoepidermoid carcinoma. Conclusion. A comprehensive review of clinical and epidemiological features of pulmonary salivary gland-type carcinomas reveals that the age of diagnosis and tumor grade are the most significant factors in determining patient survival.

Clinical presentation and treatment of four children with pulmonary mucoepidermoid carcinoma.

Primary lung cancer in childhood is extremely rare, with an incidence rate of less than 2/100,0000, and pulmonary mucoepidermoid carcinoma (PMEC), is even rarer. Their symptoms are usually not specific, and there are no guidelines for their management, which makes their clinical management a challenge for pediatricians. The purpose of this report is to discuss the clinical presentation, positive signs, examinations, pathological characteristics, surgical modalities, chemotherapy regimens, and prognosis in children. The clinical data of four patients diagnosed with PMEC at the Children's Hospital of Chongqing Medical University from June 2021 to November 2022 were retrospectively analyzed, and their clinical features, treatment, and prognosis were summarized. Among them, two were male and two were female; their ages ranged from 3 years and 10 months to 10 years and 11 months, and all were staged according to tumor node metastasis classification (TNM). Immunohistochemical tests were performed in all children, among which four cases were positive for cytokeratin (CK), two cases were positive for CK7, four cases were positive for p63, about 5-10% of tumor cells were positive for Ki67. Among the four children, three had surgery alone and one had surgery + chemotherapy. All four children are presently living, with no evidence of tumor recurrence or metastasis. PMEC in children is very rare, and its age of onset and symptoms are not specific, and there is no obvious correlation with gender. Its diagnosis mainly relies on pathomorphological diagnosis, and immunohistochemical detection has no specific performance. The prognosis of children with PMEC is related to the clinical stage and whether surgery is performed. Whether further chemotherapy or radiotherapy is needed for patients who cannot undergo surgical resection and for those who have a combination of distant metastases requires further clinical studies.

Clinical presentation and treatment of 4 children with pulmonary mucoepidermoid carcinomaLung cancer in childhood is extremely rare, occurring at a rate of less than 2/1000000, and a type of lung cancer called pulmonary mucoepidermoid carcinoma (PMEC), is even rarer. The symptoms are usually not specific, and there are no guidelines for its management, which is a challenge for doctors. The purpose of this report is to discuss the signs and symptoms medical examinations, disease characteristics, surgical procedures, chemotherapy regimens and prognosis in children with pulmonary mucoepidermoid carcinoma. The clinical data of four patients diagnosed with pulmonary mucoepidermoid carcinoma at the Children's Hospital of Chongqing Medical University from June 2021 to November 2022 were analyzed, and their clinical features, treatment and prognosis were summarized. All four children are currently alive, and there is no recurrence or spread of the tumor after treatment. We have discussed various aspects of the disease, such as the rate of occurrence, causes, signs and symptoms, the way in which it might be diagnosed and treated, and the survival rate after operation, hoping to provide some insights for future work.

Left lower lobe sleeve resection for the clear cell variant of pulmonary mucoepidermoid carcinoma: A case report.

BACKGROUND: Pulmonary mucoepidermoid carcinoma (PMEC) is a rare malignancy that arises from minor salivary glands within the tracheobronchial tree. The clear cell variant of PMEC is exceptionally uncommon and presents notable diagnostic challenges, primarily attributable to its morphological similarity to other tumors containing clear cells. CASE SUMMARY: A 22-year-old male, formerly in good health, came in with a two-month duration of persistent cough and production of sputum. Subsequent imaging and bronchoscopy examinations revealed a 2 cm tumor in the distal left main bronchus, which resulted in complete atelectasis of the left lung. Further assessment via positron emission tomography/computed tomography scans and endoscopic biopsy confirmed the primary malignant nature of the tumor, characterized by clear cell morphology in most of the tumor cells. The patient underwent a left lower lobe sleeve resection accompanied by systematic mediastinal lymph node dissection. Molecular pathology analysis subsequently revealed a CRTC3-MAML2 gene fusion, leading to a definitive pathological diagnosis of the clear cell variant of PMEC, staged as T2N0M0. After surgery, the patient experienced a smooth recovery and exhibited no signs of recurrence during the one-and-a-half-year follow-up period. CONCLUSION: This article describes an unusual case of a clear cell variant of PMEC characterized by the presence of a CRTC3-MAML2 gene fusion in a 22-year-old male. The patient underwent successful left lower lobe sleeve resection. This case underscores the distinctive challenges associated with diagnosing and treating this uncommon malignancy, underscoring the importance of precise diagnosis and personalized treatment strategies.

MSCT findings of primary Pulmonary mucoepidermoid carcinoma.

OBJECTIVES: To improve diagnostic accuracy of pulmonary mucoepidermoid carcinoma (PMEC) through multi-detector computed tomography (MSCT) findings. METHODS: MSCT findings of 27 histopathologically confirmed PMEC cases were retrospectively analyzed, including the location, size, margin, density, enhancement of the lesion and accompanying signs. RESULTS: Among the 27 PMEC cases, 6 (6/27, 22.2%) were the large airway pattern, 14 were (14/27, 51.9%) the pulmonary hilum pattern, and 7 (7/27, 26.9%) were the peripheral pattern. Among those 20 cases with central pattern(6 large airway and 14 pulmonary hilum patterns), 6 presented mild enhancement, 4 moderate enhancement, 5 severe enhancement, 5 heterogeneous enhancement, and 3 with calcification. 7 cases with peripheral patterns were presented as solid pulmonary nodules and masses, 3 with severe enhancement, 1 with moderate enhancement and 3 with mild enhancement. Four cases accompanied by lymph nodal metastasis, and 7 cases with distant organ metastasis. Age(t = -3.132, p = 0.005), enlarged lymph node (x2 = 9.281, p = 0.005), and distant metastasis(x2 = 7.816, p = 0.008) were statistically significant in the low-grade group and high-grade group. CONCLUSIONS: MSCT images of PMEC patients demonstrated some characteristic findings, which would help improve the diagnostic accuracy of the disease.

Pulmonary Mucoepidermoid Carcinoma With Multiple Paraneoplastic Syndromes.

Pulmonary mucoepidermoid carcinoma (PMEC) is rare and challenging to diagnose. Its association with paraneoplastic syndromes is poorly described. It is also uncommon for a patient with lung cancer to present with multiple paraneoplastic syndromes. We report a case of a patient with metastatic high-grade PMEC associated with three paraneoplastic syndromes, namely, humoral hypercalcemia of malignancy, ectopic ACTH syndrome, and paraneoplastic leukemoid reaction.

Pulmonary mucoepidermoid carcinoma in children: two case reports and a review of the literature.

Pulmonary mucoepidermoid carcinoma (PMEC) is a rare tumor, particularly in children, and its clinical manifestations vary. When the tumor is small, it may be asymptomatic; however, with larger tumors, patients may present with symptoms such as recurring pneumonia, atelectasis, persistent cough, chest pain, and even hemoptysis. PMEC appears as an exophytic intrabronchial mass. This study aims to report on the clinical manifestations, imaging findings, treatment approaches, and prognosis of two children diagnosed with PMEC at our hospital between January 2018 and December 2022. The age of onset for both children was 9 years, and the masses were located in the right upper lobe bronchi. Following surgical treatment, both patients showed a good prognosis. In addition, we conducted a comprehensive review of the relevant literature to enhance the overall understanding of PMEC.

Pulmonary mucoepidermoid carcinoma in children: a rare diagnosis not to be overlooked - case report.

Pulmonary mucoepidermoid carcinoma (PMEC) in children is a rare entity. The diagnosis is often unrecognized, often treated as pneumonia, a more frequent diagnosis at this age. Case presentation: The authors report in this article, the case of a 12-year-old child with a clinical history of chronic cough evolving for 6 months with recurrent episodes of pneumonia. The presence of a foreign body was suggested on the thoracic computed tomography (CT). PMEC was histopathologically determined on biopsy. Fluorine-18-fluorodesoxyglucose positron emission tomography (18 F-FDG PET)/CT was performed as part of the extension work-up prior to surgical management. Clinical discussion: Preoperative imaging with 18F-FDG PET/CT seems to be a valuable tool for predicting tumor grade, nodal stage, and postsurgical prognosis in mucoepidermoid carcinoma. PMEC patients with high 18F-FDG PET/CT uptake may need extensive mediastinal lymph node dissection and adjuvant therapy. Conclusion: PMEC has different presentations depending on the degree of tumor differentiation on PET/CT whose input in the management of these rare cancers requires further studies.

Successful complete tumor resection for pulmonary mucoepidermoid carcinoma by thoracoscopic right upper lobectomy with intraoperative bronchoscopy: A pediatric case report.

INTRODUCTION AND IMPORTANCE: Mucoepidermoid carcinoma presents as an exophytic endobronchial mass that induces obstructive symptoms often followed by distal collapse atelectasis of the lung parenchyma. CASE PRESENTATION: A six-year-old girl had recurrent bacterial pneumonia and atelectasis of the right upper lobe. Computed tomography revealed a 30-mm mass in the anterior segment of the right upper lobe with an obstructed trachea and peripheral atelectasis. A minor salivary gland tumor was suspected, so thoracoscopic right upper lobectomy (RUL) was performed. Intraoperative bronchoscopy showed no protrusion of the tumor into the tracheal lumen. We confirmed that there was no injury to the middle lobe branch and no residual tumor via bronchoscopy before transection of the trachel bronchus of the right upper lobe. The histological type was low-grade mucoepidermoid carcinoma. The postoperative course was uneventful, and no recurrence was evident after one year. CLINICAL DISCUSSION: Primary pulmonary cancers in children are extremely rare. Mucoepidermoid carcinoma is the most common disease in pediatric primary lung tumors but remains relatively rare. Mucoepidermoid carcinoma of the tracheobronchial tree sometimes requires sleeve resection. Intraoperative bronchoscopy helped determine the exact position of the tumor. The value of intraoperative bronchoscopy for sparing the lung parenchyma and preserving as much of the respiratory function as possible. Intraoperative bronchoscopy should be actively performed in cases of pediatric lobectomy, especially those involving tracheobronchial tumors. CONCLUSION: Intraoperative bronchoscopy allowed for complete RUL without residual tumor or injury of the middle lobe bronchus.

Clinical, laboratory, pathological, and radiological characteristics and prognosis of patients with pulmonary salivary gland-type tumors.

PURPOSE: Primary pulmonary salivary gland-type tumor (PSGT) included two main subtypes, pulmonary adenoid cystic carcinoma (PACC) and pulmonary mucoepidermoid carcinoma (PMEC). The purpose of this study was to compare the similarities and differences between these two subtypes and to identify independent risk factors for the prognosis of PSGT patients. METHODS: This study screened patients with a pathological diagnosis of PSGT in Beijing Chaoyang Hospital between 2010 and 2021. The clinical, pathological, radiological, laboratory test, and other characteristics were collected, and t, nonparametric and chi-squared tests were used to compare the differences in clinical characteristics of the two subtypes. COX univariate and multivariate analyses were used to explore prognostic-related risk factors. RESULTS: A total of 62 patients with PSGT were included in our center over a 12-year period. There were 26 PMEC patients and 36 PACC patients. There were differences in the clinical, pathological, and radiological features of the two tumor subtypes. Univariate analysis showed that weight loss, chemotherapy, white blood cells, lymphocytes, red blood cells, total protein, and total bilirubin might be related to the prognosis in PSGT patients. Multivariate results showed that lymphocytes (p = 0.031), red blood cells (p = 0.047), total protein (p = 0.032), and total bilirubin (p = 0.010) were independent prognostic risk factors. Chemotherapy (HR 4.452; 95% CI 1.723-11.503; p = 0.002) might be associated with progression-free survival (PFS). CONCLUSION: The two subtypes of PSGT had significantly different clinical, laboratory, pathological, and radiological features. However, there was no significant difference in the prognosis of patients with PMEC and PACC subtypes. Cox univariate and multivariate analyses showed that levels of lymphocytes, erythrocytes, total protein and total bilirubin in the peripheral blood of PSGT patients might be related to patient overall survival. Chemotherapy might also be associated with PFS.

Pulmonary mucoepidermoid carcinoma in the Chinese population: A clinical characteristic and prognostic analysis.

Background: Mucoepidermoid carcinoma is dominant in salivary glands and rarely occurs in the lung. Primary pulmonary mucoepidermoid carcinoma is a type of non-small-cell lung cancer, but the prognostic factors in Chinese patients remain controversial. This investigation aimed to review cases of pulmonary mucoepidermoid carcinoma, analyse the prognosis of this disease. Methods: Patients with pathologically proven pulmonary mucoepidermoid carcinoma were screened at the Department of Respiratory and Critical Care Medicine at the Peking University Third Hospital, Beijing Friendship Hospital Affiliated to Capital Medical University, and Peking University Cancer Hospital for inclusion in this retrospective study. Demographic data, including age, sex, clinical symptoms, smoking, alcohol consumption, allergies, family history, imaging findings, fibrobronchoscopy findings, surgical procedures, tumour location and pathologic stage, were collected. Telephone follow-up was conducted for all patients not lost to follow-up. The associations of sex, age, smoking, tumour differentiation, tumour size, lymph node metastasis, pathologic stage, and patient survival were retrospectively analysed. Kaplan-Meier, univariate and multivariate analysis curves were used to analyse patient prognosis and prognostic factors. Results: Thirty-one patients, comprising 23 males and 8 females, were enrolled in the analysis. The mean age was 60.77 ± 11.44 years. The first symptom was nonspecific, with cough being the most common (21/31, 67.77%); smokers accounted for 16 of the 31 patients, and ten patients had a history of alcohol consumption. Overall, the tumours could occur in either lobe of the lungs; tumours occurred in the right lung in 19/31 patients, and tumours occurred in the left lung in 12/31 patients. Regarding TNM stage, 10 patients had stage I (5 with stage 1a, 5 with stage 1b), 5 had stage II (1 with stage 2a, 4 with stage 2b), 3 had stage III (1 with stage 3a, 2 with stage 3b), and 13 had stage IV (10 with stage 4a, 3 with stage 4b). In our Cox univariate survival analysis of patients with pulmonary mucoepidermoid carcinoma, we found that TNM stage IV, degree of differentiation and lymph node metastasis were risk factors for pulmonary mucoepidermoid carcinoma and that degree of differentiation was an independent risk factor. Conclusion: The clinical, radiographical and pathological features of pulmonary mucoepidermoid carcinoma were systemically analysed and summarized, and the degree of differentiation and lymph node metastasis, as well as prognostic factors in addition to clinical stage, were confirmed.

Pulmonary mucoepidermoid carcinoma: A clinicopathological study of 45 patients.

Pulmonary mucoepidermoid carcinoma (PMEC) is uncommon. The purpose of this study was to evaluate the clinicopathological features, diagnostic criteria, treatment options, and prognostic factors relating to primary PMEC. Clinical data on 45 patients with primary PMEC were collected and analyzed retrospectively at Tianjin Medical University General Hospital and the First People' Hospital of Longquanyi District Chengdu from January 2008 to December 2020. The 45 patients (25 males and 20 females) ranged in age from 22 to 72 years, with a median age of 49 and an average age of 47.7. All the patients underwent surgery, with 32 receiving only surgery and 13 receiving both surgery and postoperative chemotherapy. A total of 34 instances of low-grade tumors and 11 cases of high-grade tumors were discovered during postoperative pathological diagnosis. Forty-five patients were followed for 13 to 78 months, and four died during this period. In all four instances, a lung infection unrelated to the tumor was determined to be the cause of death. The MAML2 gene translocation was detected in 40 of 45 patients, with 34 of them testing positive. Radical surgery with lymph node dissection is an efficient treatment for PMEC. The prognosis is poor for patients with advanced disease, a negative MAML2 gene translocation, lymph node metastases, and high-grade tumors.

Gene Expression and Mutational Landscape in a PMEC Patient With Low to Intermediate-High Grade Transition.

Primary pulmonary mucoepidermoid carcinoma (PMEC) is a very rare form of lung carcinoma. Due to the low incidence, little is known about its inherent genetic variation characteristics. The uniform treatment for PMEC has not been determined. In this case, we present a 45-year-old male with stage IA PMEC. The surgical specimens contained changes from low- to intermediate-to-high grade. We performed integrative analysis of whole-exome sequencing (WES-seq) and messenger ribonucleic acid sequencing (RNA-seq) to compare the molecular changes in the different lesions. Molecular testing exhibits the specimens harboring CRTC3-MAML2 fusion. The copy number gain of PDPK1 is only present in high-grade regional specimens. We also explored the level of immune infiltration by CIBERSORT. To our knowledge, this is the first report to describe a case of PMEC in the low- to intermediate-high-grade transition with multiomics analysis.

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.

Photodynamic therapy for pulmonary mucoepidermoid carcinoma.

Pulmonary mucoepidermoid carcinoma (PMEC) are rare, accounting for 0.1-0.2% of all malignant lung tumors. Furthermore, endobronchial lesions are rare and are more commonly found in the segmental or lobar bronchi. We present, to the best of our knowledge, the first case of successful treatment with photodynamic therapy (PDT) for PMEC. A 77-year-old male presented with cough and hemosputum for 4 months. Chest computed tomography showed a mass in the right intermediate bronchus. Endobronchial biopsy revealed a diagnosis of PMEC. An optimal surgical technique to preserve respiratory function was desirable as most of the tumor emerged from the bronchial glands in the central airways and was of low-grade type. Hence, PDT was performed. Repeat bronchoscopies were performed 5 years after the PDT and showed no evidence of tumor recurrence. PDT is more likely to be effective for low-grade PMECs that are visible on bronchoscopy.

Nomogram for predicting the survival rate of primary pulmonary mucoepidermoid carcinoma patients: a retrospective study based on SEER database.

BACKGROUND: Primary pulmonary mucoepidermoid carcinoma (PMEC) is a rare malignant tumor, and the clinical manifestations lack specificity. The study evaluates the prognostic factors and constructs a practicable nomogram to estimate the individualized survival status for PMEC patients. METHODS: Surveillance, Epidemiology, and End Results (SEER) database was used to selected eligible patients between 1975 and 2016. The baseline characteristics including age, sex, race, marital status, tumor stage, differentiated degree, tumor laterality, primary tumor site, tumor size, lymph node metastases status, distant metastases status, surgery, chemotherapy, and radiation. We identified independent variables to build 3-, 5-, 10-year overall survival (OS) and cancer-specific survival (CSS) nomograms by univariate and multivariate analyses. RESULTS: A total of 438 PMEC patients met our selection criteria. In multivariate analysis, age, tumor stage, differentiated grade, tumor size, lymph node metastases status, distant metastases status, surgery and radiation were involved in the nomogram. The C-index (0.887 (95% CI: 0.863-0.911), calibrate plots and ROC curves (AUC =0.941, 0.951, 0.935 for 3-, 5-, 10-year OS, respectively) indicated the satisfied accuracy and practicability of our nomograms. Compared to TNM system, our model also showed a superior prediction (IDI =0.167, 0.171, 0.172, P<0.001). CONCLUSIONS: We built OS (CSS) nomograms that can accurately estimate individualized survival time and identify the risk classification of PMEC.

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

BACKGROUND: Pulmonary 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. METHODS: In 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. RESULTS: The 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. CONCLUSION: The 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 characteristics and prognostic analyses of 87 patients with pulmonary mucoepidermoid carcinoma].

Objective: To investigate the clinicopathological characteristics, therapy and prognosis of patients with pulmonary mucoepidermoid carcinoma. Methods: The clinical data of 87 patients diagnosed as pulmonary mucoepidermoid carcinoma at The First Affiliated Hospital of Zhengzhou University from April 2011 to May 2016 were retrospectively analyzed. The clinicopathological features were summarized and the prognoses were analyzed. Results: Among the 87 patients with lung mucoepidermoid carcinoma, 53 were male and 34 were female, the gender ratio between men and women was 1.56∶1.The ages of patients were from 16 to 79 years and the median age was 52.5 years. Seventeen cases were diagnosed as stage Ⅰ, 28 cases were stage Ⅱ, 26 cases were stage Ⅲ, 16 cases were stage Ⅳ.Thirty-six patients were examined by immunohistochemistry, of which 29 cases were cytokeratin (CK) 5/6 positive, 29 cases were CK7 positive, 10 cases were CK positive, 28 cases were p63 positive, 14 cases were p40 positive, 17 cases were thyroid transcription factor-1 (TTF-1) positive, 11 cases were NapsinA positive, 2 cases were epithelial membrane antigen (EMA) positive, 4 cases were CK8/18 positive, 3 cases were surfactant proteins A (SPA) positive, 1 case was CAM5.2 positive and 1 case was CK14 positive. Among the 87 patients, 34 cases were treated by operation alone, 23 cases were treated by operation combined with chemotherapy, 5 cases were treated by radiotherapy combined with chemotherapy, 14 cases were treated by chemotherapy alone, 2 cases were treated by particle implantation combined with chemotherapy, 2 cases were treated by local radiofrequency hyperthermia combined with chemotherapy, and 7 cases without special treatment.Five patients with brain metastasis were treated with cerebral radiotherapy combined with sequential chemotherapy. The 1-year, 2-year and 5-year survival rates of 87 patients were 90.7%, 81.6% and 46.3%, respectively. The median survival time was 60 months. The prognoses of patients with lung mucoepidermoid carcinoma were related with the clinical stage, smoking and operative therapy (all P<0.05). Conclusions: The age distribution of patients with pulmonary mucoepidermoid is a wide range, the incidence of male is higher than that of female. The diagnosis of pulmonary mucoepidermoid carcinoma mainly relies on the morphological diagnosis and the immunohistochemical detection is non-specific. The prognoses of patients with lung mucoepidermoid carcinoma are related with clinical stage, smoking and operative therapy. For patients who are inoperable and with single distant metastasis, local radiotherapy, other local treatment and chemotherapy can significantly improve their prognoses.

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.

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.

CT features and differential diagnosis of primary pulmonary mucoepidermoid carcinoma and pulmonary adenoid cystic carcinoma.

BACKGROUND: The differential diagnosis of primary pulmonary mucoepidermoid carcinoma (PMEC) and pulmonary adenoid cystic carcinoma (PACC) is difficult, because both tumors could be similar in terms of certain characteristics on CT. METHODS: The CT findings from 24 cases of PMEC and 30 cases of PACC were retrospectively analyzed. According to the position of the lesion in airway, we divided these cases into three types: central, hilar, and peripheral. RESULTS: In PMEC, there were 7 cases of central type, 14 cases of hilar type, and 3 cases of peripheral type. And, 57.1% PMEC cases of the hilar type were accompanied by distal bronchial dilatation with mucoid impaction. Patchy areas of low density were observed in 79.2% cases of PMEC. The solid part of most lesions showed moderate (37.5%) or severe enhancement (45.8%). However, in PACC, there were 24 cases of central type, 3 cases of hilar type, and 3 cases of peripheral type. PACC had more cases of central type than PMEC. Moreover, longitudinal extent greater than 3 cm was observed in 62.5% PACC cases of the central type, while infiltration of the luminal perimeter more than 1/2 perimeter was observed in 95.8% PACC cases of the central type. Patchy areas of low density were observed in 26.7% cases of PMEC. In PACC cases, the solid part of 76.7% lesions showed slight enhancement. Cavities could be observed in PMEC, but not in PACC. CONCLUSIONS: PMEC and PACC have different CT features in various airway locations. PMEC is usually the hilar type, accompanied by distal bronchial dilatation with mucoid impaction. However, PACC is usually the central type, with longitudinal extent greater than 3 cm and infiltration of the luminal wall more than 1/2 perimeter. Patchy areas of low density and moderate or severe enhancement are more prominent in PMEC. However, slight enhancement is more common in PACC.