Sir,

Schwannoma of the pancreas is an extremely rare lesion;only 29 cases have been reported in the present era [1, 4,6]. In the literature, pancreatic schwannomas are report-ed as often showing cystic features, clinically mimickingpseudocysts or cystic tumors. Ancient schwannoma is avariant of schwannoma displaying pronounced degenera-tive changes; these include cyst formation, calcification,hemorrhage, hyalinization, and xanthomatous infiltration[3]. Degenerative nuclear atypia is also noted. Accordingto a PubMeD search, ancient pancreatic schwannoma hasnot been previously reported. We report a case of ancientschwannoma of the pancreas mimicking a cystic tumor.A 63-year-old previously healthy woman presented witha 6-month history of upper abdominal discomfort. A per-tinent physical examination revealed a large mass in theleft upper quadrant. All laboratory data were normal, in-cluding tumor markers. An abdominal computed tomog-raphy (CT) revealed a 10-cm multicystic mass in the tailof the pancreas (Fig. 1A), which was suspected to be acystic tumor of the pancreas. A distal pancreatectomywith a splenectomy was performed. The resected tail ofthe pancreas contained a 10.5×10×9 cm mass that waswell demarcated and partially covered by stretched butotherwise normal pancreatic parenchyma. The cut sur-faces of the mass showed a well-circumscribed, septate,cystic mass with a thick fibrous capsule (Fig. 1B). The

cystic areas were filled with old and new hemorrhage.Microscopically, the tumor was surrounded by thick fibrous tissue and normal pancreatic parenchyma(Fig. 2A). The peripheral portion of the mass was par-tially solid and composed of sheets of spindle cells thatoccasionally formed interlacing fascicles. The spindlecells had twisted nuclei and occasional vacuolar cyto-plasm (Fig. 2B). Some of the tumor cells showed nuclearatypia, but lacked mitotic figures. Most of the tumorshowed extensive degenerative changes, including cystformation, hemorrhage, and perivascular hyalinization(Fig. 2C). The tumor was abundantly infiltrated by his-tiocytes and siderophages. The tumor also had depositsof cholesterol in clefts and calcification in the degenera-tive areas. Immunostains showed the tumor cells to bestrongly and diffusely positive for S-100 protein(DAKO, USA) and vimentin (DAKO, USA) (Fig. 2D).There was no positive staining for actin (DAKO, USA)or for CD34 (Novocastra, UK). The tumor was diag-nosed as an ancient schwannoma of the pancreas. After 6months of follow-up, the patient had no specific com-plaints regarding this disorder.

In the literature, only 29 cases of intrapancreaticschwannoma have been previously reported [1, 4, 6].These 29 cases demonstrated that schwannoma of thepancreas is a tumor generally found in older adults, in anearly equal ratio of men to women. The majority of tu-mors are located in the body of the pancreas, but a fewhave been present in the head or tail. In all instances, asimple excision was adequate where this was technicallyfeasible. In our case, the patient was a 63-year-old wom-an, and the tumor was located in the tail of the pancreas.Upon follow-up 6 months after the excising the mass, thepatient was doing well.

The group of nonepithelial tumors of the pancreaswith spindle cell features can have a histopathologic re-semblance to pancreatic schwannoma. Leiomyoma andsolitary fibrous tumor have to be differentiated from pan-creatic schwannoma [5]. The tumor of our case showedimmunohistochemical reactivity for S-100 protein, rulingout leiomyoma and solitary fibrous tumor.

J.S. Lee (✉ ) · H.S. Kim · J.J. JungDepartment of Pathology, Seonam University, College of Medicine, 720 Kwangchi-Dong Namwon, Chollabuk-Do, 590-711, Koreae-mail: jshinlee@hanmail.netTel.: +82–63–620–0352, Fax: +82–63–620–0355

S.W. HanDepartment of Internal Medicine, Seonam University, College of Medicine, Namwon, Korea

Y.B. KimDepartment of General Surgery, Seonam University, College of Medicine, Namwon, Korea

Virchows Arch (2001) 439:697–699DOI 10.1007/s004280100492

L E T T E R T O T H E E D I T O R

Ji Shin Lee · Hyung Seok Kim · Jong Jae Jung Sang Woo Han · Young Bog Kim

Ancient schwannoma of the pancreas mimicking a cystic tumor

Received: 30 March 2001 / Accepted: 28 May 2001 / Published online: 7 August 2001© Springer-Verlag 2001

Fig. 1 A computed tomogra-phy (CT) scan (A) and cut sur-face of the mass (B). The CTscan shows a 10-cm multicysticmass in the tail of the pancreas.Grossly, the tumor is well de-marcated and covered by thickfibrous tissues and normal pan-creatic parenchyma. There isextensive cyst formation andhemorrhage

Fig. 2A–D Microscopic and immunohistochemical findings. The tu-mor, which is surrounded by fibrous tissues and normal pancreatic pa-renchyma (A, hematoxylin-eosin, original magnification ×20), is par-tially composed of spindle cells that have twisted nuclei and vacuolat-ed cystoplasm (B, hematoxylin-eosin, original magnification ×200).

The tumor has cyst formation, hemorrhage, and perivascular hyalin-ization (C, hematoxylin-eosin, original magnification ×100). The tu-mor displays an intensely positive reaction for S-100 protein, whereasthe surrounding pancreatic duct fails to react (D, anti-S-100 protein,avidin-biotin-immunoperoxidase, original magnification ×40)

sidered as one possibility in the differential diagnosis ofcystic masses in the pancreas.

References

1. Brown SZ, Owen DA, O’Connell JX, Scudamore CH (1998)Schwannoma of the pancreas: a report of two cases and a re-view of the literature. Mod Pathol 11: 1178–1182

2. Dahl I (1977) Ancient neurilemmoma (schwannoma). Acta Pathol Microbiol Scand [A] 85: 812–818

3. Enzinger FM, Weiss SM (1995) Benign tumors of peripheralnerves. In: Enzinger FM, Weiss SM (eds) Soft tissue tumors.Mosby Year Book, St. Louis, pp 821–888

4. Hsiao WC, Lin PW, Chang KC (1998) Benign retroperitonealschwannoma mimicking a pancreatic cystic tumor: case reportand literature review. Hepato-Gastroenterology 45: 2418–2420

5. Lüttges J, Mentzel T, Hübner G, Klöppel G (1999) Solitary fi-brous tumour of the pancreas: a new member of the small groupof mesenchymal pancreatic tumours. Virchows Arch 435:37–42

6. Morita S, Okuda J, Sumiyoshi K, Taketani M, Moriguchi A,Katsu K, Tanigawa N (1999) Pancreatic schwannoma: report ofa case. Surg Today 29: 1093–1097

699

Ancient schwannoma is a neurilemmoma that dis-plays pronounced degenerative changes [3]. A signifi-cant percentage of this tumor is located in deep struc-tures such as the retroperitoneum [2]. The degenerativechanges include cyst formation, calcification, hemor-rhage, and hyalinization. Degenerative nuclear atypia isalso another peculiar finding. According to the review ofthe literature of pancreatic schwannoma, approximatelytwo-thirds are partially cystic and some, particularly thelarger ones, can mimic a pancreatic pseduocyst or cysticpancreatic tumor in a radiographic examination [4]. Us-ing CT, the tumor mass in our patient was initially sus-pected to be a cystic tumor of the pancreas, but the mor-phological features are typical of ancient schwannomafound elsewhere in the body. A PubMeD search failed toreveal any reports of ancient schwannoma of the pancre-as. Thus, to the best our knowledge, this is the first re-port describing an ancient pancreatic schwannoma. De-finitive diagnosis of ancient pancreatic schwannoma wasonly established by pathological examination. It is sug-gested that ancient schwannoma of the pancreas be con-