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

Evolving Diagnostic Approach of Pulmonary Salivary Gland-type Tumors

Pulmonary salivary gland-type, although bear resemblance to their salivary gland counterparts, present a diagnostic challenge due to their rarity. Clinical features overlap with lung carcinoma; however, management strategies and outcomes are distinct. Onus falls on the pathologist to avoid misinterpretation of small biopsies especially in young, nonsmokers with slow growing or circumscribed endobronchial growths. A combination of cytokeratin, myoepithelial immunohistochemical markers, and identification of signature molecular alteration is invaluable in differentiation from lung cancers and subtyping the pulmonary salivary gland-type tumor.

Clinico-pathological study of esophageal mucoepidermoid carcinoma: a 10-year survival from a single center

BACKGROUND

Mucoepidermoid Carcinoma of the Esophagus (MECE) is a relatively rare tumor type, with most of the current data derived from case reports or small sample studies. This retrospective study reports on the 10-year survival data and detailed clinicopathological characteristics of 48 patients with esophageal MEC.

METHODS

Data were collected from 48 patients who underwent curative surgery for esophageal MEC at the Fourth Hospital of Hebei Medical University between January 1, 2004, and December 31, 2020. These were compared with contemporaneous cases of Esophageal Squamous Cell Carcinoma (ESCC) and Esophageal Adenocarcinoma (EAC). Using the Kaplan-Meier method and multivariate Cox regression analysis, we investigated the clinicopathological factors affecting the survival of patients with MEC.

RESULTS

The incidence of MECE was predominantly higher in males, with a male-to-female ratio of approximately 7:1. The mid-thoracic segment emerged as the most common site of occurrence. A mere 6.3% of cases were correctly diagnosed preoperatively. The lymph node metastasis rate stood at 35.4%. The overall 1-year, 3-year, 5-year, and 10-year survival rates for all patients were 85.4%, 52.1%, 37.0%, and 31.0%, respectively. Post 1:1 propensity score matching, no significant statistical difference was observed in the Overall Survival (OS) between MEC patients and those with Esophageal Squamous Cell Carcinoma (ESCC) and Esophageal Adenocarcinoma (EAC) (P = 0.119, P = 0.669). Univariate analysis indicated that T staging and N staging were the primary factors influencing the prognosis of esophageal MEC.

CONCLUSIONS

MECE occurs more frequently in males than females, with the mid-thoracic segment being the most common site of occurrence. The rate of accurate preoperative endoscopic diagnosis is low. The characteristic of having a short lesion length yet exhibiting significant extramural invasion may be a crucial clinicopathological feature of MECE. The OS of patients with MEC does not appear to significantly differ from those with esophageal squamous carcinoma and adenocarcinoma.

Endobronchial Glandular Papilloma With Atypical Histologic Characteristics: A Case Report and Literature Review

Papilloma of the lung is a rare benign entity and can be solitary or multiple. Solitary papilloma is subclassified into three categories: squamous papilloma, glandular papilloma, and mixed squamous and glandular papilloma. Glandular papilloma is the rarest subtype among them and occurs mostly in the sixth decade without any relation to smoking, syndrome, or infection. Histology is characterized by mixture of pseudostratified, columnar, nonciliated, mucinous epithelium-lined papillary fronds without any mitoses, necrosis, or atypia. The differential diagnosis can be broad depending upon the histologic features present in a particular case and may include both benign and malignant entities. We present here a patient with glandular endobronchial papilloma showing unusual clinical history and atypical histologic features, which required extensive immunohistochemical evaluation to establish a final diagnosis.

Mucoepidermoid carcinoma-a rare salivary gland-type tumor of the breast: are we dealing with primary or secondary?-a case report and literature review

Background

Salivary gland-like tumors are extremely unusual in the breast, and their histology is very similar to primary salivary gland neoplasms. Mucoepidermoid carcinoma (MEC), a common salivary gland tumor, displays an infrequent occurrence in the breast, accounting for a mere 0.2-0.3% incidence. Given its rarity, it is critical to accurately distinguish it from metastatic cases before diagnosing it as a primary breast MEC for appropriate treatment. Currently, there is no consensus on the treatment of MEC, and there is a paucity of literature highlighting the ideal treatment modality, especially for estrogen receptor (ER)-positive cancers. Therefore, the aim of our case report was to underscore the diagnostic process, surgical and adjunctive treatments for our patient with ER-positive, progesterone receptor (PR)-negative and human epidermal growth factor receptor 2 (HER2)-negative MEC while also conducting a literature review to contribute to the limited existing data.

Case Description

A 67-year-old African American woman presented with a lobulated 3.1-cm left breast mass on mammography, for which she underwent ultrasound-guided core needle biopsy that revealed invasive carcinoma with squamous differentiation. The carcinoma was ER-positive, PR-negative and HER2-negative. Subsequently, she underwent a lumpectomy with sentinel lymph node biopsy. Her final pathology revealed an intermediate-grade MEC with negative lymph nodes. She had a past medical history of benign salivary gland tumor, as well as a family history of BReast CAncer gene 1 (BRCA1)-associated breast cancer in her daughter.

Conclusions

MEC of the breast is a rare tumor with a relatively favorable overall prognosis. The early and precise diagnosis of this condition plays a pivotal role in formulating effective treatment strategies and ensuring positive survival rates. Nonetheless, future studies are recommended to further explore the role of surgical approaches and adjuvant therapy to improve treatment outcomes.

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.

Current diagnosis and treatment of salivary gland-type tumors of the lung

Salivary gland-type tumors of the lung are thought to originate from the submucosal exocrine glands of the large airways. Due to their rare occurrence, reports of their study are limited to small-scale or case reports. Therefore, daily clinical practices often require a search for previous reports. In the last 20 years, several genetic rearrangements have been identified, such as MYB::NF1B rearrangements in adenoid cystic carcinoma, CRTC1::MAML2 rearrangements in mucoepidermoid carcinoma, EWSR1::ATF1 rearrangements in hyalinizing clear cell carcinoma and rearrangements of the EWSR1 locus or FUS (TLS) locus in myoepithelioma and myoepithelial carcinoma. These molecular alterations have been useful in diagnosing these tumors, although they have not yet been linked to molecularly targeted therapies. The morphologic, immunophenotypic, and molecular characteristics of these tumors are similar to those of their counterparts of extrapulmonary origin, so clinical and radiologic differential diagnosis is required to distinguish between primary and metastatic disease of other primary sites. However, these molecular alterations can be useful in differentiating them from other primary lung cancer histologic types. The management of these tumors requires broad knowledge of the latest diagnostics, surgery, radiotherapy, bronchoscopic interventions, chemotherapy, immunotherapy as well as therapeutic agents in development, including molecularly targeted agents. This review provides a comprehensive overview of the current diagnosis and treatment of pulmonary salivary gland tumors, with a focus on adenoid cystic carcinoma and mucoepidermoid carcinoma, which are the two most common subtypes.

MAML2 gene rearrangement occurs in all Warthin-like mucoepidermoid carcinoma: A reappraisal in a series of 29 cases

Background

Warthin-like Mucoepidermoid carcinoma (MEC) is a new and rare morphological variant of MEC, with only a few case reports in the literature. The clinicopathological, molecular features and bio-behaviors of Warthin-like MEC has not been studied extensively. We reappraisal all Warthin-like MEC patients diagnosed and treated at our hospital.

Methods

Patient characteristics including clinicopathological features, genetic aberrations, treatment, and prognostic information were assessed and evaluated.

Results

Twenty-nine Warthin-like MEC patients were identified, 19 patients were female (65.5 %), and 10 were male (34.5 %). The patients' age varied widely from 8 to 68 years (mean 42.3 years). Genetic aberrations of MAML2 rearrangement were detected in all Warthin-like MEC patients, which suggesting this genetic event is the unique feature of Warthin-like MEC. Twenty-five patients (86.2 %) were assessed as having a low-stage disease (I/II), and four (13.8 %) as having high-clinical stage disease (III/IV). More than half of the patients (16/29) underwent only partial sialoadenectomy; 2 patients underwent extended sialoadenectomy, and 11 patients underwent extended sialoadenectomy with cervical lymph node dissection. After a median follow-up time of 73 months (5-128 months), Twenty-eight patients were alive without recurrence at the end of the follow-up period, one patient died 1 year after surgery due to lung metastasis.

Conclusion

Our data suggested that most Warthin-like MEC exhibited mild clinicopathological course and less aggressive bio-behavior, and an aggressive bio-behavior seemed to be very rare. In addition, in the salivary gland, MAML2 rearrangement seems to be a unique molecular feature of salivary Warthin-like MEC.

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.

Mucoepidermoid carcinoma of the lung with hemoptysis as initial symptom: A case report

BACKGROUND

Mucoepidermoid carcinoma of the lung is a rare malignant tumor, accounting for 0.1%-0.2% of all lung malignancies. It is a primary salivary gland tumor of the lung. Surgical resection is the primary treatment for pulmonary mucoepidermoid carcinoma, for which there has been no standardized treatment strategy. This article reports a case of a young woman with pulmonary mucoepidermoid carcinoma with hemoptysis as the first symptom.

CASE SUMMARY

A 24-year-old female patient presented with "4 d of hemoptysis" as the chief complaint. She had no special history and denied any smoking or drinking history. Physical examination revealed that the vital signs were stable and scattered small wet rales were heard in the left lung. After admission, the lung tumor markers were checked, and no abnormalities were found. After completing the bronchoscopy, a spherical lesion was observed at the main bronchus 1.5 cm away from the protubercle, with obvious pulsation and little blood seepage on the surface, and histopathological biopsy results showed acute and chronic inflammation. She was transferred to the Department of Thoracic Surgery for surgical treatment on the 16th day after admission. After exclusion of surgical conjunctures, the patient underwent resection of the tumor in the left main bronchus with single-pore video-assisted thoracic surgery on the 19th day after admission. The postoperative histopathological biopsy results showed mucoepidermoid carcinoma of the lung. The patient and her family refused to complete genetic testing and she was discharged from the hospital on the 8th day after surgery. During the follow-up period, the patient experienced shortness of breath after feeling active and had no special discomfort.

CONCLUSION

We have documented a case of moderately differentiated mucoepidermoid lung cancer with hemoptysis as the first symptom to improve clinicians' understanding of the disease and provide a new dimension of thinking for its future diagnosis and treatment.

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.

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.

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.

Therapeutic strategies to overcome EGFR mutations as acquired resistance mechanism in ALK-rearranged non-small-cell lung cancer: Case Reports

Introduction

ALK tyrosine kinase inhibitors (ALK TKIs) have improved prognosis in ALK-rearranged (ALK ⁺) non-small-cell lung cancer (NSCLC). However, drug resistance mechanisms occur inevitably during the course of treatment leading to disease progression. Activation of epidermal growth factor receptor (EGFR) bypass signaling pathway is an uncommon cause of acquired resistance to ALK TKIs.

Method

We present two patients with EML4-ALK rearranged NSCLC, developing an acquired EGFR resistance mutation after receiving multiple lines of ALK TKIs.

Results

While preclinical models have showed encouraging data, there is a critical need for clinical studies on treatment strategies to overcome this drug resistance. Three real-life therapeutic approaches were used in this report: i) using brigatinib, an inhibitor targeting both ALK and EGFR tyrosine kinases; ii) combining two ALK TKIs together; and iii) delivering doublet platinum chemotherapy. In case 1, time to treatment failure (TTF) was 9.5 months with brigatinib; in case 2, TTF was 10 months with combined TKIs (osimertinib and brigatinib), whereas TTF with chemotherapy was only 2 months. Tolerability profile TKIs combotherapy was acceptable.

Conclusion

These case reports underline the therapeutic complexity of EGFR-acquired resistance mutation in ALK⁺ NSCLC and offers some leads to solve this real-life clinical challenge.

Adenosquamous Carcinomas and Mucinous Adenocarcinoma of the Minor Salivary Glands: Immunohistochemical and Molecular Insights

There is confusion about the diagnosis, histogenesis and taxonomical efforts regarding adenosquamous carcinomas (ASCs) and mucinous adenocarcinomas (MACs), especially with calls for reconsidering the nature of high-grade mucoepidermoid carcinoma (MEC). This study aims to compare the genetic profiles of ASCs and MACs that have been previously reported in the literature and investigate if either ASC or MAC is closer in genetic mutations to high-grade MEC. Systematic searches in the NCBI, Web of Science, and Scopus databases were performed between January 2000 and August 2022. The retrieved genetic mutations were processed and annotated. Protein–protein network analysis was conducted for each neoplasm. The results were viewed and discussed in terms of molecular oncogenesis of ASCs and MACs at different topographies. Molecular profile mapping was conducted by annotating all the retrieved genes for each neoplasm using genetic network analysis (Cystoscape software program). The genetic profile of each lesion was compared to that of high-grade MEC. To conclude, both genetic profiles do not tend to intersect specifically with high-grade MEC, except for the generic mutations commonly detected in all high-grade head and neck tumors. However, the availability of data on the molecular profile of each lesion limits the generalizability of the findings of this study.

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.

Postoperative radiotherapy for thymus salivary gland carcinoma: A case report

BACKGROUND

Salivary gland cancer is a rare disease in which cancer cells form in the tissues of the salivary glands. It mostly occurs in the glands that have secretion functions, such as the parotid gland, sublingual gland and submandibular gland. This is very rare when it occurs in other nonsecreting glands. Here, we report one case of salivary gland carcinoma occurring in the thymus and discuss related diagnoses and treatment progress.

CASE SUMMARY

One 33-year-old middle-aged man presented with a thymus mass without any clinical symptoms when he underwent regular physical examination. Later, the patient was admitted to the hospital for further examination. Computed tomography (CT) showed that there was a mass of 3 cm × 2.8 cm × 1.5 cm in the thymus area. The patient had no symptom of discomfort or tumor- related medical history before. After completing the preoperative examinations, it was confirmed that the patient had indications for surgery. The surgeon performed a transthoracoscope "thymectomy + pleural mucostomy" for him. During the operation, the tumor tissue was quickly frozen, and the symptomatic section showed a malignant tumor. The final pathological result suggested thymus salivary gland carcinoma- mucoepidermoid carcinoma (MEC). In the second month after surgery, we performed local area radiotherapy for the patient, with a total radiation dose of 50.4 Gy/28Fx. After 12 mo of surgery, the patient underwent positron emission tomography-CT examination, which indicated that there was no sign of tumor recurrence or metastasis. After 16 mo of operation, CT scan re-examination showed that there was no sign of tumor recurrence or metastasis. As of the time of publication, the patient was followed up for one and a half years. He had no sign of tumor recurrence and continued to survive.

CONCLUSION

The incidence of MEC in the thymus is low, and its diagnosis needs to be combined with clinical features and imaging methods. Histopathological analysis plays a key role in the diagnosis of the disease. Patients with early-stage disease have a good prognosis and long survival period. In contrast, patients with advanced-stage disease have a poor prognosis and short survival period. Combining radiotherapy and chemotherapy in inoperable patients may prolong survival.

Primary lung carcinoma in children and adolescents: An analysis of the European Cooperative Study Group on Paediatric Rare Tumours (EXPeRT)

BACKGROUND

Primary lung carcinoma is an exceptionally rare childhood tumour, as per definition of the European Cooperative Study Group on Paediatric Rare Tumours (EXPeRT), with an incidence of 0.1-0.2/1,000,000 per year. Little is known about the clinical characteristics of children with primary lung carcinoma, a gap which this joint analysis of the EXPeRT group aimed to fill.

PATIENTS AND METHODS

We performed a retrospective case series of children (aged 0-18 years) with primary lung carcinoma, as collected through the EXPeRT databases between 2000 and 2021. We recorded relevant clinical characteristics including treatment and outcome.

RESULTS

Thirty-eight patients were identified with a median age of 12.8 years at diagnosis (range: 0-17). Mucoepidermoid carcinoma (MEC) was the most frequent entity (n = 20), followed by adenocarcinoma (n = 12), squamous cell carcinoma (n = 4), adenosquamous carcinoma (n = 1) and small-cell lung cancer (n = 1). Patients with MEC presented rarely with lymph node metastases (2/20 cases). Overall, 19/20 patients achieved long-lasting remission by surgical resection only. Patients with other histologies often presented in advanced stages (14/18 TNM stage IV). With multimodal treatment, 3-year overall survival was 52% ± 13%. While all patients with squamous cell carcinoma died, the 12 patients with adenocarcinoma had a 3-year overall survival of 64% ± 15%.

CONCLUSIONS

Primary lung carcinomas rarely occur in children. While the outcome of children with MEC is favourable with surgery alone, patients with other histotypes have a poor prognosis, despite aggressive treatment, highlighting the need to develop new strategies for these children, such as mutation-guided treatment.

Incidences and characteristics of primary lung malignancies in childhood in Germany: An analysis of population-based data from German cancer registries

BACKGROUND

Primary lung malignancies are a heterogeneous group of cancers that occur very rarely in childhood. Due to limited knowledge of their epidemiologic and clinical features, these tumors present a challenge to the treating physicians. This study aimed to increase the knowledge about the occurrence of primary lung malignancies in childhood in Germany.

MATERIALS AND METHODS

Pseudonymized data of cases recorded at the German Center for Cancer Registry Data (ZfKD) between 1990 and 2017 were retrieved. Primary lung malignancies were identified using the ICD- and ICD-O classification. Numbers were compared to those reported to the German Childhood Cancer Registry (GCCR). Crude incidence rates were calculated using the ZfKD database.

RESULTS

A total of 168 patients diagnosed with primary lung malignancies in the age below 19 years were identified from the ZfKD. The median age at diagnosis was 13 years. The most common tumor entities were lung carcinoids (n = 49), lung carcinoma (n = 36), and pleuropulmonary blastoma (n = 14). An unexpected accumulation of lung cancer cases was noted in the first year of life without a clearly specified histopathological diagnosis. A substantial discrepancy in the numbers of primary lung malignancies between ZfKD and GCCR was found.

CONCLUSIONS

We present population-based data on the occurrence of primary childhood lung malignancies in Germany, which were more frequent than previously anticipated but likely remained underreported. For better understanding and optimal treatment of these entities, cancer registration needs to be improved through mandatory reporting to the GCCR and regular data sharing between GCCR, population-based and clinical cancer registries.

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.

A Young Child With Recurrent Pneumonia and Hemoptysis During the COVID-19 Pandemic

In July 2020, a previously healthy 6-year-old boy was evaluated in a pulmonary clinic in New York after two episodes of pneumonia in the previous 3 months. For each episode, the patient presented with cough, fever, and hemoptysis, all of which resolved with antibiotic therapy and supportive care. The patient never experienced dyspnea during these episodes of pneumonia. He was asymptomatic at the current visit. The patient had no history of travel, sick contacts, asthma, or bleeding disorders.

[Primary malignant salivary gland-type tumors of the lung: clinico-pathological study of 10 cases]

Primary pulmonary salivary gland-type tumors are rare and characterized by a specific clinico-pathological manifestation. They are proximal tumors affecting young subjects and not associated with smoking. For optimal management, it is important to distinguish them from other bronchopulmonary tumors, with which they don´t share either biology or treatment and outcome. We conducted a retrospective study, including all primary malignant salivary gland-type tumors of the lung, over a period of 32 years, from January 1987 to December 2019. We collected data from the medical records of 10 patients: 5 men and 5 women (sex ratio 1). The average age of our patients was 47.4 years. In all cases radiological examinations showed proximally located nodular tumor ranging in size from 1 to 5.8 cm. Histological examination objectified mucoepidermoid carcinoma (6 out of 10 cases). All patients had localized or locally advanced tumors, with the exception of one case of metastatic mucoepidermoid carcinoma. Pulmonary salivary gland-type tumors correspond to a heterogeneous group of tumours. They are not very aggressive but are associated with a high frequency of recurrences and late metastases, requiring long-term monitoring.

Salivary Gland-type Tumors of the Lung

CONTEXT.—

Salivary gland-type tumors (SGTs) of the lung represent a distinct group of lung neoplasms. Pulmonary SGTs often pose diagnostic challenges, especially in small biopsy and cytology samples because of limited sample volume and overlapping morphology among pulmonary SGTs, metastatic SGTs of head and neck origin, and other lung tumors.

OBJECTIVE.—

To identify the clinical characteristics, histomorphology, immunophenotypic features, and molecular alterations that are crucial for the diagnosis and differential diagnosis of pulmonary SGTs, especially in small biopsy and cytology specimens.

DATA SOURCES.—

Literature review and authors' personal practice experience.

CONCLUSIONS.—

An accurate diagnosis of pulmonary SGTs can be achieved by careful evaluation of clinical findings and histomorphology in conjunction with immunohistochemical studies and molecular analysis.

Primary lung carcinoma in children and adolescents - Clinical characteristics and outcome of 12 cases from the German registry for rare paediatric tumours (STEP)

OBJECTIVES

Primary lung carcinomas are very rare paediatric tumours with an incidence of < 2/1.000.000 per year. They are clinically and histologically heterogeneous, and there are no therapeutic guidelines for this age group. Therefore, they represent a challenge for treating physicians. This analysis was performed to expand knowledge on characteristics, treatment and prognosis of primary lung carcinoma in paediatric patients.

MATERIAL AND METHODS

Between 2009 and 2019, twelve children and adolescents with lung carcinoma were identified in the prospective German registry for rare paediatric tumours (STEP). Data were analysed for histopathological entities, symptoms, diagnostics, therapy, clinical course and outcome.

RESULTS

Mucoepidermoid carcinoma (MEC) was the most frequent entity (n = 7), followed by adenocarcinoma (n = 2), squamous cell carcinoma (SCC; n = 2) and adenosquamous carcinoma (n = 1). Patients presented with non-specific symptoms and often, they were initially mistreated for airway infections. Patients with MEC showed no metastases and were successfully treated with complete resection. Patients with adenocarcinoma and SCC were older than 16 years of age at diagnosis. While patients with SCC presented with distant metastases and died within one year after diagnosis, those with adenocarcinoma and adenosquamous carcinoma achieved complete remission after multimodal treatment.

CONCLUSIONS

Presenting symptoms of lung carcinomas are unspecific and therefore, diagnostic evaluation and treatment are difficult. In the absence of carcinogen exposure, etiology seems to differ from adult lung carcinoma. Children diagnosed with MEC face a favourable outcome. In contrast, patients with prognostically unfavourable adenocarcinoma and SCC might benefit from molecular profiling and targeted therapies. International collaboration for the establishment of treatment protocols adjusted for distinct features of primary lung carcinoma in childhood is essential.

Pulmonary mucoepidermoid lung carcinoma in pediatric confused with asthma

Pulmonary mucoepidermoid carcinoma (PMEC) is an extremely rare tumor of the respiratory system. The clinical presentation of PMEC is variable and nonspecific, including cough, hemoptysis, and wheezing, and may mimic other symptoms of pneumonia or asthma. Here, we present a case of PMEC in a 12-year-old male who was diagnosed with and treated for asthma for 2 years. The patient presented with symptoms of respiratory failure that did not respond to steroids or bronchodilator medications. Chest computed tomography (CT) scans revealed an endotracheal tumor. The patient underwent complete tumor resection, with no signs of recurrence 6 months after treatment.

Mutational landscape of primary pulmonary salivary gland-type tumors through targeted next-generation sequencing

OBJECTIVES

Primary pulmonary salivary gland-type tumors (PSGTs) mainly comprise of mucoepidermoid carcinoma (MEC) and adenoid cystic carcinoma (ACC), which are rare and molecularly poorly understood. This study aimed to profile the molecular alterations of PSGTs via targeted next-generation sequencing (NGS).

MATERIAL AND METHODS

Immunohistochemistry was used to screen PSGTs in 32 patients and MAML2 and MYB rearrangements were detected using fluorescence in situ hybridization. 1021-Genepanel of targeted NGS was conducted to profile genomic mutations in all the PSGT patients.

RESULTS

Among the 32 patients, 25 had MEC and 7 had ACC. MAML2 and MYB rearrangements were detected in 80.0% (20/25) of the MEC and 71.4% (5/7) of the ACC patients. Among the MEC patients, 10 (40.0%) had ≥1 mutation, and 6 of them had 11 isolated mutations with abundance >5%, namely NFE2L2, MYOD1, INPP4B, CCND2, SNTG1, HSPD1, TGFBR1, RBM10, NOTCH4, ASXL1, and PTPRD mutations. The remaining 4 patients had 9 mutations with abundance <5%, namely KMT2A, PDCD11, FLT1, BRCA2, APC, SLX4, FOXP1, FGFR1, and HRAS mutations. All the ACC patients had mutations, which were enriched in 5 pathways including the PI3K and NOTCH pathways, chromatin and cytoskeleton remodeling, and DNA damage. These results explain PSGTs harbor distinct driver features of MAML2 or MYB rearrangement, accompanied with wide mutational diversity with very low rate of somatic mutation. Several important pathways, including the NOTCH and PI3K pathways, and chromatin remodeling could be targeted to improve the survival in patients with ACC.

Mucoepidermoid lung carcinoma in a pediatric patient confused with pneumonia

Mucoepidermoid carcinoma (MEC) is a common type of salivary gland malignancy; however, rarely, MEC can arise from the lung. This disease has a non-specific presentation and is often overlooked. Histologically, MEC can be classified into low-grade and high-grade forms. Surgical resection is the optimal treatment for low-grade tumors. In this article, we report a case of MEC in a 5-year-old girl who was initially misdiagnosed with pneumonia. The histological results revealed MEC. Thus, clinicians and radiologists should consider the possibility of this rare entity in patients who fail to respond to antibiotic treatments, even among the pediatric population.

Primary pulmonary mucoepidermoid carcinoma: Cyto-histologic correlation and review of the literature

Preoperative fine needle aspiration diagnosis and cyto-histologic correlation of primary pulmonary mucoepidermoid carcinoma have rarely been described in detail in the literature. A 26-year old male presented at our institution with cough, bloody sputum, and a 4.3 cm left lower lobe lung mass. He was accurately diagnosed with pulmonary mucoepidermoid carcinoma on preoperative aspiration cytology. The patient subsequently proceeded to left lower lobectomy, confirming the diagnosis. In this article, we present a detailed report of primary pulmonary mucoepidermoid carcinoma describing the cytologic and histologic morphologic features, its differential diagnosis with review of the literature.

Breast mucoepidermoid carcinoma: a case report and review of literature

Breast mucoepidermoid carcinoma (MEC) is clinically rare, with an estimated incidence of 0.2-0.3% of all primary breast tumors. To date, only 41 cases have been reported in the literature. Herein, we present a case of breast MEC diagnosed at our hospital. The clinicopathologic features were preliminarily discussed by reviewing the literature. A 42-year-old Chinese woman presented with a lump in her right breast that was detected approximately three months prior. A microscopic examination showed that the breast MEC was composed of different proportions of mucinous cells, intermediate cells, and epidermoid cells. Most mucinous cells were positive for cytokeratin 7, while the epidermoid and intermediate cells were positive for p63 and cytokeratin 5/6. All tumor cells were negative for other myoepithelial markers, such as calponin. Tumor cells did not express estrogen, progesterone, or the HER-2/neu protein. After the patient underwent mastectomy, she was diagnosed with a low-grade mucoepidermoid carcinoma based on the clinical, histologic, and immuno-phenotypic characteristics. Our findings provide further insight into the pathologic mechanism of MEC, as correct diagnosis is essential for patient management.

TrkB-Targeted Therapy for Mucoepidermoid Carcinoma

The brain-derived neurotrophic factor (BDNF)/tyrosine receptor kinase B (TrkB) pathway was previously associated with key oncogenic outcomes in a number of adenocarcinomas. The aim of our study was to determine the role of this pathway in mucoepidermoid carcinoma (MEC). Three MEC cell lines (UM-HMC-2, H253 and H292) were exposed to Cisplatin, the TrkB inhibitor, ANA-12 and a combination of these drugs. Ultrastructural changes were assessed through transmission electron microscopy; scratch and Transwell assays were used to assess migration and invasion; and a clonogenic assay and spheroid-forming assay allowed assessment of survival and percentage of cancer stem cells (CSC). Changes in cell ultrastructure demonstrated Cisplatin cytotoxicity, while the effects of ANA-12 were less pronounced. Both drugs, used individually and in combination, delayed MEC cell migration, invasion and survival. ANA-12 significantly reduced the number of CSC, but the Cisplatin effect was greater, almost eliminating this cell population in all MEC cell lines. Interestingly, the spheroid forming capacity recovered, following the combination therapy, as compared to Cisplatin alone. Our studies allowed us to conclude that the TrkB inhibition, efficiently impaired MEC cell migration, invasion and survival in vitro, however, the decrease in CSC number, following the combined treatment of ANA-12 and Cisplatin, was less than that seen with Cisplatin alone; this represents a limiting factor.

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.

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

OBJECTIVES

Primary pulmonary salivary gland-type tumors (PSGT) are rare among all types of lung cancer. The purpose of this study was not only to evaluate the clinical outcomes and prognostic factors after treatment, but also to assess the role for bronchoscopic intervention in PSGT.

METHODS

We analyzed the medical data of 181 PSGT patients who were treated between 1995 and 2018. Patients were divided into three groups according to the initial treatment, as follows: surgical resection with/without adjuvant therapy including bronchoscopic intervention (surgery group, n = 116); bronchoscopic intervention without surgical resection (bronchoscopic intervention group, n = 51); and other treatments group (n = 14). A multivariable Cox proportional hazard regression analysis was used to identify the independent prognostic factors associated with overall survival (OS) and progression free survival (PFS) after the first treatment. In addition, subgroup analysis was performed according to the clinical stage.

RESULTS

Among the 181 patients, 104 (57.5%) patients were diagnosed with adenoid cystic carcinoma (ACC), 71 (39.2%) with mucoepidermoid carcinoma, and 6 (3.3%) with epithelial-myoepithelial carcinoma. In the surgery group, 21 patients underwent bronchoscopic intervention as a bridge therapy before surgery because of respiratory distress. Poor OS was associated with older age, the existence of other malignancy, higher clinical stages, larger tumor size, and non-surgical treatments. Lower PFS was associated with ACC, larger tumor size, and non-surgical treatments. The surgery group had the best OS and PFS among all treatment groups. However, there was no significant difference in the OS between the surgery and bronchoscopic intervention groups (p = 0.66) in patients at high clinical stages.

CONCLUSIONS

Surgical resection was the best initial treatment choice. However, bronchoscopic intervention may be useful as the initial treatment in patients at high clinical stage and as a bridge therapy prior to surgery.

A diagnostic review of carcinomas and sarcomas of the mediastinum: making the diagnosis on fine-needle aspiration and core needle biopsy specimens

The mediastinum is a complex anatomic region that can pose many diagnostic challenges on fine-needle aspiration (FNA) and core needle biopsy (CNB). With the recent technological advancements in EBUS-TBNA and EUS-guided procedures, FNA/CNB is being increasingly utilized to obtain the initial and, in many cases, the only diagnosis. As a result, it is imperative to have an understanding of the pearls and pitfalls associated with both the more common and rarer malignancies that occur at this site. Although the vast majority of mediastinal malignancies encountered in routine clinical practice are metastatic carcinomas to mediastinal lymph nodes, primary tumors and tumors that directly extend into the mediastinum are also encountered. As always, a multimodal approach with clinical and radiographic correlation, a targeted IHC panel, and molecular testing when indicated are indisposable and necessary tools in the diagnostic workup of mediastinal malignancies. This review focuses on the salient diagnostic features of malignancies of epithelial and mesenchymal origin, excluding tumors of neurogenic, thymic, hematolymphoid, and germ cell origins, which are discussed in separate articles of this issue.

Treatment outcomes of patients with tracheobronchial mucoepidermoid carcinoma compared with those with adenoid cystic carcinoma

OBJECTIVE

Tracheobronchial mucoepidermoid carcinoma (TMEC) is an extremely rare salivary gland-type neoplasm. We aimed to explore the clinical characteristics and prognosis of TMEC and to compare them with those of another rare salivary gland-type neoplasm, tracheobronchial adenoid cystic carcinoma (TACC).

METHOD

We performed a retrospective review of all patients pathologically diagnosed with TMEC between 1965 and 2017 at our institution. We reviewed the patients' clinical characteristics, treatment methods and outcomes and compared the results of TMEC and TACC patients.

RESULTS

A total of 115 consecutive patients, including 107 who underwent surgery and 8 who received nonoperative therapy, were included in our study. The 1-, 2-, and 5-year survival rates were 97.89%, 94.17%, and 90.50%, respectively, in the surgical group and 83.33%, 41.67% and 0.00%, respectively, in the nonoperative group. The multivariate analysis showed that N stage was an independent prognostic factor for overall survival (OS). TMEC patients were younger, had a shorter complaint duration, had fewer symptoms, had more bronchial tumors, and were more likely to undergo surgical treatment and achieve an R0 resection (surgically treated patients) than TACC patients; furthermore, TMEC patients had a significantly better OS than TACC patients (P < 0.050).

CONCLUSIONS

TMEC has different characteristics and a better prognosis than TACC, which may reflect the different biological behaviors of these two salivary gland neoplasms. Radical treatment and close follow-up are critical for surgically treated TMEC patients with lymph node metastasis.

Identification of CTNNB1-PLAG1 gene rearrangement in a patient with pulmonary pleomorphic adenoma

Pulmonary pleomorphic adenoma (PA) is a rare salivary gland-type neoplasm, which predominantly occurs in the proximal airway. Rearrangement of the pleomorphic adenoma gene 1 (PLAG1) is the most frequent genetic event in PAs of salivary glands. However, whether pulmonary PA also harbors PLAG1 rearrangement has not been elucidated. Here, we present a case of pulmonary PA, located at the middle lobar bronchus, in a 54-year-old man. CTNNB1-PLAG1 gene fusion was identified by reverse transcription-polymerase chain reaction using formalin-fixed paraffin-embedded tissue (FFPE). Furthermore, immunohistochemical analysis revealed nuclear expression of PLAG1 in all tumor cells. To the best of our knowledge, this is the first reported case of pulmonary PA with CTNNB1-PLAG1 fusion and PLAG1 expression. Our case illustrates the possibility that pulmonary PA could be underpinned by recurrent PLAG1 translocations akin to salivary gland PA.

Mucoepidermoid Carcinoma of the Lacrimal Sac: Clinical-Pathologic Analysis, Including Molecular Genetics

Purpose

The aim of this study was to assess whether mucoepidermoid carcinoma of the lacrimal sac is a counterpart of CRTC1/3-MAML2 gene fusion-related salivary gland mucoepidermoid carcinoma.

Methods

In this retrospective observational case series, pathology records were searched for all cases of lacrimal sac mucoepidermoid carcinoma diagnosed between 1990 and 2018. Data collected included demographics, clinical findings, management, and follow-up. Pathologic parameters assessed included tumor morphology, immunohistochemistry, and MAML2 and EGFR fluorescence in situ hybridization (FISH) studies.

Results

Six patients with mucoepidermoid carcinoma of the lacrimal sac, 5 males and 1 female, with a median age of 63 years (range 24-66) were identified. Five tumors were managed with radical resection and 1 patient underwent orbital exenteration. None of the patients developed recurrence or metastases with an average follow-up of 18 months (range 13-23). All tumors had morphologic and immunohistochemical features of mucoepidermoid carcinoma and overexpressed EGFR. MAML2 FISH was negative for MAML2 rearrangement in all tumors. EGFR FISH demonstrated EGFR amplification in 1 tumor.

Conclusions

Mucoepidermoid carcinoma of the lacrimal sac is not a lacrimal sac counterpart of CRTC1/3-MAML2 gene fusion-related salivary gland mucoepidermoid carcinoma. EGFR pathway activation and EGFR amplification in a subset of these neoplasms suggest the potential role for anti-EGFR agents.

Uncommon Types of Lung Carcinoma With Mixed Histology: Sarcomatoid Carcinoma, Adenosquamous Carcinoma, and Mucoepidermoid Carcinoma

CONTEXT

- Lung tumors are histologically heterogeneous, but classification of lung carcinoma has prognostic impact and increasingly, specific molecular correlates.

OBJECTIVE

- To update the gross, microscopic, and molecular pathology of unusual lung carcinomas to assure accurate classification. In entities with mixed histology, the recognition of specific features or rare patterns is critical to diagnosis. These diagnoses can identify tumors with aggressive clinical behavior, and diagnostic pitfalls can therefore result in underdiagnosis of these already rare entities. Incorrect classification of more indolent tumors into the more aggressive categories can also occur. In the area of molecular pathology, these unusual tumors have a specific spectrum of molecular alterations.

DATA SOURCES

- PubMed searches for lung and sarcomatoid carcinoma, pleomorphic carcinoma, blastoma, carcinosarcoma, and adenosquamous and mucoepidermoid carcinoma were undertaken and this information was integrated with clinical experience of the author.

CONCLUSIONS

- These uncommon carcinomas have specific clinicopathologic features, and attention to their gross and microscopic pathology leads to classification with important associated molecular findings.

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.

Simultaneous evaluation of anti-EGFR-induced tumour and adverse skin effects in a microfluidic human 3D co-culture model

Antibody therapies targeting the epithelial growth factor receptor (EGFR) are being increasingly applied in cancer therapy. However, increased tumour containment correlates proportionally with the severity of well-known adverse events in skin. The prediction of the latter is not currently possible in conventional in vitro systems and limited in existing laboratory animal models. Here we established a repeated dose “safficacy” test assay for the simultaneous generation of safety and efficacy data. Therefore, a commercially available multi-organ chip platform connecting two organ culture compartments was adapted for the microfluidic co-culture of human H292 lung cancer microtissues and human full-thickness skin equivalents. Repeated dose treatment of the anti-EGFR-antibody cetuximab showed an increased pro-apoptotic related gene expression in the tumour microtissues. Simultaneously, proliferative keratinocytes in the basal layer of the skin microtissues were eliminated, demonstrating crucial inhibitory effects on the physiological skin cell turnover. Furthermore, antibody exposure modulated the release of CXCL8 and CXCL10, reflecting the pattern changes seen in antibody-treated patients. The combination of a metastatic tumour environment with a miniaturized healthy organotypic human skin equivalent make this “safficacy” assay an ideal tool for evaluation of the therapeutic index of EGFR inhibitors and other promising oncology candidates.

A rare case of endobronchial mucoepidermoid carcinoma of the lung presenting as non-resolving pneumonia

Background

Mucoepidermoid carcinoma (MEC) is the most common malignant salivary gland tumor, and MECs of the lung are rare, accounting for 0.1–0.2% of malignant lung tumors. Pulmonary MECs are commonly found in the segmental or lobar bronchi, rarely presenting as endobronchial lesions.

Case presentation

Here we describe the case of a 21-year-old female with no comorbid conditions who presented at the emergency room with a cough, yellow phlegm, pleuritic chest pain, and a subjective fever. These symptoms had been present for approximately one week prior to the patient's arrival at the hospital. A chest X-ray revealed right lower lobe alveolar infiltrate and computed tomography of the chest showed dense consolidation of the right lower lobe with ovoid intraluminal density in the right main stem bronchus. Upon fiber optic bronchoscopy, an endobronchial lesion was found in the right main stem sparing the right upper lobe uptake. Endobronchial biopsy results was consistent with MEC of the lung. The patient underwent a bilobectomy with complete resection of the tumor.

Conclusion

Endobronchial MEC is a rare type of salivary gland tumor. Patients with low-grade MECs have a good prognosis, whereas those with high-grade MECs, which are aggressive and associated with metastatic disease, have a poor prognosis. However, early identification and surgical resection can result in a good prognosis.

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.

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.

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.

MUC1 induces acquired chemoresistance by upregulating ABCB1 in EGFR-dependent manner

Chemoresistance contributes to cancer relapse and increased mortality in a variety of cancer types, raising a pressing need to better understand the underlying mechanism. MUC1 is abnormally overexpressed in numerous carcinomas and associated with poor prognosis. However, the functional significance of MUC1 in chemoresistance has not been fully elucidated. Here, we showed that MUC1 expression was considerably induced in cells that had acquired chemoresistance at both transcriptional and post-translational levels. Using gain- and loss-of function approaches, we demonstrated a critical role of MUC1 in induction of drug resistance. Through stimulation of EGFR activation and nuclear translocation, MUC1 increased the expression of ATP-binding cassette transporter B1 (ABCB1). Remarkably, targeted suppression of EGFR or ABCB1 by both shRNAs and inhibitors effectively reversed chemoresistance. Moreover, co-administration of the inhibitors of MUC1-EGFR-ABCB1 with paclitaxel significantly blocked not only tumor growth but also relapse in xenograft mouse model. Our data collectively support a model in which MUC1 induces acquired chemotherapy resistance by upregulating ABCB1 in an EGFR-dependent manner, providing a novel molecular basis of using the EGFR inhibitor in MUC1-positive cancers to prevent chemotherapy resistance.

Surgical outcomes of pulmonary mucoepidermoid carcinoma: A review of 41 cases

INTRODUCTION

Pulmonary mucoepidermoid carcinoma is a rare cancer that occurs primarily in younger patients. The prognostic factors of pulmonary mucoepidermoid carcinoma are largely undetermined, especially in elderly patients. The aim of this study was to examine the clinical characteristics and prognostic factors influencing survival after surgical resection in patients with pulmonary mucoepidermoid carcinoma and also analyze the clinical manifestations and prognostic factors in elderly patients.

MATERIALS AND METHODS

The pathological records of 41 pulmonary mucoepidermoid carcinoma patients (mean age, 61.4 years) who underwent surgical resection at our hospital between January 1991 and July 2015 were retrospectively reviewed. Subjects >65 years of age (n = 22) were considered elderly.

RESULTS

The median follow-up duration was 42.9 (interquartile range, 15.0-120.8) months. Sixteen patients (39.0%) experienced tumor relapse, including 13 patients (81.3%) within 2 years. The 5-year disease-free survival rate was 57.9%. Tumor grade did not influence disease-free survival (P = 0.286). In the multivariate analysis, age, tumor size, pathological T3-4 status, and pathological N2 status were independent predictors of disease-free survival. The 5-year overall survival rate was 57.0%. Tumor grade also did not influence overall survival (P = 0.170). Age, tumor size, pathological T status, and pathological N2 status were independent predictors of overall survival. In elderly patients, the 5-year disease-free survival and overall survival rates were 41.4% and 41.5%, respectively. Pathological T status was the only independent predictor of both disease-free survival and overall survival in elderly patients.

CONCLUSIONS

Prognostic factors identified for pulmonary mucoepidermoid carcinoma in this study differ from those of previous studies. Principally, tumor grade did not influence either disease-free survival or overall survival. Age, tumor size, and pathological factors were independent predictors of disease-free survival and overall survival. In elderly patients, pathological T status was the only independent predictor of disease-free survival and overall survival.

Cytology of Primary Salivary Gland-Type Tumors of the Lower Respiratory Tract: Report of 15 Cases and Review of the Literature

Primary pulmonary salivary gland-type tumors are rare neoplasms arising from the seromucinous submucosal glands of the lower respiratory tract (LRT), the most common of which are mucoepidermoid carcinoma (MEC) and adenoid cystic carcinoma. They are morphologically indistinguishable from their salivary gland counterpart and recognizing them is a challenge, especially on cytological specimens. We analyzed 15 cases of histologically proven primary salivary gland tumors of the LRT to identify cytomorphological features and define potential diagnostic clues that might assist cytopathologists in the preoperative diagnosis of these neoplasias. Three out of the four cases of adenoid cystic carcinomas showed the characteristic tridimensional cell clusters and hyaline globules, whereas the last one did not show malignant cells; only two cases of MEC presented the three characteristic cell types (i.e., squamous, intermediate, and mucin secreting) on cytology. Since these neoplasms are rare and do not have a completely specific set of cytological features, it is important for practicing cytopathologists to be aware of the possibility of encountering them, in specimens from patients with LRT masses, in order to render the correct diagnosis.

[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.