Early-Phase Thin-Slice CT in the Diagnosis of Small Insulinomas
Context Insulinomas, which are generally smaller than 2 cm, may be difficult to detect by routine imaging modalities including abdominal ultrasonography, computed tomography, and magnetic resonance imaging. Although preoperative detection of insulinomas is essential for operative planning, it is often challenging due to their small size. While arterial stimulation and venous sampling has been used in patients with insulinomas it has been largely supplanted by early-phase thin-slice computed tomography. Case report We report three patients with insulinomas, which were not detected by routine computed tomography scan, but were successfully imaged using early-phase thin-slice computed tomography. Enucleation was performed in all patients based on preoperative imaging. All three patients had an unremarkable postoperative course. Conclusion Early-phase thin-slice computed tomography is recommended for the preoperative identification of insulinomas. This non-invasive imaging technique should be considered before performing arterial stimulation and venous sampling.
Image. CT scan before and 35, 55, and 80 seconds after the administration of contrast agent.
Soga J, Yakuwa Y. Pancreatic endocrinomas: A statistical analysis of 1,857cases. J Hepatobilirary Pancreat Surg. 1994; 1: 522-9.
Boukhman MP, Karam JH, Shaver J, et al. Insulinoma - experience from 1950 to 1995. West J Med. 1998; 169: 98-104. [PMID: 9735690]
Mehrabi A, Fischer L, Hafezi M, et al. A systemic review of localization, surgical treatment options, and outcome of insulinoma. Pancreas. 2014; 43: 675-86. [PMID: 24921202]
Tsuzuki Y, Ishii H. Insulinoma - a statistical review of 358 cases of insulinoma reported from 1991 to 2000 in Japan (Article in Japanese). Nihon Rinsho. 2001; 59: 121-31. [PMID: 11808217]
Tucker ON, Crotty PL, Conlon KC. The management of insulinoma. Br J Surg. 2006; 93: 264-275. [PMID: 16498592]
Doppman JL, Miller DL, Chang R, et al. Insulinomas: localization with selective intraarterial injection of calcium. Radiology. 1991; 178: 237-41. [PMID: 1984311]
Ito K, Takada T, Amano H et al. Localization of islet-cell hyperplasia: value of pre- and intraoperative arterial stimulation and venous sampling. J Hepatobilirary Pancreat Surg. 2004; 11: 203-6. [PMID: 15235895]
Horino T, Takao T, Hashimoto K. A case with insulinoma diagnosed and localized preoperatively using contrast-enhanced ultrasonography (CEUS) and arterial stimulation and venous sampling (ASVS). Endocr J. 2006; 53: 141-6. [PMID: 16543684]
Tseng LM, Chen JY, Won JG, et al. The role of intra-arterial calcium stimulation test with hepatic venous sampling (IACS) in the management of occult insulinomas. Ann surg oncol. 2007; 14: 2121-7. [PMID: 17431724]
Morganstein DL, Lewis DH, Jackson J, et al. The role of arterial stimulation and simultaneous venous sampling in addition to cross-sectional imaging for localization of biochemically proven insulinoma. Eur Radiol. 2009; 19: 2467-73. [PMID: 19597822]
Guettier JM, Kam A, Chang R. Localization of insulinomas to regions of the pancreas by intraarterial calcium stimulation: the NIH experience. J Clin Endocrinol Metab. 2009; 94: 1074-80. [PMID: 19190102]
Kutsuna N, Yamazaki S, Itoh Y, et al. Arterial stimulation and venous sampling (ASVS) is useful for recurrent lesions of insulinoma: a case report. Surg Laparosc Endosc Percutan Tech. 2009; 19: 138-9. [PMID: 19692865]
Baba Y, Hayashi S, Senokuchi T, et al. Which indexes are appropriate among those derived from selective arterial calcium stimulation and venous sampling (ASVS) for diagnosing pancreatic insulinomas? Evaluation using receiver operating characteristics analysis. Pancreas. 2011; 40: 308-10. [PMID: 21311308]
Eguchi H, Tanemura M, Marubashi S, et al. Arterial stimulation and venous sampling for glucagonomas of the pancreas. Hepatogastroenterology. 2012; 59: 276-9. [PMID: 21940356]
Horton KM, Hruban RH, Yeo C, et al. Multi-detector row CT of pancreatic islet cell tumors. Radiographics. 2006; 26: 453-64. [PMID: 16549609]
Van Hoe L, Gryspeerdt S, Marchal G, et al. Helical CT for the preoperative localization of islet cell tumors of the pancreas: value of arterial and parenchymal phase images. Am J Roentgenol. 1995; 165: 1437-9. [PMID: 7484581]
Assalia A, Gagner M. Laparoscopic pancreatic surgery for islet cell tumors of the pancreas. World J Surg. 2004; 28: 1239-47. [PMID: 15517485]
Grover AC, Skarulis M, Alexander HR, et al. A prospective evaluation of laparoscopic exploration with intraoperative ultrasound as a technique for localizing sporadic insulinomas. Surgery. 2005; 138: 1003-8. [PMID: 16360384]
Wong M, Isa SH, Zahiah M, et al. Intraoperative ultrasound with palpation is still superior to intra-arterial calcium stimulation test in localizing insulinoma. World J Surg. 2007; 31: 586-92. [PMID: 17322973]
Ambrose J. Computerized x-ray scanning of the brain. J Neurosurg. 1974; 40(6): 679-95. [PMID: 4596994]
King AD, Ko GT, Yeung VT, Chow CC, Griffith J, Cockram CS. Dual phase spiral CT in the detection of small insulinomas of the pancreas. Br J Radio 1998. 71:20-3. [PMID: 9534694]
Liu Y, Song Q, Jin HT, Lin XZ and Chen KM. The value of multidetector row CT in the preoperative detection of pancreatic insulimomas. Radiol Med 2009. 114:1232-8. [PMID: 19789954]
Zamboni GA, Bernardin L, Mucelli P. Dynamic MDCT of the pancreas: is time-density curve morphology useful for the differential diagnosis of solid lesions? A preliminary report. Eur J Radiol. 2012; 81: 381-5. [PMID: 22197731]
Hirshberg B, Libutti SK, Alexander HR, et al. Blind distal pancreatectomy for occult insulinoma, an inadvisable procedure. J Am Coll Surg. 2002; 194: 761-4. [PMID: 12081066]
Copyright (c) 2015 Hideki Ishioka, Naohiro Sata, Yasunao Ishiguro, Alan Lefor, Yoshikazu Yasuda
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