Adjuvant therapy for lung neuroendocrine neoplasms

A Rare Case of Diffuse Idiopathic Pulmonary Neuroendocrine Cell Hyperplasia: A Case Report

Diffuse idiopathic pulmonary neuroendocrine cell hyperplasia (DIPNECH) is a rare pulmonary disease characterized by the diffuse proliferation of neuroendocrine cells in the bronchial epithelium. It is considered a preinvasive precursor to carcinoid tumors and usually presents with obstructive symptoms. We present the case of a 71-year-old female, non-smoker, with a past medical history of asthma, osteoarthritis, allergic rhinitis, and hyperlipidemia who was referred to the pulmonology clinic in view of incidental chest CT findings of multiple pulmonary nodules. Physical examination and labs were unremarkable. CT of the chest showed scattered multiple noncalcified pulmonary nodules with a 10 mm dominant nodule in the inferior right middle lobe and several subcentimeter hypodensities in the left and right lobes of the lung. A PET scan confirmed the CT findings along with no abnormal hypermetabolic activity to suggest malignancy. The patient was followed up in the pulmonology clinic at six months, 12 months, and then 18 months. At 18 months owing to a slight increase in the size of the largest lung nodule, a CT-guided biopsy done was conclusive of a carcinoid. The tumor cells were positive for synaptophysin, chromogranin, insulinoma-associated protein 1 (INSM-1), and thyroid transcription factor 1 (TTF-1). The Ki-67 (Keil) index was <1%. A video-assisted thoracic surgery with right middle lobectomy along with mediastinal lymph node dissection was then done, and the patient was found to have stage pT1aN0 typical carcinoid tumor (1.0 cm), with multiple carcinoid tumors and neuroendocrine hyperplasia, consistent with DIPNECH. She has been under clinical follow-up for over three years at present and continues to be asymptomatic with complete remission following surgery. DIPNECH primarily affects middle-aged, non-smoking females who present with cough and dyspnea, and diagnosis is often delayed due to clinical features overlapping with those of obstructive lung disease. Imaging shows lung nodules, ground-glass opacities, and/or mosaic attenuation. Due to the rarity of the conditions, there are no established clinical trials, and therefore, there is a need to establish guidelines.

Diagnosis and Treatment of Lung Neuroendocrine Neoplasms: Somatostatin Receptor PET Imaging and Peptide Receptor Radionuclide Therapy

Recently, advancement of somatostatin receptor (SSTR) imaging and theragnostic approach using peptide receptor radionuclide therapy (PRRT) have changed the paradigm of diagnosis and management of neuroendocrine tumor. 68Ga-DOTATATE PET/CT can diagnose the lung carcinoids with high SSTR expression. With combination of 68Ga-DOTATATE PET/CT and 18F-FDG PET/CT, tumor heterogeneity of lung carcinoid can be identified, which may guide optimal patient selection for PRRT. PRRT may be an effective and safe treatment of advanced lung carcinoids during progression with first-line somatostatin analog therapy. This review provides updates on the diagnosis and management of lung carcinoids, focusing on SSTR imaging and PRRT.

Current Management of Carcinoid Tumor

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

Hierarchical identification of a transcriptional panel for the histological diagnosis of lung neuroendocrine tumors

Background: Lung cancer is a complex disease composed of neuroendocrine (NE) and non-NE tumors. Accurate diagnosis of lung cancer is essential in guiding therapeutic management. Several transcriptional signatures have been reported to distinguish between adenocarcinoma (ADC) and squamous cell carcinoma (SCC) belonging to non-NE tumors. This study aims to identify a transcriptional panel that could distinguish the histological subtypes of NE tumors to complement the morphology-based classification of an individual.

Methods: A public dataset with NE subtypes, including 21 small-cell lung cancer (SCLC), 56 large-cell NE carcinomas (LCNECs), and 24 carcinoids (CARCIs), and non-NE subtypes, including 85 ADC and 61 SCC, was used as a training set. In the training set, consensus clustering was first used to filter out the samples whose expression patterns disagreed with their histological subtypes. Then, a rank-based method was proposed to develop a panel of transcriptional signatures for determining the NE subtype for an individual, based on the within-sample relative gene expression orderings of gene pairs. Twenty-three public datasets with a total of 3,454 samples, which were derived from fresh-frozen, formalin-fixed paraffin-embedded, biopsies, and single cells, were used for validation. Clinical feasibility was tested in 10 SCLC biopsy specimens collected from cancer hospitals via bronchoscopy.

Results: The NEsubtype-panel was composed of three signatures that could distinguish NE from non-NE, CARCI from non-CARCI, and SCLC from LCNEC step by step and ultimately determine the histological subtype for each NE sample. The three signatures achieved high average concordance rates with 97.31%, 98.11%, and 90.63%, respectively, in the 23 public validation datasets. It is worth noting that the 10 clinic-derived SCLC samples diagnosed via immunohistochemical staining were also accurately predicted by the NEsubtype-panel. Furthermore, the subtype-specific gene expression patterns and survival analyses provided evidence for the rationality of the reclassification by the NEsubtype-panel.

Conclusion: The rank-based NEsubtype-panel could accurately distinguish lung NE from non-NE tumors and determine NE subtypes even in clinically challenging samples (such as biopsy). The panel together with our previously reported signature (KRT5-AGR2) for SCC and ADC would be an auxiliary test for the histological diagnosis of lung cancer.

Ectopic ACTH syndrome complicated by hypercortisolism-associated urolithiasis. A case report

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Nephrolithiasis is a frequent and underestimated complication of Cushing’s syndrome (CS), prevalence soars up to 50 % in adult patients with active CS, and 25% in cured patients in whom certain abnormalities contribute to stone recurrence

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Ectopic ACTH secretion (EAS) is a less common cause of Cushing syndrome and is seen in 5 to 10% of cases with endogenous hypercortisolemia. Sudden and dramatic onset of CS often suggests an ectopic ACTH-secreting tumor.

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There is no information in any urological clinical practice guideline in relation to management of nephrolithiasis in Cushing’s syndrome, follow-up in glucocorticoid-induced nephrolithiasis should be tailored to each patient.

Bronchial Carcinoids: From Molecular Background to Treatment Approach

Simple Summary

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

Abstract

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