N-staging in large cell neuroendocrine carcinoma of the lung: diagnostic value of [18F]FDG PET/CT compared to the histopathology reference standard

Pulmonary neuroendocrine cells: Spectrum of diseases and their radiological-pathological correlations

Pulmonary neuroendocrine cells, which constitute a small percentage (0.4%) of airway epithelial cells, play a key role in hypoxia detection, epithelial growth and regeneration, and in lung organogenesis through the synthesis and secretion of amines and peptides. Lesions resulting from pulmonary neuroendocrine cell proliferation range from benign and indolent to malignant and highly aggressive. The recently updated WHO classification of pulmonary neuroendocrine neoplasms includes typical and atypical carcinoid tumours as well as high-grade neuroendocrine carcinomas: large cell neuroendocrine carcinomas and small cell carcinomas. This classification also recognises a condition known as diffuse idiopathic pulmonary neuroendocrine cell hyperplasia (DIPNECH) as a distinct entity. Radiologists need to become familiar with these pathologies as the symptoms often lack specificity, and thus imaging plays a crucial role in diagnosis. An understanding of the correlation between the radiological and pathological examinations of these pathologies can enhance our awareness of the wide spectrum of imaging manifestations.

Pulmonary Large-Cell Neuroendocrine Carcinoma, a Multifaceted Disease-Case Report and Literature Review

Background and Clinical Significance: This article explores the complexity of large-cell neuroendocrine carcinoma (LCNEC) by presenting a clinical case involving a 17-year-old admitted for persistent wheezing, with no history of respiratory toxin exposure, a background of atopy, and a suspected diagnosis of bronchial asthma. Given the patient's age and the nature of the symptoms, the condition was initially diagnosed as asthma, leading to the initiation of maximum inhalation therapy. Case Presentation: Despite proper adherence and correct administration, symptoms persisted, necessitating the use of oral corticosteroids. Imaging revealed an extensive inhomogeneous mass in the cervical esophagus and trachea, along with a similar tumor in the right hilum, prompting bronchoscopy. The diagnosis of LCNEC was confirmed through imaging, histopathological findings, and a detailed immunohistochemical profile. Initially misdiagnosed as adenoid cystic carcinoma, this case highlights the diagnostic challenges and the importance of rigorous evaluation. Conclusions: It emphasizes that recurrent wheezing in adolescents is not always indicative of asthma and requires careful differential diagnosis to uncover less common causes.

Neoadjuvant nivolumab with or without relatlimab in resectable non-small-cell lung cancer: a randomized phase 2 trial

Antibodies targeting the immune checkpoint molecules PD-1, PD-L1 and CTLA-4, administered alone or in combination with chemotherapy, are the standard of care in most patients with metastatic non-small-cell lung cancers. When given before curative surgery, tumor responses and improved event-free survival are achieved. New antibody combinations may be more efficacious and tolerable. In an ongoing, open-label phase 2 study, 60 biomarker-unselected, treatment-naive patients with resectable non-small-cell lung cancer were randomized to receive two preoperative doses of nivolumab (anti-PD-1) with or without relatlimab (anti-LAG-3) antibody therapy. The primary study endpoint was the feasibility of surgery within 43 days, which was met by all patients. Curative resection was achieved in 95% of patients. Secondary endpoints included pathological and radiographic response rates, pathologically complete resection rates, disease-free and overall survival rates, and safety. Major pathological (≤10% viable tumor cells) and objective radiographic responses were achieved in 27% and 10% (nivolumab) and in 30% and 27% (nivolumab and relatlimab) of patients, respectively. In 100% (nivolumab) and 90% (nivolumab and relatlimab) of patients, tumors and lymph nodes were pathologically completely resected. With 12 months median duration of follow-up, disease-free survival and overall survival rates at 12 months were 89% and 93% (nivolumab), and 93% and 100% (nivolumab and relatlimab). Both treatments were safe with grade ≥3 treatment-emergent adverse events reported in 10% and 13% of patients per study arm. Exploratory analyses provided insights into biological processes triggered by preoperative immunotherapy. This study establishes the feasibility and safety of dual targeting of PD-1 and LAG-3 before lung cancer surgery.ClinicalTrials.gov Indentifier: NCT04205552 .

Prognostic Factors across Poorly Differentiated Neuroendocrine Neoplasms: A Pooled Analysis

INTRODUCTION

Poorly differentiated neuroendocrine carcinomas (NECs) are characterized by aggressive clinical course and poor prognosis. No reliable prognostic markers have been validated to date; thus, the definition of a specific NEC prognostic algorithm represents a clinical need. This study aimed to analyze a large NEC case series to validate the specific prognostic factors identified in previous studies on gastro-entero-pancreatic and lung NECs and to assess if further prognostic parameters can be isolated.

METHODS

A pooled analysis of four NEC retrospective studies was performed to evaluate the prognostic role of Ki-67 cut-off, the overall survival (OS) according to primary cancer site, and further prognostic parameters using multivariable Cox proportional hazards model and machine learning random survival forest (RSF).

RESULTS

422 NECs were analyzed. The most represented tumor site was the colorectum (n = 156, 37%), followed by the lungs (n = 111, 26%), gastroesophageal site (n = 83, 20%; 66 gastric, 79%) and pancreas (n = 42, 10%). The Ki-67 index was the most relevant predictor, followed by morphology (pure or mixed/combined NECs), stage, and site. The predicted RSF response for survival at 1, 2, or 3 years showed decreasing survival with increasing Ki-67, pure NEC morphology, stage III-IV, and colorectal NEC disease. Patients with Ki-67 <55% and mixed/combined morphology had better survival than those with pure morphology. Morphology pure or mixed/combined became irrelevant in NEC survival when Ki-67 was ≥55%. The prognosis of metastatic patients who did not receive any treatment tended to be worse compared to that of the treated group. The prognostic impact of Rb1 immunolabeling appears to be limited when multiple risk factors are simultaneously assessed.

CONCLUSION

The most effective parameters to predict OS for NEC patients could be Ki-67, pure or mixed/combined morphology, stage, and site.

Large Cell Neuroendocrine Carcinoma of the Lung: Current Understanding and Challenges

Large cell neuroendocrine carcinoma of the lung (LCNEC) is a rare and highly aggressive type of lung cancer, with a complex biology that shares similarities with both small-cell lung cancer (SCLC) and non-small-cell lung cancer (NSCLC). The prognosis of LCNEC is poor, with a median overall survival of 8-12 months. The diagnosis of LCNEC requires the identification of neuroendocrine morphology and the expression of at least one of the neuroendocrine markers (chromogranin A, synaptophysin or CD56). In the last few years, the introduction of next-generation sequencing allowed the identification of molecular subtypes of LCNEC, with prognostic and potential therapeutic implications: one subtype is similar to SCLC (SCLC-like), while the other is similar to NSCLC (NSCLC-like). Because of LCNEC rarity, most evidence comes from small retrospective studies and treatment strategies that are extrapolated from those adopted in patients with SCLC and NSCLC. Nevertheless, limited but promising data about targeted therapies and immune checkpoint inhibitors in patients with LCNEC are emerging. LCNEC clinical management is still controversial and standardized treatment strategies are currently lacking. The aim of this manuscript is to review clinical and molecular data about LCNEC to better understand the optimal management and the potential prognostic and therapeutic implications of molecular subtypes.