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

Relation between WHO Classification and Location- and Functionality-Based Classifications of Neuroendocrine Neoplasms of the Digestive Tract

Practice of neuroendocrine neoplasms (NENs) of the digestive tract, which comprise of a highly diverse group of tumors with a rising incidence, faces multiple biological, diagnostic, and therapeutic issues. Part of these issues is due to misuse and misinterpretation of the classification and terminology of NENs of the digestive tract, which make it increasingly challenging to evaluate and compare the literature. For instance, grade 3 neuroendocrine tumors (NETs) are frequently referred to as neuroendocrine carcinomas (NECs) and vice versa, while NECs are, by definition, high grade and therefore constitute a separate entity from NETs. Moreover, the term NET is regularly misused to describe NENs in general, and NETs are frequently referred to as benign, while they should always be considered malignancies as they do have metastatic potential. To prevent misconceptions in future NEN-related research, we reviewed the most recent terminology used to classify NENs of the digestive tract and created an overview that combines the classification of these NENs according to the World Health Organization (WHO) with location- and functionality-based classifications. This overview may help clinicians and researchers in understanding the current literature and could serve as a guide in the clinic as well as for writing future studies on NENs of the digestive tract. In this way, we aim for the universal use of terminology, thereby providing an efficient foundation for future NEN-related research.

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.

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.

A multidisciplinary approach to the work up and management of pulmonary carcinoid tumors and DIPNECH: a narrative review

Background and Objective

Low and intermediate grade neuroendocrine tumors of the lung are uncommon malignancies representing 2% of all lung cancers. These are termed typical and atypical pulmonary carcinoid tumors. These can arise in the setting of diffuse idiopathic pulmonary neuroendocrine cell hyperplasia (DIPNECH). The presentation, workup, management and outcomes of patients with these tumors can overlap with more common lung cancers but differ in that many of these patients have a prolonged clinical course. The objective of this narrative review is to summarize the literature and provide evidence and expert-based algorithms for work up and treatment of pulmonary carcinoids and DIPNECH.

Methods

A search of PubMed and Web of Science databases ending April 15, 2022, with the following keywords "lung carcinoid", "DIPNECH", "lung neuroendocrine," and "bronchopulmonary carcinoid".

Key Content and Findings

Pulmonary carcinoid tumors benefit from a multidisciplinary approach. Pre-treatment imaging with contrast-enhanced computed tomography, and DOTATATE positron emission tomography is required. Surgical resection is the gold standard for curative intent, and possibly including sublobar resections. Patients can recur or develop new primaries thus emphasizing the importance of surveillance; national guidelines recommend at least a 10-year follow up. A growing body of literature support the use of endobronchial therapy, with long responses documented. Systemic therapy consists of everolimus, somatostatin analogs, peptide receptor radionuclide therapy, and chemotherapy. Diffuse idiopathic pulmonary neuroendocrine tumor cell hyperplasia is rare, but series suggest somatostatin analogs may confer clinical benefit.

Conclusions

Pulmonary carcinoid tumors and DIPNECH are rare. Despite lack of regulatory approvals for advanced disease, multiple options are available but should be sequenced according to the clinical status and disease biology. Each patient should be discussed in a multidisciplinary setting and clinical trials should be considered if available.

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.

Long-term survival analysis of sublobar resection versus lobectomy for older patients with early-stage pulmonary carcinoid tumour: a database-based propensity score-matched study

BACKGROUND

The optimal extent of surgery for older patients with early-stage pulmonary carcinoid tumour (PC) remains controversial.

AIMS

To compare prognostic differences between sublobar resection versus lobectomy in older patients with early-stage PC.

METHODS

The SEER database was searched for stage T1N0M0 PC patients aged ≥ 65 years who underwent lobectomy or sublobar resection from 2000 to 2017. Propensity score matching (PSM) was used to determine intergroup covariate differences. Kaplan-Meier curves and the log-rank test were used for intergroup comparison of overall survival (OS). A Cox proportional hazard model was used to evaluate independent risk factors.

RESULTS

Among 1023 participants, 650 and 373 underwent lobectomy and sublobar resection, respectively. Before PSM, the 5- and 10-year OS in the sublobar resection group were lower than that of the lobectomy group (5-year OS 84.12% vs. 91.16%; 10-year OS 57.43% vs. 64.77%; p = 0.014); after PSM, no significant prognostic difference existed between lobectomy and sublobar resection (5-year OS 88.17% vs. 89.23%; 10-year OS 58.32% vs. 62.75%; p = 0.811). Subgroup analysis included tumour size, age, number of lymph nodes examined and histological type, and showed no statistically significant survival differences between the lobectomy and sublobar resection groups. Multivariable Cox analysis indicated that age ≥ 77 years, male sex, inadequate lymph node assessment (< 7), and atypical carcinoid were associated with reduced OS.

CONCLUSION

Sublobar resection showed a similar long-term survival rate for early-stage PC patients aged ≥ 65 years as with lobectomy, thereby providing a basis for the selection of surgical methods for PC.

Treatment of Pulmonary Carcinoid Tumors With Bronchoscopic Cryotherapy: A 28-Year Single-center Experience

BACKGROUND

Pulmonary carcinoids are rare tumors originating from neuroendocrine cells in the lungs. Because of their potentially infiltrative nature, surgical resection remains the treatment of choice. However, not all patients with technically resectable disease will be able to undergo surgery, primarily because of poor lung function or medical co-morbidities. Centrally located, intraluminal tumors have been reported to be amenable to bronchoscopic treatment. We specifically examined the role of cryotherapy in the treatment of bronchial carcinoid tumors.

METHODS

Sixty-three patients (52.38% female) who underwent a combined total of 243 cryotherapy procedures for treatment of bronchial carcinoid between 1992 and 2020 in our institution were included in the study. Following discussion in multidisciplinary meetings, patients were considered for first-line cryotherapy when lung resection was deemed not possible or when they had rejected surgery.

RESULTS

Cryotherapy resulted in complete remission in 21 (33.33%) patients with maximum tumor diameter less than 20 mm (mean: 11.08 mm, 95% confidence interval: 8.76-13.40), and allowed 22 (34.92%) patients with larger lesions (mean: 24.04 mm, 95% confidence interval: 18.78-29.30) to proceed with parenchymal sparing resections. Marked symptomatic relief (P<0.001) was reported by 58 (92.06%) patients. The median follow-up was 33 months (range: 0 to 243 mo). One (1.59%) patient was diagnosed with recurrence in a contralateral lobe 3 years after surgery and was treated with radiofrequency ablation.

CONCLUSIONS

In the absence of a definitive randomized controlled trial comparing bronchoscopic treatment with surgical resection, we provide evidence on the safety and efficacy of cryotherapy and encourage wider adoption of this inexpensive and minimally invasive technique for treatment of bronchial carcinoids.

Curative lobectomy without a preoperative tissue diagnosis in a tuberculosis endemic country: A case report and discussion

Curative surgery for a localized tumour at the early and pre-symptomatic stage is the main aim of lung nodule assessment. As part of the process, pre-operative tissue diagnosis is a key step in making appropriate clinical decisions and avoiding unnecessary invasive surgical intervention which is associated with high morbidity. In this case report, we describe a patient who had a curative lobectomy for a growing nodule without a preoperative tissue diagnosis although the initial discussion deemed it mandatory, and we dissected the arguments supporting it in the setting of a tuberculosis endemic country.

The Correlation of the Neutrophil-Lymphocyte Ratio and the Platelet-Lymphocyte Ratio With Pathological Findings in Neuroendocrine Tumors

Introduction The relationship between clinical prognostic factors and blood neutrophil-lymphocyte ratio (NLR) and platelet-lymphocyte ratio (PLR) in some tumors has been investigated. In this study, we examined whether there is a relationship between pathological prognostic factors and NLR as well as PLR only in neuroendocrine tumors (NETs). Methods A total of 115 patients with a NET diagnosis between 2014-2020 were included in the study. The efficiency of NLR and PLR in predicting distant metastases was determined by analyzing the receiver operating characteristic (ROC) curve. The relationship between histopathological parameters was also compared. Results The cut-off value of NLR was 3.01 for predicting distant metastasis. At this value, the specificity was 73.7%, the sensitivity was 70.7%, and the likelihood ratio was 2.51. There was a significant relationship between NLR and tumor localization, histological grade, mitosis, Ki-67, distant metastasis, and lymphovascular invasion (all p<0.001). The cut-off value of the PLR in predicting distant metastasis was 134.4. At this value, the specificity was 59.6%, the sensitivity was 58.6%, and the likelihood ratio was 1.44. There was no significant relationship between PLR and the histopathological findings (all p>0.05). Conclusions In our study, a high histological grade, high mitosis, a high Ki-67 proliferation index, distant metastasis, and lymphovascular invasion were found in patients with NLR at a cut-off value above 3.01. However, we could not attain the same results for PLR. For trucut and endoscopic biopsies in particular, follow-up of patients with grades 1 and 2 NETs along with histopathological findings and evaluation of NLR in peripheral blood may be useful. NLR, which is an easily accessible inflammatory marker, can be used as an independent predictive factor in NETs.

Bronchial carcinoid tumor managed with bronchial artery embolization before endobronchial resection: A case report

Endobronchial resection using a bronchoscope is often selected as treatment for carcinoid tumors located in the central airways. However, massive bleeding is one of the most serious complications during bronchoscopic surgery. Here, we report the case of a 77‐year‐old female with a typical carcinoid tumor located in the right truncus intermedius who underwent bronchial artery embolization (BAE) one day before endobronchial intervention using a flexible bronchoscope. The tumor was successfully resected without bleeding. BAE prior to endobronchial resection of carcinoid tumors may be useful for reducing the risk of bleeding.

A miR-375/YAP axis regulates neuroendocrine differentiation and tumorigenesis in lung carcinoid cells

Lung carcinoids are variably aggressive and mechanistically understudied neuroendocrine neoplasms (NENs). Here, we identified and elucidated the function of a miR-375/yes-associated protein (YAP) axis in lung carcinoid (H727) cells. miR-375 and YAP are respectively high and low expressed in wild-type H727 cells. Following lentiviral CRISPR/Cas9-mediated miR-375 depletion, we identified distinct transcriptomic changes including dramatic YAP upregulation. We also observed a significant decrease in neuroendocrine differentiation and substantial reductions in cell proliferation, transformation, and tumor growth in cell culture and xenograft mouse disease models. Similarly, YAP overexpression resulted in distinct and partially overlapping transcriptomic changes, phenocopying the effects of miR-375 depletion in the same models as above. Transient YAP knockdown in miR-375-depleted cells reversed the effects of miR-375 on neuroendocrine differentiation and cell proliferation. Pathways analysis and confirmatory real-time PCR studies of shared dysregulated target genes indicate that this axis controls neuroendocrine related functions such as neural differentiation, exocytosis, and secretion. Taken together, we provide compelling evidence that a miR-375/YAP axis is a critical mediator of neuroendocrine differentiation and tumorigenesis in lung carcinoid cells.

Diagnostic Value of Conventional PET Parameters and Radiomic Features Extracted from 18F-FDG-PET/CT for Histologic Subtype Classification and Characterization of Lung Neuroendocrine Neoplasms

Aim: To evaluate if conventional Positron emission tomography (PET) parameters and radiomic features (RFs) extracted by 18F-FDG-PET/CT can differentiate among different histological subtypes of lung neuroendocrine neoplasms (Lu-NENs). Methods: Forty-four naïve-treatment patients on whom 18F-FDG-PET/CT was performed for histologically confirmed Lu-NEN (n = 46) were retrospectively included. Manual segmentation was performed by two operators allowing for extraction of four conventional PET parameters (SUVmax, SUVmean, metabolic tumor volume (MTV), and total lesion glycolysis (TLG)) and 41 RFs. Lu-NENs were classified into two groups: lung neuroendocrine tumors (Lu-NETs) vs. lung neuroendocrine carcinomas (Lu-NECs). Lu-NETs were classified according to histological subtypes (typical (TC)/atypical carcinoid (AC)), Ki67-level, and TNM staging. The least absolute shrink age and selection operator (LASSO) method was used to select the most predictive RFs for classification and Pearson correlation analysis was performed between conventional PET parameters and selected RFs. Results: PET parameters, in particular, SUVmax (area under the curve (AUC) = 0.91; cut-off = 5.16) were higher in Lu-NECs vs. Lu-NETs (p < 0.001). Among RFs, HISTO_Entropy_log10 was the most predictive (AUC = 0.90), but correlated with SUVmax/SUVmean (r = 0.95/r = 0.94, respectively). No statistical differences were found between conventional PET parameters and RFs (p > 0.05) and TC vs. AC classification. Conventional PET parameters were correlated with N+ status in Lu-NETs. Conclusion: In our study, conventional PET parameters were able to distinguish Lu-NECs from Lu-NETs, but not TC from AC. RFs did not provide additional information.

IGF1R and MAPK15 Emerge as Potential Targets of Pentabromobenzylisothioureas in Lung Neuroendocrine Neoplasms

Pentabromobenzylisothioureas are antitumor agents with diverse properties, including the inhibition of MAPK15, IGF1R and PKD1 kinases. Their dysregulation has been implicated in the pathogenesis of several cancers, including bronchopulmonary neuroendocrine neoplasms (BP-NEN). The present study assesses the antitumor potential of ZKKs, a series of pentabromobenzylisothioureas, on the growth of the lung carcinoid H727 cell line. It also evaluates the expression of MAPK15, IGF1R and PKD1 kinases in different BP-NENs. The viability of the H727 cell line was assessed by colorimetric MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl-tetrazolium bromide) and its proliferation by BrdU (5-bromo-2′-deoxyuridine) assay. Tissue kinase expression was measured using TaqMan-based RT-PCR and immunohistochemistry. ZKKs (10⁻⁴ to 10⁻⁵ M) strongly inhibited H727 cell viability and proliferation and their antineoplastic effects correlated with their concentrations (p < 0.001). IGF1R and MAPK15 were expressed at high levels in all subtypes of BP-NENs. In addition, the SCLC (small cell lung carcinoma) patients demonstrated higher mRNA levels of IGF1R (p = 0.010) and MAPK15 (p = 0.040) than the other BP-NEN groups. BP-NENs were characterized by low PKD1 expression, and lung neuroendocrine cancers demonstrated lower PKD1 mRNA levels than carcinoids (p = 0.003). ZKKs may suppress BP-NEN growth by inhibiting protein kinase activity. Our results suggest also a possible link between high IGF1R and MAPK15 expression and the aggressive phenotype of BP-NEN tumors.

Multimodality Imaging of Neuroendocrine Tumors

Neuroendocrine tumors are rare solid tumors with an estimated 12,000 people in the United States diagnosed each year. Neuroendocrine tumors can occur in any part of the body. There is a wide spectrum of disease, ranging from slow-growing and indolent tumors found incidentally to highly aggressive malignancies with a poor prognosis. Knowledge of neuroendocrine tumor pathology is essential in the diagnostic workup of these patients. This article focuses on the evaluation, detection, and staging of common neuroendocrine tumors with multiple imaging modalities; the information gained with a multimodality approach is often complementary and leads to image-guided treatment decision making.

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.

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.

Metastatic small cell neuroendocrine carcinoma of the submandibular gland from the lung: A case report

RATIONALE

Small cell neuroendocrine carcinoma of the salivary gland is an extremely rare condition. To the best of our knowledge, metastasis of small cell neuroendocrine lung cancer to the submandibular gland has not been reported in the literature.

PATIENT CONCERN

An 87-year-old female complained of a left neck mass that enlarged from one month ago.

DIAGNOSIS

The final diagnosis was diagnosed as a metastatic small cell neuroendocrine carcinoma of the submandibular gland from lung by an immunohistochemistry.

INTERVENTIONS

Left submandibular resection was performed under general anesthesia.

OUTCOMES

We recommended further evaluation and treatment, but the patient and patient family support team rejected further treatment of her condition. It was confirmed that 3 months after this conclusive diagnosis, the patient died as a result of this condition and disease.

LESSONS

Small cell neuroendocrine carcinoma of the salivary gland is an extremely rare condition. We report a case of metastatic small cell neuroendocrine carcinoma of the submandibular gland from the lung.

Diagnostic and Management Pathways for Pulmonary Carcinoid Tumours in the United Kingdom: Results from the National Lung Neuroendocrine Tumour Pathway Project

There is inconsistency among published guidelines for the optimal diagnostic and management pathways for patients with typical (TC) or atypical (AC) pulmonary carcinoid tumours. We conducted a UK-wide clinician survey to assess current practice for the diagnosis, management, and follow-up of patients with TC/AC and descriptively compared management between European Neuroendocrine Tumor Society (ENETS) accredited centres of excellence (CoE) and nonaccredited centres (non-CoE). Twenty-seven clinicians (10 CoE; 17 non-CoE) participated. Computed tomography of thorax, abdomen, and pelvis was the most commonly reported diagnostic tool (96% of respondents), and bone scans and gallium somatostatin receptor scintigraphy positron emission tomography (SRS PET) were the least commonly reported (30% and 37% of respondents, respectively). Adjuvant therapy is considered for resected TC/AC by <5% of respondents for patients with stage N0 M0 AC or TC, up to 48% of respondents for patients with AC with R1 disease. Somatostatin analogues were the most commonly reported first-line treatment (63% of respondents), and chemotherapy was the most commonly reported second-line therapy and third-line therapy (33% and 41%, respectively) for unresectable and metastatic disease. Reported frequency of initial follow-up after primary surgery ranged from every 2 months to annual, and total follow-up duration ranged from 2 years to indefinite depending on disease type (TC/AC) and stage. For most diagnostic investigations, the highest reported frequency of use was in CoE, most notably gallium SRS PET (70% CoE vs. 18% non-CoE respondents). 93% of respondents (100% CoE; 88% non-CoE) reported having neuroendocrine tumour- (NET-) specialist multidisciplinary team meetings at their centre; 59% (90% CoE; 41% non-CoE) had a NET Clinical Nurse Specialist (CNS) and 48% (80% CoE; 29% non-CoE) had a lung NET patient database. The survey results suggest variability between UK centres in diagnostic pathways and management of patients with TC/AC and suggest that CoE may be able to offer an improved service to patients.

Predictive Value of 99MTC-hynic-toc Scintigraphy in Lung Neuroendocrine Tumor Diagnosis

Background:

Νeuroendocrine tumors of the lungs are rare arising in the thymus and gastro-entero-pancreatic tract and belonging to foregut of neuroendocrine tumors. The aim of the present prospective study was to estimate the potential impact of single-photon emission computed tomography somatostatin receptor scintigraphy using 99mTc-Tektrotyd on diagnosis, treatment response, and prognosis in patients with neuroendocrine tumors of the lungs.

Methods:

Thirty-six patients with neuroendocrine tumors of the lungs were evaluated by using 99mTc-HYNIC-TOC scintigraphy. The scintigraphic results were compared to liver tissue uptake (Krenning score). Likewise, the functional imaging results were compared with biochemical indices including chromogranin A, neuroendocrine-specific enolase, and insulin-like growth factor 1 at the time of diagnosis (baseline) and disease progression.

Results:

The number of somatostatin receptors, expressed with Krenning score, did not show any correlation with the survival of patients both at baseline (P = .08) and at disease progression (P = .24), and scintigraphy results did not relate significantly to progression-free survival. Comparing the results of 99mTc-HYNIC-TOC scintigraphy according to the response of patients in the initial treatment, a statistically significant negative correlation was observed both in the first and in the second scintigraphy with patients’ response (P = .001 and P < .001, respectively). The concentrations of biochemical markers were in accordance with scintigraphy results in the diagnosis.

Conclusion:

This study indicates that 99mTc-HYNIC-TOC scintigraphy appears to be a reliable, noninvasive technique for detection of primary neuroendocrine tumors and their locoregional or distant metastases, although it cannot be used as a neuroendocrine tumors of the lungs predictive technique.

[Surgical Resection and Prognosis of Bronchopulmonary Carcinoid]

BACKGROUND

Bronchopulmonary carcinoid (BPC) is a rare neuroendocrine tumor, the clinical studies on treatment and prognostic factors of BPC are somewhat controversial. Our purpose was to evaluate the clinical efficacy of surgery on BPC, and to analyze the prognostic factors affecting the survival of BPC.

METHODS

We retrospectively collected the clinical data of patients with BPC admitted to the Chinese PLA General Hospital between January 2000 and December 2017. The Kaplan-Meier method was used to calculate the survival rate of patients and to map the survival curve. Then the effects of different factors like pathological classification, gender, age, on prognosis were compared by univariate analysis and multivariate analysis was made by Cox proportional hazard model.

RESULTS

A total of 98 patients had a diagnosis of BPC were included in the study. There were 41 patients with typical carcinoid (TC) and 57 patients with atypical carcinoid (AC). The 1-yr, 5-yr, and 10-yr overall survival rates of BPC were 96.9%, 80.0% and 73.6%, respectively. Univariate analysis showed age (P=0.000,1), smoking history (P=0.005), pathological subtype (P<0.000,1), T stage (P=0.000,2), TNM stage (P<0.000,1) were the prognostic factors. Multivariate analysis showed that age (P=0.005) and tumor stage (P=0.017) were independent prognostic factors.

CONCLUSIONS

BPC occurred more in middle-aged men. Surgery is the main treatment for lung cancer, and the overall prognosis is good. Age and TNM stage were independent risk factors for long-term survival after lung cancer surgery.

Treatment Patterns and Clinical Outcomes in Advanced Lung Neuroendocrine Tumors in Real-World Settings: A Multicenter Retrospective Chart Review Study

BACKGROUND

Using data from four tertiary referral centers in the U.S., we assessed real-world treatment patterns and clinical outcomes of patients with advanced lung neuroendocrine tumors (NETs).

SUBJECTS, MATERIALS, AND METHODS

We performed a retrospective chart review of adult patients with locally advanced/metastatic (typical/atypical) lung NETs treated between July 2011 and December 2014. Index date was histologically confirmed typical/atypical carcinoid tumor diagnosis date. Data included baseline characteristics, treatment patterns, progression, death, and lung NET-related health care resource use from index date through last contact/death. Time to treatment discontinuation and first progression, time from first to second progression, and overall survival (OS) were estimated using Kaplan-Meier analysis.

RESULTS

We identified 83 patients; 19 (23%) had functional NET. First-line treatments included somatostatin analogs (SSAs) alone (56%) or in combination with other therapies (6%), cytotoxic chemotherapy (20%), external beam radiation therapy (EBRT) (9%), liver-directed therapy (LDT) (4%), and everolimus/other (5%). Sixty patients had second-line therapy including SSA alone (18%) or in combination (40%), cytotoxic chemotherapy (17%), everolimus (12%), LDT (7%), EBRT (3%), and other treatments (3%). Median time (months) to first-line discontinuation were as follows: SSAs, 43.3; cytotoxic chemotherapy, 3.6. Overall median time (months) to investigator-assessed progression following treatment initiation was 12.4. Median OS (months) following treatment initiation was 66.4 for all patients and 81.5 for patients receiving SSAs.

CONCLUSION

SSAs, alone and in combination, are common treatments for advanced lung NETs. Patients have additional treatment options and relatively long survival compared with patients with other advanced cancers. Treatment pattern assessment following approval of newer treatments is needed.

IMPLICATIONS FOR PRACTICE

Somatostatin analogs (SSAs), cytotoxic chemotherapy, EBRT, liver-directed therapy, and targeted therapies are common treatments for locally advanced/metastatic (typical/atypical) lung neuroendocrine tumors (NETs). SSAs alone or in combination with other treatment modalities were the most common first- and second-line therapy, followed by cytotoxic chemotherapy. Patients continued treatment with SSAs long-term with median treatment duration of 43 months. Median overall survival was 66 months following initiation of first-line therapy for all patients. Treatment pattern assessment beyond the time period of this study is needed given recent U.S. Food and Drug Administration approvals for additional treatments for lung NETs that will likely be incorporated in the treatment landscape.

Primary neuroendocrine tumor in the presacral region: A case report

BACKGROUND

Primary neuroendocrine tumors (NETs) in the presacral region are extremely rare, some of which are caused by other primary tumors or metastatic rectal carcinoids. Nevertheless, cases of NETs have been increasing in recent years. This report describes the first primary neuroendocrine tumor in the presacral region that was found at our hospital within the last five years.

CASE SUMMARY

The patient was identified as a 36-year-old woman with a presacral mass and pelvic floor pain. A digital rectal examination revealed a presacral mass with unclear margins and obvious tenderness. Magnetic resonance imaging (MRI) demonstrated a 57 mm × 29 mm presacral lump. An ultrasound-guided needle biopsy confirmed a well-differentiated neuroendocrine tumor. No other primary or metastatic tumors were found.

CONCLUSION

Comprehensive consideration of our case report and literature reported by others suggests that a conclusive diagnosis of NETs should be based on computed tomography/MRI and pathological examinations. The treatment of primary NETs in the presacral region mainly relies on surgical procedures with follow-up.

Two types of ectopic Cushing syndrome or a continuum? Review

BACKGROUND

Two types of ectopic Cushing syndrome (ECS) are described: ECS associated with aggressive neoplasms, and ECS with indolent and occult tumors, however, there is a lack of studies that thoroughly review their characteristics.

METHODS

A systematic review was carried out on PUBMED of all the papers about the ECS, in order to better define the types of this subcategory of Cushing's syndrome, highlighting the differential aspects between these subgroups.

RESULTS

It was found that in 50% of cases the prototypic "aggressive" ECS is caused by small cell lung carcinomas (SCLC). In these cases, the clinical presentation may be atypical, predominating the signs and symptoms derived from the protein catabolism. Cortisol and ACTH levels are extremely high, the clinical presentation is abrupt (< 3-6 months) and the tumor is usually advanced, being impossible a curative treatment. On the other hand, "indolent" ECS is mainly represented by carcinoid tumors (CT). In these cases the clinical presentation overlaps enormously with that of Cushing's disease (CD). Cortisol and ACTH levels are slightly elevated, the clinical presentation is progressive (> 6 months) and the prognosis is usually good, and a curative treatment is possible in about 75% of the cases.

CONCLUSION

Although there is no absolute differentiation between the two extremes of ECS, a classification could be established in two groups, guided by its clinical and biochemical characteristics, and mainly by the type and stage of the ACTH-secreting tumor. However, a small percentage of tumors do not fit in this simple grouping, and may present both phenotypes or an intermediate one.

A single-institution retrospective analysis of metachronous and synchronous metastatic bronchial neuroendocrine tumors

Background

Broncho-pulmonary neuroendocrine tumors (bpNETs) are rare malignancies and there is no consensus on therapeutical management of metastatic disease and follow-up after radical resection.

Methods

Clinical records of patients with a cytological or histological diagnosis of bpNETs and distant metastases (metachronous or synchronous), evaluated at the European Institute of Oncology between 1997 and 2014, were retrospectively analyzed. Data on patient demographics, pathology, imaging exams, surgical and non-surgical treatments were collected. P value descriptive data, uni- and multi-variate survival analysis were generated for all variables.

Results

With a median follow-up of 53 [9-215] months, 61 patients with metachronous and 47 with synchronous metastases were analysed. The most common tool of first recurrence detection was computed tomography. Liver (67%), lymph node (25%), bone (22%) and lung (16%) were the most common sites of relapse. Median time to recurrence was 5 years. Median overall survival (OS) was 72 months for the whole population, with no significant difference between patients with synchronous and metachronous metastases. Age, bone metastases, liver metastases and Ki-67 as a continuous variable all significantly correlated with prognosis at the multivariate analysis.

Conclusions

This is one of the largest, single-centre, series of metastatic bpNETs. Among patients with metachronous metastases the pattern of recurrences was heterogeneous as were the follow-up exams used to detect them. The results of our analysis may represent solid bases for designing prospective clinical trials in homogeneous settings of bpNETs.

MGMT promoter methylation and 1p/19q co-deletion of surgically resected pulmonary carcinoid and large-cell neuroendocrine carcinoma

BACKGROUND

The response to temozolomide (TMZ) treatment in small-cell lung cancer (SCLC) correlated with O(6)-methylguanine -DNA methyltransferase (MGMT) promoter methylation. 1p/19q co-deletion within oligodendroglioma is a responsive predictor for TMZ. Currently, the status of MGMT promoter methylation and 1p/19q co-deletion in pulmonary carcinoid (PC) and large-cell neuroendocrine carcinoma (LCNEC) is not reported.

METHODS

Nine PC [two atypical carcinoids (AC), seven typical carcinoids (TC)] and six LCNEC patients were collected retrospectively. The pyrosequencing and fluorescence in situ hybridization were used to detect the MGMT promoter methylation and 1p/19q co-deletion in surgically resected specimens. Kaplan-Meier analysis was used to assess the rate of disease-free survival (DFS).

RESULTS

MGMT promoter methylation was found in two (2/6, 15.3%) LCNEC patients but not in any PC patients. Three (3/6, 50%) 1p and two (2/6, 33.3%) 19q single deletions were found in LCNEC patients. One 1p single deletion was found in AC patients. One (1/7, 14.3%) 1p and two (2/7, 28.6%) 19q single deletions were found in TC patients. After a median follow-up of 38 months, three LCNEC patients developed distant metastasis and one patient died of LCNEC disease. The DFS of PC patients was much longer than LCNEC patients (χ ²  = 7.565, P = 0.006).

CONCLUSIONS

MGMT promoter methylation and 1p/19q co-deletion might not be the ideal biomarkers for TMZ treatment in TC/AC patients. Thus, the detection of MGMT promoter methylation and whether it can be used as a medication for TMZ in LCNEC patients necessitates investigation. Furthermore, 1p deletion could be a negative prognostic factor for LCNEC patients.

Open issues on G3 neuroendocrine neoplasms: back to the future

The recent recognition that grade 3 (G3) neuroendocrine neoplasms (NENs) can be divided into two different categories according to the histopathological differentiation, that is G3 neuroendocrine tumors (NETs) and G3 neuroendocrine carcinomas (NECs) has generated a lot of interest concerning not only the diagnosis, but also the differential management of such new group of NENs. However, several issues need to be fully clarified in order to put G3 NETs and G3 NECs in the right place. The aim of this review is to focus on those issues that are still undetermined starting from the current knowledge, evaluating the available evidence and the possible clinical implications.

Entering the third decade of experience with octreotide LAR in neuroendocrine tumors: A review of current knowledge

Gastroenteropancreatic neuroendocrine tumors (NETs) are a relatively rare group of heterogeneous neoplasms. The most significant advance in therapy of NETs has been the advent of the somatostatin analog octreotide, which represents a cornerstone in their management and dramatically changed the therapeutic landscape. Octreotide long-acting release (LAR) was developed to overcome some of the limitations of octreotide. Several clinical studies, including PROMID and RADIANT-2, have validated the clinical benefits of octreotide LAR in NETs, with tumor shrinkage in about 10% of patients and tumor stabilization in roughly half of cases. While the use of octreotide LAR is well-consolidated in NETs, some open questions remain. These include the use of high-dose octreotide LAR, as there is evidence that higher dose may provide longer disease control, and nonstandard treatment schedules, with administration every 21 days instead of 28 days, as well as their use in combination with targeted agents or peptide receptor radiotherapy in clinical practice. After 3 decades of clinical experience with octreotide LAR, the drug has a well-established safety profile. It is well-tolerated and treatment discontinuations due to adverse events are uncommon. One exception is cholelithiasis, which may increase with longer duration of treatment. According to the literature data, octreotide LAR is currently recommended in both functioning and nonfunctioning advanced NETs. This review summarizes the available clinical data with octreotide LAR and also provides future perspectives on its possible uses in patients with NETs.

Telotristat ethyl: a novel agent for the therapy of carcinoid syndrome diarrhea

Carcinoid syndrome (CS), characterized by diarrhea and flushing, is present in 20% of patients with neuroendocrine tumors at diagnosis and becomes more frequent with progression. The diarrhea of CS is caused mainly by tumoral secretion of serotonin. It may not be fully controlled by somatostatin analogs, the currently indicated drugs for symptomatic relief. Telotristat ethyl is a novel inhibitor of tryptophan hydroxylase, the rate-limiting enzyme in serotonin biosynthesis. Administration of the drug decreases diarrhea in patients with CS. Telotristat ethyl was approved in February 2017 (USA) and September 2017 (European Commission) for the treatment of CS diarrhea in adults inadequately controlled by somatostatin analog alone. This drug is expected to greatly improve the health and quality of life of patients with CS diarrhea.

Do we really care about incidental lung nodules?-Review of atypical lung carcinoid and a proposal for systematic patient follow up

Atypical lung carcinoids are intermediate-grade neuroendocrine tumors (NETs) with malignant potential. They are often detected incidentally on imaging done for non-related causes, as the patients are frequently asymptomatic. Histopathology is required to confirm the diagnosis with immunohistochemistry (IHC). Due to their indolent nature, these are often diagnosed only in the advanced stages. Treatment options include chemoradiation for widespread disease versus surgery for local or minimally invasive disease. This article describes a nonsmoker female with enlarging solitary pulmonary nodule who was initially lost to follow up, subsequently operated and with final pathology revealing atypical lung carcinoid. This case stress on the schematic follow up of these incidentally detected pulmonary nodules. Inspired from the mandatory lay mammography report letters recommended by ACR, this article proposes sending lay letters to patients for pulmonary nodule follow up, directly from the Radiology Department to reinforce the importance of timely follow up, which will complement the information provided to the patient from their primary care physician or pulmonologist's office.