Hospital Padre Américo, Unidade Local de Saúde do Tâmega e Sousa, Penafiel, Portugal.
Department of Endocrinology, Portuguese Oncology Institute of Porto (IPO Porto), Porto, Portugal.
Front Endocrinol (Lausanne). 2024 Sep 6;15:1405835. doi: 10.3389/fendo.2024.1405835. eCollection 2024.
Alpha-cell hyperplasia (ACH) is a rare pancreatic endocrine condition. Three types of ACH have been described: functional or nonglucagonoma hyperglucagonemic glucagonoma syndrome, reactive or secondary to defective glucagon signaling, and non-functional. Few cases of ACH with concomitant pancreatic neuroendocrine tumors (pNETs) have been reported and its etiology remains poorly understood. A case report of non-functional ACH with glucagon-producing NET is herein presented.
A 72-year-old male was referred to our institution for a 2 cm single pNET incidentally found during imaging for acute cholecystitis. The patient's past medical history included type 2 diabetes (T2D) diagnosed 12 years earlier, for which he was prescribed metformin, dapagliflozin, and semaglutide. The pNET was clinically and biochemically non-functioning, apart from mildly elevated glucagon 217 pg/ml (<209), and Ga-SSTR PET/CT positive uptake was only found at the pancreatic tail (SUVmax 11.45). The patient underwent a caudal pancreatectomy and the post-operative Ga-SSTR PET/CT was negative. A multifocal well-differentiated NET G1, pT1N0M0R0 (mf) strongly staining for glucagon on a background neuroendocrine alpha-cell hyperplasia with some degree of acinar fibrosis was identified on pathology analysis.
This case reports the incidental finding of a clinically non-functioning pNET in a patient with T2D and elevated glucagon levels, unexpectedly diagnosed as glucagon-producing NET and ACH. A high level of suspicion was required to conduct the glucagon immunostaining, which is not part of the pathology routine for a clinically non-functioning pNET, and was key for the diagnosis that otherwise would have been missed. This case highlights the need to consider the diagnosis of glucagon-producing pNET on an ACH background even in the absence of glucagonoma syndrome.
α 细胞增生症（ACH）是一种罕见的胰腺内分泌疾病。已描述了三种类型的 ACH：功能性或非胰高血糖素瘤性高胰高血糖素血症、胰高血糖素综合征、反应性或继发于胰高血糖素信号缺陷、非功能性。已报道了少数伴有胰腺神经内分泌肿瘤（pNET）的 ACH 病例，其病因仍知之甚少。本文报告了一例伴有胰高血糖素分泌 NET 的非功能性 ACH 病例。
一名 72 岁男性因急性胆囊炎影像学检查时偶然发现 2 cm 单发 pNET 而被转至我院。患者的既往病史包括 12 年前诊断的 2 型糖尿病（T2D），为此他服用二甲双胍、达格列净和司美格鲁肽。pNET 临床上和生化上均无功能，除了胰高血糖素轻度升高（217 pg/ml [<209]）外，Ga-SSTR PET/CT 仅在胰腺尾部发现阳性摄取（SUVmax 11.45）。患者接受了尾部胰腺切除术，术后 Ga-SSTR PET/CT 为阴性。病理分析显示，存在多发、分化良好的 NET G1、pT1N0M0R0（mf），在背景神经内分泌α细胞增生的基础上强烈表达胰高血糖素，伴有一定程度的腺泡纤维化。
本病例报告了 T2D 患者和胰高血糖素水平升高时意外发现的临床无功能 pNET，意外诊断为胰高血糖素分泌 NET 和 ACH。需要高度怀疑进行胰高血糖素免疫染色，这不是临床无功能 pNET 病理常规的一部分，是诊断的关键，否则会被遗漏。本病例强调了即使没有胰高血糖素瘤综合征，也需要考虑在 ACH 背景下诊断胰高血糖素分泌 pNET。
