Management of pulmonary neuroendocrine tumors

[Pulmonary neuroendocrine tumors : Current review]

CLINICAL ISSUE

Neuroendocrine neoplasms of the lung are a heterogenous tumor group. The pathological classification comprises diffuse idiopathic pulmonary neuroendocrine cell hyperplasia, classic neuroendocrine tumors, and neuroendocrine carcinoma. Classic neuroendocrine tumors include typical and atypical carcinoid tumors.

DIAGNOSTIC WORK-UP

Imaging plays an important role in diagnosis and can help in identifying the tumor biology. Overall, this tumor group is rare, comprising less than 2% of all thoracic tumors.

PRACTICAL RECOMMENDATIONS

In the current review, the various tumors are presented and important aspects regarding pathological classification, imaging modalities, and treatment are described.

Diagnostic Anatomic Imaging for Neuroendocrine Neoplasms: Maximizing Strengths and Mitigating Weaknesses

ABSTRACT

Neuroendocrine neoplasms are a heterogeneous group of gastrointestinal and lung tumors. Their diverse clinical manifestations, variable locations, and heterogeneity present notable diagnostic challenges. This article delves into the imaging modalities vital for their detection and characterization. Computed tomography is essential for initial assessment and staging. At the same time, magnetic resonance imaging (MRI) is particularly adept for liver, pancreatic, osseous, and rectal imaging, offering superior soft tissue contrast. The article also highlights the limitations of these imaging techniques, such as MRI's inability to effectively evaluate the cortical bone and the questioned cost-effectiveness of computed tomography and MRI for detecting specific gastric lesions. By emphasizing the strengths and weaknesses of these imaging techniques, the review offers insights into optimizing their utilization for improved diagnosis, staging, and therapeutic management of neuroendocrine neoplasms.

Current and emerging strategies for the management of advanced/metastatic lung neuroendocrine tumors

Pulmonary neuroendocrine tumors represent a spectrum of disease ranging from typical carcinoid tumors to small cell lung cancers. The incidence of low-grade pulmonary NETs has been increasing, leading to improved awareness and the need for more treatment options for this rare cancer. Somatostatin analogs continue to be the backbone of therapy and may be followed or accompanied by targeted therapy, chemotherapy, and immune therapy. The recent addition of peptide receptor radionuclide therapy (PRRT) to the treatment armamentarium of NETs has led to the development of targeted alpha therapy to overcome PRRT resistance and minimize off-target adverse effects. Herein, we aim to highlight current treatment options for patients with advanced low grade pulmonary NETs along with emerging therapies, sequencing of therapies, upcoming clinical trials, and the importance of a multidisciplinary team to improve patient outcomes.

Virus-associated neuroendocrine cancers: Pathogenesis and current therapeutics

Neuroendocrine neoplasms (NENs) comprise malignancies involving neuroendocrine cells that often lead to fatal pathological conditions. Despite escalating global incidences, NENs still have poor prognoses. Interestingly, research indicates an intricate association of tumor viruses with NENs. However, there is a dearth of comprehension of the complete scenario of NEN pathophysiology and its precise connections with the tumor viruses. Interestingly, several cutting-edge experiments became helpful for further screening of NET for the presence of polyomavirus, Human papillomavirus (HPV), Kaposi sarcoma-associated herpesvirus (KSHV), Epstein Barr virus (EBV), etc. Current research on the neuroendocrine tumor (NET) pathogenesis provides new information concerning their molecular mechanisms and therapeutic interventions. Of note, scientists observed that metastatic neuroendocrine tumors still have a poor prognosis with a palliative situation. Different oncolytic vector has already demonstrated excellent efficacies in clinical studies. Therefore, oncolytic virotherapy or virus-based immunotherapy could be an emerging and novel therapeutic intervention. In-depth understanding of all such various aspects will aid in managing, developing early detection assays, and establishing targeted therapeutic interventions for NENs concerning tumor viruses. Hence, this review takes a novel approach to discuss the dual role of tumor viruses in association with NENs' pathophysiology as well as its potential therapeutic interventions.

Added prognostic value of molecular imaging parameters over proliferation index in typical lung carcinoid: an [18F]FDG PET/CT and SSTR imaging study

OBJECTIVE

This study was performed to evaluate the prognostic meaning of volumetric and semi-quantitative parameters measured using [18F]FDG PET/CT and somatostatin receptor (SSTR) imaging in patients with typical lung carcinoid (TC), and their relationship with proliferative index (Ki67).

METHODS

We retrospectively reviewed 67 patients (38-94 years old, mean: 69.7) with diagnosis of TC who underwent [18F]FDG PET/CT and/or SSTR scintigraphy/SPECT with [111In]DTPA-Octreotide plus contrast-enhanced CT (CECT) at staging evaluation. All patients had Ki67 measured and a follow-up (FU) of at least 1 year. SSTR density (SSTRd) was calculated as the percentage difference of tumor/non-tumor ratio at 4 and 24 h post-injection. At PET/CT, metabolic activity was measured using SUVmax and SUVratio; volumetric parameters included MTV and TLG of the primary tumor, measured using the threshold SUV41%. ROC analysis, discriminant analysis and Kaplan-Meier curves (KM) were performed.

RESULTS

11 patients died during FU. Disease stage (localized versus advanced), SUVratio, SUVmax, Ki67, MTV and TLG were significantly higher in non-survivors than in survivors. ROC curves resulted statistically significant for Ki67, SUVratio, SUVmax, MTV and TLG. On multivariate analysis, stage of disease and TLG were significant independent predictors of overall survival (OS). In KM curves, the combination of disease stage and TLG identified four groups with significantly different outcomes (p < 0.005). Metabolic activity (SUVmax and SUVratio) was confirmed as significant independent prognostic factor for OS also in patients with advanced disease, with the best AUC using SUVmax. In patients with advanced and localized disease, SSTRd proved to be the best imaging prognostic factor for progression and for disease-free survival (DFS), respectively. In localized disease, SSTRd 31.5% identified two subgroups of patients with significant different DFS distribution and in advanced disease, a high cutoff value (58.5%) was a significant predictor of adverse prognosis.

CONCLUSION

Volumetric and semi-quantitative parameters measured using [18F]FDG PET/CT and SSTR imaging combined with Ki67 may provide a reference for prognosis evaluation of patients with TC, to better stratify risk groups with the goal of developing individualized therapeutic strategies.

Radiomics in pulmonary neuroendocrine tumours (NETs)

Objectives

The aim of this single-centre, observational, retrospective study is to find a correlation using Radiomics between the analysis of CT texture features of primary lesion of neuroendocrine (NET) lung cancer subtypes (typical and atypical carcinoids, large and small cell neuroendocrine carcinoma), Ki-67 index and the presence of lymph nodal mediastinal metastases.

Methods

Twenty-seven patients (11 males and 16 females, aged between 48 and 81 years old—average age of 70,4 years) with histological diagnosis of pulmonary NET with known Ki-67 status and metastases who have performed pre-treatment CT in our department were included. All examinations were performed with the same CT scan (Sensation 16-slice, Siemens). The study protocol was a baseline scan followed by 70 s delay acquisition after administration of intravenous contrast medium. After segmentation of primary lesions, quantitative texture parameters of first and higher orders were extracted. Statistics nonparametric tests and linear correlation tests were conducted to evaluate the relationship between different textural characteristics and tumour subtypes.

Results

Statistically significant (p < 0.05) differences were seen in post-contrast enhanced CT in multiple first and higher-order extracted parameters regarding the correlation with classes of Ki-67 index values. Statistical analysis for direct acquisitions was not significant. Concerning the correlation with the presence of metastases, one histogram feature (Skewness) and one feature included in the Gray-Level Co-occurrence Matrix (ClusterShade) were significant on contrast-enhanced CT only.

Conclusions

CT texture analysis may be used as a valid tool for predicting the subtype of lung NET and its aggressiveness.

Platinum Doublet plus Atezolizumab as First-line Treatment in Metastatic Large Cell Neuroendocrine Carcinoma: A Single Institution Experience

BACKGROUND

Large Cell Neuroendocrine Carcinoma of the Lung (L-LCNEC) is a rare type of neuroendocrine lung cancer that is increasingly diagnosed. However, the optimal management regarding the advanced stage is unclear. The purpose of this article is to present and compare our experience when L-LCNEC is treated as Small Cell Lung Cancer (SCLC).

PATIENTS AND METHODS

Overall, eight cases of L-LCNEC were included. We retrospectively reviewed medical files and reports by accessing the Institution's Data of patients diagnosed with L-LCNEC from April 2019 until December 2020 and evaluated their response to the combination of Platinum - Etoposide - Atezolizumab as first-line chemotherapy.

RESULTS

The overall observed response rate (ORR) of 75%. The median PFS was 6.85 months. The median response duration was 5.5 months.

CONCLUSIONS

Comparing our findings with other retrospective and prospective studies, it seems that the systematic treatment of choice and management in L-LCNEC of the lung should be that of a small cell carcinoma of the lung.

Clinical Significance of CYFRA21-1, AFP, CA-153, CEA, and CA-199 in the Diagnosis of Lung Cancer Ocular Metastasis in Hypertension Population

Purpose: To detect lung metastases, we conducted a retrospective study to improve patient prognosis.

Methods: Hypertension patients with ocular metastases (OM group; n = 58) and without metastases (NM group; n = 1,217) were selected from individuals with lung cancer admitted to our hospital from April 2005 to October 2019. The clinical characteristics were compared by Student's t-test and chi-square test. Independent risk factors were identified by binary logistic regression, and their diagnostic value evaluated by receiver operating characteristic curve analysis.

Results: Age and sex did not differ significantly between OM and NM groups; There were significant differences in pathological type and treatment. Adenocarcinoma was the main pathological type in the OM group (67.24%), while squamous cell carcinoma was the largest proportion (46.43%) in the NM group, followed by adenocarcinoma (34.10%). The OM group were treated with chemotherapy (55.17%), while the NM group received both chemotherapy (39.93%) and surgical treatment (37.06%). Significant differences were detected in the concentrations of cancer antigen (CA)−125, CA-199, CA-153, alpha fetoprotein (AFP), carcinoembryonic antigen (CEA), cytokeratin fraction 21-1 (CYFRA21-1), total prostate-specific antigen, alkaline phosphatase, and hemoglobin (Student's t-test). Binary logistic regression analysis indicated that CA-199, CA-153, AFP, CEA, and CYRFA21-1 were independent risk factors for lung cancer metastasis. AFP (98.3%) and CEA (89.3%) exhibited the highest sensitivity and specificity, respectively, while CYRFA21-1 had the highest area under the ROC curve value (0.875), with sensitivity and specificity values of 77.6 and 87.0%, respectively. Hence, CYFRA21-1 had the best diagnostic value.

Prevalence of Delta-Like Protein 3 in a Consecutive Series of Surgically Resected Lung Neuroendocrine Neoplasms

Delta-like protein 3 (DLL3) is a protein of the Notch pathway, and it is a potential therapeutic target for high-grade lung neuroendocrine tumors (NETs), i.e., small cell lung carcinoma (SCLC) and large cell neuroendocrine carcinoma (LCNEC). However, DLL3 prevalence in lung NETs and its association with clinicopathological characteristics and prognosis remained unclear. We analyzed the immunohistochemical expression of DLL3 and its prognostic role in a consecutive series of 155 surgically resected lung NETs, including typical carcinoid (TC), atypical carcinoid (AC), LCNEC, and SCLC patients. The DLL3 expression was categorized as high (>50% positive tumor cells) or low (<50%). In addition, tumors were categorized by H-score (i.e., percentage of positive cells by staining intensity, ≥150 vs. <150). DLL3 staining was positive in 99/155 (64%) samples, and high DLL3 expression was frequently observed in high-grade tumors. In detail, 46.9% and 75% of SCLC and 48.8% and 53.7% of LCNEC specimens showed a high DLL3 expression by using H-score and percentage of positive tumor cells, respectively. Regarding low-grade NETs, only 4.9% and 12.2% TCs and 19.5% and 24.4% ACs had high DLL3 expression considering H-score and percentage of positive tumor cells, respectively. High DLL3 expression was associated with advanced American Joint Committee on Cancer (AJCC) stage, peripheral location, and chromogranin A expression in high-grade tumors (p < 0.05). In low-grade NETs, high DLL3 expression was associated with female sex, peripheral location, a higher number of mitoses, higher Ki-67 index, presence of necrosis, and pleural infiltration (p < 0.05). No association was observed between high DLL3 expression and overall survival (OS) and disease-free survival (DFS) in high-grade NETs, whereas high DLL3 expression was associated with lower DFS in ACs (p = 0.01). In conclusion, our study demonstrated a high prevalence of DLL3 expression in high-grade lung NET patients and its association with aggressive clinicopathological features. These findings confirm that DLL3 could represent a useful biomarker for target therapy in high-grade tumors. Our results also suggest that the DLL3 expression could identify a subset of AC tumors with more aggressive behavior, thus providing the basis for new therapeutic options in this group of patients.

Imaging neuroendocrine tumors: Characterizing the spectrum of radiographic findings

Neuroendocrine tumors (NET) are a group of neoplasms with neuroendocrine differentiation affecting a wide range of organs. Functional NETs present with symptoms due to the particular hormone produced. Functional NETs are usually small at diagnosis and therefore can be challenging to diagnose. In contrast, non-functioning NETs are generally larger and present with mass effect. Imaging plays an indispensable role in diagnosis, staging and management of patients with NETs. The optimal modality and technique for imaging of NETs depend on the location of primary and metastatic lesions. Regardless of the imaging modality, dynamic contrast-enhanced imaging is essential for evaluation of NETs. In general, CT scan is typically the primary imaging modality for evaluating NETs. MRI is used as a complementary modality, being superior to other modalities to assess liver metastasis. Nuclear medicine imaging is also widely used in NET assessment.

Case Report: Unmasking Hypercalcemia in Patients With Neuroendocrine Neoplasms. Experience From Six Italian Referral Centers

BACKGROUND

Hypercalcemia is a common paraneoplastic syndrome which can occur in up to 10% of patients with advanced neoplasms. Paraneoplastic parathyroid hormone-related protein (PTHrP) represents the most frequent cause of this syndrome. In neuroendocrine neoplasms (NENs) paraneoplastic hypercalcemia is rare.

CASE SERIES

The present series includes all patients with NENs and paraneoplastic hypercalcemia from four Italian centres: (I) A 40-year-old man was hospitalized for repeated episodes of falls, hyposthenia and drowsiness. Severe hypercalcemia was found. Metastatic pancreatic G2 NEN and PTHrP-related hypercalcemia were diagnosed. The patient started therapy with somatostatin analogs (SSA) and Denosumab. After disease progression peptide receptor radionuclide therapy (PRRT) was started with an objective response associated with PTHrP reduction and normocalcemia. (II) A 45-year-old man was referred for pancreatic G2 NEN. SSA and subsequently everolimus were administered for metastases occurrence. Hypercalcemia occurred and PRRT and Denosumab were started for disease progression with the onset of bone metastases. Despite disease stability after four cycles of PRRT the patient's performance status worsened until death. (III) A 49-year-old woman was hospitalized for psychic slowdown, confusional state, sensory dullness. A severe hypercalcemia, associated with a pancreatic G1 NEN was diagnosed and treated with haemodialysis, bisphosphonates injections and continuous infusion of calcitonin. 1,25-dihydroxyvitamin D was high, PTHrP was undetectable. After surgery serum calcium levels and 1,25-dihydroxyvitamin D were normalized. (IV) A 69-year-old man was hospitalized after the onset of shortness of breath and dyspnea, asthenia and weight loss. Computed Tomography (CT) and ⁶⁸Ga DOTATOC Positron Emission Tomography (PET)-CT revealed a left pulmonary nodule. Hypercalcemia and markedly elevated PTHrP levels were detected. The histological examination revealed an atypical carcinoid. After surgery, calcium levels were normalized, PTHrP was significantly reduced with an improvement of general conditions.

CONCLUSION

In our series, paraneoplastic PTHrP-related hypercalcemia occurred in pancreatic NEN and in one bronchial carcinoid representing the third case in the literature. Our case associated with 1,25-dihydroxyvitamin D secretion represents the fourth case in the literature. PTHrP secretion should be considered in NENs' patients with hypercalcemia. Acute treatment should be focused on lowering calcium levels, and long-term control can be achieved by tumor cytoreduction inhibiting PTHrP release.

Clinical implications of lung neuroendocrine neoplasm classification

INTRODUCTION

Neuroendocrine neoplasms of the lung (Lung NENs) encompass NE tumors (NETs), which are in turn split into typical and atypical carcinoids, and NE carcinomas (NECs), which group together small-cell carcinoma and large-cell NE carcinoma. This classification is the current basis for orienting the daily practice of these patients, with diagnostic, prognostic, and predictive inferences.

AREAS COVERED

The clinical implications of lung NEN classification are addressed according to three converging perspectives, which were dissected through an extensive literature overview: (1) how to put intratumor heterogeneity into the context of the current classification; (2) how to contextualize immunohistochemistry markers to improve diagnosis, prognosis, and therapy prediction; and (3) how to use immuno-oncology strategies for life-threatening NECs, which still account for 90% or more of lung NENs.

EXPERT OPINION

We provide practical insights to account for intratumor heterogeneity, practice the choice of immunohistochemistry markers, and emphasize once again the added value of immuno-oncology in the setting of personalized medicine of lung NENs.

Classifying Lung Neuroendocrine Neoplasms through MicroRNA Sequence Data Mining

Lung neuroendocrine neoplasms (NENs) can be challenging to classify due to subtle histologic differences between pathological types. MicroRNAs (miRNAs) are small RNA molecules that are valuable markers in many neoplastic diseases. To evaluate miRNAs as classificatory markers for lung NENs, we generated comprehensive miRNA expression profiles from 14 typical carcinoid (TC), 15 atypical carcinoid (AC), 11 small cell lung carcinoma (SCLC), and 15 large cell neuroendocrine carcinoma (LCNEC) samples, through barcoded small RNA sequencing. Following sequence annotation and data preprocessing, we randomly assigned these profiles to discovery and validation sets. Through high expression analyses, we found that miR-21 and -375 are abundant in all lung NENs, and that miR-21/miR-375 expression ratios are significantly lower in carcinoids (TC and AC) than in neuroendocrine carcinomas (NECs; SCLC and LCNEC). Subsequently, we ranked and selected miRNAs for use in miRNA-based classification, to discriminate carcinoids from NECs. Using miR-18a and -155 expression, our classifier discriminated these groups in discovery and validation sets, with 93% and 100% accuracy. We also identified miR-17, -103, and -127, and miR-301a, -106b, and -25, as candidate markers for discriminating TC from AC, and SCLC from LCNEC, respectively. However, these promising findings require external validation due to sample size.

High Expression of NEK2 and PIM1, but Not PIM3, Is Linked to an Aggressive Phenotype of Bronchopulmonary Neuroendocrine Neoplasms

Dysregulations of the NEK2 and PIM1-3 kinase signaling axes have been implicated in the pathogenesis of several cancers, including those with a neuroendocrine phenotype. However, their impact on bronchopulmonary neuroendocrine neoplasms (BP-NENs) has not been investigated. The aim of this pilot study was to determine mRNA and protein levels of NEK2, PIM1, and PIM3 in a group of 49 patients with BP-NENs: 11 typical carcinoids, 5 atypical carcinoids, 11 large cell neuroendocrine carcinomas, 22 small cell lung carcinomas (SCLC). The expression was measured using TaqMan-based RT-PCR and immunohistochemistry. NEK2 and PIM1 mRNA levels were higher in the SCLC patients than in the other BP-NEN groups (p < 0.001). There was an association between NEK2 mRNA and protein expression (p = 0.023) and elevated NEK2 mRNA levels were related to reduced survival in BP-NEN patients (p = 0.015). Patients with higher PIM1 protein expression had also diminished survival comparing with those with weak or no PIM1 expression (p = 0.037). Elevated NEK2 and PIM1 expression were related to aggressive tumor phenotype and indirectly affected the overall survival of BP-NEN patients. Our pilot study supports the need for future investigation of the biological function of NEK2 and PIM1 in BP-NEN transformation to verify the clinical value of our findings.

Post FDA approval analysis of 200 gallium-68 DOTATATE imaging: A retrospective analysis in neuroendocrine tumor patients

Gallium-68 DOTATATE provides physiologic imaging and assists in disease localization for somatostatin receptor (SSTR) positive neuroendocrine tumor (NET) patients. However, questions regarding usefulness of gallium- 68 DOTATATE imaging in identifying the primary site in neuroendocrine tumors (NETS) of unknown primary, correlation of NET grade with median Standardized Uptake Value (SUV) and effects of long acting somatostatin analog on gallium-68 DOTATATE imaging quality needs to be evaluated. A single institution retrospective review of the first 200 NET patients with gallium-68 DOTATATE imaging from Dec 2016 to Dec 2017 was conducted. Questions related to NETs of unknown primary, correlation of Standardized Uptake Value (SUV) to Ki-67 (which signifies proliferation rate), the effects of long-acting systemic somatostatin analog (SSA) on SUV were part of our data analysis. From these 200 patients, 59.5% (119) were females, 40.5% (81) were males; the median age was 62 years. The following primary tumor sites were identified: small bowel-37.5%; pancreas-18.5%; bronchial-14%; colon-3.5%; rectum-2%; appendix-1.5%; adrenal-0.5%; prostate-0.5%; others-3% and unknown primary-19%. Mean hepatic SUV of the lesion with the greatest radiolabeled uptake in 96 patients was similar irrespective to exposure to long acting SSA. Patients exposed to long acting SSA had mean SUV of 31.3 vs 27.8 for SSA naïve patients. The difference was not statistically significant. Gallium-68 DOTATATE imaging seems to distinguished G3 NET from G1/G2 based on mean SUV, and also identified the primary tumor site in 17 of 38 (45%) patients with unknown primary. Systemic exposure to long acting SSA does not appear to influence mean SUV of gallium-68 DOTATATE scan.

Brain Metastasis From Bartholin Gland Carcinoma

BACKGROUND

Small cell neuroendocrine carcinoma of the Bartholin gland is an extremely uncommon gynecologic tumor. Brain metastasis from a malignant gynecologic lesion is rarely encountered and the prognosis for this type of metastasis is quite poor.

CASE DESCRIPTION

We report a case of a brain metastasis from a small cell neuroendocrine carcinoma of the Bartholin gland that was treated by surgical resection followed by whole-brain radiation therapy and review the literature.

CONCLUSIONS

Different treatment options, including resection, stereotactic radiosurgery, and whole-brain radiation therapy, as well as chemotherapy, are available and should each be considered on an individual basis.

Preoperative systemic immune-inflammation index and prognostic nutritional index predict prognosis of patients with pulmonary neuroendocrine tumors after surgical resection

Background

Pulmonary neuroendocrine tumors (PNETs) are a special subtype of lung cancer with treatment methods are limited and prognostic indicators are insufficient. The preoperative systemic immune-inflammation index (SII) and prognostic nutritional index (PNI) are effective tumor biomarkers that have important significance for the prognosis of many malignant tumors. However, there is no similar research on the predictive value of SII and PNI for operable PNETs. Our study aimed to clarify the predictive value of SII and PNI in PNETs patients after surgical resection.

Methods

This study retrospectively analysed the relevant clinical data of PNETs patients who received surgical treatment from 2005 to 2015, which was obtained from patient's clinical records, blood test results recorded on admission before surgical treatment, and follow-up by hospital records.

Results

A total of 381 PNETs patients were enrolled in this study. Preoperative PNI was associated with age (P=0.001), T stage (P=0.001), tumor length (P=0.002), drinking status (P=0.013) and smoking status (P=0.049), while SII was significantly associated with T stage (P=0.001), tumor length (P=0.001) and TNM stage (P=0.001). There was significant difference between high SII and low PNI and worse OS of PENTs (P=0.001 and P<0.001). SII (P=0.002), neutrophil/lymphocyte ratio (NLR) (P<0.001), platelet/lymphocyte ratio (PLR) (P=0.001), lymph node metastasis (P<0.001), operation time (P=0.034<0.05), treatment (P<0.001) and PNI (P=0.044<0.05) were independent prognostic factors for PNETs identified by multivariate Cox regression analysis.

Conclusions

High SII and low PNI indicated poor prognosis of patients with PNETs. Both of SII and PNI can predict the prognosis of PNETs and stratify patients for better treatment.

Diagnostic imaging of typical lung carcinoids: relationship between MDCT, 111In-Octreoscan and 18F-FDG-PET imaging features with Ki-67 index

AIMS

This study analyses the capability of contrast-enhanced multi-detector computed tomography (MDCT) and spectrum of molecular imaging to characterize typical carcinoids (TCs) of lung and their relationship with Ki-67 index.

MATERIALS AND METHODS

We analysed 68 patients with histological diagnosis of pulmonary TC, which underwent both MDCT and nuclear molecular imaging (somatostatin receptor scintigraphy/SPECT with ¹¹¹In-pentetreotide and ¹⁸F-FDG-PET/CT) at staging evaluation before surgery. The MDCT scan was reviewed for the following features: size, margins, contrast enhancement, presence of calcifications, bronchial obstruction, lymph nodes and metastases. In ¹¹¹In-pentetreotide SPECT, tumour/non-tumour ratio was measured at 4- and 24-h post-injection and the per cent difference was calculated (T/NT%). FDG uptake was measured as the ratio between lesion SUVmax and liver SUVmean (SUV ratio). All imaging features were correlated between them and with Ki-67 index.

RESULTS

Forty-four of the 68 lesions (65%) were in the right lung. In MDCT, scan lesions appeared as a well-defined nodule in 44 patients (65%) and irregular mass in 24 patients (35%). Contrast intense enhancement was present in 53 patients (78%), calcifications in 20 patients (29%) and bronchial obstruction in 24 patients (35%). Lymph nodes and metastasis were present in 13 (19%) and 15 (22%) patients. Ki-67 index was negatively correlated with T/NT% and positively with SUV ratio; T/NT% and SUV ratio were inversely correlated. The presence of irregular margins and metastases was negatively related to T/NT%. The presence of a mass, irregular margins, bronchial obstruction, lymph nodes and metastasis was positively related to higher SUV ratio. The presence of irregular margins, bronchial obstruction, lymph nodes and metastases was significantly correlated with a higher grade of Ki-67 index.

CONCLUSIONS

MDCT and nuclear molecular imaging are important to characterize lung TCs. The majority of TCs appear as a well-defined nodule generally not associated with extra-thorax signs. We found a significant correlation between some MDCT aspects, nuclear medicine features and Ki-67 index. The association of MDCT and nuclear medicine imaging may be useful in predicting proliferative activity and prognosis of lung TCs.

99mTc-EDDA/HYNIC-TOC is a New Opportunity in Neuroendocrine Tumors of the Lung (and in other Malignant and Benign Pulmonary Diseases)

Neuroendocrine tumors (NETs) consist of a relatively rare spectrum of malignancies that can arise from neuroendocrine cells; lung NETs (L-NETs) represent about 25% of primary lung neoplasm and 10% of all carcinoid tumors. Diagnostic algorithm usually takes into consideration chest Xray, contrast-enhanced CT and MRI. Nuclear medicine plays a crucial role in the detection and correct assessment of neoplastic functional status as it provides in vivo metabolic data related to the overexpression of Somatostatin Receptors (SSTRs) and also predicting response to peptide receptor radionuclide therapy (PRRT). 111In-Pentreotide (Octreoscan®) is commercially available for imaging of neuroendocrine tumors, their metastases and the management of patients with NETs. More recently, 99mTc-EDDA/HYNIC-TOC(Tektrotyd®) was introduced into the market and its use has been approved for imaging of patients with L-NETs and other SSTR-positive tumors. 99mTc-EDDA/HYNIC-TOC could also represent a good alternative to 68Ga-DOTA-peptides (DOTA-TOC, DOTA-NOC, DOTATATE) in hospitals or centers where PET/CT or 68Ge/68Ga generators are not available. When compared to 111In-Pentetreotide, Tektrotyd® showed slightly higher sensitivity, in the presence of higher imaging quality and lower radiation exposure for patients. Interesting perspectives depending on the kinetic analysis allowed by Tektrotyd® may be obtained in differential diagnosis of non-small cells lung cancer (NSCLC) versus small cells lung cancer (SCLC) and NETs. An interesting perspective could be also associated with a surgery radio-guided by Tektrotyd® in operable lung tumors, including either NETs and NSCLC.

Treatment of atypical pulmonary carcinoid with combination ipilimumab and nivolumab

Atypical pulmonary carcinoid (APC) is a lung neuroendocrine neoplasm (NEN), whose treatment draws from management of gastrointestinal NENs and small-cell lung carcinoma. We present a patient with recurrent metastatic APC and persistent mediastinal lymphadenopathy refractory to cisplatin and etoposide. After pursuing alternative treatments, he returned with significant progression, including diffuse subcutaneous nodules, weight loss and worsening cough. New biopsy analysis demonstrated APC with low mutational burden, low Ki-67 and Programmed Death-Ligand 1 (PD-L1), and without microsatellite instability. We pursued combination nivolumab and ipilimumab treatment based on success of CheckMate 032 in small-cell lung cancer. The patient's symptoms dramatically responded within a month, with almost complete resolution of lymphadenopathy following four cycles. He has been successfully maintained on nivolumab for the last 18 months. This suggests combination immunotherapy may be beneficial in the treatment of metastatic APC, and that PD-L1 and cytotoxic T-lymphocyte-associated protein 4 (CTLA-4) inhibitors may be valuable in treating tumours lacking traditional biomarkers.

Large Cell Neuroendocrine Tumor Size >3 cm Negatively Impacts Long-Term Outcomes After R0 Resection

BACKGROUND

Minimal knowledge exists regarding the outcome, prognosis and optimal treatment strategy for patients with pulmonary large cell neuroendocrine carcinomas (LCNEC) due to their rarity. We aimed to identify factors affecting survival and recurrence after resection to inform current treatment strategies.

METHODS

We retrospectively reviewed 72 patients who had undergone a curative resection for LCNEC in 8 centers between 2000 and 2015. Univariable and multivariable analyses were performed to identify the factors influencing recurrence, disease-specific survival and overall survival. These included age, gender, previous malignancy, ECOG performance status, symptoms at diagnosis, extent of resection, extent of lymphadenectomy, additional chemo- and/or radiotherapy, tumor location, tumor size, pT, pleural invasion, pN and pStage.

RESULTS

Median follow-up was 47 (95%CI 41-79) months; 5-year disease-specific and overall survival rates were 57.6% (95%CI 41.3-70.9) and 47.4% (95%CI 32.3-61.1). There were 22 systemic recurrences and 12 loco-regional recurrences. Tumor size was an independent prognostic factor for systemic recurrence [HR: 1.20 (95%CI 1.01-1.41); p = 0.03] with a threshold value of 3 cm (AUC = 0.71). For tumors ≤3 cm and >3 cm, 5-year freedom from systemic recurrence was 79.2% (95%CI 43.6-93.6) and 38.2% (95%CI 20.6-55.6) (p < 0.001) and 5-year disease-specific survival was 60.7% (95%CI 35.1-78.8) and 54.2% (95%CI 32.6-71.6) (p = 0.31), respectively.

CONCLUSIONS

A large proportion of patients with surgically resected LCNEC will develop systemic recurrence after resection. Patients with tumors >3 cm have a significantly higher rate of systemic recurrence suggesting that adjuvant chemotherapy should be considered after complete resection of LCNEC >3 cm, even in the absence of nodal involvement.

Double-edged role of radiotherapy in patients with pulmonary large-cell neuroendocrine carcinoma

Purpose: Pulmonary large-cell neuroendocrine carcinoma (LCNEC) is classified as non-small-cell lung cancer, but has characteristics similar to small-cell lung cancer. This study was performed to evaluate the effect of surgery and radiotherapy on patients with LCNEC.

Materials and Methods: We analyzed 1,619 patients with stage I-III LCNEC, identified from the Surveillance, Epidemiology, and End Results database, diagnosed from 2000 to 2013. The Kaplan-Meier analysis and the Cox proportional hazard model were used to study patient prognosis.

Results: Overall, 869 (53.7%) stage I LCNEC patients, 203 (12.5%) stage II patients, and 547 (33.8%) stage III patients were included in the analysis. Various surgery types were all associated with higher overall survival (OS) and lung cancer-specific survival (LCSS) than no surgery, with the following HRs: 0.334 (OS) and 0.279 (LCSS) for lobectomy, 0.468 (OS) and 0.416 (LCSS) for partial/wedge/segmental resection, and 0.593 (OS) and 0.522 (LCSS) for pneumonectomy (all p < 0.05). OS and LCSS of stage I and II LCNEC patients were not improved by radiotherapy (stage I: OS p = 0.719, LCSS p = 0.557; stage II: OS p = 0.136, LCSS p = 0.697). However, in stage III patients, radiotherapy significantly improved both OS and LCSS (p < 0.001). Following multivariate analysis, increased age, male patients, radiotherapy and diagnosed at stage II or III were all independent risk factors for LCNEC (all p < 0.05).

Conclusion: Lobectomy had the best outcome for OS and LCSS in stage I-II LCNEC. For stage III LCNEC patients, radiotherapy can significantly improve survival time. However, in LCNEC patients undergoing surgery, radiotherapy may reduce survival time.

Wedge resection is equal to segmental resection for pulmonary typical carcinoid patients at localized stage: a population-based analysis

Background

Medical institutions worldwide have not reached a consensus on what surgery is the most advisable for pulmonary typical carcinoid (TC) patients at the localized stage. This research focuses on exploring whether wedge resection or segmental resection is the superior option.

Methods

The demographic and clinical information of 1,887 TC patients diagnosed at the localized stage from 2004 to 2015 was collected from the Surveillance, Epidemiology, and End Results (SEER) Program. Patient prognosis was evaluated by KM curves. The chi-square test was used to examine the variation between different groups that would be eliminated by propensity score matching (PSM). Univariate and multivariate Cox proportional hazard model analyses were used to evaluate prognostic values of relative factors.

Results

The prognosis of TC was the most favorable for patients suffering from pulmonary squamous cell carcinoma (SCC), adenocarcinoma (ADC), and pulmonary carcinoids (PCs). The choice to have surgery, not the type of surgery chosen, was the most significant independent prognostic factor correlated with overall survival (OS) and lung cancer-special survival (LCSS). The prognostic result of the comparison between wedge resection and segmental resection was not statistically significant before or after PSM. In subgroup analysis, the inference still held.

Peptide Receptor Radionuclide Therapy for Patients With Advanced Lung Carcinoids

Neuroendocrine neoplasms (NEN) are a family of malignancies of diverse origin, including the lung, gastrointestinal tract, and pancreas. Lung NEN include well differentiated neuroendocrine tumors (NET) classified as typical carcinoids or atypical carcinoids, and poorly differentiated neuroendocrine carcinomas classified as small-cell lung carcinoma or large-cell neuroendocrine carcinoma. According to a recent analysis of a large, population-based registry, approximately one-third of all patients with lung typical/atypical carcinoids have distant metastases at diagnosis, and median survival for these patients is 24 months. At present, only 1 therapy is approved by the US Food and Drug Administration (FDA) for patients with advanced lung typical/atypical carcinoids, everolimus, indicating a clear need for more treatment options in this patient population. Although not yet supported by results from randomized prospective trials, somatostatin analogues are considered an acceptable treatment option for patients with lung typical/atypical carcinoids expressing somatostatin receptors. Peptide receptor radionuclide therapy (PRRT) with ¹⁷⁷Lu-DOTATATE was recently approved by the FDA for the treatment of gastroenteropancreatic NET; however, the role of PRRT in patients with lung typical/atypical carcinoids remains unclear, because they were not included in the pivotal NETTER-1 (Neuroendocrine Tumors Therapy) trial. Herein we provide a comprehensive review of the available clinical evidence for efficacy and safety of PRRT in patients with lung typical/atypical carcinoids. On the basis of the preliminary evidence of efficacy and the consistent safety profile in this patient group, we propose that experienced multidisciplinary NET teams may consider PRRT alongside everolimus as an option for patients with advanced somatostatin receptor-positive lung typical/atypical carcinoids whose disease is progressing during first-line treatment with somatostatin analogues.

Primary small cell neuroendocrine carcinoma of the Bartholin's gland: A case report

Primary carcinoma of the Bartholin's gland (BG) is a rare malignancy. There are extremely rare cases of small cell neuroendocrine carcinoma (SCNC) of the BG reported in the English literature. A postmenopausal female presented with a 1-month history of increasing pain and swelling on the left vulva consistent with spontaneously bleeding. Pathology identified SCNC that arose in BG. The patient was treated with a radical wide local excision and bilateral inguinal lymph node dissection followed by six courses of chemotherapy. One month after primary treatment, without any pelvic recurrence or abnormal tumor markers indications, distant metastasis of the liver was diagnosed and VI hepatic lobectomy was performed. The patient maintained regular adjuvant chemotherapy every month under outpatient surveillance and has no local recurrence or distant metastasis.

Multilayered heterogeneity as an intrinsic hallmark of neuroendocrine tumors

Neuroendocrine tumors (NETs) comprise a complex and highly heterogeneous group of neoplasms that can arise all over the body, originating from neuroendocrine cells. NETs are characterized by a general lack of symptoms until they are in advanced phase, and early biomarkers are not as available and useful as required. Heterogeneity is an intrinsic, pivotal feature of NETs that derives from diverse causes and ultimately shapes tumor fate. The different layers that conform NET heterogeneity include a wide range of distinct characteristics, from the mere location of the tumor to its clinical and functional features, and from its cellular properties, to the core signaling and (epi)genetic components defining the molecular signature of the tumor. The importance of this heterogeneity resides in that it translates into a high variability among tumors and, hence, patients, which hinders a more precise diagnosis and prognosis and more efficacious treatment of these diseases. In this review, we highlight the significance of this heterogeneity as an intrinsic hallmark of NETs, its repercussion on clinical approaches and tumor management, and some of the possible factors associated to such heterogeneity, including epigenetic and genetic elements, post-transcriptional regulation, or splicing alterations. Notwithstanding, heterogeneity can also represent a valuable and actionable feature, towards improving medical approaches based on personalized medicine. We conclude that NETs can no longer be viewed as a single disease entity and that their diagnosis, prognosis and treatment must reflect and incorporate this heterogeneity.

Assessment of the prognostic factors in patients with pulmonary carcinoid tumor: a population-based study

Previous studies have identified potential risk factors for pulmonary carcinoid tumors and evaluated the effect of various treatments; however, the results were not entirely consistent. We conducted a population‐based study to further explore relevant prognostic issues. We extracted cases with pulmonary carcinoid tumors from the Surveillance Epidemiology and End Results database. Cox proportional hazard regression was utilized to identify potential significant risk factors, which helped establish a nomogram for predicting long‐term survival. Survival analysis and a competing risk study were conducted to evaluate the value of different surgical approaches. There were 7057 cases included in the study. Univariate and multivariate analyses showed that age, sex, tumor size, stage, histology, surgical type, chemotherapy, and radiation therapy were all significant prognostic factors. A nomogram with good accuracy for predicting 10‐year survival was formulated. Furthermore, patients who had undergone surgery had a significantly better survival than those who did not undergo surgery. There was no significant prognostic difference between lobectomy and sublobectomy stratified by tumor stage; however, lobectomy was associated with a significantly better survival in atypical tumors, especially those with regional disease. Our research identified possible risk factors in a large cohort and constructed a nomogram to visually predict 10‐year survival of pulmonary carcinoid tumors. We showed that lobectomy and sublobectomy should be considered as the mainstay of treatment, especially lobectomies for atypical tumor.