Novel Insights from Clinical Practice Pediatr Neurosurg 2014–15;50:73–75 DOI: 10.1159/000377731
Received: December 5, 2014 Accepted after revision: February 1, 2015 Published online: March 26, 2015
Malignant Cause of Ventriculoperitoneal Shunt ‘Pseudocyst’: A Case Report Jonathan Awori a Chris Y. Wu a Cormac O. Maher b a
University of Michigan Medical School, and b Department of Neurosurgery, University of Michigan, Ann Arbor, Mich., USA
Established Facts • Ventriculoperitoneal shunts can be complicated by the development of abdominal pseudocysts. • Such pseudocysts are typically treated by shunt externalization and, if infected, antibiotics.
Novel Insights • This is a very rare case of abdominal malignancy mimicking an abdominal pseudocyst.
Abstract Abdominal pseudocysts are an uncommon complication of ventriculoperitoneal (VP) shunts. We present the case of a 4-year-old boy with a history of complicated hydrocephalus managed with a VP shunt due to sequelae of prematurity. The patient presented with abdominal distention, and a pseudocyst was diagnosed. Despite shunt externalization and aspiration, the pseudocyst continued to produce up to 1 liter of serosanguineous fluid per day. After MRI revealed malignant features within the pseudocyst, laparotomy was performed and the pseudocyst was partially excised. Pathology reports suggested sarcoma. The cystic mass grew back aggressively, accompanied by distant metastasis. The patient’s condition deteriorated and he died from his disease. To our knowledge, this represents the first report of an abdominal malignancy mimicking a pseudocyst and causing VP shunt failure.
Introduction
Cerebrospinal fluid-filled abdominal pseudocysts are an uncommon complication of ventriculoperitoneal (VP) shunts. We present the unique case of a 4-year-old male patient with hydrocephalus and an abdominal mass. The mass was initially thought to be a simple pseudocyst, but was found to demonstrate malignant changes. Pathology subsequently revealed the mass to be consistent with undifferentiated sarcoma. To our knowledge, this is the first report of such a case in the literature.
Case Report The patient was a 4-year-old African-American boy born at 23 weeks’ gestation, with a significant past medical history due to premature birth. Relevant complications of prematurity included severe intraventricular hemorrhage leading to multiloculated hydrocephalus for which the patient had multiple VP shunts placed and revised, necrotizing enterocolitis necessitating laparotomy with small bowel resection, epilepsy, cerebral palsy, feeding tube depen-
© 2015 S. Karger AG, Basel © 2015 S. Karger AG, Basel 1016–2291/15/0502–0073$39.50/0 E-Mail [email protected] www.karger.com/pne
Cormac O. Maher, MD Department of Neurosurgery, University of Michigan 1500 East Medical Center Drive, Room 3552 TC Ann Arbor, MI 48109-5338 (USA) E-Mail cmaher @ med.umich.edu
Downloaded by: Univ. of California San Diego 132.239.1.230 - 6/11/2015 3:02:30 AM
Key Words Abdominal pseudocyst · Cancer · Malignancy · Ventriculoperitoneal shunt
a
Fig. 2. Abdominopelvic T2-weighted coronal MRI with fat saturation demonstrating the multiloculated pseudocyst in the right lower mid-abdomen and upper pelvis. Dense peripheral frond-like and nodular enhancement throughout the mass suggested possible malignancy.
Fig. 1. a Abdominal ultrasound with coronal view of the large,
complex, septated pseudocyst extending from the right subhepatic region to the suprapubic area. b Right abdominal sagittal view showing the pseudocyst measuring 10.92 × 11.69 cm.
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Pediatr Neurosurg 2014–15;50:73–75 DOI: 10.1159/000377731
Awori/Wu/Maher
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b
dence, and multiple hospitalizations for pneumonia, and urinary tract infections. At baseline, the patient was severely developmentally delayed. Shortly after his latest shunt revision at 17 months of age, the patient had a pseudocyst around his shunt catheter tip diagnosed incidentally during a gastrointestinal assessment as the patient returned to oral feeding. The patient did not demonstrate abdominal distention, poor feeding, vomiting, or any other deviations from baseline. Cerebrospinal fluid from the shunt did not show any evidence of infection and the pseudocyst was considered a possible result of his multiple abdominal comorbidities and prior laparotomies resulting in decreased abdominal capacity to resorb fluid. Other distal sites including pulmonary and atrial had failed in the past due to very poor lung function at baseline and a prothrombotic state that had resulted in extensive venous thrombosis at other catheter sites. For these reasons, the shunt was left in place and this pseudocyst was followed over the course of the next 2 years. Ultrasound imaging during this observation period showed that the pseudocyst was fairly stable in size and character (varying from 14 × 12 × 12 to 11 × 12 × 13 cm) and the shunt was draining his ventricular system effectively despite the pseudocyst (fig. 1a, b). The patient then presented to the emergency department with increased abdominal distention and gastric tube feeding intolerance 2 years following the initial pseudocyst diagnosis. His mother
Discussion
Abdominal pseudocysts are thin-walled cystic masses filled with cerebrospinal fluid that develop around a VP shunt tip. The wall is composed of fibrous tissue without an epithelial lining [1]. The etiology of cyst formation is
References
Malignant ‘Pseudocyst’
unclear. Some authors have proposed infection as a causative factor, but evidence of infection is not found in every case [2]. Pseudocyst formation complicates between 0.1 and 10% of VP shunts [3–5]. The two most significant risk factors for pseudocyst formation are multiple shunt revisions and infection [6]. In their analysis of a series of 14 patients, Rainov et al. [6] found that the most frequent presenting symptoms of abdominal pseudocyst were abdominal pain and distention. Other less common presenting symptoms include signs of shunt failure such as headache or vomiting. Ultrasound findings include a sonolucent mass with either uniform echotexture or septa, internal echoes, and fluid levels [7]. Shunt-associated pseudocysts typically resorb following removal of the shunt and treatment of any associated infection [2, 6]. Our patient reflected the most common presenting symptoms of abdominal pain and distention, and had the risk factors of multiple shunt revisions, history of necrotizing enterocolitis, and prior exploratory laparotomy with small bowel resection. The clinical picture became highly unusual when our patient continued to produce 1 liter of fluid per day from a drain in the pseudocyst. It was this unexplained and persistent production of fluid that prompted further imaging and its ultimate diagnosis as an undifferentiated sarcoma. Earlier use of MRI may be helpful in arriving at a more timely and accurate identification of this mass.
1 Tamura A, Shida D, Tsutsumi K: Abdominal cerebrospinal fluid pseudocyst occurring 21 years after ventriculoperitoneal shunt placement: a case report. BMC Surg 2013;13:1471– 2482. 2 Mobley LW 3rd, Doran SE, Hellbusch LC: Abdominal pseudocyst: predisposing factors and treatment algorithm. Pediatr Neurosurg 2005;41:77–83. 3 de Oliveira RS, Barbosa A, Vicente YA, Machado HR: An alternative approach for management of abdominal cerebrospinal fluid pseudocysts in children. Childs Nerv Syst 2007;23:85–90.
4 Ersahin Y, Mutluer S, Tekeli G: Abdominal cerebrospinal fluid pseudocysts. Childs Nerv Syst 1996;12:755–758. 5 Gaskill SJ, Marlin AE: Pseudocysts of the abdomen associated with ventriculoperitoneal shunts: a report of twelve cases and a review of the literature. Pediatr Neurosci 1989; 15: 23–26. 6 Rainov N, Schobess A, Heidecke V, Burkert W: Abdominal CSF pseudocysts in patients with ventriculo-peritoneal shunts. Report of fourteen cases and review of the literature. Acta Neurochir (Wien) 1994;127:73–78. 7 Pathi R, Sage M, Slavotinek J, Hanieh A: Abdominal cerebrospinal fluid pseudocyst. Australas Radiol 2004;48:61–63.
Pediatr Neurosurg 2014–15;50:73–75 DOI: 10.1159/000377731
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had noticed a waxing and waning of his abdominal girth for several weeks, followed by a sustained period of rapid growth in the week leading up to his admission. The patient had decreased urinary output, but did not have any neurological symptoms. The neurosurgery service admitted him for observation and noted the increased size of his pseudocyst. Drainage was arranged by the interventional radiology service. It was also determined that the shunt should be repositioned to the atrium. After aspiration and placement of a Jackson-Pratt drain, the drain continued to produce up to 1 liter of serosanguineous fluid each day. Over the course of the next 2 weeks, MRI demonstrated that the pseudocyst had multiple septations and thick walls, thought to be the result of either inflammation or an infective or malignant process (fig. 2). Cytology studies, however, were negative for malignant cells at this time. The patient then underwent an exploratory laparotomy and an extensive but subtotal removal of the presumed pseudocyst was carried out. On histological evaluation the tissue was consistent with a high-grade undifferentiated sarcoma. One month later, abdominal CT showed aggressive regrowth of the excised mass. In addition, there were new, enlarging distant lymph nodes consistent with metastatic disease. The patient was discharged to home hospice at the request of the parents.
Received: December 5, 2014 Accepted after revision: February 1, 2015 Published online: March 26, 2015
Malignant Cause of Ventriculoperitoneal Shunt ‘Pseudocyst’: A Case Report Jonathan Awori a Chris Y. Wu a Cormac O. Maher b a
University of Michigan Medical School, and b Department of Neurosurgery, University of Michigan, Ann Arbor, Mich., USA
Established Facts • Ventriculoperitoneal shunts can be complicated by the development of abdominal pseudocysts. • Such pseudocysts are typically treated by shunt externalization and, if infected, antibiotics.
Novel Insights • This is a very rare case of abdominal malignancy mimicking an abdominal pseudocyst.
Abstract Abdominal pseudocysts are an uncommon complication of ventriculoperitoneal (VP) shunts. We present the case of a 4-year-old boy with a history of complicated hydrocephalus managed with a VP shunt due to sequelae of prematurity. The patient presented with abdominal distention, and a pseudocyst was diagnosed. Despite shunt externalization and aspiration, the pseudocyst continued to produce up to 1 liter of serosanguineous fluid per day. After MRI revealed malignant features within the pseudocyst, laparotomy was performed and the pseudocyst was partially excised. Pathology reports suggested sarcoma. The cystic mass grew back aggressively, accompanied by distant metastasis. The patient’s condition deteriorated and he died from his disease. To our knowledge, this represents the first report of an abdominal malignancy mimicking a pseudocyst and causing VP shunt failure.
Introduction
Cerebrospinal fluid-filled abdominal pseudocysts are an uncommon complication of ventriculoperitoneal (VP) shunts. We present the unique case of a 4-year-old male patient with hydrocephalus and an abdominal mass. The mass was initially thought to be a simple pseudocyst, but was found to demonstrate malignant changes. Pathology subsequently revealed the mass to be consistent with undifferentiated sarcoma. To our knowledge, this is the first report of such a case in the literature.
Case Report The patient was a 4-year-old African-American boy born at 23 weeks’ gestation, with a significant past medical history due to premature birth. Relevant complications of prematurity included severe intraventricular hemorrhage leading to multiloculated hydrocephalus for which the patient had multiple VP shunts placed and revised, necrotizing enterocolitis necessitating laparotomy with small bowel resection, epilepsy, cerebral palsy, feeding tube depen-
© 2015 S. Karger AG, Basel © 2015 S. Karger AG, Basel 1016–2291/15/0502–0073$39.50/0 E-Mail [email protected] www.karger.com/pne
Cormac O. Maher, MD Department of Neurosurgery, University of Michigan 1500 East Medical Center Drive, Room 3552 TC Ann Arbor, MI 48109-5338 (USA) E-Mail cmaher @ med.umich.edu
Downloaded by: Univ. of California San Diego 132.239.1.230 - 6/11/2015 3:02:30 AM
Key Words Abdominal pseudocyst · Cancer · Malignancy · Ventriculoperitoneal shunt
a
Fig. 2. Abdominopelvic T2-weighted coronal MRI with fat saturation demonstrating the multiloculated pseudocyst in the right lower mid-abdomen and upper pelvis. Dense peripheral frond-like and nodular enhancement throughout the mass suggested possible malignancy.
Fig. 1. a Abdominal ultrasound with coronal view of the large,
complex, septated pseudocyst extending from the right subhepatic region to the suprapubic area. b Right abdominal sagittal view showing the pseudocyst measuring 10.92 × 11.69 cm.
74
Pediatr Neurosurg 2014–15;50:73–75 DOI: 10.1159/000377731
Awori/Wu/Maher
Downloaded by: Univ. of California San Diego 132.239.1.230 - 6/11/2015 3:02:30 AM
b
dence, and multiple hospitalizations for pneumonia, and urinary tract infections. At baseline, the patient was severely developmentally delayed. Shortly after his latest shunt revision at 17 months of age, the patient had a pseudocyst around his shunt catheter tip diagnosed incidentally during a gastrointestinal assessment as the patient returned to oral feeding. The patient did not demonstrate abdominal distention, poor feeding, vomiting, or any other deviations from baseline. Cerebrospinal fluid from the shunt did not show any evidence of infection and the pseudocyst was considered a possible result of his multiple abdominal comorbidities and prior laparotomies resulting in decreased abdominal capacity to resorb fluid. Other distal sites including pulmonary and atrial had failed in the past due to very poor lung function at baseline and a prothrombotic state that had resulted in extensive venous thrombosis at other catheter sites. For these reasons, the shunt was left in place and this pseudocyst was followed over the course of the next 2 years. Ultrasound imaging during this observation period showed that the pseudocyst was fairly stable in size and character (varying from 14 × 12 × 12 to 11 × 12 × 13 cm) and the shunt was draining his ventricular system effectively despite the pseudocyst (fig. 1a, b). The patient then presented to the emergency department with increased abdominal distention and gastric tube feeding intolerance 2 years following the initial pseudocyst diagnosis. His mother
Discussion
Abdominal pseudocysts are thin-walled cystic masses filled with cerebrospinal fluid that develop around a VP shunt tip. The wall is composed of fibrous tissue without an epithelial lining [1]. The etiology of cyst formation is
References
Malignant ‘Pseudocyst’
unclear. Some authors have proposed infection as a causative factor, but evidence of infection is not found in every case [2]. Pseudocyst formation complicates between 0.1 and 10% of VP shunts [3–5]. The two most significant risk factors for pseudocyst formation are multiple shunt revisions and infection [6]. In their analysis of a series of 14 patients, Rainov et al. [6] found that the most frequent presenting symptoms of abdominal pseudocyst were abdominal pain and distention. Other less common presenting symptoms include signs of shunt failure such as headache or vomiting. Ultrasound findings include a sonolucent mass with either uniform echotexture or septa, internal echoes, and fluid levels [7]. Shunt-associated pseudocysts typically resorb following removal of the shunt and treatment of any associated infection [2, 6]. Our patient reflected the most common presenting symptoms of abdominal pain and distention, and had the risk factors of multiple shunt revisions, history of necrotizing enterocolitis, and prior exploratory laparotomy with small bowel resection. The clinical picture became highly unusual when our patient continued to produce 1 liter of fluid per day from a drain in the pseudocyst. It was this unexplained and persistent production of fluid that prompted further imaging and its ultimate diagnosis as an undifferentiated sarcoma. Earlier use of MRI may be helpful in arriving at a more timely and accurate identification of this mass.
1 Tamura A, Shida D, Tsutsumi K: Abdominal cerebrospinal fluid pseudocyst occurring 21 years after ventriculoperitoneal shunt placement: a case report. BMC Surg 2013;13:1471– 2482. 2 Mobley LW 3rd, Doran SE, Hellbusch LC: Abdominal pseudocyst: predisposing factors and treatment algorithm. Pediatr Neurosurg 2005;41:77–83. 3 de Oliveira RS, Barbosa A, Vicente YA, Machado HR: An alternative approach for management of abdominal cerebrospinal fluid pseudocysts in children. Childs Nerv Syst 2007;23:85–90.
4 Ersahin Y, Mutluer S, Tekeli G: Abdominal cerebrospinal fluid pseudocysts. Childs Nerv Syst 1996;12:755–758. 5 Gaskill SJ, Marlin AE: Pseudocysts of the abdomen associated with ventriculoperitoneal shunts: a report of twelve cases and a review of the literature. Pediatr Neurosci 1989; 15: 23–26. 6 Rainov N, Schobess A, Heidecke V, Burkert W: Abdominal CSF pseudocysts in patients with ventriculo-peritoneal shunts. Report of fourteen cases and review of the literature. Acta Neurochir (Wien) 1994;127:73–78. 7 Pathi R, Sage M, Slavotinek J, Hanieh A: Abdominal cerebrospinal fluid pseudocyst. Australas Radiol 2004;48:61–63.
Pediatr Neurosurg 2014–15;50:73–75 DOI: 10.1159/000377731
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had noticed a waxing and waning of his abdominal girth for several weeks, followed by a sustained period of rapid growth in the week leading up to his admission. The patient had decreased urinary output, but did not have any neurological symptoms. The neurosurgery service admitted him for observation and noted the increased size of his pseudocyst. Drainage was arranged by the interventional radiology service. It was also determined that the shunt should be repositioned to the atrium. After aspiration and placement of a Jackson-Pratt drain, the drain continued to produce up to 1 liter of serosanguineous fluid each day. Over the course of the next 2 weeks, MRI demonstrated that the pseudocyst had multiple septations and thick walls, thought to be the result of either inflammation or an infective or malignant process (fig. 2). Cytology studies, however, were negative for malignant cells at this time. The patient then underwent an exploratory laparotomy and an extensive but subtotal removal of the presumed pseudocyst was carried out. On histological evaluation the tissue was consistent with a high-grade undifferentiated sarcoma. One month later, abdominal CT showed aggressive regrowth of the excised mass. In addition, there were new, enlarging distant lymph nodes consistent with metastatic disease. The patient was discharged to home hospice at the request of the parents.
