Case report: CT of a duodenal paraganglioma

Paraganglioma is a neoplasm of neuroectodermal origin that occurs rarely in the bowel. This case report illustrates the previously undescribed CT appearance of a duodenal paraganglioma. An intensely enhancing mass in the region of the pancreatic head was found. The intense enhancement ruled out adenocarcinoma and focal pancreatitis. An islet cell tumor of the pancreas was the major differential diagnostic consideration.     

副神经节细胞瘤的影像诊断

目的探讨副神经节细胞瘤的影像特点，提高其诊断正准率。方法对25例副神经节细胞瘤的影像资料进行分析，探讨不同影像检查方法诊断副神经节细胞瘤的价值。结果16例位于腹膜后、4例位于心脏、2例位于膀胱、2例位于胸腔近膈顶处、1例位于肝门区。以囊实性为主，与周围组织分界不清，MR及CT平扫肿瘤信号及密度不均匀，增强扫描实性部分可明显强化。17例肾上腺髓质^131I-间碘苄胍（^131I-MIBG）显像阳性率为88．2％（15例）；7例行生长抑素受体^99Tc^m-奥曲肽（^99Tc^m-octreotide）显像者，6例阳性。结论CT、MRI可显示肿瘤内部结构特征及与周围组织的关系，^131I-MIBG显像有定性价值，^99Tc-octreotide显像可提供补充信息。     

Melanotic paraganglioma of the posterior mediastinum

A melanotic paraganglioma occurred in a 57-year-old woman, located in the left paravertebral space of the upper mediastinum. It was totally resected. During a 5 year follow up period neither tumour reccurrence nor metastasis were observed. Histological examination of the tumour revealed a paraganglioma with monomorphous chief cell like elements which were arranged in a zellballen pattern. Immunohistochemical results also were in accordance with the diagnosis since neuron-specific enolase, chromogranin and synaptophysin were found in tumour cells whereas keratin was not. Additionally, neurosecretory granules were found in tumour cells during electron microscopy. A peculiar feature of the tumour was its strong pigmentation due to melanin located within the tumour cells and tumour associated melanophages. The simultaneous expression of functional properties of two different neural crest derived cells in one tumour stresses the close relationship between all neural crest elements and is in accordance with the observation of other melanotic, non-melanomatous tumours.Dedicated to Prof. Dr. Dr. mult. h.c. W. Doerr on the occasion of his 80th birthday     

Neurogenic polyps

A neoplastic proliferation of peripheral nerve sheath cells (Schwann cells, fibroblasts and perineurial cells) and ganglion cells in the colorectum may give rise to the mucosal or submucosal polyps. Depending upon the predominant cell types, these neurogenic polyps can be classified as schwannomas, granular cell tumours, neurofibromas, perineuriomas, mixed nerve sheath tumours, ganglioneuromas or paragangliomas. Morphologically, the neoplastic cells repeat or mimic the corresponding nerve sheath cells or neurons in terms of growth pattern, histology and immunoreactivity. They are uncommon, but the polyps can occur in any age group, although the vast majority of patients are adults. The polyps can be either solitary (most peripheral nerve sheath tumours) or multiple, especially if associated with systemic diseases (i.e. syndromes involving the peripheral nerve tissue). They are usually incidental findings or may be accompanied by gastrointestinal symptoms. Almost all colorectal neurogenic polyps are benign, and they rarely undergo malignant transformation unless they are part of a syndromatic manifestation. However, these polyps may cause a diagnostic problem during screening for colorectal cancer. An accurate diagnosis of these entities will help clinicians to make appropriate management decisions.     

Functional paraganglioma with tumor thrombus in the inferior vena cava,first case report

Pheochromocytoma (PHEO) is a rare neuroendocrine that tumor originated from the adrenal medulla that secrets catecholamines. Tumors from extra-adrenal chromaffin tissues are called extra-adrenal PHEO or paraganglioma (PGL). To our knowledge, adrenal PHEO and subclinical PGL with inferior vena cava (IVC) invasion had been sporadically reported, while functional PGL with IVC tumor thrombus has not been publicly reported yet. Perioperative management of those diseases is less well established because of their multidisciplinary nature and rarity. We herein present a case of primary malignant PGL with IVC invasion. A 16-year-old female patient with a history of severe paroxysmal hypertension was admitted to Peking Union Medical College Hospital on suspicion of retroperitoneal mass. In-house diagnostic work-up revealed a malignant PGL with IVC invasion, inferior mesenteric artery encasement and, aorta engagement. Multi-disciplinary discussions were held and careful preoperative preparation plans were made. After everything was ready, the functional PGL and tumor thrombus were completely resected, then a reconstruction of IVC was performed. The patient was discharged on postoperative day 14 and all her clinical symptoms disappeared afterward. No evidence of tumor residual or metastasis was found in the subsequent six months of follow-up. Gene tests were made for her and her family. Albeit its rarity, functional PGL with IVC invasion is not unresectable, a multi-disciplinary task force should be established to settle down every detail. We recommended 3-dimensional imaging reconstruction for gaining a better anatomic understanding. Literature reviews showed that complete resection is the premise of a good prognosis. In particular cases, complementary or alternative therapy like chemotherapy and ¹³¹I-metaiodobenzylguanidine might help, family hereditary genetic tests are advised as well.     

Molecular basis of carotid body tumor and associated clinical features in Japan identified by genomic,immunohistochemical, and clinical analyses

Carotid body tumor (CBT) is classified as a paraganglioma (PGL). Here, we report the genetic background, protein expression pattern, and clinical findings of 30 Japanese CBT cases. Germline pathogenic or likely pathogenic (P/LP) variants of genes encoding succinate dehydrogenase subunits (SDHs) were detected in 15 of 30 cases (50%). The SDHB variants were the most frequently detected, followed by SDHA and SDHD variants. One case with SDHAF2 variant was bilateral CBT, and other two multiple PGL cases were not detected P/LP variants. The three cases with germline variants that could be tested did not have somatic P/LP variants of the same genes. Immunohistochemical analysis showed negative SDHB signals in CBT tissues in five cases with germline P/LP variants of SDHB, SDHD, or SDHA. In addition, SDHB signals in CBT tissues were negative in four of nine cases without germline P/LP variants of SDHs. These findings suggest the involvement of unidentified molecular mechanisms affecting SDHs.     

原发性支气管副神经节瘤一例的探讨

目的提高对支气管副神经节瘤的临床病理特征、诊断及治疗的认识。方法回顾性分析我科收治的1例原发性支气管副节瘤患者的临床资料,结合文献复习讨论支气管副节瘤的诊断和治疗特点。结果原发性支气管副神经节瘤罕见,常表现为咯血及阻塞性肺炎表现,CT及气管镜下病理可明确诊断。免疫组化示CgA、和S-100蛋白阳性,CK阴性NSE。经内镜下肿瘤切除及支气管袖状切除是治疗首选。结论原发性副神经节瘤诊断需结合临床表现、病理及免疫组化结果。因其为潜在恶性肿瘤,术后应长期随访。