•
Ultrasound
Ultrasonic Characteristics of Cystadenoma of the Pancreas 1 Alan H. Wolson, M.D., and William J. Walls, M.D. The authors describe the ultrasound appearance of cystadenoma of the pancreas. Such lesions may be characterized as sonolucent, with good through-transmission, slightly irregular but well-defined margins, and internal echoes from septa. INDEX TERMS: Pancreas, neoplasms. Pancreas, ultrasound Radiology 119:203-205, April 1976
•
•
A LTHOUGH THE value of ultrasound in the diagnosis .K of pancreatic disease such as pancreatitis, pseu-
cystadenoma (Fig. 3). At surgery, a modified Whipple procedure was performed with removal of both the duodenum and the pancreatic mass, which proved to be a cystadenoma.
docyst, and carcinoma has been discussed previously (2-5, 7, 9-12), we know of no other report describing the ultrasound findings in pancreatic cystadenoma with the exception of a single case mentioned by Stuber et a/. (10). Although this is an uncommon lesion, we have seen 3 patients with proved cystadenoma and all had a similar ultrasonic appearance.
CASE III (N. S.): A 75-year-old white woman was admitted for evaluation of back and rib pain which had persisted for nine months. Twelve years earlier she had been treated for diffuse osteoporosis and multiple compression fractures of the spine, and an upper gastrointestinal series and barium enema study were normal at that time. In addition to back pain, she now complained of a weight loss of 2 kg (5 lb.), anorexia, and weakness. Physical examination revealed muscle wasting, hepatomegaly, and dilated abdominal veins. Excretory urography demonstrated a large mass displacing the left kidney downward. An ultrasound examination showed a large, sonolucent septate mass (Fig. 4), and angiography revealed that it was a highly vascular lesion supplied by pancreatic vessels, exhibiting the typical appearance of a cystadenoma of the pancreas. The patient's condition precluded surgery, and she was treated medically.
CASE REPORTS CASE I (L. C.): A 32-year-old white woman was admitted on July 15, 1974 for evaluation of a hard, nontender mass in the left upper quadrant, first detected by the patient two weeks earlier. She had no other medical complaints. Examination revealed a large mass in the left upper quadrant, which was believed to be an enlarged spleen. A radionuclide study of the liver and spleen was normal. Excretory urography revealed that the mass was anterior to the kidney and did not arise from it. An ultrasound study revealed a large, sonolucent septate mass displacing the left kidney posteriorly (Fig. 1). An upper gastrointestinal series showed an extrinsic pressure defect on the greater curvature of the stomach and displacement of loops of the jejunum. The barium enema study was unremarkable except for a low splenic flexure. At surgery an 8-cm cystic mass was resected along with the spleen. The final diagnosis was mucinous cystadenoma of the pancreas.
DISCUSSION
Cystadenoma of the pancreas is a relatively uncommon tumor. Only small series have been reported since 1971, when Lewis and Dormandy found a total of 251 cases in the literature (6). Most cystadenomas occur in women, primarily those 30 to 60 years of age. The great majority of patients have a palpable abdominal mass, most often in the body or tail of the pancreas although it may occur in the pancreatic head. The findings on plain films, excretory urograms, and barium studies are nonspecific, showing displacement of organs, extrinsic pressure defects in hollow visci, a softtissue mass, and sometimes calcifications. Angiography has generally been considered quite specific, showing a hypervascular mass supplied by displaced pancreatic vessels and frequently containing cystic (hypovascular) areas (1). Four cases have also been reported in which the entire lesion was relatively hypovascular and difficult to distinguish from a pancreatic pseudocyst (1, 8).
CASE II (M. R.): A 59-year-old white woman had had nausea, vomiting, diarrhea, and severe pain radiating to the back for several months prior to admission. She had lost 11 kg (25 lb.) and exhibited jaundice, dark urine, and acholic stools, though jaundice was not present at the time of admission. On physical examination, she appeared quite ill. An upper gastrointestinal series demonstrated a mass in the head of the pancreas, indenting the medial aspect of the duodenal loop, with displacement of the antrum of the stomach upward and to the left. No mucosal destruction was seen. An ultrasound study revealed a large sonolucent mass in the region of the head of the pancreas. Internal echoes were noted at lower gain and increased at higher gain; they suggested the presence of septa (Fig. 2). Angiography revealed a hypervascular mass characteristic of a
1 From the Departments of Radiology of the University of Michigan Medical Center, Ann Arbor, Mich. (A. H. W., Assistant Professor and Director of Ultrasound) and the University of Kansas Medical Center, Kansas City, Kan. (W. J. W., Assistant Professor). Accepted for publication in October 1975. sjh
203
204
ALAN
J.
WOLSON AND WILLIAM
t
a
I
! • t'
WALLS
April 1976
Fig. 1. CASE I. Sonolucent septate left-upperquadrant mass with well-defined but slightly irregular margins in both longitudinal (A) and transverse (C) sections. A longitudinal section at high gain (B) reveals increased irregularity of the margins and excellent through-transmission. CEPH = cephalad; ANT anterior; R right; CYST-AD cystadenorna. The longitudinal sections were made 3 cm to the left of the midline; the transverse section was made 6 cm below the xiphoid .
=
=
B
X-15
J.
X-15
=
.,. KG.
Fig. 2. CASE II. A-C. Echograms of the sonolucent septate right-upper-quadrant mass reveal well-defined, irregular margins (A and C). At high gain (B), there are filling in from the margins, more echoes from the septum, and good through-transmission. R = right; C, CYST-AD = cystadenoma; ANT anterior; CEPH cephalad. The transverse sections were made 15 cm below the xiphoid; the longitudinal section was made 2 cm to the right of the midline.
=
L+2
CYST-AD
=
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Ultrasound
Fig. 4. CASE III. Transverse section demonstrates a sonolucent septate lesion (c). The margins are welldefined and slightly irregular, andthere is through-transmission, ant = anterior; L = left. CONCLUSION
Fig. 3. CASE II. Theangiogram revealsa hypervascular lesion with avascular areas, characteristic of a cystadenoma. We have performed ultrasound examinations on 3 patients with abdominal masses which ultimately turned out to be pancreatic cystadenomas. To our knowledge, the ultrasound appearance of this lesion has not been reported previously. All 3 patients had well-defined, sonolucent lesions, in the tail of the pancreas in 2 (CASES I and III) and in the pancreatic head in one (CASE II). All tumors had well-defined but slightly irregular margins, good through-transmission, and internal echoes from septa. As gain wasincreased, additional internal echoes appeared in all cases. Angiography was performed in only 2 patients (CASES II and III); both had typical hypervascular lesions (Fig. 3). Surgical resection confirmed the diagnosis in 2 patients (CASES I and II), but one patient was too ill for surgery and the angiogram was the sole basis for the diagnosis. The presence of a well-defined sonolucent lesion in the area of the pancreas raises several diagnostic possibilities, including pseudocyst, focal pancreatitis, occasionally carcinoma of the pancreas, and rarely a homogeneous solid mass such as lymphoma (9). The 3 cases reported here indicate that cystadenoma should be added to this list. It would be difficult to distinguish a cystadenoma from a septate pseudocyst, although the latter is uncommon: pseudocysts do tend to have less irregular borders unless infection or hemorrhage has occurred, and they generally exhibit greater throughtransmission than cystadenomas. Focal pancreatitis may demonstrate internal echoes, but they are unlikely to take the form of septa (9). Some homogeneous solid lesions may cause difficulty, particularly lymphoma, which may appear cystic and have internal structures similar to septa. While some carcinomas of the pancreas do have a sonolucent appearance, they tend to fill in with echoes at lower gain and have less through-transmission than the cystadenomas we have seen.
Ultrasound is an important noninvasive method of detecting and evaluating pancreatic masses. Our experience suggests that pancreatic cystadenomas have a characteristic ultrasonic appearance. While other lesions may look similar, a sonolucent lesion with strong through-transmission, slight irregularity of the wall, and an internal septum should suggest cystadenoma, particularly in the absence of a history of pancreatitis. ADDENDUM: Since this paper was accepted, two additional cases have been seen at UMMC. Both patients had ultrasonic findings identical to the 3 cases reported here, and their condition was diagnosed using the criteria established above. Department of Radiology Division of Ultrasound University of Michigan Medical Center Ann Arbor, Mich. 48104 REFERENCES 1. Boijsen E: Pancreatic angiography. [In] Abrams HL, ed: Angiography. Boston, Little, Brown, 2d Ed, 1971, Chapt 60, pp 967-968 2. Engelhart G, Blauenstein UW: Ultrasound in the diagnosis of malignant pancreatic tumours. Gut 11:443-449, May 1970 3. Filly RA, Freimanis AK: Echographic diagnosis of pancreatic lesions. Ultrasound scanning techniques and diagnostic findings. Radiology 96:575-582, Sep 1970 4. Holm HH: Ultrasonic scanning in the diagnosis of spaceoccupying lesions of the upperabdomen. Br J Radiol 44:24-36, Jan 1971 5. Leopold GR: Pancreatic echography: a new dimension in the diagnosis of pseudocyst. Radiology 104:365-369, Aug 1972 6. LewisA, Dormandy J: Cystadenoma of the pancreas. A report of two cases. Br J Surg 58:420-422, Jun 1971 7. Kahn PC: Pancreatic echography. [In] Eaton SB Jr, Ferrucci JT Jr, ed: Radiology of the Pancreas and Duodenum. Philadelphia, Saunders, 1973,Chapt 9, pp 276-288 8. Pressman BD, Asch T, Casarella WJ: Cystadenoma of the pancreas. A reappraisal of angiographic findings. Am J Roentgenol 119:115-120, Sep 1973 9. Sokoloff J, Gosink BB, Leopold GR, et al: Pitfalls in the echographic evaluation of pancreatic disease. J Clin Ultrasound 2: 321-326, Dec 1974 10. Stuber JL, Templeton AW, Bishop K: Sonographic diagnosis of pancreatic lesions. Am J Roentgenol 116:406-412, Oct 1972 11. Templeton AW, Stuber JL: Abdominal and retroperitoneal sonography. Am J RoentgenoI113:741-748, Dec 1971 12. Walls WJ, Gonzalez G, Martin NL, et al: B-scan ultrasound evaluation of the pancreas. Advantages and accuracy compared to otherdiagnostic techniques. Radiology 114:127-134, Jan 1975
Ultrasound
Ultrasonic Characteristics of Cystadenoma of the Pancreas 1 Alan H. Wolson, M.D., and William J. Walls, M.D. The authors describe the ultrasound appearance of cystadenoma of the pancreas. Such lesions may be characterized as sonolucent, with good through-transmission, slightly irregular but well-defined margins, and internal echoes from septa. INDEX TERMS: Pancreas, neoplasms. Pancreas, ultrasound Radiology 119:203-205, April 1976
•
•
A LTHOUGH THE value of ultrasound in the diagnosis .K of pancreatic disease such as pancreatitis, pseu-
cystadenoma (Fig. 3). At surgery, a modified Whipple procedure was performed with removal of both the duodenum and the pancreatic mass, which proved to be a cystadenoma.
docyst, and carcinoma has been discussed previously (2-5, 7, 9-12), we know of no other report describing the ultrasound findings in pancreatic cystadenoma with the exception of a single case mentioned by Stuber et a/. (10). Although this is an uncommon lesion, we have seen 3 patients with proved cystadenoma and all had a similar ultrasonic appearance.
CASE III (N. S.): A 75-year-old white woman was admitted for evaluation of back and rib pain which had persisted for nine months. Twelve years earlier she had been treated for diffuse osteoporosis and multiple compression fractures of the spine, and an upper gastrointestinal series and barium enema study were normal at that time. In addition to back pain, she now complained of a weight loss of 2 kg (5 lb.), anorexia, and weakness. Physical examination revealed muscle wasting, hepatomegaly, and dilated abdominal veins. Excretory urography demonstrated a large mass displacing the left kidney downward. An ultrasound examination showed a large, sonolucent septate mass (Fig. 4), and angiography revealed that it was a highly vascular lesion supplied by pancreatic vessels, exhibiting the typical appearance of a cystadenoma of the pancreas. The patient's condition precluded surgery, and she was treated medically.
CASE REPORTS CASE I (L. C.): A 32-year-old white woman was admitted on July 15, 1974 for evaluation of a hard, nontender mass in the left upper quadrant, first detected by the patient two weeks earlier. She had no other medical complaints. Examination revealed a large mass in the left upper quadrant, which was believed to be an enlarged spleen. A radionuclide study of the liver and spleen was normal. Excretory urography revealed that the mass was anterior to the kidney and did not arise from it. An ultrasound study revealed a large, sonolucent septate mass displacing the left kidney posteriorly (Fig. 1). An upper gastrointestinal series showed an extrinsic pressure defect on the greater curvature of the stomach and displacement of loops of the jejunum. The barium enema study was unremarkable except for a low splenic flexure. At surgery an 8-cm cystic mass was resected along with the spleen. The final diagnosis was mucinous cystadenoma of the pancreas.
DISCUSSION
Cystadenoma of the pancreas is a relatively uncommon tumor. Only small series have been reported since 1971, when Lewis and Dormandy found a total of 251 cases in the literature (6). Most cystadenomas occur in women, primarily those 30 to 60 years of age. The great majority of patients have a palpable abdominal mass, most often in the body or tail of the pancreas although it may occur in the pancreatic head. The findings on plain films, excretory urograms, and barium studies are nonspecific, showing displacement of organs, extrinsic pressure defects in hollow visci, a softtissue mass, and sometimes calcifications. Angiography has generally been considered quite specific, showing a hypervascular mass supplied by displaced pancreatic vessels and frequently containing cystic (hypovascular) areas (1). Four cases have also been reported in which the entire lesion was relatively hypovascular and difficult to distinguish from a pancreatic pseudocyst (1, 8).
CASE II (M. R.): A 59-year-old white woman had had nausea, vomiting, diarrhea, and severe pain radiating to the back for several months prior to admission. She had lost 11 kg (25 lb.) and exhibited jaundice, dark urine, and acholic stools, though jaundice was not present at the time of admission. On physical examination, she appeared quite ill. An upper gastrointestinal series demonstrated a mass in the head of the pancreas, indenting the medial aspect of the duodenal loop, with displacement of the antrum of the stomach upward and to the left. No mucosal destruction was seen. An ultrasound study revealed a large sonolucent mass in the region of the head of the pancreas. Internal echoes were noted at lower gain and increased at higher gain; they suggested the presence of septa (Fig. 2). Angiography revealed a hypervascular mass characteristic of a
1 From the Departments of Radiology of the University of Michigan Medical Center, Ann Arbor, Mich. (A. H. W., Assistant Professor and Director of Ultrasound) and the University of Kansas Medical Center, Kansas City, Kan. (W. J. W., Assistant Professor). Accepted for publication in October 1975. sjh
203
204
ALAN
J.
WOLSON AND WILLIAM
t
a
I
! • t'
WALLS
April 1976
Fig. 1. CASE I. Sonolucent septate left-upperquadrant mass with well-defined but slightly irregular margins in both longitudinal (A) and transverse (C) sections. A longitudinal section at high gain (B) reveals increased irregularity of the margins and excellent through-transmission. CEPH = cephalad; ANT anterior; R right; CYST-AD cystadenorna. The longitudinal sections were made 3 cm to the left of the midline; the transverse section was made 6 cm below the xiphoid .
=
=
B
X-15
J.
X-15
=
.,. KG.
Fig. 2. CASE II. A-C. Echograms of the sonolucent septate right-upper-quadrant mass reveal well-defined, irregular margins (A and C). At high gain (B), there are filling in from the margins, more echoes from the septum, and good through-transmission. R = right; C, CYST-AD = cystadenoma; ANT anterior; CEPH cephalad. The transverse sections were made 15 cm below the xiphoid; the longitudinal section was made 2 cm to the right of the midline.
=
L+2
CYST-AD
=
Vol. 119
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Ultrasound
Fig. 4. CASE III. Transverse section demonstrates a sonolucent septate lesion (c). The margins are welldefined and slightly irregular, andthere is through-transmission, ant = anterior; L = left. CONCLUSION
Fig. 3. CASE II. Theangiogram revealsa hypervascular lesion with avascular areas, characteristic of a cystadenoma. We have performed ultrasound examinations on 3 patients with abdominal masses which ultimately turned out to be pancreatic cystadenomas. To our knowledge, the ultrasound appearance of this lesion has not been reported previously. All 3 patients had well-defined, sonolucent lesions, in the tail of the pancreas in 2 (CASES I and III) and in the pancreatic head in one (CASE II). All tumors had well-defined but slightly irregular margins, good through-transmission, and internal echoes from septa. As gain wasincreased, additional internal echoes appeared in all cases. Angiography was performed in only 2 patients (CASES II and III); both had typical hypervascular lesions (Fig. 3). Surgical resection confirmed the diagnosis in 2 patients (CASES I and II), but one patient was too ill for surgery and the angiogram was the sole basis for the diagnosis. The presence of a well-defined sonolucent lesion in the area of the pancreas raises several diagnostic possibilities, including pseudocyst, focal pancreatitis, occasionally carcinoma of the pancreas, and rarely a homogeneous solid mass such as lymphoma (9). The 3 cases reported here indicate that cystadenoma should be added to this list. It would be difficult to distinguish a cystadenoma from a septate pseudocyst, although the latter is uncommon: pseudocysts do tend to have less irregular borders unless infection or hemorrhage has occurred, and they generally exhibit greater throughtransmission than cystadenomas. Focal pancreatitis may demonstrate internal echoes, but they are unlikely to take the form of septa (9). Some homogeneous solid lesions may cause difficulty, particularly lymphoma, which may appear cystic and have internal structures similar to septa. While some carcinomas of the pancreas do have a sonolucent appearance, they tend to fill in with echoes at lower gain and have less through-transmission than the cystadenomas we have seen.
Ultrasound is an important noninvasive method of detecting and evaluating pancreatic masses. Our experience suggests that pancreatic cystadenomas have a characteristic ultrasonic appearance. While other lesions may look similar, a sonolucent lesion with strong through-transmission, slight irregularity of the wall, and an internal septum should suggest cystadenoma, particularly in the absence of a history of pancreatitis. ADDENDUM: Since this paper was accepted, two additional cases have been seen at UMMC. Both patients had ultrasonic findings identical to the 3 cases reported here, and their condition was diagnosed using the criteria established above. Department of Radiology Division of Ultrasound University of Michigan Medical Center Ann Arbor, Mich. 48104 REFERENCES 1. Boijsen E: Pancreatic angiography. [In] Abrams HL, ed: Angiography. Boston, Little, Brown, 2d Ed, 1971, Chapt 60, pp 967-968 2. Engelhart G, Blauenstein UW: Ultrasound in the diagnosis of malignant pancreatic tumours. Gut 11:443-449, May 1970 3. Filly RA, Freimanis AK: Echographic diagnosis of pancreatic lesions. Ultrasound scanning techniques and diagnostic findings. Radiology 96:575-582, Sep 1970 4. Holm HH: Ultrasonic scanning in the diagnosis of spaceoccupying lesions of the upperabdomen. Br J Radiol 44:24-36, Jan 1971 5. Leopold GR: Pancreatic echography: a new dimension in the diagnosis of pseudocyst. Radiology 104:365-369, Aug 1972 6. LewisA, Dormandy J: Cystadenoma of the pancreas. A report of two cases. Br J Surg 58:420-422, Jun 1971 7. Kahn PC: Pancreatic echography. [In] Eaton SB Jr, Ferrucci JT Jr, ed: Radiology of the Pancreas and Duodenum. Philadelphia, Saunders, 1973,Chapt 9, pp 276-288 8. Pressman BD, Asch T, Casarella WJ: Cystadenoma of the pancreas. A reappraisal of angiographic findings. Am J Roentgenol 119:115-120, Sep 1973 9. Sokoloff J, Gosink BB, Leopold GR, et al: Pitfalls in the echographic evaluation of pancreatic disease. J Clin Ultrasound 2: 321-326, Dec 1974 10. Stuber JL, Templeton AW, Bishop K: Sonographic diagnosis of pancreatic lesions. Am J Roentgenol 116:406-412, Oct 1972 11. Templeton AW, Stuber JL: Abdominal and retroperitoneal sonography. Am J RoentgenoI113:741-748, Dec 1971 12. Walls WJ, Gonzalez G, Martin NL, et al: B-scan ultrasound evaluation of the pancreas. Advantages and accuracy compared to otherdiagnostic techniques. Radiology 114:127-134, Jan 1975
