Pediatric and Developmental Pathology 18, 422–425, 2015 DOI: 10.2350/14-12-1592-CR.1 ª 2015 Society for Pediatric Pathology
Coexistent Chorangioma and Hepatic Adenoma in One Twin Placenta: A Case Report and Review of the Literature THOMAS S. DENAPOLI* Department of Pathology, Children’s Hospital of San Antonio, San Antonio, TX, USA
Received December 30, 2014; accepted July 14, 2015; published online July 17, 2015.
ABSTRACT Primary nontrophoblastic tumors of a placenta are very uncommon, with the majority being of vascular origin, such as chorangiomas and chorangiomatosis. Rare examples of tumor-like collections of liver tissue, morphologically consistent with hepatocellular adenomas, have been reported. We report the co-occurrence of a chorangioma and hepatic adenoma as a grossly single lesion on the fetal surface of a diamniotic dichorionic twin placenta. Key words: chorangioma, coexistent tumors, hepatic adenoma, placenta
CASE REPORT Two discrete placental discs, each with a trivessel cord and connected by thin glistening membranes, were received in formalin following the uncomplicated vaginal delivery of infant males from a 32-year-old G3P2 African-American mother following a 35-week gestation. The pregnancy had been complicated by gestational hypertension. Twin A weighed 2180 g (26–50th percentile) and had APGAR scores of 8 and 9 at 1 and 5 minutes, respectively. Twin B weighed 2220 g (26–50th percentile) and had APGAR scores of 7 and 9 at 1 and 5 minutes, respectively. The discrete single-disc placenta A weighed 308 g and was grossly unremarkable. Singledisc placenta B weighed 301 g. The combined placental weight was 609 g, lying between the 10th and 25th percentiles for twin placentas for a 35-week gestation [1]. Sectioning of placenta B revealed a 4.5 3 3.5 3 3.5-cm sharply demarcated solid nodule of tan-pink rubbery tissue subjacent to the chorioamnion of the chorionic plate (Fig. 1). Located centrally within this nodule was an ill-defined area of glistening gray-white tissue measuring 1.5 cm in greatest dimension. Histologic evaluation of the larger sharply demarcated nodule showed classic findings of a chorangioma *Corresponding author, e-mail: [email protected]
consisting of a proliferation of small vessels containing erythrocytes separated by bland fibroblastic-like stroma (Fig. 2A). Scattered throughout the nodule were larger vessels with thick walls. In contrast, the central poorly defined gray-white area noted macroscopically consisted of an unencapsulated lobular proliferation of eosinophilic polygonal epithelioid cells arranged in vague columns and nests, separated by blood-filled channels (Fig. 2B). Microscopically the central lesion was well demarcated from the surrounding chorangioma, but unencapsulated (Fig. 2C). Within the blood-filled channels were islands of heterogeneous hematopoietic tissue, consistent with extramedullary hematopoiesis (Fig. 2D). No portal triads or bile ductules were seen. Immunohistochemical evaluation with CD34 showed strong immunoreactivity in the vascular channels within the chorangioma (Fig. 3A). In contrast, the epithelioid cells and hematopoietic elements of the central lesion were negative. Immunostaining with Vimentin strongly highlighted the vascular channels and stroma of the chorangioma but was negative in the adjacent epithelioid cells (Fig. 3B). In contrast, staining with Hep-par 1 showed striking immunoreactivity in the epithelioid cells but none in the chorangioma cells (Fig. 3C). Positive staining was also seen in the epithelioid cells with pancytokeratin cocktail (Fig. 3D), high-molecular weight cytokeratin (CK 903), and Alpha-1 Antitrypsin. Immunostaining with CK 7 showed no positivity within the liver tissue or in the chorangioma, confirming the absence of bile ductules and portal triads. This constellation of histologic and immunohistochemical features is consistent with benign liver tissue and supports a diagnosis of a hepatic adenoma.
DISCUSSION Primary nontrophoblastic tumors of the placenta are uncommon, and of these, chorangioma is the most common [2]. Chorangiomas were observed in 0.51% of examined placentas over a 10-year period in a recent study [3]. The lesion is most common in placentas corresponding to a 32to 37-week gestation and is increased in preeclamptic
Figure 1. Formalin-fixed section of placenta showing larger subchorionic chorangioma (open arrows) containing a central smaller gray-white hepatic adenoma (solid black arrows).
Figure 2. A. Blood-filled channels in chorangioma (hematoxylin and eosin [H&E], 3200). B. Cords of epithelioid cells in larger nodule (H&E, 3200). C. Sharp interface between smaller nodule (right) and larger (left) (H&E, 3200). D. Islands of hematopoietic cells between the epithelioid cells in the hepatic adenoma (H&E, 3400).
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Figure 3. A. CD34 immunostain highlighting vascular channels (3200). B. Vimentin immunohistochemical (IHC) positivity within cells of the larger nodule (left) but not in the smaller one (right) (3200). C. Hep-par1 IHC positivity within epithelioid cells of the smaller nodule (below) but not in the cells of the larger one (above) (3200). D. Pancytokeratin IHC positivity within epithelioid cells of the smaller nodule (right) but not in the cells of the larger one (left) (3200).
patients and twin gestations. Most are located subchorionically or marginally on the placenta. Microscopically, 2 subtypes have been described, angiomatous and cellular, based on the amount of accompanying stroma. The placental hepatocellular adenoma was first described by Chen and colleagues [4] and subsequently studied by Vescouli and Agamanolis [5] and Khalifa and colleagues [6]. The lesion is extremely rare and histologically consists of benign fetal-type liver tissue without portal areas or well-defined canaliculi. Foci of extramedullary hematopoiesis appear to be a characteristic finding. The histogenesis of this lesion has been debated, with candidates including heterotopic tissue, monomorphic teratomas, and fetus amorphous. These putative histogeneses are based primarily on the lesion’s typical location beneath the chorion [4]. Most evidence supports a true adenoma histogenesis, presumably arising from displaced yolk sac elements [6]. Coexistent neoplasms arising within the same organ or body site are rare but have been widely described. Their patho-etiologies often times are uncertain; however, in some cases, their coexistence may reflect a manifestation of a syndrome or germ line mutation (such as neurofibromatosis) or the effects of carcinogenic agents (such as ionizing radiation in lung neoplasms).
424
T.S. DENAPOLI
We believe that this case illustrates the coexistence of 2 benign neoplastic processes occurring in 1 of 2 diamniotic dichorionic twin placentas. The larger lesion shows features of a chorangioma. Located within the interior of the chorangioma was a 2nd focus of benign liver tissue, with foci of extramedullary hematopoiesis but lacking portal triads. These features are identical to those described as the hepatocellular adenoma. Thus, this case illustrates a unique presentation of 2 uncommon lesions in a single placenta. The clinical significance of these dual benign neoplasms is unclear but appears to be innocuous. The male twin neonates had unremarkable gestations, deliveries, and postnatal courses. Both were discharged 5 days following birth. The mother’s pregnancy, labor, delivery, and postpartum clinical course were also unremarkable. Although intermediate-size chorangiomas have been associated with intrauterine growth retardation [7], the twins’ birth weights and growth parameters were comparable and within the 25– 50th percentile for gestation length. Although it is rare, no untoward outcomes have been described with placental hepatic adenomas, a feature illustrated in this case.
CONCLUSION We present a case of coexistent placental chorangioma and hepatic adenoma, presenting grossly as a single discrete
nodule in 1 of 2 placentas from a diamnionic dichorionic twin gestation. Immunohistochemical staining confirmed the histogeneses of both lesions. These lesions did not appear to have any adverse effect on the gestation, birth, and postnatal courses of the twins and their mother. The innocuous nature of these coexistent lesions is consistent with the reported clinical outcomes in both of their dual components.
3.
4. 5.
REFERENCES
6.
1. Pinar H, Sung CJ, Oyer CE, et al. Reference values for singleton and twin placental weights. Pediatr Pathol Lab Med 1996;16:904. 2. Kraus FT, Redline RW, Gersell DJ, et al. Tumor-like lesions and metastatic neoplasms. In: Kraus FT, Redline RW, Gersell DJ, et al., eds. Placenta Pathology. Atlas of Nontumor Pathology: Placental
7.
Pathology First Series, Fascicle 3. Washington, DC: American Registry of Pathology in Collaboration with the Armed Forces Institute of Pathology, 2004;239–248. Orgino S, Redline RW. Villous capillary lesions of the placenta: distinctions between chorangioma, chorangiomatosis, and chorangiosis. Hum Pathol 2000;31:945–954. Chen KTK, Ma CK, Kassel SH. Hepatocellular adenoma of the placenta. Am J Surg Pathol 1986;10:436–440. Vescouli Z, Agamanolis D. Benign hepatocellular tumor of the placenta. Am J Surg Pathol 1998;22:355–359. Khalifa MA, Gersell DJ. Hepatic (hepatocellular) adenoma of the placenta: a study of four cases. Int J Gynecol Pathol 1998;17: 241–244. Mucitelli DR, Charles EZ, Kraus FT. Chorio-angioma of intermediate size and intrauterine growth retardation. Pathol Res Pract 1990;1986: 455–458.
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Coexistent Chorangioma and Hepatic Adenoma in One Twin Placenta: A Case Report and Review of the Literature THOMAS S. DENAPOLI* Department of Pathology, Children’s Hospital of San Antonio, San Antonio, TX, USA
Received December 30, 2014; accepted July 14, 2015; published online July 17, 2015.
ABSTRACT Primary nontrophoblastic tumors of a placenta are very uncommon, with the majority being of vascular origin, such as chorangiomas and chorangiomatosis. Rare examples of tumor-like collections of liver tissue, morphologically consistent with hepatocellular adenomas, have been reported. We report the co-occurrence of a chorangioma and hepatic adenoma as a grossly single lesion on the fetal surface of a diamniotic dichorionic twin placenta. Key words: chorangioma, coexistent tumors, hepatic adenoma, placenta
CASE REPORT Two discrete placental discs, each with a trivessel cord and connected by thin glistening membranes, were received in formalin following the uncomplicated vaginal delivery of infant males from a 32-year-old G3P2 African-American mother following a 35-week gestation. The pregnancy had been complicated by gestational hypertension. Twin A weighed 2180 g (26–50th percentile) and had APGAR scores of 8 and 9 at 1 and 5 minutes, respectively. Twin B weighed 2220 g (26–50th percentile) and had APGAR scores of 7 and 9 at 1 and 5 minutes, respectively. The discrete single-disc placenta A weighed 308 g and was grossly unremarkable. Singledisc placenta B weighed 301 g. The combined placental weight was 609 g, lying between the 10th and 25th percentiles for twin placentas for a 35-week gestation [1]. Sectioning of placenta B revealed a 4.5 3 3.5 3 3.5-cm sharply demarcated solid nodule of tan-pink rubbery tissue subjacent to the chorioamnion of the chorionic plate (Fig. 1). Located centrally within this nodule was an ill-defined area of glistening gray-white tissue measuring 1.5 cm in greatest dimension. Histologic evaluation of the larger sharply demarcated nodule showed classic findings of a chorangioma *Corresponding author, e-mail: [email protected]
consisting of a proliferation of small vessels containing erythrocytes separated by bland fibroblastic-like stroma (Fig. 2A). Scattered throughout the nodule were larger vessels with thick walls. In contrast, the central poorly defined gray-white area noted macroscopically consisted of an unencapsulated lobular proliferation of eosinophilic polygonal epithelioid cells arranged in vague columns and nests, separated by blood-filled channels (Fig. 2B). Microscopically the central lesion was well demarcated from the surrounding chorangioma, but unencapsulated (Fig. 2C). Within the blood-filled channels were islands of heterogeneous hematopoietic tissue, consistent with extramedullary hematopoiesis (Fig. 2D). No portal triads or bile ductules were seen. Immunohistochemical evaluation with CD34 showed strong immunoreactivity in the vascular channels within the chorangioma (Fig. 3A). In contrast, the epithelioid cells and hematopoietic elements of the central lesion were negative. Immunostaining with Vimentin strongly highlighted the vascular channels and stroma of the chorangioma but was negative in the adjacent epithelioid cells (Fig. 3B). In contrast, staining with Hep-par 1 showed striking immunoreactivity in the epithelioid cells but none in the chorangioma cells (Fig. 3C). Positive staining was also seen in the epithelioid cells with pancytokeratin cocktail (Fig. 3D), high-molecular weight cytokeratin (CK 903), and Alpha-1 Antitrypsin. Immunostaining with CK 7 showed no positivity within the liver tissue or in the chorangioma, confirming the absence of bile ductules and portal triads. This constellation of histologic and immunohistochemical features is consistent with benign liver tissue and supports a diagnosis of a hepatic adenoma.
DISCUSSION Primary nontrophoblastic tumors of the placenta are uncommon, and of these, chorangioma is the most common [2]. Chorangiomas were observed in 0.51% of examined placentas over a 10-year period in a recent study [3]. The lesion is most common in placentas corresponding to a 32to 37-week gestation and is increased in preeclamptic
Figure 1. Formalin-fixed section of placenta showing larger subchorionic chorangioma (open arrows) containing a central smaller gray-white hepatic adenoma (solid black arrows).
Figure 2. A. Blood-filled channels in chorangioma (hematoxylin and eosin [H&E], 3200). B. Cords of epithelioid cells in larger nodule (H&E, 3200). C. Sharp interface between smaller nodule (right) and larger (left) (H&E, 3200). D. Islands of hematopoietic cells between the epithelioid cells in the hepatic adenoma (H&E, 3400).
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Figure 3. A. CD34 immunostain highlighting vascular channels (3200). B. Vimentin immunohistochemical (IHC) positivity within cells of the larger nodule (left) but not in the smaller one (right) (3200). C. Hep-par1 IHC positivity within epithelioid cells of the smaller nodule (below) but not in the cells of the larger one (above) (3200). D. Pancytokeratin IHC positivity within epithelioid cells of the smaller nodule (right) but not in the cells of the larger one (left) (3200).
patients and twin gestations. Most are located subchorionically or marginally on the placenta. Microscopically, 2 subtypes have been described, angiomatous and cellular, based on the amount of accompanying stroma. The placental hepatocellular adenoma was first described by Chen and colleagues [4] and subsequently studied by Vescouli and Agamanolis [5] and Khalifa and colleagues [6]. The lesion is extremely rare and histologically consists of benign fetal-type liver tissue without portal areas or well-defined canaliculi. Foci of extramedullary hematopoiesis appear to be a characteristic finding. The histogenesis of this lesion has been debated, with candidates including heterotopic tissue, monomorphic teratomas, and fetus amorphous. These putative histogeneses are based primarily on the lesion’s typical location beneath the chorion [4]. Most evidence supports a true adenoma histogenesis, presumably arising from displaced yolk sac elements [6]. Coexistent neoplasms arising within the same organ or body site are rare but have been widely described. Their patho-etiologies often times are uncertain; however, in some cases, their coexistence may reflect a manifestation of a syndrome or germ line mutation (such as neurofibromatosis) or the effects of carcinogenic agents (such as ionizing radiation in lung neoplasms).
424
T.S. DENAPOLI
We believe that this case illustrates the coexistence of 2 benign neoplastic processes occurring in 1 of 2 diamniotic dichorionic twin placentas. The larger lesion shows features of a chorangioma. Located within the interior of the chorangioma was a 2nd focus of benign liver tissue, with foci of extramedullary hematopoiesis but lacking portal triads. These features are identical to those described as the hepatocellular adenoma. Thus, this case illustrates a unique presentation of 2 uncommon lesions in a single placenta. The clinical significance of these dual benign neoplasms is unclear but appears to be innocuous. The male twin neonates had unremarkable gestations, deliveries, and postnatal courses. Both were discharged 5 days following birth. The mother’s pregnancy, labor, delivery, and postpartum clinical course were also unremarkable. Although intermediate-size chorangiomas have been associated with intrauterine growth retardation [7], the twins’ birth weights and growth parameters were comparable and within the 25– 50th percentile for gestation length. Although it is rare, no untoward outcomes have been described with placental hepatic adenomas, a feature illustrated in this case.
CONCLUSION We present a case of coexistent placental chorangioma and hepatic adenoma, presenting grossly as a single discrete
nodule in 1 of 2 placentas from a diamnionic dichorionic twin gestation. Immunohistochemical staining confirmed the histogeneses of both lesions. These lesions did not appear to have any adverse effect on the gestation, birth, and postnatal courses of the twins and their mother. The innocuous nature of these coexistent lesions is consistent with the reported clinical outcomes in both of their dual components.
3.
4. 5.
REFERENCES
6.
1. Pinar H, Sung CJ, Oyer CE, et al. Reference values for singleton and twin placental weights. Pediatr Pathol Lab Med 1996;16:904. 2. Kraus FT, Redline RW, Gersell DJ, et al. Tumor-like lesions and metastatic neoplasms. In: Kraus FT, Redline RW, Gersell DJ, et al., eds. Placenta Pathology. Atlas of Nontumor Pathology: Placental
7.
Pathology First Series, Fascicle 3. Washington, DC: American Registry of Pathology in Collaboration with the Armed Forces Institute of Pathology, 2004;239–248. Orgino S, Redline RW. Villous capillary lesions of the placenta: distinctions between chorangioma, chorangiomatosis, and chorangiosis. Hum Pathol 2000;31:945–954. Chen KTK, Ma CK, Kassel SH. Hepatocellular adenoma of the placenta. Am J Surg Pathol 1986;10:436–440. Vescouli Z, Agamanolis D. Benign hepatocellular tumor of the placenta. Am J Surg Pathol 1998;22:355–359. Khalifa MA, Gersell DJ. Hepatic (hepatocellular) adenoma of the placenta: a study of four cases. Int J Gynecol Pathol 1998;17: 241–244. Mucitelli DR, Charles EZ, Kraus FT. Chorio-angioma of intermediate size and intrauterine growth retardation. Pathol Res Pract 1990;1986: 455–458.
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