Lee Yelim, Rodrigs Ryan, Wallace William Dean, Wightman Sean C
Keck School of Medicine, The University of Southern California, Los Angeles, CA, USA.
Department of Pathology, Keck School of Medicine, The University of Southern California, Los Angeles, CA, USA.
Case Rep Oncol. 2024 Sep 18;17(1):1042-1049. doi: 10.1159/000540889. eCollection 2024 Jan-Dec.
Large cell neuroendocrine carcinoma (LCNEC) and atypical carcinoid (AC) tumor are two distinct types of pulmonary neuroendocrine tumors (NETs) that are considered genetically unrelated. AC is categorized as a well-differentiated NET, while LCNEC is considered a poorly differentiated NET with a significantly poorer prognosis.
In this case report, we present an 83-year-old male who presented with 2-day history of hemoptysis and subsequently diagnosed with a right upper lobe carcinoid tumor on pre-excision biopsy. After evaluation of the entire excised specimen, the tumor was subsequently reclassified as LCNEC. This case is rare as the tumor displayed pathologic features of AC (areas with low mitotic activity and punctate necrosis) alternating with areas of LCNEC (high mitotic activity with sheets of necrosis). Subsequent molecular studies were more characteristic of AC, with no mutations detected in Rb1 or p53. The patient underwent surgical resection (right upper lobectomy with bronchoplasty and mediastinal lymph node dissection) to remove the tumor.
This report outlines the clinical presentation and the underlying pathology of this rare case, which underscores the complex molecular landscape of neuroendocrine neoplasms and the need for nuanced molecular analyses in refining diagnostic approaches.
大细胞神经内分泌癌（LCNEC）和非典型类癌（AC）肿瘤是两种不同类型的肺神经内分泌肿瘤（NETs），被认为在基因上无关联。AC被归类为高分化NET，而LCNEC被认为是低分化NET，预后明显较差。
在本病例报告中，我们介绍了一名83岁男性，他有2天咯血病史，术前活检后被诊断为右上叶类癌肿瘤。对整个切除标本进行评估后，该肿瘤随后被重新分类为LCNEC。该病例罕见，因为肿瘤表现出AC的病理特征（有低有丝分裂活性和点状坏死区域）与LCNEC区域（高有丝分裂活性伴大片坏死）交替出现。随后的分子研究更具AC特征，未在Rb1或p53中检测到突变。患者接受了手术切除（右上叶切除加支气管成形术和纵隔淋巴结清扫）以切除肿瘤。
本报告概述了这一罕见病例的临床表现和潜在病理，强调了神经内分泌肿瘤复杂的分子格局以及在完善诊断方法中进行细致分子分析的必要性。
