Kakizawa Keisuke, Yamashita Miho, Nakashima Mitsuko, Kawauchi Yuto, Ikeya Akira, Matsushita Akio, Sasaki Shigekazu, Oki Yutaka
Second Department of Internal Medicine, Hamamatsu University School of Medicine, Hamamatsu, Shizuoka, 431-3192, Japan.
Department of Internationalization Center, Hamamatsu University School of Medicine, Hamamatsu, Shizuoka, 431-3192, Japan.
J Endocr Soc. 2021 Nov 14;5(12):bvab171. doi: 10.1210/jendso/bvab171. eCollection 2021 Dec 1.
Paraganglioma (PGL) is a rare tumor originating from extra-adrenal paraganglionic chromaffin tissues, and most sympathetic PGLs have excessive catecholamine secretion. However, nonfunctional PGLs are sometimes found. Although malignant PGL is defined by metastasis to nonchromaffin tissues, it is difficult to predict malignancies due to the lack of reliable markers of potential malignancies. We report the case of a 69-year-old Japanese woman with an incidental retroperitoneal tumor and multiple enlarged mesenteric lymph nodes simultaneously. The patient had no subjective symptoms and there were no laboratory findings suggesting catecholamine hypersecretion. Both the retroperitoneal tumor and the enlarged mesenteric lymph nodes showed high accumulation of fluorodeoxyglucose (FDG), whereas metaiodobenzylguanidine (MIBG) was accumulated only at the retroperitoneal tumor. Although a retroperitoneal tumor was diagnosed as nonfunctional PGL by examination including MIBG scintigraphy, the cause of enlarged mesenteric lymph nodes could not be diagnosed by imaging and biochemical tests. As a result of retroperitoneal tumor resection and mesenteric lymph nodes sampling, histopathological examination revealed that a retroperitoneal tumor was PGL and enlarged mesenteric lymph nodes were follicular lymphoma. To reveal an underlying genetic factor, we performed whole exome sequencing of genomic DNA, and we identified 2 possible candidate variants in and but the pathogenicity of these variants remains uncertain in the present case. This rare case reinforces the importance of histopathological diagnosis of nonchromaffin tissue lesions in patients with PGL for the appropriate treatment strategy.
副神经节瘤（PGL）是一种起源于肾上腺外副神经节嗜铬组织的罕见肿瘤，大多数交感神经PGL有过量儿茶酚胺分泌。然而，有时会发现无功能的PGL。尽管恶性PGL通过转移至非嗜铬组织来定义，但由于缺乏潜在恶性肿瘤的可靠标志物，很难预测恶性情况。我们报告一例69岁日本女性病例，其同时偶然发现腹膜后肿瘤和多个肠系膜淋巴结肿大。患者无主观症状，也没有实验室检查结果提示儿茶酚胺分泌过多。腹膜后肿瘤和肿大的肠系膜淋巴结均显示氟脱氧葡萄糖（FDG）高摄取，而间碘苄胍（MIBG）仅在腹膜后肿瘤处摄取。尽管通过包括MIBG闪烁显像在内的检查，腹膜后肿瘤被诊断为无功能PGL，但通过影像学和生化检查无法诊断肠系膜淋巴结肿大的原因。经腹膜后肿瘤切除和肠系膜淋巴结取样，组织病理学检查显示腹膜后肿瘤为PGL，肿大的肠系膜淋巴结为滤泡性淋巴瘤。为揭示潜在的遗传因素，我们对基因组DNA进行了全外显子测序，在[具体基因]中鉴定出2个可能的候选变异，但在本病例中这些变异的致病性仍不确定。这个罕见病例强化了对PGL患者非嗜铬组织病变进行组织病理学诊断以制定合适治疗策略的重要性。
