Paraganglioma of the pancreas: case report and literature review

LETTERS TO THE EDITOR

Paraganglioma of the pancreas: case report and literature review

Antônio Nocchi Kalil^I,II; Gustavo Andreazza Laporte^I,II; Marinez Bizarro Barra^III; Tiago Auatt Paes Remonti^II; Felipe Rodrigues Cunha^II; Rafael Seitenfus^II

^IUniversidade Federal de Ciências da Saúde de Porto Alegre

^IIServiço de Cancerologia Cirúrgica do Hospital Santa Rita da Santa Casa de Misericórdia de Porto Alegre

^IIIServiço de Patologia Santa Casa de Misericórdia de Porto Alegre, Porto Alegre, RS, Brasil

^{Correspondence}

INTRODUCTION

Paraganglioma is a rare neuroendocrine tumor affecting about 1 out of 2.000.000 of the population. It arises from neural crest, including tissues such as the adrenal medulla, carotid and aortic bodies, organs of Zuckerkandl, and other unnamed paragangliomas^6,8.

Only 15 cases, including the present one, have been reported worldwide. The preoperative diagnosis is difficult to obtain, because it is sometimes confounded with other types of tumor. In general, it affects 65-year-old patients. In the contrast-enhanced CT scans, the tumors appear as soft-tissue masses with either homogeneous enhancement or central areas of low attenuation. The presentation is a solid in small tumor or cystic in larger tumors (>6 cm). Most paragangliomas follow a benign clinical course. The treatment of the choice is surgical resection and this case is the first described in Brasil.

CASE REPORT

A 73-year-old woman was admitted to our hospital complaining about right upper abdominal pains, 15 kg weight loss in one year and periodical post-prandial vomiting. She presented an abdominal ultrasonography showing a 2,5 cm mass at the head of the pancreas. The lesion was identified as a 2,5 x 1,7 cm low-intensity mass in T1 and T2 weighted magnetic resonance images. Magnetic resonance imaging with enhanced contrast revealed a homogeneous enhanced image in the arterial phase and venous phase. A contrast-enhanced computed tomography (CT) showed an enhanced lesion of 2,3 x 1,8cm in the head of the pancreas, with well defined limits (Figure 1). Laboratory studies gave normal results except for CA19-9 level, which was in superior limits of normality 35 U/mL (normal range 0-35 U/mL).

The patient was submitted to a pancreatoduodenectomy with complete excision of the lesion, (Figure 2) with an uneventful postoperative course, and, in March 2010 one year after her operation, she was feeling well. The histological findings identified the "Zellballen" pattern and the immunohistochemistry revealed positive staining of synaptophysin, chromogranin A and S-100 protein (Figure 3).

DISCUSSION

Although paraganglioma can occur anywhere in the para-aortic region, the tumours are frequently found in the infrarenal area near the origin of the inferior mesenteric artery, where the organs of Zuckerkandl are located^6,7,8. Other less common locations for abdominal paragangliomas include gallblader, urinary bladder, prostate, spermatic cord, uterus, and duodenum. Paraganglioma of the pancreas is extremely rare, and only 14 cases, including the present one, have been reported worldwide^2,3,4,56,7,8. When the diagnosis of paraganglioma is made, it's necessary screening other tumours, because until now this type of neoplasm has been considered part of multiple endocrine neoplasia syndrome, secundary of genetic alteration predisposing presence of multiple tumors¹.

The mean age of the 15 patients was 63 years, ranging from 41 to 85 years. Five patients were men, and 10, women. In 10 out of the 14 cases, the tumor was located in the head of the pancreas, and 5 were located in the body or tail.

Because paraganglioma of the pancreas is sometimes confounded with pseudocyst or endocrine tumor, it is difficult to obtain a preoperative diagnosis, especially in nonfunctional cases^2,8.

The diagnosis was established by imaging exams revealing a well-defined mass with frequent areas of hypoechogenicity in ultrasonography, a well-marginated, hypervascular tumor with cystic areas of low-attenuation on contrast-enhanced CT^3,8. Smaller tumors are more likely to show homogeneous attenuation and they can be sharply marginated, as compared to larger ones, demonstrating a rupture of vascular trauma due to the neoplasia and tumoral necrosis^4,6,8.

The majority paragangliomas follow a benign clinical course. However, long-term follow-up studies suggest that the incidence of malignancy may be higher than suspected, especially in certain locations. The treatment of choice for paraganglioma is surgical resection⁸. In this series, the pancreatoduodenectomy occurred in 4 out of the 14 cases, because the lesion proximity to major vessels or the technical impossibility of surgical enucleation⁶. The other patients showed an equally good outcome after simple tumor enucleation⁸. In general, the resection of paragangliomas of the pancreas is technically difficult due to the possibility of a sudden catecholamine release during the operation. Furthermore, this lesion seems to grow slowly and long-term survival can be expected, even when metastasis is present².

REFERENCES

Recebido para publicação: 09/03/2009

Aceito para publicação: 17/08/2009

Fonte de financiamento: não há

Conflito de interesses: não há

• 1. Callender GG, Rich TA, Perrier ND. Multiple endocrine neoplasia syndromes. Surg Clin N Am 2008;88:863-95
• 2. Fujino Y, Nagata Y, Ogino K, Watahiki H, Ogawa H, Saitoh Y. Nonfunctional paraganglioma of the pancreas: report of a case. Surg Today 1998;28:209-12
• 3. Kim SY, Byun JH, Choi G, Yu E, Choi EK, Park SH, Lee MG. Korean J Radiol 2008;9:S18-21
• 4. Ohkawara T, Naruse H, Takeda H, Asaka M. Primary paraganglioma of the head of pâncreas: contribution of combinatorial image analyses to the diagnosis of disease. Internal Medicine 2005;44:1195-96
• 5. Paik KY. Paraganglioma of the pancreas metastasized to the adrenal gland: a case report. Korean J Gastroenterol 2009;54:409-412
• 6. Parithivel VS, Niazi M, Malhotra AK, Swaminathan K, Kaul A, Shah AK. Paraganglioma of the pancreas: literature review and case report. Digestive Diseases and Sciences 2000;45:438-41
• 7. Perrot G, pavic M, Milou F, Crozes C,Faucompret S, Vincent E. Difficult diagnosis of a pancreatic paraganglioma. La revue de medicine interne 2007;28:701-04
• 8. Tsukada A, Ishizaki Y, Nobukawa B, Kawasaki S. Paraganglioma of the pancreas: a case report and review of the literature. Pancreas 2008;36:214-15

Publication Dates

• Publication in this collection
  19 Jan 2011
• Date of issue
  Dec 2010