Hippokratia 2013, 17(1):68-72
Huang Y1, Feng JF2
1Nursing Department, 2Department of Oncological Surgery, Zhejiang Cancer Hospital, Hangzhou, China
Background and aim: Solid pseudopapillary tumor (SPT) of the pancreas is a very rare neoplasm of low malignant potential that mostly affects young women. The aim of the present study is to report our experience in surgical treatment of SPT and review of the literature.
Material and methods: A retrospective review of three cases of SPT who were treated at our department during the last two years was performed. The clinicopathologic characteristics, surgical treatment, and prognosis are described in detail.
Results: Case 1 described an asymptomatic SPT in a pregnant woman. To the best of our knowledge, only one case of SPT in pregnancy has been reported in the literature. Case 2 described an SPT in the pancreatic tail causing splenic infarction, and a distal pancreatectomy combined with splenectomy was performed. Case 3 described an SPT in the pancreatic head, for which a pancreatoduodenectomy was successfully performed. All of the three patients were followed up for 10-22 months without recurrence or metastases after the initial surgery at the time of reporting.
Conclusions: At present, radical resection is the treatment of choice for SPT. Enucleation can be performed for tumors with complete amicula. Distal pancreatectomy combined with or without splenectomy can be performed for pancreatic body and/or tail tumor, and pancreatoduodenectomy for pancreatic head tumor. The prognosis of SPT is good.
Key words: solid pseudopapillary tumor, pancreatic neoplasm, treatment
Corresponding author:Ji-Feng Feng, MD, Department of Oncological Surgery, Zhejiang Cancer Hospital, No.38 Guangji Road, Hangzhou 310022, China, tel: +86-0571-88122038, e-mail: Fengjif@163.com
Solid pseudopapillary tumor (SPT) of the pancreas, first reported by Frantz et al1 in 1959, is an uncommon but distinct pancreatic neoplasm, accounting for 1%-2% of all pancreatic tumors2-4. The tumor has been given several different names according to its macroscopic and microscopic character until this name, solid pseudopapillary tumor of the pancreas, was defined by the World Health Organization (WHO) as unique tumor in 19965. In this paper, we report our experience in surgical treatment of SPT and review the literature.
A 26 year-old female in the 14th week of pregnancy was admitted to our department with abdominal mass accidently detected by ultrasonography (US) in prenatal care. US revealed a well-circumscribed inhomogenous mass (9.5 × 6.2 × 9.0 cm) with intact amicula (Figure 1A). Magnetic resonance imaging (MRI) was performated to verify a giant solid-cystic mass with T1- and T2- weighted images in the right of pancreatic head (Figure 1B-C). FIne needle aspiration biopsy (FNAB) showed that tumor cells were composed of papillary structures, with lots of neoplastic epithelial cells, polygonal in form. At laparotomy, successful tumor enucleation was performed. Microscopically, the pancreatic tumor showed marked cellular proliferation in the solid areas that alternated with a pseudopapillary and cystic pattern (Figure 1D). Immunohistological results revealed that the tumor cells were positive for Vimentin (Vim), Cytokeratin (CK), Synaptophysin (Syn), Neuron specific enolase (NSE), CD56, and CD10. On the 3rd postoperative day, pancreatic fistual occurred. US detected a local opaque dark area of fluid measuring about 52mm × 32mm in the upper middle abdomen (Figure 1E). Fetal position was good (Figure 1F). On the 25th postoperative day, the abdominal drainage tube was removed because the liquid less than 5ml. After 28 days of hospital stay, she was discharged in good general condition. On the 38th week, a healthy, mature girl with an Apgar score 9/10 was born with cesarean section.
Figure 1: US revealed a well-circumscribed inhomogenous mass with intact amicula in the right of pancreatic head (A). MRI was performated to verify a giant solid-cystic mass with T1- and T2- weighted images in the right of pancreatic head (B-C). The pancreatic tumor showed marked cellular proliferation in the solid areas that alternated with a pseudopapillary and cystic pattern (D). US detected a local opaque dark area of fluid in the upper middle abdomen (E). Fetal position was good (F).
A 18-year-old female was admitted to our department with abdominal pain for four days. US revealed a well-circumscribed inhomogenous mass measuring about 4.5 × 3.9 cm between the spleen and left kidney (Figure 2A-B). Computed tomography (CT) demonstrated a predominantly cystic, well-encapsulated mass with a CT value of 26 Hounsfield Units (HU), measuring about 4.2 ×3.8 cm, in the pancreatic tail, causing splenic infarction (Figure 2C). After contrast injection, the solid part of the tumor showed moderate to strong enhancement (Figure 2D). At laparotomy, a distal pancreatectomy combined with splenectomy was successfully performed. Microscopically, the tumor showed proliferation in solid areas that alternates between a pseudopapillary and cystic pattern (Figure 2E). The immunohistological results revealed that the tumor cells were positive for Vim, Syn, CD56, and CD10. She was followed up for 22 months without recurrence or metastases after the initial surgery at the time of reporting (Figure 2F).
Figure 2: US revealed a well-circumscribed inhomogenous mass between the spleen and left kidney (A-B). CT demonstrated a predominantly cystic, well-encapsulated mass in the pancreatic tail causing splenic infarction (C). After contrast injection, the solid part of the tumor showed moderate to strong enhancement (D). The tumor showed proliferation in solid areas that alternates between a pseudopapillary and cystic pattern (E). The patient was followed up for 22 months without recurrence or metastases (F).
A 38-year-old female was admitted to our department with abdominal pain for two months. Abdominal CT revealed a low-density mass with a CT value of 26 HU, measuring about 1.9×3.2 cm, in the pancreatic head (Figure 3A-B). At exploration, the tumor was located in the pancreatic head. A pancreatoduodenectomy was successfully performed. The histologic appearance varied in different regions of the tumor. Solid areas consisted of sheets and cords of round to ovoid cytologically bland cells arranged around a delicate fibrovascular septa (Figure 3C). Immunohistological results revealed that the tumor cells were positive for Vim, Syn, NSE, CD56, and CD10. She was followed up for 10 months without recurrence or metastases (Figure 3D).
Figure 3: CT revealed a lowdensity mass in the pancreatic head (A-B). Solid areas consist of sheets and cords of round to ovoid cytologically bland cells arranged around a delicate fibrovascular septa (C). The patient was followed up for 10 months without recurrence or metastases (D).
The cellular origin of SPT is unclear and might involve ductal cells, acinar cells, endocrine cells or multipotential stem cells.3 The pathogenesis of SPT has not been revealed yet, however, the disease is generally considered to have a benign course with low malignant potential, usually affecting young women in their second or third decade of life3,4. There is a female preponderance of SPT with a female-to-male ratio of 9.78:1, although rare cases have been reported in men2-4,6. Tien et al7 showed that there were no gender-specific trends in expression of sex hormone receptor protein or clinicopathologic characteristics.
SPT was classified according to the WHO criteria as either an SPT with an uncertain potential for malignancy or as a solid pseudopapillary carcinoma (SPC)8.Criteria that could distinguish potentially malignant tumors, classified as SPC, included the following: 1) perineural invasion, 2) angioinvasion, 3) deep invasion into the surrounding tissue, and 4) distant metastases. Postoperatively, patients were further classified using the American Joint Committee on Cancer (AJCC)/International Union Against Cancer (UICC) tumor node metastasis (TNM) classification system: R0 (no residual tumor), R1 (microscopic residual tumor), or R2 (macroscopic residual tumor) 9.
The malignant potential of SPT is reported to be 10%-15%.4 The most common sites of metastases are the liver, regional lymph nodes, mesentery, omentum, and peritoneum10. Local invasion may involve adjacent organs, including the duodenum, spleen, portal vein, superior mesenteric vein, and bile duct; lymph node metastasis also has been reported 11,12.Washington13 showed that the clinicopathologic characteristics of SPT, including diffuse growth, venous invasion, nuclear pleomorphism, mitotic rate, necrosis and dedifferentiation, are related to its aggressive behavior or metastatic potential. Yang et al14 showed the high proliferative index assessed by immunohistochemical staining for Ki-67 may predict poor outcome of malignant SPT.
The initial presentations of SPT are usually nonspecific. It is a non-functional, slow-growing neoplasm that very often reaches considerable size before the first symptoms appear4,6,15,16. SPT often demonstrates peripheral artery enhancement and central calcification. Papavramidiset al4 summarized 718 SPT patients in the literature, showing upper abdominal pain is the most common symptom (46.5%), followed by a slowly enlarged, palpable, and non-tender abdominal mass (34.8%). Asymptomatic cases are reported in 15.5%. Differential diagnosis includes disoncogenetic cysts, pseudocysts, hydatid cysts, and cystic tumors, such as cystadenoma, cystadenocarcinoma, microcystic adenoma, lymphangioma, various forms of sarcomas, cystic islet cell tumors, and acinar cell cystadenocarcinomas.
Accurate preoperative diagnosis of SPT is difficult because of the similarity of the findings among cystic lesions of the pancreas4,6. As part of the general investigation, US shows a well-circumscribed inhomogenous mass in the epigastrium. Following US, CT usually shows heterogeneous enhancement with progressive central filling and late enhancement of the capsule4,17. If MRI reveals an encapsulated mass with solid and cystic components as well as hemorrhage without obvious internal septum, SPT should be highly suspected18. Although some image characteristics are suggestive of SPT, FNAB can be used to obtain a possible preoperative histological diagnosis19. However, some researchers have suggested that FNAB should be avoided because of the potential risk of tumor spillage20,21. In our case series, FNAB was performed in one case for the patient with pregnancy. We concluded that the FNAB was safe in SPT patient with pregnancy.
Microscopically, the growth pattern of the tumor cells is remarkably uniform, with a combination of solid, pseudopapillary, or hemorrhagic pseudocystic structures in various proportions22. The tumor contains a mixture of solid, cystic, and pseudopapillary patterns in various proportions. In immunohistological results, the tumor cells are diffusely positive for Vim in all tumors, most cases express diffuse positive staining for NSE, some of which are focally positive for CK and SYN, and few positive for S-100 protein3,4,22. Notohara et al23 found that SPT exhibited unique immunohistochemical features with expression of CD56, CD10, and these results are diagnostically useful. In our case series, the immunohistological results were shown in Figure 4. Based on these histological findings, the final diagnosis of SPT was confirmed. Recently, immunoreactivity for ß-catenin is found in the cytoplasm and the nuclei of almost all tumor cells in the majority of SPT4,24,25. Loss of membrane staining and/or nuclear staining for E-cadherin is seen in 100% of cases of SPT of the pancreas26.
Figure 4: Immunohistological results revealed the tumor cells were positive for Vim (A), CK (B), Syn (C), NSE (D), CD56 (E), and CD10 (F) (200×).
At present, radical resection is the treatment of choice for SPT even with metastasis or local extension2-4,16,27. Local resection or enucleation can be performed for small tumors with complete amicula. Distal pancreatectomy combined with or without splenectomy can be performed for pancreatic body and/or tail tumor, and pancreatoduodenectomy for pancreatic head tumor. Complete surgical excision is curative in greater than 95% of patients with SPT limited to the pancreas28. The low grade of malignancy of this tumor, and because the mass is usually surrounded by a dense fibrous capsule, led some surgeons, especially for children, to perform simple enucleation of the neoplasm6,29,30. Invasion to the portal vein or superior mesenteric artery should not be included as a criterion for nonresectability of these pancreatic neoplasms4,28. For the metastases, there is also general consensus that surgical debulking should be performed2,4,28,30. In general, SPT can be removed laparoscopically because they are generally benign and have thick fibrous capsules. However, the decision to perform laparoscopic surgery should be made carefully to avoid the risk of rupture31,32. The role of chemotherapy and radiotherapy in treatment of SPT is poorly defined at present, since only few reports are available on them33,34.
The prognosis of SPT patients even with local recurrence and metastasis or invasion is good. It has been reported that the overall 5-year survival rate of SPT patients is about 95%4. Due to the favorable prognosis and long survival rate of SPT patients with local recurrence or metastasis, it is difficult to identify the predictive factors for their survival time. Recurrence, local invasion, and limited metastasis are not the contraindications for resection, and some patients with unresectable SPT may also have a long survival time4,16,27,35. In our case series, all of the three patients were followed up for 10-22 months, without recurrence or metastases after the initial surgery at the time of reporting. Kim et al36 reported that most SPT patients who developed recurrence had metastases at the first operation, tumor rupture, or adjacent organ invasion. Because recurrence was rare, however, statistically meaningful risk factors associated with recurrence could not be determined.
In conclusion, radical resection is the treatment of choice for SPT. Enucleation can be performed for tumors with complete amicula in pregnancy. Distal pancreatectomy combined with or without splenectomy can be performed for pancreatic body and/or tail tumor, and pancreatoduodenectomy for pancreatic head tumor. The prognosis of SPT is good.
Conflict of interest
The authors declare no conflicts of interest.
1. Frantz VK. Tumors of the pancreas. In: Atlas of tumor pathology. Armed forces Institute of Pathology, Washington DC, 1959, 32-33.
2. Martin RC, Klimstra DS, Brennan MF, Conlon KC. Solid-pseudopapillary tumor of the pancreas: a surgical enigma? Ann Surg Oncol. 2002; 9: 35-40.
3. Klimstra DS, Wenig BM, Heffess CS. Solid-pseudopapillary tumor of the pancreas: a typically cystic carcinoma of low malignant potential. Semin Diagn Pathol. 2000; 17: 66-80.
4. Papavramidis T, Papavramidis S. Solid pseudopapillary tumors of the pancreas: review of 718 patients reported in English literature. J Am Coll Surg. 2005; 200: 965-972.
5. Kloppel G, Solcia E, Longnecker DS, Capella C, Sobin LH. Histological typing of tumors of the exocrine pancreas. In: World Health Organisation. International histological classification of tumors. 2nd edition. Springer, Berlin, Heidelberg, New York, 1996, 120-128.
6. Lam KY, Lo CY, Fan ST. Pancreatic solid-cystic-papillary tumor: clinicopathologic features in eight patients from Hong Kong and review of the literature. World J Surg. 1999; 23: 1045-1050.
7. Tien YW, Ser KH, Hu RH, Lee CY, Jeng YM, Lee PH. Solid pseudopapillary neoplasms of the pancreas: is there a pathologic basis for the observed gender differences in incidence? Surgery. 2005; 137: 591-596.
8. Klppel G, Luttges J, Klimstra DS. Solid-pseudopapillary neoplasm. In: Hamilton SR, Aaltonene LA, editors. World Health Organization classification of tumors: pathology and genetics of tumors of the digestive system. IARC Press, Lyon, France, 2000, 246-248.
9. Wittekind C, Compton CC, Greene FL, Sobin LH. TNM residual tumor classification revisited. Cancer. 2002; 94: 2511-2516.
10. Tang LH, Aydin H, Brennan MF, Klimstra DS. Clinically aggressive solid pseudopapillary tumors of the pancreas: a report of two cases with components of undifferentiated carcinoma and a comparative clinicopathologic analysis of 34 conventional cases. Am J Surg Pathol. 2005; 29: 512-519.
11. Martin RC, Klimstra DS, Brennan MF, Conlon KC. Solid pseudopapillary tumor of the pancreas: a surgical enigma? Ann Surg Oncol .2002; 9: 35-40.
12. Adamthwaite JA, Verbeke CS, Stringer MD, Guillou PJ, Menon KV. Solid pseudopapillary tumour of the pancreas: diverse presentation, outcome and histology. JOP. 2006; 7: 635-642.
13. Washington K. Solid-pseudopapillary tumor of the pancreas: challenges presented by an unusual pancreatic neoplasm. Ann Surg Oncol. 2002; 9: 3-4.
14. Yang F, Jin C, Long J, Yu XJ, Xu J, Di Y, et al. Solid pseudopapillary tumor of the pancreas: a case series of 26 consecutive patients. Am J Surg. 2009; 198: 210-215.
15. Madan AK, Weldon CB, Long WP, Johnson D, Raafat A. Solid and papillary epithelial neoplasm of the pancreas. J Surg Oncol. 2004; 85: 193-198.
16. de Castro SM, Singhal D, Aronson DC, Busch OR, van Gulik TM, Obertop H, et al. Management of solid-pseudopapillary neoplasms of the pancreas: a comparison with standard pancreatic neoplasms. World J Surg. 2007; 31: 1130-1135.
17. Coleman KM, Doherty MC, Bigler SA. Solid-pseudopapillary tumor of the pancreas. Radiographics. 2003; 23: 1644-1648.
18. Yu CC, Tseng JH, Yeh CN, Hwang TL, Jan YY. Clinicopathological study of solid and pseudopapillary tumor of pancreas: emphasis on magnetic resonance imaging findings. World J Gastroenterol. 2007; 13: 1811-1815.
19. Pelosi G, Iannucci A, Zamboni G, Bresaola E, Iacono C, Serio G. Solid and cystic papillary neoplasm of the pancreas: a clinico-cytopathologic and immunocytochemical study of five new cases diagnosed by fine-needle aspiration cytology and a review of the literature. Diagn Cytopathol. 1995; 13: 233-246.
20. Petrakis I, Vrachassotakis N, Kogerakis N, Hatzidakis A, Zoras O, Chalkiadakis G. Solid pseudopapillary neoplasm of the pancreas: report of a case after a 10-year follow-up and review of the literature. Pancreatology. 2001; 1:123-128.
21. Panieri E, Krige JE, Bornman PC, Graham SM, Terblanche J, Cruse JP. Operative management of papillary cystic neoplasm of the pancreas. J Am Coll Surg. 1998; 186: 319-324.
22. Kosmahl M, Seada LS, Jänig U, Harms D, Klöppel G. Solid-pseudopapillary tumor of the pancreas: its origin revised. Virchows Arch. 2000; 436: 473-480.
23. Naresh KN, Borges AM, Chinoy RF, Soman CS, Krishnamurthy SC. Solid and papillary epithelial neoplasm of the pancreas. Diagnosis by fine needle aspiration cytology in four cases. Acta Cytol. 1995; 39: 489-493.
24. Liu BA, Li ZM, Su ZS, She XL. Pathological differential diagnosis of solid-pseudopapillary neoplasm and endocrine tumors of the pancreas. World J Gastroenterol. 2010; 16: 1025-1030.
25. Tanaka Y, Kato K, Notohara K, Hojo H, Ijiri R, Miyake T, et al. Frequent beta-catenin mutation and cytoplasmic/nuclear accumulation in pancreatic solid-psudopapillary neoplasm. Cancer Res. 2001; 61: 8401-8404.
26. Chetty R, Serra S. Nuclear E-cadherin immunoexpression: from biology to potential applications in diagnostic pathology. Adv Anat Pathol. 2008; 15: 234-240.
27. Notohara K, Hamazaki S, Tsukayama C, Nakamoto S, Kawabata K, Mizobuchi K, et al. Solid-pseudopapillary tumor of the pancreas. Immunohistochemical localization of neuroendocrine markers and CD10. Am J Surg Pathol. 2000; 24: 1361-1371.
28. Jeng LB, Chen MF, Tang RP. Solid and papillary neoplasm of the pancreas. Emphasis on surgical treatment. Arch Surg. 1993; 128: 433-436.
29. Wünsch LP, Flemming P, Werner U, Gluer S, Bürger D. Diagnosis and treatment of papillary cystic tumor of the pancreas in children. Eur J Pediatr Surg. 1997; 7: 45-47.
30. Reddy S, Cameron JL, Scudiere J, Hruban RH, Fishman EK, Ahuja N, et al. Surgical management of solid-pseudopapillary neoplasms of the pancreas (Franz or Hamoudi tumors): a large single-institutional series. J Am Coll Surg. 2009; 208: 950-957.
31. Fais PO, Carricaburu E, Sarnacki S, Berrebi D, Orbach D, Baudoin V, et al. Is laparoscopic management suitable for solid pseudo-papillary tumors of the pancreas? Pediatr Surg Int. 2009; 25: 617-621.
32. Cavallini A, Butturini G, Daskalaki D, Salvia R, Melotti G, Piccoli M, et al. Laparoscopic pancreatectomy for solid pseudo-papillary tumors of the pancreas is a suitable technique; our experience with long-term follow-up and review of the literature. Ann Surg Oncol. 2011; 18: 352-357.
33. Rebhandl W, Felberbauer FX, Puig S, Paya K, Hochschorner S, Barlan M, et al. Solid-pseudopapillary tumor of the pancreas (Frantz tumor) in children: report of four cases and review of the literature. J Surg Oncol. 2001; 76: 289-296.
34. Matsunou H, Konishi F. Papillary-cystic neoplasm of the pancreas: a clinicopathologic study concerning the tumor aging and malignancy of nine cases. Cancer. 1990; 65: 283-291.
35. Mao C, Guvendi M, Domenico DR, Kim K, Thomford NR, Howard JM. Papillary cystic and solid tumors of the pancreas: a pancreatic embryonic tumor? Studies of three cases and cumulative review of the world’s literature. Surgery. 1995; 118: 821-828.
36. Kim CW, Han DJ, Kim J, Kim YH, Park JB, Kim SC. Solid pseudopapillary tumor of the pancreas: can malignancy be predicted? Surgery. 2011; 149: 625-634.