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Solid and cystic tumor (SCT) of the pancreas predominantly Occurs in women, and the occurrence in men is extremely rare. We experienced a male case of $CT. A 38-year-old man was admitted with the complaint of upper abdominal pain. CT scan showed the presence of a mass in the head of the pancreas. The mass was composed of high density areas and low density areas. Ultrasonograms revealed the mass being composed of high echoic areas and low echoic areas.

Solid and cystic tumor (SCT) of the pancreas predominantly Occurs in women, and the occurrence in men is extremely rare. We experienced a male case of $CT. A 38-year-old man was admitted with the complaint of upper abdominal pain. CT scan showed the presence of a mass in the head of the pancreas. The mass was composed of high density areas and low density areas. Ultrasonograms revealed the mass being composed of high echoic areas and low echoic areas. The mass .was hypovascular on angiography. SCT was suspected and pancreaticoduodenectomy was performed. The cut surface of the tumor showed mainly cystic degenerative areas containing dark red hemorrhagic materials. Microscopically, there were solid areas in the periphery and pseudopapillary areas in the center. No metastasis was found in the removed lymph nodes. The tumor cells were not stained by Grimelius' silver stain. The tumor cells were positive for alpha-l-antitrypsin (AAT) and neuron-specific enolase (NSE). Pancreatic hormones such as insulin, glucagon, and somatostatin were all negative. Electron micrograph showed that tumor cells were rich in mitochondria. Zymogen granules and neurosecretory granules were not detected.

INTRODUCTION
Solid and cystic tumor (SCT) of the pancreas is a rare tumor characterized by its predominance in young women and a favorable prognosis. We experienced a male case of SCT of the pancreas. In this paper we reported the clinicopathological findings and sex hormone receptor contents in this tumor. Computed tomography (CT) scan showed the presence of a 5 x 5 cm well circumscribed mass in the head of the pancreas. The mass was composed of high density areas and low density areas with a partial rim of calcification. The pancreatic and bile duct were not dilated (Fig. 1). Ultrasonograms revealed a mass being composed of high echoic areas and low echoic areas in the pancreatic head (Fig. 2). Arteriography of the celiac artery demonstrated it as a hypovascular mass with stretched arterial branches of the pancreatic head arcade (Fig. 3). SCT of the pancreas was suspected and a laparotomy was performed on July 30, 1993. An encapsulated tumor was found in the head of the pancreas.
There was no evidence of metastases to the liver and lymph nodes macroscopically. Pancreaticoduodenectomy was performed with gross lymph node dissection. Postoperative course was uneventful, and the patient is alive without apparent recurrence two year and 11 months after operation.
Macroscopically, the tumor measured 5 x5.5 cm. The cut surface of the tumor showed mainly cystic degenerative areas containing dark red hemorrhagic materials. The tumor was surrounded by a fibrous capsule, as thick as 4 mm (Fig. 4). Microscopically, there were solid areas in the periphery and pseudopapillary areas in the center. The pseudopapillary areas consisted of fibrovascular stalks with centrally located capillaries and epithelial covering of several layers of neoplastic cells (Fig. 5a). The solid areas were composed of sheets of neoplastic cells with focal pseudorosette structures surrounding the FIGURE CT scan showed the presence of a mass in the head of the pancreas. The mass was composed of high density areas and low density areas with a partial rim of calcification.   (Fig. 5b). The fibrous capsule was not invaded by the neoplasm. No metastasis was found in the removed lymph nodes microscopically. The tumor cells were not stained by Grimelius' silver stain. The histological diagnosis was SCT of the pancreas.
Immunohistochemical studies were performed on formalin-fixed paraffin-embedded tissue by means of either the avidin-biotinperoxidase complex (ABC) technique or the peroxidase-antiperoxidase_. (PAP) technique. Antibodies used in this study were as follows: rabbit antihuman antibodies for neuron-specific enolase (NSE) (Nichirei Co., Ltd., Tokyo, Japan), rabbit antihuman antibodies for the pancreatic hormones such as insulin, glucagon, and somatostatin (Dako Corp., Santa Barbara, CA), biotingoat anti rabbit IgG (Dakopatts, Copenhagen, Denmark), peroxidase-conjugated streptoavidin (Dakopatts), goat antihuman antibodies for alpha-l-antitrypsin (AAT) (TAGO Co., Inc., Burlingame, CA), rabbit anti-goat serum protein (Dako Corp.), horseradish peroxidase (HRP)goat anti-HRP complex (Dako Corp.). Control staining was performed by replacement of the first antibody with nonimmune rabbit or goat sera. Sections of a normal pancreas were used as positive controls for the antisera against pan- FIGURE 4 The cut surface of the tumor showed mainly cystic degenerative areas containing dark red hemorrhagic materials. The tumor was surrounded by a fibrous capsule. creatic hormones. Most of the tumor cells were diffusely positive for AAT (Fig. 6a) and NSE (Fig. 6b). Pancreatic hormones such as insulin, glucagon, and somatostatin were all negative.
Electron microscopy was performed on formalin-fixed material which was post-fixed in 1% osmium tetroxide, embedded in Epon-812, and stained with uranyl acetate and lead citrate. Electron micrograph showed that tumor cells were rich in mitochondria. Zymogen granules and neurosecretory granules were not detected (Fig. 7).
Specimens for hormone-receptor analysis were obtained during surgery from the tumor mass. Samples were immediately frozen in liquid nitrogen and kept at -80C until sent to the Iwakuni Medical Laboratory (Yamaguchi, Japan). Estrogen receptor (ER) and progesterone receptor (PR) were assayed by the enzyme immunoassay (EIA) using monoclonal antibodies (Dainabot Co., Ltd., Tokyo, Japan). ER and PR contents in the tumor were less than 5.0 fmol/mg protein (normal value < 13) and less than 5.0 fmol/mg protein (normal value < 10), respectively.

DISCUSSION
Frantz [1] initially reported the pancreatic tumor that occurred predominantly in young women with a favorable prognosis as "papillary tumor of the pancreas" in 1959. Since then, several synonyms have appeared for this tumor [2][3][4][5][6][7][8][9][10][11]. The name of "solid and cystic tumor (SCT)" called by K16ppel and Morohoshi [12] is widely accepted in our country (Tab. I). K16ppel et al. [6] observed positive reaction for alpha-l-antitrypsin (AAT) by immunohistochemistry and zymogen granules by electron microscopy, and they thought that the tumor was of acinar cell origin, and at first named it as "solid and cystic acinar cell tumor" in 1981. Neurosecretory granules were observed in the cytoplasm of this tumor by Schlosnagle et al. [7]. However, some investigators reported that there were neither zymogen nor neurosecretory granules in the cytoplasm of this tumor [2,4,5,8,11]. Neuron-specific enolase (NSE) was found in the tumor by Chott et al. [13]. Morohoshi et al. [12] emphasized that AAT did not serve as a specific marker for acinar cell tumors, and later corrected the name to "solid and cystic tumor (SCT)" in 1984. The histogenesis of this tumor has not been completely clarified, but it is suspected that this tumor is derived from primordial cells that can differentiate to acinar cell, ductal cells, or endocrine cells [11]. Anyhow, the clinicopathological findings of our male case agree with previously reported findings of SCT in women.
SCT predominantly occurs in women, and the occurrence in men is extremely rare. In Japanese literature that included 126 cases, only 10 patients (7.9%) were males [14]. Because of this predominant occurrence of SCT in women, some investigators thought that hormonal factors might play a role in its pathogenesis (Tab. II).
Ladanyi et al. [15] found a definite increase in both ER and PR in this tumor. Wrba et al. [16] demonstrated negativity for ER but strong positivity for PR. Carbone et al. [17] found high levels of type II ER, while type I ER were absent or present at very low levels. However, ER was not detected by Miettinen et al. [18]. Neither ER nor PR were found by Katz et al. [19], and Pettinato et al. [20]. K16ppel et al. [21] examined Taxy (1976) [3] Boor (1979) [4] Compagno (1979) [51 K16ppel (1981) [6] Schlosnagle (1981)  Ladanyi [15] Wrba [16] Carbone [17] Miettinen [18] Katz [19] Pettinato [20] K16ppel [21] Present study 18 Less than 5.0 fmol/mg protein Less than 5.0 fmol/mg protein ER and PR in SCT of male patients using paraffin-embedded specimens, and did not detect ER and PR. There exists little literature on examining ER and PR using fresh frozen specimens in SCT of male patients. In this study, we assayed ER and PR in SCT of a male patient by EIA using fresh frozen specimens, and demonstrated that both ER and PR were negative. Our results support the results by K16ppel et al. Estrogen and progesterone may not play a role in the pathogenesis of SCT.
The treatment of SCT is complete resection of the tumor. Panceaticoduodenectomy for lesions of the head of the pancreas and distal pancreatectomy for lesions of the body and tail of the pancreas should be performed. The prognosis after complete resection is favorable. However, this tumor should be considered as a low-grade malignancy because liver metastasis, lymph node metastasis, and peritonitis carcinomatosa have been reported [22][23][24][25].