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Seaweed floating in the pericardium: a rare case of primary dedifferentiated liposarcoma
Cardiovascular Pathology xxx (2015) xxx–xxx
Contents lists available at ScienceDirect
Cardiovascular Pathology
Case Report
Seaweed floating in the pericardium: a rare case of primary dedifferentiated liposarcoma Gregoriana Zanini a,⁎, Elio Gorga b, Federica Pasini b, Marianna Salemme c, Giulia Petrilli c, Luisa Bercich c, Roberto Lorusso d, Gian Franco Pasini a a
Cardiology Unit, La Memoria Hospital Gavardo, Brescia, Italy Department of Medical–Surgical Specialty, Radiology and Health Care, Cardiovascular Disease Section, School of Medicine, Spedali Civili Hospital, Brescia, Italy Pathology Department, Spedali Civili Hospital, Brescia, Italy d Cardiac Surgery Unit, Spedali Civili Hospital, Brescia, Italy b c
a r t i c l e
i n f o
Article history: Received 12 August 2015 Received in revised form 1 October 2015 Accepted 6 October 2015 Available online xxxx Keywords: Liposarcoma Pericardial tumor Thoracic surgery
a b s t r a c t Primary cardiac tumors are uncommon and primary liposarcoma of the pericardium is extremely rare. We describe the case of a 55-year-old Caucasian woman without significant medical history, who presented with 3 weeks complain of dyspnea, peripheral edema, and gain weight. Echocardiography revealed a huge pericardial mass confirmed by computed tomography and by magnetic resonance. The lesion was primitive of the pericardium but the surgery was not able to cut it off because of the absence of cleavage planes. Histopathologic analysis detected a dedifferentiated liposarcoma. Mediastinum compression syndrome brought the patient to the exitus in a few days. © 2015 Elsevier Inc. All rights reserved.
1. Introduction Primary pericardium tumors are extremely rare. We describe a case of a peculiar histological type of liposarcoma, named dedifferentiated liposarcoma, which induced compression of mediastinal structures rapidly leading to patient death. 2. Case report A 55-year-old Caucasian woman was evaluated because of recent onset of dyspnea, peripheral edema, and weight gain. Breath rate was 24/min, arterial oxygen saturation was 95%, arterial blood pressure was 100/70 mmHg, and heart rate was 108 bpm. Electrocardiogram showed low QRS voltages and blood test showed a slight increase of C-reactive protein (2.3 mg/dL, normal values b 0.5) and low albumin levels (50.7%, normal values 55–65%). Echocardiography revealed marked pericardial effusion with an intrapericardial isoechogenic mass (6–7 cm×3–4 cm) presenting a seaweed-type aspect. The mass
We declare that there is no conflict of interest. Neither this manuscript nor any part of it is under consideration by another journal. Funding: We confirm that we have no organizations that funded our work. ⁎ Corresponding author. La Memoria Hospital — Via Gosa, 74 — Gavardo, Brescia, Italy. Tel./fax: +39-0365-378325. E-mail address: [email protected] (G. Zanini).
was attached to the visceral and parietal pericardium and was located at the posterolateral ventricular wall extending toward the cardiac apex (Fig. 1B). Lateral left and right ventricular walls showed a dense aspect. Biventricular function was preserved but there was a mild collapse of right atrial wall and inferior vena cava congestion. Chest X-ray showed bilateral pleural effusion, whereas abdomen ultrasound was negative. Cytohistological examination of pleural and pericardial fluids showed serum-hematic liquids with no atypical cells. Cultural examinations were negative. The patient underwent computer tomography (Fig. 1C) and magnetic resonance imaging (Fig. 1A). A lobulated mass encircling the heart in the pericardial sac (maximum 64 mm around the anterior wall) with nonhomogeneous density and enhancement was evidenced. Superior vena cava, pulmonary veins, and pulmonary artery were severely compressed. No evidence of secondary lesion was shown. A positron emission tomography confirmed the primary pericardial location. At exploratory minithoracotomy (with biopsy) (Fig. 2), no cleavage plane was identified, thereby indicating the unfeasibility of the surgical excision. The patient died 2 days later due to mediastinal compression syndrome. Besides the classical liposarcoma pattern, that is well-differentiated lipoblastic areas, histological examination showed myxoid/round and pleomorphic cells indicative of dedifferentiated liposarcoma. Several mitotic figures, also atypical, and significant necrosis were also present (Fig. 1D, a and b). Detection of MDM2 amplification by immunohistochemistry (IIC — clone 1B10; Leica Microsystems, Newcastle upon Tyne, UK) and fluorescence in situ hybridization revealed its overexpression (Fig. 1D, c and d).
http://dx.doi.org/10.1016/j.carpath.2015.10.003 1054-8807/© 2015 Elsevier Inc. All rights reserved.
Please cite this article as: Zanini G, et al, Seaweed floating in the pericardium: a rare case of primary dedifferentiated liposarcoma, Cardiovasc Pathol (2015), http://dx.doi.org/10.1016/j.carpath.2015.10.003
2
G. Zanini et al. / Cardiovascular Pathology xxx (2015) xxx–xxx
Fig. 1. (A) Magnetic resonance: pericardium almost totally replaced by mass that surrounds the heart in an almost circumferential, cystic signal with irregular septa and nodules that are impregnated. Maximum thickness of 64 mm along the anterior wall of the left ventricle. Atrial compression of the superior vena cava, pulmonary veins, and left main pulmonary artery is shown; (B) echocardiography: apical four-chamber image. Pericardial circumferential effusion with an intrapericardial isoechogenic mass (6–7 cm×3–4 cm) with a seaweed typing aspect. (C) computer tomography: abundant pericardial effusion. Diffusely thickened pericardium, multiple formations with enhancement after contrast medium. Discrete pleural effusion is evident; (D) microscopic image showing area with lipoblastic component (a), dedifferentiated area (b), and area with overexpression of MDM2 (c and d).
3. Discussion Primary mediastinal liposarcoma is extremely rare, constituting about 13% of all cardiac sarcomas and b1% of mediastinal tumors. The exclusion of an occult primary is mandatory because secondary tumors are 100–1000 times more common [1]. Mediastinal liposarcoma develops more commonly at the posterior mediastinum and usually occurs in adults, with a peak of incidence at 40–60 years of age. Men are affected twice as often as women.
Diagnosis and classification of liposarcoma is based on histopathologic criteria established by the World Health Organization (last 2013 classification): adipocytic tumors could be divided into benign, intermediate (locally aggressive), and malignant. Liposarcoma falls in the last two groups and could be classified in atypical lipomatous tumor/welldifferentiated liposarcoma (intermediate), dedifferentiated, myxoid, pleomorphic, and not otherwise specified (all malignant) [2]. Several genetic aberrations are associated with liposarcoma subtype [3] (Table 1). Dedifferentiated liposarcoma is an atypical lipomatous tumor/welldifferentiated liposarcoma showing progression, either in the primary or in a recurrence, to (usually nonlipogenic) sarcoma of variable histological grade. A well-differentiated component may not be identifiable (primarily due to insufficient sampling); rarely, the high-grade component may be lipogenic, but in most cases, there is substantial
Table 1 Genetic aberration associated with liposarcoma subtypes (modified from A. P. Dei Tos) Tumor type
Cytogenetic aberration
Molecular genetics
Atypical lipomatous tumor/ well-differentiated liposarcoma Dedifferentiated liposarcoma
Ring chromosomes and giant markers (12q13-15)
Amplification of MDM2, CDK4, HMGA2 Amplification of MDM2, CDK4, HMGA2 DDIT3/FUS DDIT3/ EWSR1 mutations TP53 in 60%, NF1 in 5%
Myxoid liposarcoma Fig. 2. Macroscopic image of the pathologic samples: multiple fragments of tissue grayish translucent, gelatinous texture, and supple, the eldest of 4.8 cm×3.3 cm.
Pleomorphic liposarcoma
Ring chromosomes and giant markers (12q13-15) t(12;16)(q13;p11) t(12;22)(q13;q22) Complex karyotypic aberrations
Please cite this article as: Zanini G, et al, Seaweed floating in the pericardium: a rare case of primary dedifferentiated liposarcoma, Cardiovasc Pathol (2015), http://dx.doi.org/10.1016/j.carpath.2015.10.003
G. Zanini et al. / Cardiovascular Pathology xxx (2015) xxx–xxx
amplification of MDM2 gene. Dedifferentiated areas exhibit a variable histological pattern, but most frequently, they resemble undifferentiated pleomorphic sarcoma or intermediate to high-grade myxofibrosarcoma. Occasionally, as in our case, the high-grade component may exhibit overt lipoblastic differentiation, in some cases as sheets of atypical pleomorphic adipocytic cells resulting in areas morphologically indistinguishable from pleomorphic liposarcoma (“homologous lipoblastic differentiation”) [2]. Depending on their size and location, primary pericardial liposarcoma may present with chest pain [4,5], symptoms of right- or left-sided heart failure [5,6], pericarditis with or without cardiac tamponade [7], sudden cardiac death [8], palpitation, rhythm disturbances, syncope, angina, cough, and constitutional symptoms like fever and weight loss. Cases where the tumor does not interfere with cardiac function may be entirely asymptomatic. The primary diagnostic tool is the histopathologic finding, but as dedifferentiated liposarcoma of pericardium is extremely rare, it can easily be misdiagnosed because of the great variety of histological presentation. Thus, adequate samples, high-quality paraffin-embedded slides stained with hematoxylin and eosin, and careful observation are essential [5]. Also molecular assays are crucial for a correct diagnosis. Echocardiography, computed tomography, and magnetic resonance imaging help the clinician in the differential diagnosis [9]. In general, the treatment of choice is surgery, and complete resection is recommended whenever possible [6]. Prognosis depends on the histological subtype and on feasibility of surgical resection including wide margins of safety. Recurrence is seen in approximately 40% of the cases and has been reported at up to 14 years after the initial surgical procedure [6]. Complete tumor resection and adjuvant radiation therapy contribute to reduce the risk of local recurrence and metastasis. Features associated with longer survival include left-sided tumor, complete resection, postoperative adjuvant therapy, and tumors with less than 10 mitoses/HPF and absent necrosis [6].
3
4. Conclusion Our case report matches some typical findings related to pericardial liposarcoma: relative young age, typical symptoms, and the necessity of histopathologic analysis to reach a correct diagnosis. Radiological examinations are usually insufficient to determine the diagnosis. Echocardiography assumes an important role in the initial evaluation. Surgical resection is the treatment of choice. In our case, the severe infiltration of the nearest cardiovascular structures hampered surgical excision, with dismal prognosis due to rapidly progressive mediastinal compression. Dedifferentiated liposarcoma is the rarest subtype of liposarcoma, and the pericardial location is even more rare. To the best of our knowledge, no more than 12 cases are reported in PubMed database since 1973. Our case proves the importance of histopathologic and molecular analysis to achieve the right diagnosis. We underline also the rapidly unfavorable prognosis if surgical excision is not feasible. References [1] Sarjeant JM, Butany J, Cusimano RJ. Cancer of the heart: epidemiology and management of primary tumors and metastasis. Am J Cardiovasc Drugs 2003;3:407–21. [2] Fletcher C DM, Bridge JA, Hogendoorn P, Mertens F. WHO classification of tumours of soft tissue and bone. WHO Classification of Tumours, 5. IARC WHO Classification of Tumours, No. 5, 4th edit; 2013. [3] Dei Tos AP. Liposarcomas: diagnostic pitfalls and new insights. Histopathology 2014; 64:38–52. [4] Lacey CJ, Petch MC. Primary liposarcoma of the pericardium. Thorax 1979;34:120–2. [5] Wang JG, Wei ZM, Liu H, Li YJ. Primary pleomorphic liposarcoma of pericardium. Interact Cardiovasc Thorac Surg 2010;11:325–7. [6] Steger C. Primary liposarcoma of the heart. BMJ Case Rep 2011. http://dx.doi.org/10. 1136/bcr.03.2011.4013. [7] Lococo F, Cesario A, Meacci E, Vita LM, Porziella V, Margaritora S, et al. Huge primary pericardial liposarcoma. Thorac Cardiovasc Surg 2011;59:172–3. [8] Papavdi A, Agapitos E. Undiagnosed primary cardiac liposarcoma in an adult: a case report and review of the literature. Am J Forensic Med Pathol 2013;34:299–301. [9] Kim EY, Park KY, Jeon YB, Ha SY, Chung WJ. A primary pericardial liposarcoma mimicking intracardiac neoplasm on echocardiography: role of computed tomography and magnetic resonance imaging in the differential diagnosis. Int J Cardiol 2013; 167:e92–4.
Please cite this article as: Zanini G, et al, Seaweed floating in the pericardium: a rare case of primary dedifferentiated liposarcoma, Cardiovasc Pathol (2015), http://dx.doi.org/10.1016/j.carpath.2015.10.003
Contents lists available at ScienceDirect
Cardiovascular Pathology
Case Report
Seaweed floating in the pericardium: a rare case of primary dedifferentiated liposarcoma Gregoriana Zanini a,⁎, Elio Gorga b, Federica Pasini b, Marianna Salemme c, Giulia Petrilli c, Luisa Bercich c, Roberto Lorusso d, Gian Franco Pasini a a
Cardiology Unit, La Memoria Hospital Gavardo, Brescia, Italy Department of Medical–Surgical Specialty, Radiology and Health Care, Cardiovascular Disease Section, School of Medicine, Spedali Civili Hospital, Brescia, Italy Pathology Department, Spedali Civili Hospital, Brescia, Italy d Cardiac Surgery Unit, Spedali Civili Hospital, Brescia, Italy b c
a r t i c l e
i n f o
Article history: Received 12 August 2015 Received in revised form 1 October 2015 Accepted 6 October 2015 Available online xxxx Keywords: Liposarcoma Pericardial tumor Thoracic surgery
a b s t r a c t Primary cardiac tumors are uncommon and primary liposarcoma of the pericardium is extremely rare. We describe the case of a 55-year-old Caucasian woman without significant medical history, who presented with 3 weeks complain of dyspnea, peripheral edema, and gain weight. Echocardiography revealed a huge pericardial mass confirmed by computed tomography and by magnetic resonance. The lesion was primitive of the pericardium but the surgery was not able to cut it off because of the absence of cleavage planes. Histopathologic analysis detected a dedifferentiated liposarcoma. Mediastinum compression syndrome brought the patient to the exitus in a few days. © 2015 Elsevier Inc. All rights reserved.
1. Introduction Primary pericardium tumors are extremely rare. We describe a case of a peculiar histological type of liposarcoma, named dedifferentiated liposarcoma, which induced compression of mediastinal structures rapidly leading to patient death. 2. Case report A 55-year-old Caucasian woman was evaluated because of recent onset of dyspnea, peripheral edema, and weight gain. Breath rate was 24/min, arterial oxygen saturation was 95%, arterial blood pressure was 100/70 mmHg, and heart rate was 108 bpm. Electrocardiogram showed low QRS voltages and blood test showed a slight increase of C-reactive protein (2.3 mg/dL, normal values b 0.5) and low albumin levels (50.7%, normal values 55–65%). Echocardiography revealed marked pericardial effusion with an intrapericardial isoechogenic mass (6–7 cm×3–4 cm) presenting a seaweed-type aspect. The mass
We declare that there is no conflict of interest. Neither this manuscript nor any part of it is under consideration by another journal. Funding: We confirm that we have no organizations that funded our work. ⁎ Corresponding author. La Memoria Hospital — Via Gosa, 74 — Gavardo, Brescia, Italy. Tel./fax: +39-0365-378325. E-mail address: [email protected] (G. Zanini).
was attached to the visceral and parietal pericardium and was located at the posterolateral ventricular wall extending toward the cardiac apex (Fig. 1B). Lateral left and right ventricular walls showed a dense aspect. Biventricular function was preserved but there was a mild collapse of right atrial wall and inferior vena cava congestion. Chest X-ray showed bilateral pleural effusion, whereas abdomen ultrasound was negative. Cytohistological examination of pleural and pericardial fluids showed serum-hematic liquids with no atypical cells. Cultural examinations were negative. The patient underwent computer tomography (Fig. 1C) and magnetic resonance imaging (Fig. 1A). A lobulated mass encircling the heart in the pericardial sac (maximum 64 mm around the anterior wall) with nonhomogeneous density and enhancement was evidenced. Superior vena cava, pulmonary veins, and pulmonary artery were severely compressed. No evidence of secondary lesion was shown. A positron emission tomography confirmed the primary pericardial location. At exploratory minithoracotomy (with biopsy) (Fig. 2), no cleavage plane was identified, thereby indicating the unfeasibility of the surgical excision. The patient died 2 days later due to mediastinal compression syndrome. Besides the classical liposarcoma pattern, that is well-differentiated lipoblastic areas, histological examination showed myxoid/round and pleomorphic cells indicative of dedifferentiated liposarcoma. Several mitotic figures, also atypical, and significant necrosis were also present (Fig. 1D, a and b). Detection of MDM2 amplification by immunohistochemistry (IIC — clone 1B10; Leica Microsystems, Newcastle upon Tyne, UK) and fluorescence in situ hybridization revealed its overexpression (Fig. 1D, c and d).
http://dx.doi.org/10.1016/j.carpath.2015.10.003 1054-8807/© 2015 Elsevier Inc. All rights reserved.
Please cite this article as: Zanini G, et al, Seaweed floating in the pericardium: a rare case of primary dedifferentiated liposarcoma, Cardiovasc Pathol (2015), http://dx.doi.org/10.1016/j.carpath.2015.10.003
2
G. Zanini et al. / Cardiovascular Pathology xxx (2015) xxx–xxx
Fig. 1. (A) Magnetic resonance: pericardium almost totally replaced by mass that surrounds the heart in an almost circumferential, cystic signal with irregular septa and nodules that are impregnated. Maximum thickness of 64 mm along the anterior wall of the left ventricle. Atrial compression of the superior vena cava, pulmonary veins, and left main pulmonary artery is shown; (B) echocardiography: apical four-chamber image. Pericardial circumferential effusion with an intrapericardial isoechogenic mass (6–7 cm×3–4 cm) with a seaweed typing aspect. (C) computer tomography: abundant pericardial effusion. Diffusely thickened pericardium, multiple formations with enhancement after contrast medium. Discrete pleural effusion is evident; (D) microscopic image showing area with lipoblastic component (a), dedifferentiated area (b), and area with overexpression of MDM2 (c and d).
3. Discussion Primary mediastinal liposarcoma is extremely rare, constituting about 13% of all cardiac sarcomas and b1% of mediastinal tumors. The exclusion of an occult primary is mandatory because secondary tumors are 100–1000 times more common [1]. Mediastinal liposarcoma develops more commonly at the posterior mediastinum and usually occurs in adults, with a peak of incidence at 40–60 years of age. Men are affected twice as often as women.
Diagnosis and classification of liposarcoma is based on histopathologic criteria established by the World Health Organization (last 2013 classification): adipocytic tumors could be divided into benign, intermediate (locally aggressive), and malignant. Liposarcoma falls in the last two groups and could be classified in atypical lipomatous tumor/welldifferentiated liposarcoma (intermediate), dedifferentiated, myxoid, pleomorphic, and not otherwise specified (all malignant) [2]. Several genetic aberrations are associated with liposarcoma subtype [3] (Table 1). Dedifferentiated liposarcoma is an atypical lipomatous tumor/welldifferentiated liposarcoma showing progression, either in the primary or in a recurrence, to (usually nonlipogenic) sarcoma of variable histological grade. A well-differentiated component may not be identifiable (primarily due to insufficient sampling); rarely, the high-grade component may be lipogenic, but in most cases, there is substantial
Table 1 Genetic aberration associated with liposarcoma subtypes (modified from A. P. Dei Tos) Tumor type
Cytogenetic aberration
Molecular genetics
Atypical lipomatous tumor/ well-differentiated liposarcoma Dedifferentiated liposarcoma
Ring chromosomes and giant markers (12q13-15)
Amplification of MDM2, CDK4, HMGA2 Amplification of MDM2, CDK4, HMGA2 DDIT3/FUS DDIT3/ EWSR1 mutations TP53 in 60%, NF1 in 5%
Myxoid liposarcoma Fig. 2. Macroscopic image of the pathologic samples: multiple fragments of tissue grayish translucent, gelatinous texture, and supple, the eldest of 4.8 cm×3.3 cm.
Pleomorphic liposarcoma
Ring chromosomes and giant markers (12q13-15) t(12;16)(q13;p11) t(12;22)(q13;q22) Complex karyotypic aberrations
Please cite this article as: Zanini G, et al, Seaweed floating in the pericardium: a rare case of primary dedifferentiated liposarcoma, Cardiovasc Pathol (2015), http://dx.doi.org/10.1016/j.carpath.2015.10.003
G. Zanini et al. / Cardiovascular Pathology xxx (2015) xxx–xxx
amplification of MDM2 gene. Dedifferentiated areas exhibit a variable histological pattern, but most frequently, they resemble undifferentiated pleomorphic sarcoma or intermediate to high-grade myxofibrosarcoma. Occasionally, as in our case, the high-grade component may exhibit overt lipoblastic differentiation, in some cases as sheets of atypical pleomorphic adipocytic cells resulting in areas morphologically indistinguishable from pleomorphic liposarcoma (“homologous lipoblastic differentiation”) [2]. Depending on their size and location, primary pericardial liposarcoma may present with chest pain [4,5], symptoms of right- or left-sided heart failure [5,6], pericarditis with or without cardiac tamponade [7], sudden cardiac death [8], palpitation, rhythm disturbances, syncope, angina, cough, and constitutional symptoms like fever and weight loss. Cases where the tumor does not interfere with cardiac function may be entirely asymptomatic. The primary diagnostic tool is the histopathologic finding, but as dedifferentiated liposarcoma of pericardium is extremely rare, it can easily be misdiagnosed because of the great variety of histological presentation. Thus, adequate samples, high-quality paraffin-embedded slides stained with hematoxylin and eosin, and careful observation are essential [5]. Also molecular assays are crucial for a correct diagnosis. Echocardiography, computed tomography, and magnetic resonance imaging help the clinician in the differential diagnosis [9]. In general, the treatment of choice is surgery, and complete resection is recommended whenever possible [6]. Prognosis depends on the histological subtype and on feasibility of surgical resection including wide margins of safety. Recurrence is seen in approximately 40% of the cases and has been reported at up to 14 years after the initial surgical procedure [6]. Complete tumor resection and adjuvant radiation therapy contribute to reduce the risk of local recurrence and metastasis. Features associated with longer survival include left-sided tumor, complete resection, postoperative adjuvant therapy, and tumors with less than 10 mitoses/HPF and absent necrosis [6].
3
4. Conclusion Our case report matches some typical findings related to pericardial liposarcoma: relative young age, typical symptoms, and the necessity of histopathologic analysis to reach a correct diagnosis. Radiological examinations are usually insufficient to determine the diagnosis. Echocardiography assumes an important role in the initial evaluation. Surgical resection is the treatment of choice. In our case, the severe infiltration of the nearest cardiovascular structures hampered surgical excision, with dismal prognosis due to rapidly progressive mediastinal compression. Dedifferentiated liposarcoma is the rarest subtype of liposarcoma, and the pericardial location is even more rare. To the best of our knowledge, no more than 12 cases are reported in PubMed database since 1973. Our case proves the importance of histopathologic and molecular analysis to achieve the right diagnosis. We underline also the rapidly unfavorable prognosis if surgical excision is not feasible. References [1] Sarjeant JM, Butany J, Cusimano RJ. Cancer of the heart: epidemiology and management of primary tumors and metastasis. Am J Cardiovasc Drugs 2003;3:407–21. [2] Fletcher C DM, Bridge JA, Hogendoorn P, Mertens F. WHO classification of tumours of soft tissue and bone. WHO Classification of Tumours, 5. IARC WHO Classification of Tumours, No. 5, 4th edit; 2013. [3] Dei Tos AP. Liposarcomas: diagnostic pitfalls and new insights. Histopathology 2014; 64:38–52. [4] Lacey CJ, Petch MC. Primary liposarcoma of the pericardium. Thorax 1979;34:120–2. [5] Wang JG, Wei ZM, Liu H, Li YJ. Primary pleomorphic liposarcoma of pericardium. Interact Cardiovasc Thorac Surg 2010;11:325–7. [6] Steger C. Primary liposarcoma of the heart. BMJ Case Rep 2011. http://dx.doi.org/10. 1136/bcr.03.2011.4013. [7] Lococo F, Cesario A, Meacci E, Vita LM, Porziella V, Margaritora S, et al. Huge primary pericardial liposarcoma. Thorac Cardiovasc Surg 2011;59:172–3. [8] Papavdi A, Agapitos E. Undiagnosed primary cardiac liposarcoma in an adult: a case report and review of the literature. Am J Forensic Med Pathol 2013;34:299–301. [9] Kim EY, Park KY, Jeon YB, Ha SY, Chung WJ. A primary pericardial liposarcoma mimicking intracardiac neoplasm on echocardiography: role of computed tomography and magnetic resonance imaging in the differential diagnosis. Int J Cardiol 2013; 167:e92–4.
Please cite this article as: Zanini G, et al, Seaweed floating in the pericardium: a rare case of primary dedifferentiated liposarcoma, Cardiovasc Pathol (2015), http://dx.doi.org/10.1016/j.carpath.2015.10.003