Pulmonary neuroendocrine/carcinoid tumors: a review article

Triple Tumors (Neuroendocrine Tumor, Schwannoma, and Papillary Thyroid Carcinoma) With Brain Lesions in a Single Patient Demonstrating Avidity on 68 Ga-DOTATATE PET/CT and Their Characterization With FDG-PET/CT and Brain MRI

ABSTRACT

Neuroendocrine tumor (NET) typically spreads to the liver, lymph nodes, lungs, and skeleton. Brain metastasis in NET is uncommon. Therefore, each case of detected brain metastases in NET is crucial for the development of treatment guidelines for these types of tumors. We present a unique case of triple tumors (NET, papillary thyroid carcinoma, and schwannoma) in a single patient who presented with neurological symptoms and somatostatin receptor-avid T2 hyperintense multiple metastatic brain lesions from NET on 68 Ga-DOTATATE-PET/CT scan and brain MRI. Despite the rarity of brain metastases in NET, we conclude that the presence of neurological sign or symptoms and/or the detection of somatostatin receptor-avid brain lesions in patients with NET should raise suspicion of brain metastases.

CT-based radiomics for differentiating peripherally located pulmonary sclerosing pneumocytoma from carcinoid

BACKGROUND

Pulmonary sclerosing pneumocytoma (PSP) and pulmonary carcinoid (PC) are difficult to distinguish based on conventional imaging examinations. In recent years, radiomics has been used to discriminate benign from malignant pulmonary lesions. However, the value of radiomics based on computed tomography (CT) images to differentiate PSP from PC has not been well explored.

PURPOSE

We aimed to investigate the feasibility of radiomics in the differentiation between PSP and PC.

METHODS

Fifty-three PSP and fifty-five PC were retrospectively enrolled and then were randomly divided into the training and test sets. Univariate and multivariable logistic analyses were carried to select clinical predictor related to differential diagnosis of PSP and PC. A total of 1316 radiomics features were extracted from the unenhanced CT (UECT) and contrast-enhanced CT (CECT) images, respectively. The minimum redundancy maximum relevance and the least absolute shrinkage and selection operator were used to select the most significant radiomics features to construct radiomics models. The clinical predictor and radiomics features were integrated to develop combined models. Two senior radiologists independently categorized each patient into PSP or PC group based on traditional CT method. The performances of clinical, radiomics, and combined models in differentiating PSP from PC were investigated by the receiver operating characteristic (ROC) curve. The diagnostic performance was also compared between the combined models and radiologists.

RESULTS

In regard to differentiating PSP from PC, the area under the curves (AUCs) of the clinical, radiomics, and combined models were 0.87, 0.96, and 0.99 in the training set UECT, and were 0.87, 0.97, and 0.98 in the training set CECT, respectively. The AUCs of the clinical, radiomics, and combined models were 0.84, 0.92, and 0.97 in the test set UECT, and were 0.84, 0.93, and 0.98 in the test set CECT, respectively. In regard to the differentiation between PSP and PC, the combined model was comparable to the radiomics model, but outperformed the clinical model and the two radiologists, whether in the test set UECT or CECT.

CONCLUSIONS

Radiomics approaches show promise in distinguishing between PSP and PC. Moreover, the integration of clinical predictor (gender) has the potential to enhance the diagnostic performance even further.

Prognostic nomogram and epidemiological analysis for lung atypical carcinoid: A SEER database and external validation study

PURPOSE

Our study aims to delineate the epidemiological distribution of pulmonary carcinoids, including atypical carcinoid (AC) and typical carcinoid (TC), identify independent prognostic factors, develop an integrative nomogram and examine the effects of various surgical modalities on atypical carcinoid-specific survival (ACSS).

METHODS

Joinpoint regression model and age-group distribution diagram were applied to determine the epidemiological trend of the pulmonary carcinoids. Univariate and least absolute shrinkage and selection operator (LASSO)-based Cox regression models were used to identify independent factors, and a nomogram and web-based predictor were developed to evaluate prognosis of AC patients individually. We performed Kaplan-Meier survival analyses to compare the scope of various surgical interventions, with and without G-computation adjustment, utilising restricted mean survival time (RMST) to assess survival disparities.

RESULTS

A total of 1132 patients were recruited from the Surveillance, Epidemiology, and End Results database (SEER) and a separate medical centre in China. The mean age of AC patients was 63.4 years and a smoking history was identified in 79.8% of AC patients. Joinpoint analysis shows rising annual rates of new AC and carcinoid cases among lung cancers. Both the proportion of pulmonary TC and AC within the total lung cancer population exhibits an L-shaped trend across successive age groups. The nomogram predicted 1, 3 and 5 years of AC with excellent accuracy and discrimination. Kaplan-Meier survival analyses, conducted both pre- and post-adjustment, demonstrated that sublobar resection's survival outcomes were not inferior to those of lobectomy in patients with stage I-II and stage III disease.

CONCLUSION

This study is the first to reveal epidemiological trends in pulmonary carcinoids over the past decade and across various age cohorts. For patients with early-stage AC, sublobar resection may be a viable surgical recommendation. The established nomogram and web-based calculator demonstrated decent accuracy and practicality.

Skin and Subcutaneous Tissue Metastases of the Pulmonary Carcinoid Tumor on 68 Ga-DOTATATE PET/CT

ABSTRACT

Pulmonary carcinoid tumors are a very rare type of neuroendocrine tumor, accounting for only 1% to 2% of all primary lung cancers. Pulmonary carcinoids most commonly metastasize to the mediastinal lymph nodes, liver, and bones. Metastasis of pulmonary carcinoids to the skin and subcutaneous tissue is extremely rare and has been reported in only a small number of cases. We presented 68 Ga-DOTATATE PET/CT findings of an exceptional case of a pulmonary carcinoid tumor with extensive skin, subcutaneous, thyroid, and intramuscular metastases.

Imaging of lung cancer

Lung cancer is the leading cause of cancer-related mortality globally. Imaging is essential in the screening, diagnosis, staging, response assessment, and surveillance of patients with lung cancer. Subtypes of lung cancer can have distinguishing imaging appearances. The most frequently used imaging modalities include chest radiography, computed tomography, magnetic resonance imaging, and positron emission tomography. Artificial intelligence algorithms and radiomics are emerging technologies with potential applications in lung cancer imaging.

Clinical activity of pembrolizumab with or without chemotherapy in advanced pulmonary large-cell and large-cell neuroendocrine carcinomas: a multicenter retrospective cohort study

BACKGROUND

Immune checkpoint inhibitors (ICI)-based combination strategies have improved the survival outcomes in advanced non-small cell lung cancers; however, data regarding their efficacy remains limited for uncommon histological types, including large-cell carcinoma (LCC) and large-cell neuroendocrine carcinoma (LCNEC).

METHODS

We retrospectively analyzed a total of 60 patients with advanced LCC and LCNEC - 37 treatment-naïve and 23 pre-treated - who received pembrolizumab with or without chemotherapy. Treatment and survival outcomes were analyzed.

RESULTS

Of the 37 treatment-naïve patients who received first-line pembrolizumab combined with chemotherapy, the 27 patients with LCC had an overall response rate (ORR) of 44.4% (12/27) and a disease control rate (DCR) of 88.9% (24/27); whereas 10 patients with LCNEC had an ORR of 70% (7/10) and DCR of 90% (9/10). The median progression-free survival (mPFS) was 7.0 months (95% confidence intervals [CI]: 2.2-11.8) and median overall survival (mOS) was 24.0 months (95%CI: 0.0-50.1) for first-line pembrolizumab plus chemotherapy of LCC (n = 27), whereas mPFS was 5.5 months (95%CI: 2.3-8.7) and mOS was 13.0 months (95%CI: 11.0-15.0) for first-line pembrolizumab plus chemotherapy of LCNEC (n = 10). Of the 23 pre-treated patients who received subsequent-line pembrolizumab with or without chemotherapy, mPFS was 2.0 months (95% CI: 0.6-3.4) and mOS was 4.5 months (95% CI: 0.0-9.0) for LCC and mPFS was 3.8 months (95% CI: 0.0-7.6) and mOS was not reached for LCNEC.

CONCLUSION

Our study provides real-world clinical evidence of the anti-tumor activity of pembrolizumab plus chemotherapy in advanced LCC and LCNEC, indicating that this regimen could serve as a treatment option, particularly as first-line therapy, for improving the survival outcomes of patients with these rare histological subtypes of lung cancer.

TRIAL REGISTRATION

NCT05023837(ESPORTA, 27/08/2021).

Current Management of Carcinoid Tumor

Bronchopulmonary carcinoid tumors are rare, well-differentiated neuroendocrine neoplasms. They can be categorized as typical or atypical lesions and are low-to-intermediate-grade, respectively. The cornerstone of therapy for carcinoid tumors is surgical resection and current consensus guidelines recommend anatomic resection for stage I to IIIA disease. The renewed interest in sublobar resections for the treatment of lung malignancies has sparked debate over the degree of resection necessary for these indolent lesions. Segmentectomy provides an oncologic resection while preserving as much lung parenchyma as possible, and is a reasonable approach to apply to small, undifferentiated, or typical carcinoid lesions.

Prognostic factors for pulmonary carcinoid with positive lymph node after surgical resection: a SEER database study

BACKGROUND

Prognostic factors and role with chemotherapy (CT) and radiotherapy (RT) remain unclear for patients of pulmonary carcinoid (PC) with positive lymph node after surgery.

METHODS

PC patients who underwent surgery and with positive lymph node between 2000 and 2016 were identified from the SEER database. Univariate and multivariate cox regression analysis were used to identify independent risk factors for overall survival (OS).

RESULTS

A total of 552 patients were identified. Multivariate analysis indicated that age (≤ 70/ > 70) (HR = 0.32, 95% CI 0.21-0.50; P < 0.001), histologic type (typical carcinoid [TC]/atypical carcinoid [AC]) (HR = 0.53, 95% CI 0.36-0.78, P = 0.001), number of positive lymph nodes (n ≥ 3/n = 1-2) (HR = 1.91, 95% CI 1.26-2.90; P = 0.002), and treatment mode (surgery + RT/surgery alone) (HR = 1.75, 95% CI 1.09-2.81; P 0.02) were independent prognostic factors for OS. In subgroup analysis according to histological type, prognostic factors were similar between AC and TC, except surgery + RT being negative prognostic factor for TC but AC. No significant difference in OS was observed between the surgery alone and surgery + CT in any subgroup of patients.

CONCLUSIONS

Age > 70, histological type of AC, positive lymph nodes ≥ 3, and surgery + RT were likely to be negative prognostic factors for OS. Addition CT to surgery did not appear to provide additional OS benefit.

Survival Benefit of Adjuvant Chemotherapy in Pulmonary Carcinoid Tumors

Pulmonary carcinoid tumors are a rare subtype of neuroendocrine cell tumor found in approximately 1–2% of lung cancers. Management is primarily through surgical resection, with limited benefit of adjuvant therapy in the clinical setting. Genomic profiling is in the nascent stages to molecularly classify these tumors, but there are promising insights for future targeted therapy. A total of 80 abstracts were analyzed for further review with 11 included in our final analysis. Only 4 of the 11 reviewed in depth provided statistical analysis. We evaluated PFS, OS, 1- and 5-year survival as mentioned in the studies. Nodal and KI67 status were also analyzed. Based on the current literature, there is no definitive evidence that adjuvant chemotherapy after resection confers a survival benefit in typical or atypical carcinoids.

A qualitative study to understand the experience of somatostatin analog treatments from the perspective of patients with neuroendocrine tumors

Purpose

Neuroendocrine tumors (NETs) negatively impact patients’ quality of life. Octreotide long-acting release (LAR) and lanreotide depot are somatostatin analogs (SSAs) approved to treat NETs. The study objective was to explore SSA treatment experiences and preferences of patients with NETs.

Methods

Qualitative interviews were conducted in US adults (≥ 21 years) with NETs who had ≥ 6 months’ treatment with each SSA and transitioned from octreotide LAR to lanreotide depot within the previous year. Participants were asked open-ended questions about their experiences with octreotide LAR and lanreotide depot, treatment preferences, and SSA treatment attributes.

Results

Twenty participants (mean age: 58 years; 90% female; 85% white) completed interviews. The most common reasons for treatment transition were doctor recommendation (70%), treatment not working as expected (55%), and injection type preference (45%). Participants reported 34 unique favorable attributes of SSA treatment and 82 unique unfavorable attributes. Symptom control was the most frequently reported favorable attribute (associated with octreotide LAR by 60% of participants and lanreotide depot by 65%). Painful injection (65%) was most frequently cited unfavorable attribute for octreotide LAR and injection experience dependent on administrator (35%) for lanreotide depot. The three SSA treatment attributes rated as most important were side effects, symptom control, and ability to stabilize tumor.

Conclusion

Our qualitative data provide valuable insight into the treatment attributes that patients with NETs consider important when making SSA treatment decisions. Factors related to injection administration, side effects, and symptom control are important to patients and should be included in patient-provider communications in clinical contexts.

Supplementary Information

The online version contains supplementary material available at 10.1007/s00520-022-07054-x.

Bronchial Carcinoids: From Molecular Background to Treatment Approach

Simple Summary

Bronchial carcinoids (BCs) are uncommon and usually slow growing neuroendocrine epithelial malignancies that represent less than 2% of all lung cancers. Differences in the extent of molecular alterations between neuroendocrine carcinomas and BCs may underline the differences in the aggressiveness of these lesions. Moreover, although atypical BCs and typical BCs have similar set of mutations, some differential molecular and genetic alterations have been described between these two entities. A better understanding of the genetic and molecular background of BCs would allow a better selection of medical treatments in these patients. Regarding treatment, most BCs can be cured by surgery; however, inoperable tumors are mostly insensitive to chemotherapy and radiotherapy. In advanced BCs, the only drug that has a positive phase III clinical trial in BCs is everolimus. Somatostatin analogues constitute the gold standard for symptomatic relief. Peptide receptor radionuclide therapy has been associated with longer progression free. The efficacy of other treatments such as antiangiogenic agents and immunotherapy is still not established.

Abstract

A better understanding of the genetic and molecular background of bronchial carcinoids (BCs) would allow a better estimation of the risk of disease progression and the personalization of treatment in cases of advanced disease. Molecular studies confirmed that lungs neuroendocrine tumors (NETs) and neuroendocrine carcinomas (NECs) are different entities; thus, no progression of NET to NEC is expected. In BCs, MEN1 gene mutations and deletions and decreased gene expression have been associated with a poor prognosis. ATRX mutation has also been linked to a shorter disease-specific survival. In terms of therapeutic targets, PI3K/AKT/mTOR pathway mutations have been described in 13% of typical carcinoids (TCs) and 39% of atypical carcinoids (ACs), representing a targetable mutation with kinase inhibitors. Regarding treatment, surgical resection is usually curative in localized BCs and adjuvant treatment is not routinely recommended. Multiple options for systemic therapy exist for patients with advanced BCs, although limited by a heterogeneity in the scientific evidence behind their use recommendation. These options include somatostatin analogues, everolimus, peptide receptor radionuclide therapy, chemotherapy, radiotherapy, antiangiogenic agents, and immunotherapy. In this article, we provide a comprehensive review about the molecular and genetic background of BCs, and about the treatment of local and metastatic disease, as well as the main paraneoplastic syndromes that have been associated with this tumor.

The Impact of Extended Delayed Surgery for Indolent Lung Cancer or Part-solid Ground Glass Nodules

BACKGROUND

During the COVID-19 pandemic, patients with lung cancer may experience treatment delays. The objective of this study was to evaluate the impact of extended treatment delays on survival among patients with stage I typical bronchopulmonary carcinoid (BC), lepidic predominant adenocarcinoma (LPA) or invasive adenocarcinoma with a lepidic component (ADL).

METHODS

Using National Cancer Data Base data (2004-2015), multivariable Cox regression analysis with penalized smoothing splines was performed to examine the association between treatment delay and all-cause mortality for stage I BC, LPA and ADL. Propensity score-matched analyses compared the overall survival in patients who received "early" versus "delayed" surgery (i.e. 0-30 versus 90-120 days following diagnosis) across the different histologic subtypes.

RESULTS

During the study period, patients with stage I BC (n=4,947), LPA (n=5,340) and ADL (n=6,816) underwent surgery. Cox regression analysis of these cohorts showed a gradual steady increase in the hazard ratio the longer treatment is delayed. However, in propensity score-matched analyses which created cohorts of patients who underwent early and delayed surgery that were well-balanced in patient characteristics, no significant differences in 5-year survival were found between early and delayed surgery for stage I BC (87% [95% CI:77-93] vs 89% [95% CI:80-94]), stage I LPA (73% [95% CI:64-80] vs 77% [95% CI:68-83]) and stage I ADL (71% [95% CI:64-76] vs 69% [95% CI:60-76]).

CONCLUSIONS

During the COVID-19 pandemic, for early-stage indolent lung tumors and part-solid ground glass lung nodules, a delay of surgery by 3-4 months following diagnosis can be considered.

Immune-Checkpoint Inhibitors in Advanced Non-Small Cell Lung Cancer With Uncommon Histology

BACKGROUND

Immune-checkpoint inhibitors (ICIs) have significantly improved outcome of advanced non-small cell lung cancer (aNSCLC) patients. However, their efficacy remains uncertain in uncommon histologies (UH).

MATERIALS AND METHODS

Data from ICI treated aNSCLC patients (April,2013-January,2021) in one Institution were retrospectively collected. Univariate and multivariate survival analyses were estimated by Kaplan-Meier and Cox proportional hazards regression model, respectively. Objective response rate (ORR) and disease control rate (DCR) were assessed.

RESULTS

Of 375 patients, 79 (21.1%) had UH: 19 (24.1%) sarcomatoid carcinoma, 15 (19.0%) mucinous adenocarcinoma, 10 (12.6%) enteric adenocarcinoma, 8 (10.1%) adenocarcinoma not otherwise specified, 7 (8.9%) large-cell neuroendocrine carcinoma, 6 (7.6%) mixed histology non-adenosquamous, 5 (6.3%) adenosquamous carcinoma, 9 (11.4%) other UH. In UH group, programmed death-ligand 1 (PD-L1) <1%, 1-49%, ≥50% and unknown expression were reported in 27.8%, 22.8%, 31.7% and 17.7% patients respectively and ICI was the second/further-line in the majority of patients. After a median follow-up of 35.64 months (m), median progression-free survival (mPFS) was 2.5 m in UH [95% CI 2.2-2.9 m] versus (vs.) 2.7 m in CH [95% CI 2.3-3.2 m, P-value = .584]; median overall survival (mOS) was 8.8 m [95% CI 4.9-12.6 m] vs. 9.7 m [95% CI 8.0-11.3 m, P-value = .653]. At multivariate analyses only ECOG PS was a confirmed prognostic factor in UH. ORR and DCR were 25.3% and 40.5% in UH vs. 21.6% and 49.5% in CH [P-value = .493 and .155 respectively].

CONCLUSIONS

No significant differences were detected between UH and CH groups. Prospective trials are needed to understand ICIs role in UH population.

Incidence and Survival Outcomes in Patients with Lung Neuroendocrine Neoplasms in the United States

BACKGROUND

The incidence and prevalence of neuroendocrine neoplasms (NENs) are rapidly rising. Epidemiologic trends have been reported for common NENs, but specific data for lung NENs are lacking.

METHODS

We conducted a retrospective analysis utilizing the Surveillance, Epidemiology, and End Results (SEER) database. Associated population data were utilized to report the annual age-adjusted incidence and overall survival (OS) trends. Trends for large-cell neuroendocrine carcinoma (LCNEC) and atypical carcinoid (AC) were reported from 2000-2015, while those for typical carcinoid (TC) and small cell lung cancer (SCLC) were reported from 1988-2015.

RESULTS

We examined a total of 124,969 lung NENs [103,890-SCLC; 3303-LCNEC; 8146-TC; 656-AC; 8974-Other]. The age-adjusted incidence rate revealed a decline in SCLC from 8.6 in 1988 to 5.3 in 2015 per 100,000; while other NENs showed an increase: TC increased from 0.57 in 1988 to 0.77 in 2015, AC increased from 0.17 in 2001 to 0.22 in 2015, and LCNEC increased from 0.16 in 2000 to 0.41 in 2015. The 5-year OS rate among SCLC, LCNEC, AC, and TC patients was 5%, 17%, 64%, and 84%, respectively. On multivariable analyses, OS and disease-specific survival (DSS) varied significantly by stage, sex, histological type, insurance type, marital status, and race, with a better survival noted in earlier stages, females, married, insured, Hispanic and other races, and urban population. Similarly, TC and AC had better survival compared to SCLC and LCNEC.

CONCLUSION

The incidence of lung NENs is rising, possibly in part because of advanced radiological techniques. However, the incidence of SCLCs is waning, likely because of declining smoking habits. Such population-based studies are essential for resource allocation and to prioritize future research directions.

Effectiveness of Thermal Ablation and Stereotactic Radiotherapy Based on Stage I Lung Cancer Histology

PURPOSE

To assess whether the effectiveness of thermal ablation (TA) and stereotactic body radiotherapy (SBRT) as initial treatments for stage I lung cancer varies depending on the histological subtype.

MATERIALS AND METHODS

The 2004-2016 National Cancer Database was queried for patients with American Joint Committee on Cancer stage I lung cancer treated with TA or SBRT. Patients <18 years, those treated with surgery or chemotherapy, or those with unknown survival and follow-up were excluded. TA and SBRT patients were 1:5 propensity score matched separately for each histological subtype to adjust for confounders. Overall survival (OS) was assessed using Cox models.

RESULTS

A total of 28,425 patients were included (SBRT, n = 27,478; TA, n = 947). TA was more likely to be used in Caucasian patients, those with more comorbidities and smaller neuroendocrine tumors (NETs) of the lower lobe, and those whose treatment had taken place in the northeastern United States. After propensity score matching, a cohort with 4,085 SBRT and 817 TA patients with balanced confounders was obtained. In this cohort, OS for TA and SBRT was comparable (hazard ratio = 1.07; 95% confidence interval,0.98-1.18; P = .13), although it varied by histological subtypes: higher OS for TA was observed in patients with non-small cell NETs (vs SBRT hazard ratio = 0.48; 95% confidence interval, 0.24-0.95; P = .04). No significant OS differences between TA and SBRT were noted for adenocarcinomas, squamous cell carcinomas, small cell carcinomas, and non-neuroendocrine large cell carcinomas (each, P > .1).

CONCLUSIONS

OS following TA and SBRT for stage I lung cancer is comparable for most histological subtypes, except that OS is longer after TA in non-small cell NETs.

Bronchoscopic diagnosis and treatment of endobronchial carcinoid: case report and review of the literature

Carcinoid tumours are rare neuroendocrine neoplasms that mostly occur in younger adults with low tendencies to metastasise. Based on their histological characteristics, they are divided into typical and atypical subtypes. The most common presenting symptoms are due to central airway obstruction. The first step in the diagnostic assessment should be a computed tomography (CT) scan, as it provides information both for local tumour extent and lymph node involvement. Bronchoscopy is the main tool for histological confirmation, evaluation of bronchial wall invasion and removal of endobronchial manifestation with subsequent resolution of atelectasis. Endobronchial ultrasound may be necessary to rule out lymph node metastasis. Somatostatin receptor scintigraphy in combination with CT can rule out further metastatic disease.Surgical resection using parenchyma-sparing techniques remains the gold standard for treatment. For selected patients, endobronchial therapy could be an alternative for minimal invasiveness. Long-term follow-up is suggested due to the high likelihood of recurrence.Here, we describe our clinical experience in a 35-year-old male patient who originally presented with haemoptysis and a central polypoid tumour in the left main bronchus revealed by a CT scan. The histological characteristics were indicative of a typical carcinoid. The patient was treated using an endobronchial approach only. No complications and no recurrences have been observed in a follow-up of 2 years.

Clinicopathological and immunohistochemical study of pulmonary neuroendocrine tumors - A single-institute experience

INTRODUCTION

Pulmonary neuroendocrine tumors (NETs) comprise a spectrum of tumors ranging from indolent to highly aggressive neoplasm. This study aims to study the clinicopathological and immunohistochemical features of NETs and assess the sensitivity of various IHC markers.

MATERIALS AND METHODS

All consecutive cases of pulmonary NETs diagnosed from January 2016 to June 2019 were analyzed retrospectively. The routine hematoxylin- and eosin-stained sections along with immunohistochemistry (IHC) slides were reviewed. IHC was done using a panel of markers which included synaptophysin, chromogranin, CD56, thyroid transcription factor-1 (TTF-1), p-40, napsin-A, and ki67.

RESULTS

Of total number of 53 patients, diagnosis was made on biopsy in 40 patients and resection specimen in 13 patients. Small cell lung carcinoma was the most common (31 cases), followed by 16 cases of typical carcinoid, 5 cases of atypical carcinoid, and 1 case of combined SCLC. Both synaptophysin and chromogranin were positive in all the cases of typical carcinoid. Synaptophysin had better sensitivity than chromogranin in atypical carcinoid and small cell carcinoma. CD56 was positive in 8 out of 9 cases done. TTF-1 was negative in all the cases of typical carcinoid. The sensitivity of TTF-1 in small cell carcinoma was 85.19%. The mean Ki67 labeling index was 1.4%, 6.6%, and 65.6% in typical, atypical carcinoid, and small cell carcinomas, respectively.

CONCLUSION

Synaptophysin was more sensitive than chromogranin, especially in atypical carcinoid and small cell carcinoma. TTF-1 along with high Ki67 differentiates small cell carcinoma from carcinoid.

Clinical profile and treatment outcomes of metastatic neuroendocrine carcinoma: A single institution experience

Background:

Neuroendocrine carcinoma (NEC) is a rare tumor arising from the diffuse neuroendocrine system. Most of these present in the advanced stage and palliative chemotherapy remains the only option. The prognosis remains poor with the standard chemotherapy regimen of platinum and etoposide (EP) providing modest survival benefit.

Methods:

The study was done for 3 years at a tertiary cancer center in South India. Patients with a diagnosis of metastatic NEC were analyzed for clinical and pathological characteristics. The treatment outcomes and prognostic factors were evaluated using appropriate statistical test.

Results:

A total of 114 patients of metastatic NEC satisfied the inclusion criteria and were analyzed. Gastrointestinal including hepatobiliary tract (33%) was the most common site of primary disease followed by lung (26%), genitourinary (15%), head and neck (14%), and unknown primary (9%). On analysis of pattern of metastasis, liver (65%) was the most common site followed by bone (54%) and lung (42%). The median overall survival was 11 months with a statistically significant difference between pulmonary and extrapulmonary disease (8 vs. 13 months; P = 0.003). Ki67% value was strongly associated with prognosis (hazard ratio 0.517, 95% confidence interval; 0.318–0.840, P = 0.008) whereas age, sex, and lactate dehydrogenase level did not show any relation with survival.

Conclusion:

The outcome of advanced NEC with standard chemotherapy remains poor. Larger studies with other therapeutic and novel agents are warranted to improve the treatment outcomes.

A National Study of Surgically Managed Atypical Pulmonary Carcinoid Tumors

BACKGROUND

Atypical pulmonary carcinoid tumors represent a subset of non-small cell lung cancer; however, their relative infrequency has left prognosis, management and long-term survival associated with atypical carcinoids, incompletely characterized.

METHODS

Patients aged 18 years or more diagnosed with atypical or typical pulmonary carcinoid between 2010 and 2015 within the National Cancer Database were evaluated. Survival was measured using Kaplan-Meier survival and multivariable Cox proportional hazards regression, adjusting for patient and tumor attributes.

RESULTS

A total of 816 atypical and 5688 typical carcinoid patients were identified in the cohort. Patients with atypical carcinoids tended to be older, have larger tumors, and later stage disease. The unadjusted overall 5-year survival for atypical carcinoid patients was 84%, 74%, 52%, and 51% for stages I, II, III, and IV, respectively. The unadjusted 5-year survival for typical carcinoids was 93%, 93%, 89%, and 87% for stages I, II, III, and IV, respectively. Nodal upstaging (ie, lymph node metastases identified in surgical specimens of clinically staged N0 patients) was seen in 16% of atypical and 7% of typical carcinoid patients. Increasing age, comorbidities, and stage were identified as significant predictors of mortality for atypical patients in multivariable analysis. Extent of surgical resection (lobectomy vs sublobar) was not identified as a predictor of survival for atypical carcinoid.

CONCLUSIONS

Atypical carcinoid tumors represent a distinct subset of carcinoid tumors, with a tendency toward more aggressive behavior. Further study of the optimal surgical management is warranted.

Long Non-coding RNAs in Pulmonary Neuroendocrine Neoplasms

Pulmonary neuroendocrine neoplasms (NENs) are classified into low-grade neuroendocrine tumors and high-grade neuroendocrine carcinomas (NECs). There are significant differences in therapeutic strategies of the different NEN subtypes, and therefore, precise classification of pulmonary NENs is critical. However, challenges in pulmonary NEN classification include overlap of diagnostic histological features among the subtypes and reduced or negative expression of neuroendocrine markers in poorly differentiated pulmonary NECs. Recently, transcription factor insulinoma-associated protein 1 (INSM1) was identified as a sensitive marker of neuroendocrine and neuroepithelial differentiation. In this study, INSM1 expression was detected by immunohistochemistry in greater than 94% of pulmonary NENs, indicating that it is a highly sensitive marker of pulmonary NENs and is useful to detect poorly differentiated pulmonary NECs. Although there are well-established morphological and immunohistologic criteria to diagnose pulmonary NENs, there is no universal consensus regarding prognostic markers of pulmonary NENs. Studies have shown that non-small cell lung cancers express long non-coding RNAs (lncRNAs), which regulate gene expression, epithelial-to-mesenchymal transition, and carcinogenesis. We characterized expression and function of lncRNAs, including HOX transcript antisense RNA (HOTAIR), maternally expressed 3 (MEG3), and prostate cancer antigen 3 (PCA3) in pulmonary NENs, including typical carcinoid tumors, atypical carcinoid tumors, small cell lung carcinoma (SCLC/NEC), and large cell neuroendocrine carcinoma (LCNEC/NEC). In situ hybridization and real-time polymerase chain reaction studies showed higher expression (p < 0.01) of all lncRNAs in SCLC/NEC. Small interfering RNA studies indicated a role for MEG3 and PCA3 in tumor proliferation. Therefore, these lncRNAs may serve as prognostic indicators of pulmonary NEN aggressiveness and as possible therapeutic targets.

Multiple liver metastases of pulmonary carcinoid successfully treated by two-stage hepatectomy combined with embolization of portal vein branches: Report of a case

•

The prognosis of atypical pulmonary carcinoid with liver metastases is poor, and the patients are often treated using non-surgical therapies.

•

We successfully treated multiple liver metastases from atypical pulmonary carcinoid by using two-stage hepatectomy combined with embolization of portal vein branches.

•

Two-stage hepatectomy may be a good option for bilobar multiple liver metastases of atypical pulmonary carcinoid.

Introduction

The prognosis of atypical pulmonary carcinoid with liver metastases is extremely poor, and patients with multiple liver metastases are often treated using non-surgical therapies. We report a case with multiple liver metastases from atypical pulmonary carcinoid that was successfully treated using two-stage hepatectomy combined with embolization of portal vein branches.

Presentation of case

A 48-year-old man was referred to our department after multiple liver tumors were detected in both liver lobes on computed tomography. He had undergone right upper lobectomy of the lung for atypical pulmonary carcinoid (T2a, N0, M0; Stage IB) 2 years previously. Positron emission tomography-computed tomography showed no extrahepatic tumor manifestations. The tumors were located in segment 2, 3, 5/8 and the right hepatic vein drainage area. We planned complete resection of metastases in a two-stage hepatectomy. The first stage comprised concomitant left lateral segmentectomy, partial hepatectomy of segment 5/8 and portal vein embolization of the posterior segmental branches. The second stage comprised resection of the right hepatic vein drainage area, performed 21 days after the first surgery. Histopathological diagnosis was liver metastases of atypical pulmonary carcinoid. Postoperative bile leak developed, which was treated with endoscopic retrograde biliary drainage and percutaneous bile leak drainage. He has been followed for 24 months postoperatively without tumor recurrence.

Discussion

Two-stage hepatectomy may represent an option for bilobar multiple liver metastases from atypical pulmonary carcinoid.

Conclusion

We successfully treated a patient with multiple liver metastases of atypical pulmonary carcinoid using a two-stage hepatectomy combined with portal vein embolization of the posterior segmental branches.

Whole-exome and RNA sequencing of pulmonary carcinoid reveals chromosomal rearrangements associated with recurrence

INTRODUCTION

The majority of pulmonary carcinoid (PC) tumors can be cured by surgical resection alone, but a significant proportion of patients experience recurrence. As PC is insensitive to conventional chemotherapy, further clarification of the molecular mechanisms of metastasis is needed in order to develop targeted therapeutics.

METHODS

We performed comprehensive whole-exome sequencing (WES) of primary tumors and corresponding normal lung tissues from 14 PC patients (including 4 patients who developed postsurgical distant metastasis) and RNA sequencing of primary tumors from 6 PC patients (including 4 patients who developed postsurgical distant metastasis). Exon array-based gene expression analysis was performed in 25 cases of PC.

RESULTS

We identified a total of 139 alterations in 136 genes. MUC6 and SPTA1 were recurrently mutated at a frequency of 21% (3/14) and 14% (2/14), respectively. Mucin protein family genes including MUC2, MUC4 and MUC6 were mutated in a mutually exclusive manner in 36% (5/14). Pathway analysis of the mutated genes revealed enrichment of genes involved in mitogen-activated protein kinase (MAPK) signaling, regulation of the actin cytoskeleton and focal adhesion, and transforming growth factor (TGF)-β signaling. RNA sequencing revealed a total of 8 novel fusion transcripts including one derived from a chromosomal translocation between the TRIB2 and PRKCE genes. All of the 8 fusion genes were detected in primary PCs that had developed metastasis after surgical resection. We identified 14 genes (DENND1B, GRID1, CLMN, DENND1B, NRP1, SEL1L3, C5orf13, TNFRSF21, TES, STK39, MTHFD2, OPN3, MET, and HIST1H3C) up-regulated in 5 PCs that had relapsed after surgical resection.

CONCLUSIONS

In this study we identified novel somatic mutations and chromosomal rearrangements in PC by examining clinically aggressive cases that had developed postsurgical metastasis. It will be essential to validate the clinical significance of these genetic changes in a larger independent patient cohort.

Clinicopathological characteristics and genetic analysis of pulmonary carcinoid tumors: A single-center retrospective cohort study and literature review

Pulmonary carcinoid tumors, including typical and atypical carcinoids, are well-differentiated neuroendocrine tumors (NETs) that represent 1–2% of all lung cancer cases. In the present study, all cases of well-differentiated NETs diagnosed at Tianjin Medical University General Hospital (Tianjin, China) between 2006 and 2016 were reviewed, and 20 pulmonary carcinoid cases were identified. The clinical features of these cases were summarized, and the results of pathological and imaging examinations were collated. As a low-grade malignant pulmonary neoplasm, the molecular biological mechanism of pulmonary carcinoids is yet to be elucidated. To investigate the underlying molecular mechanisms behind pulmonary carcinoids and to determine an effective molecular targeted therapeutic strategy, next-generation sequencing (NGS) was performed using tissue samples from six patients to determine additional molecular biological characteristics that may help guide targeted therapy. A total of 27 somatic mutations in 21 genes were detected. Of note, mutations in the KIT proto-oncogene receptor tyrosine kinase, Erb-B2 receptor tyrosine kinase 4, MET proto-oncogene receptor tyrosine kinase and insulin-like growth factor 1 genes occurred in two out of six cases. Since treatments for advanced carcinoids are relatively ineffective, molecular profiling may contribute to the identification of novel treatments. In addition, the literature on mutations in pulmonary carcinoids was reviewed and available clinical information and features of this tumor type were summarized.

Epithelial cell plasticity defines heterogeneity in lung cancer

Lung cancer is the leading cause of cancer death for both men and women and accounts for almost 18.4% of all deaths due to cancer worldwide, with the global incidence increasing by approximately 0.5% per year. Lung cancer is regarded as a devastating type of cancer owing to its high prevalence, reduction in the health-related quality of life, frequently delayed diagnosis, low response rate, high toxicity, and resistance to available therapeutic options. The highly heterogeneous nature of this cancer with a proximal-to-distal distribution throughout the respiratory tract dramatically affects its diagnostic and therapeutic management. The diverse composition and plasticity of lung epithelial cells across the respiratory tract are regarded as significant factors underlying lung cancer heterogeneity. Therefore, definitions of the cells of origin for different types of lung cancer are urgently needed to understand lung cancer biology and to achieve early diagnosis and develop cell-targeted therapies. In the present review, we will discuss the current understanding of the cellular and molecular alterations in distinct lung epithelial cells that result in each type of lung cancer.

Progesterone receptor isoform B expression in pulmonary neuroendocrine cells decreases cell proliferation

The progesterone receptor (PR) has been reported to play important roles in lung development and function, such as alveolarization, alveolar fluid clearance (AFC) and upper airway dilator muscle activity. In the lung, pulmonary neuroendocrine cells (PNECs) are important in the etiology and progression of lung neuroendocrine tumors (NETs). Women with lung NETs had significantly better survival rates than men, suggesting that sex steroids and their receptors, such as the PR, could be involved in the progression of lung NETs. The PR exists as two major isoforms, PRA and PRB. How the expression of different PR isoforms affects proliferation and the development of lung NETs is not well understood. To determine the role of the PR isoforms in PNECs, we constructed H727 lung NET cell models expressing PRB, PRA, Green Fluorescence Protein (GFP) (control). The expression of PRB significantly inhibited H727 cell proliferation better than that of PRA in the absence of progestin. The expression of the unrelated protein, GFP, had little to no effect on H727 cell proliferation. To better understand the role of the PR isoform in PNECs, we examined PR isoform expression in PNECs in lung tissues. A monoclonal antibody specific to the N-terminus of PRB (250H11 mAb) was developed to specifically recognize PRB, while a monoclonal antibody specific to a common N-terminus epitope present in both PRA and PRB (1294 mAb) was used to detect both PRA and PRB. Using these PR and PRB-specific antibodies, we demonstrated that PR (PRA&PRB) and PRB were expressed in the PNECs of the normal fetal and adult lung, with significantly higher PR expression in the fetal lung. Interestingly, PRB expression in the normal lung was associated with lower cell proliferation than PR expression, suggesting a distinct role of PRB in the PNECs. A better understanding of the molecular mechanism of PR and PR isoform signaling in lung NET cells may help in developing novel therapeutic strategies that will benefit lung NET patients in the future.

Low-dose computed tomography for lung cancer screening in high-risk populations: a systematic review and economic evaluation

BACKGROUND

Diagnosis of lung cancer frequently occurs in its later stages. Low-dose computed tomography (LDCT) could detect lung cancer early.

OBJECTIVES

To estimate the clinical effectiveness and cost-effectiveness of LDCT lung cancer screening in high-risk populations.

DATA SOURCES

Bibliographic sources included MEDLINE, EMBASE, Web of Science and The Cochrane Library.

METHODS

Clinical effectiveness - a systematic review of randomised controlled trials (RCTs) comparing LDCT screening programmes with usual care (no screening) or other imaging screening programmes [such as chest X-ray (CXR)] was conducted. Bibliographic sources included MEDLINE, EMBASE, Web of Science and The Cochrane Library. Meta-analyses, including network meta-analyses, were performed. Cost-effectiveness - an independent economic model employing discrete event simulation and using a natural history model calibrated to results from a large RCT was developed. There were 12 different population eligibility criteria and four intervention frequencies [(1) single screen, (2) triple screen, (3) annual screening and (4) biennial screening] and a no-screening control arm.

RESULTS

Clinical effectiveness - 12 RCTs were included, four of which currently contribute evidence on mortality. Meta-analysis of these demonstrated that LDCT, with ≤ 9.80 years of follow-up, was associated with a non-statistically significant decrease in lung cancer mortality (pooled relative risk 0.94, 95% confidence interval 0.74 to 1.19). The findings also showed that LDCT screening demonstrated a non-statistically significant increase in all-cause mortality. Given the considerable heterogeneity detected between studies for both outcomes, the results should be treated with caution. Network meta-analysis, including six RCTs, was performed to assess the relative clinical effectiveness of LDCT, CXR and usual care. The results showed that LDCT was ranked as the best screening strategy in terms of lung cancer mortality reduction. CXR had a 99.7% probability of being the worst intervention and usual care was ranked second. Cost-effectiveness - screening programmes are predicted to be more effective than no screening, reduce lung cancer mortality and result in more lung cancer diagnoses. Screening programmes also increase costs. Screening for lung cancer is unlikely to be cost-effective at a threshold of £20,000/quality-adjusted life-year (QALY), but may be cost-effective at a threshold of £30,000/QALY. The incremental cost-effectiveness ratio for a single screen in smokers aged 60-75 years with at least a 3% risk of lung cancer is £28,169 per QALY. Sensitivity and scenario analyses were conducted. Screening was only cost-effective at a threshold of £20,000/QALY in only a minority of analyses.

LIMITATIONS

Clinical effectiveness - the largest of the included RCTs compared LDCT with CXR screening rather than no screening. Cost-effectiveness - a representative cost to the NHS of lung cancer has not been recently estimated according to key variables such as stage at diagnosis. Certain costs associated with running a screening programme have not been included.

CONCLUSIONS

LDCT screening may be clinically effective in reducing lung cancer mortality, but there is considerable uncertainty. There is evidence that a single round of screening could be considered cost-effective at conventional thresholds, but there is significant uncertainty about the effect on costs and the magnitude of benefits.

FUTURE WORK

Clinical effectiveness and cost-effectiveness estimates should be updated with the anticipated results from several ongoing RCTs [particularly the NEderlands Leuvens Longkanker Screenings ONderzoek (NELSON) screening trial].

STUDY REGISTRATION

This study is registered as PROSPERO CRD42016048530.

FUNDING

The National Institute for Health Research Health Technology Assessment programme.

[Systemic Therapy for Low-grade Pulmonary Neuroendocrine Tumor]

肺部是神经内分泌肿瘤（neuroendocrine tumor, NET）的第二好发部位。肺类癌包括典型类癌和不典型类癌，属于低级别神经内分泌肿瘤。这一类肿瘤由于发病率较低，目前尚未得到广大医务工作者的重视。但有效的治疗不仅能提高患者的远期生存，还能控制患者症状，改善生活质量。本文分别阐述肺低级别神经内分泌肿瘤的流行病学和病理学特点、早期患者的治疗策略以及进展期患者的治疗策略。早期患者应当尽早进行手术治疗。进展期患者治疗方式包括化疗、SSAs、mTOR抑制剂、肽受体介导的放射性核素治疗、生物治疗以及靶向治疗。目前的研究结论大多来自其他部位的NETs研究外推而来，仍需针对肺低级别神经内分泌肿瘤患者进行特异性临床试验加以证实。

Neuroendocrine Tumor Diagnosis and Management: 68Ga-DOTATATE PET/CT

OBJECTIVE

The purpose of this article is to provide a review of the use of ⁶⁸Ga tetraazacyclododecanetetraacetic acid-DPhe1-Tyr3-octreotate (DOTATATE) PET/CT, a functional imaging modality for assessment of well-differentiated neuroendocrine tumors (NETs). It has become the preferred imaging modality for initial diagnosis, selection of patients for peptide receptor radionuclide therapy, and localization of unknown primary tumors. The National Comprehensive Cancer Network guideline has added ⁶⁸Ga-DOTATATE PET/CT as an appropriate test in the management of NETs.

CONCLUSION

In combination with FDG PET/CT, ⁶⁸Ga-DOTATATE PET/CT can noninvasively assess tumor heterogeneity, especially in G2 and G3 NETs, for personalized management of patients.

Prognostic significance of PD-L1 expression and CD8+ T cell infiltration in pulmonary neuroendocrine tumors

BACKGROUND

Recent research supports a significant role of immune checkpoint inhibitors in the treatment of solid tumors. However, relevant reports for programmed death-ligand 1 (PD-L1) and CD8+ tumor-infiltrating lymphocytes (TILs) in pulmonary neuroendocrine tumors (PNETs) have not been fully studied. Therefore, we investigated PNETs for the expression of PD-L1 and infiltration by CD8+ TILs as well as the prognostic value of both factors.

METHODS

In total, 159 specimens of PNETs (35 TC, 2 AC, 28 LCNEC, 94 SCLC) were included in this study. Immunohistochemistry (IHC) was used to detect the expression of PD-L1 in these cases. Cases demonstrating ≥5% tumor cell expression or any expression (> 1%) of PD-L1 on immune cells were considered positive. CD8+ TILs both within stroma and tumor areas of invasive carcinoma were analyzed using whole-slide digital imaging. Manual regional annotation and machine cell counts were performed for each case.

RESULTS

Positive expression of PD-L1 was observed in 72 cases (45.3%), including 9 cases (5.7%) with expression exclusively on tumor cells, 46 cases (28.9%) with expression exclusively on immune cells, and 17 cases (10.7%) with the expression on tumor cells and immune cells. PD-L1 expression was associated with necrosis (p < 0.001), high pathologic grade (p < 0.001) and histologic type (p < 0.001). No correlation was observed with overall survival (OS) (p = 0.158) or progression-free survival (PFS) (p = 0.315). In contrast, higher CD8+ T cell density was associated with the absence of vascular invasion (p = 0.004), histologic type (p = 0.005), negative lymph node metastasis (p = 0.005) and lower clinical staging (p = 0.007). Moreover, multivariate analysis revealed that CD8+ stromal TIL was an independent prognostic factor for improved OS (p = 0.009) and PFS (p = 0.002).

CONCLUSION

PD-L1 was expressed in approximately half of the PNETs. The majority of the expression was observed in immune cells. Positive expression of PD-L1 showed no correlation with OS or PFS, while higher CD8+ TILs within stroma was proved to be an independent prognostic factor for favorable OS and PFS of PNETs.

[Bronchial carcinoid tumor and recurrent pneumothoraxes]

Pneumothorax is a rare clinical manifestation of lung cancer. It can exceptionally reveal a bronchial carcinoid tumor. We present the case of a 27-year-old woman in whom recurrent pneumothoraxes were the clinical manifestation of a bronchial carcinoid tumor. The interest for chest computed tomography and bronchoscopy to identify etiology of secondary pneumothoraxes will be discussed.

Treatment of Lung Carcinosarcoma and Other Rare Histologic Subtypes of Non-small Cell Lung Cancer

OPINION STATEMENT

Lung carcinosarcoma (PCS) and other histological subtypes of non-small cell lung cancer, such as primary pulmonary lymphoma (PPL), pulmonary carcinoid (PC), and primary pulmonary lymphoepithelioma-like carcinoma (LELC), are rare. For their low incidence, the diagnosis and treatment are still controversial. Some patients only need surgery, while others may need chemotherapy, radiotherapy, or targeted therapy. In this paper, we retrospectively reviewed the literature of some rare histological subtype of NSCLC for the recent 20 years, and try to get some conclusions.

Impact of Timing of Lobectomy on Survival for Clinical Stage IA Lung Squamous Cell Carcinoma

BACKGROUND

Because the relationship between the timing of surgery following diagnosis of lung cancer and survival has not been precisely described, guidelines on what constitutes a clinically meaningful delay of resection of early-stage lung cancer do not exist. This study tested the hypothesis that increasing the time between diagnosis and lobectomy for stage IA squamous cell carcinoma (SCC) would be associated with worse survival.

METHODS

The association between timing of lobectomy and survival for patients with clinical stage IA SCC in the National Cancer Data Base (2006-2011) was assessed using multivariable Cox proportional hazards analysis and restricted cubic spline (RCS) functions.

RESULTS

The 5-year overall survival of 4,984 patients who met study inclusion criteria was 58.3% (95% CI, 56.3-60.2). Surgery was performed within 30 days of diagnosis in 1,811 (36%) patients, whereas the median time to surgery was 38 days (interquartile range, 23, 58). In multivariable analysis, patients who had surgery 38 days or more after diagnosis had significantly worse 5-year survival than patients who had surgery earlier (hazard ratio, 1.13 [95% CI, 1.02-1.25]; P = .022). Multivariable RCS analysis demonstrated the hazard ratio associated with time to surgery increased steadily the longer resection was delayed; the threshold time associated with statistically significant worse survival was ∼90 days or greater.

CONCLUSIONS

Longer intervals between diagnosis of early-stage lung SCC and surgery are associated with worse survival. Although factors other than the timing of treatment may contribute to this finding, these results suggest that efforts to minimize delays beyond those needed to perform a complete preoperative evaluation may improve survival.

Potential paraneoplastic syndromes and selected autoimmune conditions in patients with non-small cell lung cancer and small cell lung cancer: A population-based cohort study

BACKGROUND

Little is known about the occurrence and distribution of types of paraneoplastic syndromes (PNS) in patients with lung cancer. Identification of autoimmune PNS is particularly important for discerning them from immune-related adverse events of novel immunotherapies. We estimated the occurrence of PNS among patients with lung cancer and compared it with that in the general population.

METHODS

In this registry-based cohort study in Denmark, we identified all patients with incident primary lung cancer between 1997 and 2010, and in a general-population comparison cohort matched on calendar time, sex, age, and residence. Among patients with non-small cell lung cancer (NSCLC) and small-cell lung cancer (SCLC), we estimated prevalence of potential PNS and selected autoimmune conditions and compared their incidence rates with those of equivalent conditions in the general population cohort, using hazard ratios (HRs) adjusted for baseline comorbidity.

RESULTS

There were 35,319 patients with NSCLC and 6,711 patients with SCLC. The incidence rates per 1000 person-years (95% confidence interval) of any potential PNS or selected autoimmune disorders were 135.4 (131.9-139.1) among NSCLC patients and 237.3 (224.4-250.5) among SCLC patients. Adjusted HRs for any potential PNS or selected autoimmune disorders were 4.8 (4.7-5.0) for NSCLC and 8.2 (7.6-8.8) for SCLC.

CONCLUSION

Incidence rate of any potential PNS or selected autoimmune disorders among patients with lung cancer was greater than that in the general population and was greater after SCLC than after NSCLC.

IMPACT

These results provide context to discerning PNS from adverse effects of novel immunotherapies during the clinical course of NSCLC and SCLC.

Effects of the single and combined treatment with dopamine agonist, somatostatin analog and mTOR inhibitors in a human lung carcinoid cell line: an in vitro study

Somatostatin analogues and mTOR inhibitors have been used as medical therapy in lung carcinoids with variable results. No data are available on dopamine agonists as treatment for lung carcinoids. The main aim of the current study was to evaluate the effect of the combined treatment of somatostatin analogue octreotide and the dopamine agonist cabergoline with mTOR inhibitors in an in vitro model of typical lung carcinoids: the NCI-H727 cell line. In NCI-H727 cell line, reverse transcriptase-quantitative polymerase chain reaction and immunofluorescence were assessed to characterize the expression of the somatostatin receptor 2 and 5, dopamine receptor 2 and mTOR pathway components. Fifteen typical lung carcinoids tissue samples have been used for somatostatin receptor 2, dopamine receptor 2, and the main mTOR pathway component p70S6K expression and localization by immunohistochemistry. Cell viability, fluorescence-activated cell sorting analysis and western blot have been assessed to test the pharmacological effects of octreotide, cabergoline and mTOR inhibitors, and to evaluate the activation of specific cell signaling pathways in NCI-H727 cell line. NCI-H727 cell line expressed somatostatin receptor 2, somatostatin receptor 5 and dopamine receptor 2 and all mTOR pathway components at messenger and protein levels. Somatostatin receptor 2, dopamine receptor 2, and p70S6K (non phosphorylated and phosphorylated) proteins were expressed in most typical lung carcinoids tissue samples. Octreotide and cabergoline did not reduce cell viability as single agents but, when combined with mTOR inhibitors, they potentiate mTOR inhibitors effect after long-term exposure, reducing Akt and ERK phosphorylation, mTOR escape mechanisms, and increasing the expression DNA-damage-inducible transcript 4, an mTOR suppressor. In conclusion, the single use of octreotide and cabergoline is not sufficient to block cell viability but the combined approach of these agents with mTOR inhibitors might reduce the mTOR inhibitors-induced escape mechanisms and/or activate the endogenous mTOR suppressor, potentiating the effect of the mTOR inhibitors in an in vitro model of typical lung carcinoids.

Lung neuroendocrine tumours: deep sequencing of the four World Health Organization histotypes reveals chromatin-remodelling genes as major players and a prognostic role for TERT, RB1, MEN1 and KMT2D

Next-generation sequencing (NGS) was applied to 148 lung neuroendocrine tumours (LNETs) comprising the four World Health Organization classification categories: 53 typical carcinoid (TCs), 35 atypical carcinoid (ACs), 27 large-cell neuroendocrine carcinomas, and 33 small-cell lung carcinomas. A discovery screen was conducted on 46 samples by the use of whole-exome sequencing and high-coverage targeted sequencing of 418 genes. Eighty-eight recurrently mutated genes from both the discovery screen and current literature were verified in the 46 cases of the discovery screen, and validated on additional 102 LNETs by targeted NGS; their prevalence was then evaluated on the whole series. Thirteen of these 88 genes were also evaluated for copy number alterations (CNAs). Carcinoids and carcinomas shared most of the altered genes but with different prevalence rates. When mutations and copy number changes were combined, MEN1 alterations were almost exclusive to carcinoids, whereas alterations of TP53 and RB1 cell cycle regulation genes and PI3K/AKT/mTOR pathway genes were significantly enriched in carcinomas. Conversely, mutations in chromatin-remodelling genes, including those encoding histone modifiers and members of SWI-SNF complexes, were found at similar rates in carcinoids (45.5%) and carcinomas (55.0%), suggesting a major role in LNET pathogenesis. One AC and one TC showed a hypermutated profile associated with a POLQ damaging mutation. There were fewer CNAs in carcinoids than in carcinomas; however ACs showed a hybrid pattern, whereby gains of TERT, SDHA, RICTOR, PIK3CA, MYCL and SRC were found at rates similar to those in carcinomas, whereas the MEN1 loss rate mirrored that of TCs. Multivariate survival analysis revealed RB1 mutation (p = 0.0005) and TERT copy gain (p = 0.016) as independent predictors of poorer prognosis. MEN1 mutation was associated with poor prognosis in AC (p = 0.0045), whereas KMT2D mutation correlated with longer survival in SCLC (p = 0.0022). In conclusion, molecular profiling may complement histology for better diagnostic definition and prognostic stratification of LNETs. © 2016 The Authors. The Journal of Pathology published by John Wiley & Sons Ltd on behalf of Pathological Society of Great Britain and Ireland.

Well-differentiated bronchial neuroendocrine tumors: Clinical management and outcomes in 105 patients

INTRODUCTION

Bronchial neuroendocrine tumors (NETs) are rare tumors representing approximately 20%-30% of all neuroendocrine tumors and 2%-3% of all adult lung cancers. Here, they present a large case series of well-differentiated bronchial NETs with the aim of investigating the behavior of these tumors and long-term outcomes.

METHODS

A retrospective review was performed of 105 patients with bronchial NETs managed in a tertiary referral center in the period between January 1998 and January 2012.

RESULTS

Bronchial NETs are commoner in females and the commonest presenting symptoms were cough (13.9%) and dyspnoea (11.6%). Octreoscan^TM and Gallium-68 DOTATATE PET were found to have similar diagnostic sensitivity and FDG PET was more sensitive for higher-grade tumors. Over a median follow-up period of 35.5 months mortality rate was 5.7%. The 5-year survival was 76% and the 10-year survival was 62%. Female patients survived longer but this difference was not statistically significant (P = .59). Older age greater than 50 years (P = .027), higher levels of Chromogranin A (CgA) (P = .034), first-line treatment with surgery (P = .005), ki67 over 10% (P = .037), and tumor stage (P = .036) but not tumor grade (P = .22), were significantly associated with survival.

DISCUSSION

Several factors have been identified which are independently associated with survival including CgA levels greater than 100 pmol/L, tumor stage, age greater than 50, ki67 over 10% and having surgery as first-line treatment. There was no difference in survival between typical and atypical carcinoids.

Current understanding and approach to well differentiated lung neuroendocrine tumors: an update on classification and management

Neuroendocrine tumors (NETs) are rare neoplasms that can arise from any tissue. They are classified based on embryonic gut derivative (i.e. foregut, midgut and hindgut) with midgut tumors being the most common (e.g. gastrointestinal NET). The second most common category of NETs is that which arises from the lung. In fact, 25% of primary lung cancers are NETs, including small cell lung cancer (SCLC), which comprises 20% of all lung cancers. The remaining 5% are large cell neuroendocrine cancer (LCNEC, 3%), typical carcinoids (TCs, 1.8%), and atypical carcinoids (ACs, 0.2%). The less common TCs/ACs are well differentiated lung NETs. Their incidence has been increasing in more recent years and although these tumors are slow growing, advanced disease is associated with poor survival. There have been advances in classification of lung NETs that have allowed for more appropriate management upfront. They are cured by surgical resection when disease is limited. However, advanced and metastatic disease requires medical therapy that is ever changing and expanding. In this review, the aim is to summarize the current understanding and classification of well differentiated lung NETs (i.e. TCs and ACs), and focus on recent updates in medical management of advanced disease, along with a brief discussion on potential future discoveries.

Endobronchial Carcinoid and Concurrent Carcinoid Syndrome in an Adolescent Female

Endobronchial carcinoid tumors are the most common intrabronchial tumors in children and adolescents. Common signs and symptoms include persistent cough and wheezing not responsive to bronchodilators, hemoptysis, and recurrent fever. Diagnosis is frequently made by imaging and direct visualization with flexible bronchoscopy; surgery remains the gold standard treatment, and lung-sparing resections should be performed whenever possible. Though carcinoid syndrome—characterized by flushing, palpitations, wheezing, shortness of breath, and diarrhea—has been found in association with adult bronchial carcinoid tumors, to our knowledge only one previous study has reported the presence of carcinoid syndrome in a pediatric patient with an endobronchial carcinoid. Here, we report a case of a 14-year-old girl with chronic cough found to have an endobronchial carcinoid tumor and signs and symptoms consistent with carcinoid syndrome.

Diffuse Idiopathic Pulmonary Neuroendocrine Cell Hyperplasia and Granulomatous Inflammation Mimicking High-Grade Malignancy on FDG-PET/CT

Diffuse idiopathic pulmonary neuroendocrine cell hyperplasia (DIPNECH) is a rare form of preinvasive lung lesion associated with indolent carcinoid tumor formation. This disease is characterized by multiple small pulmonary nodules with low SUVmax on F-FDG PET. Biopsy and immunohistochemical staining for neuroendocrine markers confirm diagnosis. There is no consensus for treatment, which typically involves surgical excision or management of symptoms with steroid-based therapies. We report an unusual case of DIPNECH colocalizing with necrotizing granulomatous inflammation mimicking high-grade aggressive malignancy on FDG-PET and a typical case of DIPNECH for comparison with low FDG avidity.

Pulmonary Neuroendocrine Tumors: Part II. Treatment

Pulmonary neuroendocrine tumors that arise from Kulchitzky cells of the bronchial mucosa consist of a spectrum of histologic features leading to a variable prognosis. Although typical carcinoid represents the most benign course, small-cell cancer has the grimmest outcome. Therefore, differentiating the spectrum of neuroendocrine tumors helps one not only to determine the prognosis, but also to guide the treatment options. In this part, we aim to discuss the treatment options in pulmonary neuroendocrine tumors except for small-cell lung cancer.

Is Close Surveillance Indicated for Indolent Cancers? The Carcinoid Story

The objective of this article is to determine the relevance of close postresection surveillance for bronchopulmonary carcinoid. From 2006 to 2013, 57 patients underwent lung resection for bronchopulmonary carcinoid. They were assessed for effects of clinical presentation, subtype, stage, and tobacco use on survival and recurrence. Utility of bronchoscopy and radiographic surveillance was reviewed. Mean follow-up was 2.1 ± 1.7 years. Carcinoid patients presented at a young age (51 ± 15 years) with normal spirometry regardless of smoking status (forced 1-second expiratory volume, 88% ± 19% for never smokers vs 87% ± 16% for smokers). Thirty-nine patients underwent a lobectomy (2 sleeve resections) and 11 pneumonectomy or bilobectomy. Most carcinoids were of the typical (n = 53, 93%) rather than atypical (n = 4, 7.0%) subtype. Staging from pathology was unaffected by smoking status. Eight patients had positive lymph nodes at resection (13% of typical and 25% of atypical subtypes). One recurrence was an atypical pN0 carcinoid. Of 57 patients, 18 were surveilled postoperatively with bronchoscopy, which revealed no recurrences. Furthermore, 146 follow-up computed tomography scans were performed on 53 of 57 patients. No typical carcinoid recurrences were identified by any postresection surveillance technique, regardless of stage. Bronchopulmonary carcinoid is a different entity from non-small cell lung cancer and has low recurrence and mortality risks independent of smoking status. It is hard to justify close surveillance following complete resection of typical carcinoid. Computed tomography scans at 5-year intervals might be reasonable and more cost effective.

Differential miRNA-Expression as an Adjunctive Diagnostic Tool in Neuroendocrine Tumors of the Lung

Pulmonary malignancies with neuroendocrine differentiation represent a rare subclass of lung carcinomas, which vary in the extent of differentiation and grade of biological aggressiveness. In particular, neuroendocrine tumors are classified into well differentiated typical and atypical carcinoids as well as poorly differentiated large cell neuroendocrine and small cell lung carcinomas. Tiny MicroRNAs have been identified as reliable classifiers in distinct cancer types and seem to play important roles in cellular processes like regulation of cell growth, differentiation and apoptosis. In the present study, two different microRNAs (miR-21 and miR-34a) were explored for their involvements in pathogenesis of subtypes and finally in differential diagnosis of pulmonary neuroendocrine tumors. miR-21 was upregulated in poorly differentiated neuroendocrine tumors (mean rank: 26.8; 28.75) as compared to carcinoids (mean rank: 12.33; 12.07) with a significance of 0.00033. High-expression levels of miR-34a were associated with atypical carcinoids (p = 0.010). A close association is implicated between the elevated miR-21 values in high-grade and miR-34a patterns in low-grade atypical neuroendocrine lung carcinomas, which could potentially be exploited as practical supportive markers for differential lung cancer diagnosis in routine. However, some additional extended research and validation studies are needed to utilize them as routine markers or potential molecular targets for personalized medicine.

Clinical features of gastroenteropancreatic tumours

Gastroenteropancreatic (GEP) endocrine tumours (carcinoids and pancreatic islet cell tumours) are composed of multipotent neuroendocrine cells that exhibit a unique ability to produce, store, and secrete biologically active substances and cause distinct clinical syndromes. The classification of GEP tumours as functioning or non-functioning is based on the presence of symptoms that accompany these syndromes secondary to the secretion of hormones, neuropeptides and/or neurotransmitters (functioning tumours). Non-functioning tumours are considered to be neoplasms of neuroendocrine differentiation that are not associated with obvious symptoms attributed to the hypersecretion of metabolically active substances. However, a number of these tumours are either capable of producing low levels of such substances, which can be detected by immunohistochemistry but are insufficient to cause symptoms related to a clinical syndrome, or alternatively, they may secrete substances that are either metabolically inactive or inappropriately processed. In some cases, GEP tumours are not associated with the production of any hormone or neurotransmitter. Both functioning and non-functioning tumours can also produce symptoms due to mass effects compressing vital surrounding structures. Gastroenteropancreatic tumours are usually classified further according to the anatomic site of origin: foregut (including respiratory tract, thymus, stomach, duodenum, and pancreas), midgut (including small intestine, appendix, and right colon), and hindgut (including transverse colon, sigmoid, and rectum). Within these subgroups the biological and clinical characteristics of the tumours vary considerably, but this classification is still in use because a significant number of previous studies, mainly observational, have used it extensively.

Multicenter comparison of 18F-FDG and 68Ga-DOTA-peptide PET/CT for pulmonary carcinoid

PURPOSE

The aims of this study were to retrospectively evaluate and compare the detection rate (DR) of 68Ga-DOTA-peptide and 18F-FDG PET/CT in the preoperative workup of patients with pulmonary carcinoid (PC) and to assess the utility of various functional indices obtained with the 2 tracers in predicting the histological characterization of PC, that is, typical versus atypical.

METHODS

Thirty-three consecutive patients with confirmed PC referred for 18F-FDG and 68Ga-DOTA-peptide PET/CT in 2 centers between January 2009 and April 2013 were included. The semiquantitative evaluation included the SUV max, the SUV of the tumor relative to the maximal liver uptake for 18F-FDG (SUV T/L) or the maximal spleen uptake for 68Ga-DOTA-peptides (SUV T/S), the ratio between SUV max of 68Ga-DOTA-peptides PET/CT, and the SUV max of 18F-FDG PET/CT (SUV max ratio). Histology was used as reference standard.

RESULTS

Definitive diagnosis consisted of 23 typical carcinoids (TCs) and 10 atypical carcinoids. 18F-FDG PET/CT was positive in 18 cases and negative in 15 (55% DR). 68Ga-DOTA-peptide PET/CT was positive in 26 cases and negative in 7 (79% DR). In the subgroup analysis, 68Ga-DOTA-peptide PET/CT was superior in detecting TC (91% DR; P < 0.001), whereas 18F-FDG PET/CT was superior in detecting atypical carcinoid (100% DR; P = 0.04). The SUV max ratio was the most accurate semiquantitative index in identifying TC.

CONCLUSIONS

Overall diagnostic performance of PET/CT in detecting PC is optimal when integrating 18F-FDG and 68Ga-DOTA-peptide PET/CT findings. In the subgroup analysis, the SUV max ratio seems to be the most accurate index in predicting TC. Both methods should be performed when PC is suspected or when the histological subtype is undefined.

Co-expression of TTF-1 and neuroendocrine markers in the human fetal lung and pulmonary neuroendocrine tumors

The expression pattern of thyroid transcription factor 1 (TTF-1) and neuroendocrine markers, neuron cell adhesion molecule (NCAM; CD56), chromogranin A (CgA) and synaptophysin (Syp), of different lung cell lineages was histologically analyzed in 15 normal human fetal lungs and 12 neuroendocrine tumors (NETs) using immunohistochemical methods. During pseudoglandular phase strong nuclear TTF-1 staining was detected in the columnar nonciliated epithelial cells, while NCAM, CgA and Syp had a moderate expression in the proximal airways and mild expression in the distal airways. Neuroendocrine cells (NECs) in proximal lung airway were co-localizing TTF-1 and other neuroendocrine markers while neuroendocrine bodies (NEBs) exhibit only staining with NCAM and Syp. In the canalicular phase TTF-1 nuclear staining was expressed only in several epithelial cells in proximal airways, while budding airways epithelium showed strong TTF-1 expression. Expression of NCAM, CgA and Syp in this phase equals the one in pseudoglandular phase. NEBs cells were co-localizing TTF-1 and NCAM in proximal airways and few NECs in distal airway were co-localizing TTF-1 and Syp. TTF-1 staining in the saccular phase was limited to subsets of epithelial cells in the proximal airways with stronger positivity in the distal airways. NCAM expression is moderate only in proximal airways, while Syp and CgA show mild expression in proximal and distal airways. NECs were co-localizing TTF-1 and NCAM in proximal lung airway. With regard to NECs, all small cell lung cancer (SCLC) cells had strong TTF-1, NCAM, Syp and CgA positivity and TTF-1 co-localized with other neuroendocrine markers. All pulmonary typical carcinoids were TTF-1 negative, while pulmonary atypical carcinoids were focal positive for TTF-1 and some neoplastic cells co-localized TTF-1 with neuroendocrine markers. Our results indicate that TTF-1 expression in NECs suggests a possible role in their normal development and differentiation. Our results also indicate that possible cell of origin for poorly differentiated SCLC and some atypical carcinoid could be a progenitor cell in neuroendocrine lineage while in typical carcinoids possible cell of origin is localized in terminally differentiated NECs.