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Kaposiform hemangioendothelioma in an adult spleen: An unusual presentation
Human Pathology: Case Reports 10 (2017) 15–17
Contents lists available at ScienceDirect
Human Pathology: Case Reports journal homepage: http://www.humanpathologycasereports.com
Case Report
Kaposiform hemangioendothelioma in an adult spleen: An unusual presentation Ahmed A. Abdulrahman, MD, Jie Yan, MD, PhD, J. Steve Hou, MD ⁎ Drexel University College of Medicine, Department of Pathology, 245 N 15th Street, MS 435, Philadelphia, PA, USA
a r t i c l e
i n f o
Article history: Received 28 December 2016 Received in revised form 12 April 2017 Accepted 13 April 2017 Available online xxxx
a b s t r a c t Kaposiform hemangioendothelioma (KHE) is a rare vascular neoplasm typically seen in skin and soft tissue of extremities in infants and children. Although visceral or adult KHE is extremely rare, several cases have been reported. We describe an unusual case of KHE in a 38 year old female who presented with a 2 year history of left upper quadrant pain, splenomegaly and portal venous thrombosis. An extensive workup was not conclusive and revealed only a JAK2 mutation on peripheral blood. This finding coupled with splenomegaly raised suspicion for an early myeloproliferative disorder. Splenectomy was performed for symptomatic relief. No discrete masses or lesions were grossly identified. Microscopically, the spleen was completely replaced by a neoplastic spindle cell proliferation. The diagnosis was KHE replacing the entire spleen. Two reactive lymph nodes were found in the splenic hilum, free of tumor. Follow up 2 years after splenectomy revealed no sign of recurrence or metastasis. To the best of our knowledge, this is the first report of incidental KHE arising in and completely replacing the entire spleen. Despite the long standing disease, no extrasplenic invasion or lymph node metastasis was present, suggesting an overall benign neoplastic process. © 2017 The Authors. Published by Elsevier Inc. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/).
1. Introduction Kaposiform hemangioendothelioma (KHE) is a rare vascular neoplasm of intermediate (borderline) malignant potential. It was first described in children in 1993 by Zukerberg et al and presents common features between hemangioma and Kaposi sarcoma [1]. The majority of patients are infants and children with a cutaneous vascular lesion, typically extending through the subcutis to involve underlying skeletal muscle [1,2]. Fewer cases present in deep locations such as the retroperitoneum or thoracic cavity. Various names were used including Kaposi-like infantile hemangioendothelioma and hemangioma with Kaposi sarcoma-like features. Overall, fewer than 160 cases have been reported in the literature. Moreover, KHE in adolescents and adults is very rare and less than 20 cases have been reported [3]. KHE typically exhibits a locally aggressive behavior but lacks distant metastasis. In general, it is not as infiltrative as Kaposi's sarcoma. Those involving skin and subcutaneous tissues are usually surrounded by dense hyaline fibrosis, whereas those within the body cavity tend to involve adjacent structures such as intestine, bile ducts, pancreas, parathyroid, and bone [1]. Two cases reportedly involved perinodal soft
⁎ Corresponding author at: Department of Pathology and Laboratory Medicine, Drexel University College of Medicine, 245 N 15th Street, MS 435, Philadelphia, PA, USA. Tel.: +1 215 762 3753; fax: +1 215 762 7002. E-mail addresses: [email protected] (A.A. Abdulrahman), [email protected] (J. Yan), [email protected] (J.S. Hou).
tissue; in one of these, lymph nodes were several centimeters proximal to the main mass [1]. This justifies the continuing classification of KHE as a lesion of intermediate malignancy. KHE is often associated with Kasabach–Merritt phenomenon (KMP), a consumptive coagulopathy characterized by profound thrombocytopenia, life-threatening hemorrhage and lymphangiomatosis [4–6]. KMP is present in N50% of patients with KHE and may result in death in 12%–30% of cases. Younger patients are more likely to have KMP (77% versus 11% in adults). KMP appears to be due to platelet trapping and activation within the lesion itself, proven by normalization of platelet counts and D-dimers after resection [3]. The differential diagnosis of KHE includes other vascular tumors, namely capillary and anastomosing hemangiomas, spindle cell hemangioma, acquired tufted angioma, as well as Kaposi sarcoma and angiosarcoma. Other differentials that are limited only to the spleen include littoral cell angioma and sclerosing angiomatoid nodular transformation. The treatment is limited by lack of experience due to the relative rarity of this neoplasm. The most effective therapy is complete excision. For unresectable and extensive lesions with KMP, corticosteroids, alpha-interferon, chemotherapy and radiation therapy have all been reported with varying success [2]. 2. Case presentation A 38 year old African American female with a past medical history of portal venous thrombosis and splenomegaly for 2 years presented with
http://dx.doi.org/10.1016/j.ehpc.2017.04.002 2214-3300/© 2017 The Authors. Published by Elsevier Inc. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/).
16
A.A. Abdulrahman et al. / Human Pathology: Case Reports 10 (2017) 15–17
Fig. 1. A. Kaposiform areas in top half, capillary sized vessels with attenuated lumina in bottom half with scant residual white pulp (H&E, 4×), B. Spindled and nodular areas (H&E, 10×), C. Area with larger gaped capillaries (H&E, 10×), D. Hyperchromatic, spindled endothelial cells with extravasated RBCs (H&E, 40×), E. High power of glomeruloid area showing epithelioid endothelial cells with cytoplasmic lumina (H&E, 40×).
fatigue, left upper quadrant pain and tenderness. Lab testing including CBC and CMP was within normal limits, except for anemia (Hgb: 9.3 g/dL) with normal WBC and platelet counts. Imaging showed noncirrhotic portal hypertension and splenomegaly with a 1 cm increment in splenic size compared to prior CT with evidence of new infarcts. In addition, portal, splenic and superior mesenteric venous thromboses were identified. There was no family history of hypercoagulable state. These findings triggered an extensive thrombophilia workup including paroxysmal nocturnal hemoglobinuria (PNH) testing which was negative and revealed only a JAK2 mutation on peripheral blood. This finding, coupled with splenomegaly, raised suspicion for an early myeloproliferative disorder. A bone marrow biopsy showed hypercellular marrow (70%–80%) with no evidence of myeloproliferative disorder. Splenectomy was performed for symptomatic relief. The spleen measured 14.5 cm in greatest dimension and weighed 408 g (normal range: 125–200 g). It showed a firm, dark red cut surface with intact smooth capsule. No discrete masses or lesions were identified. Microscopically, the splenic architecture was entirely effaced with diffuse and complete replacement by a neoplastic spindle cell proliferation, forming vague slit-like vascular spaces in a nodular growth
pattern, separated by hypocellular hyalinized fibrous bands (Fig. 1). Some areas showed glomeruloid capillary proliferation and gaping vascular lumens containing red blood cells and microthrombi. The tumor cells showed mild nuclear pleomorphism, no significant cytologic atypia, and rare mitotic activity (1/10 HPF). Areas of hemorrhage, hemosiderin deposits, infiltration by lymphocytes and Gamna–Gandy bodies were present. Immunohistochemical stains were performed. The tumor cells are positive for CD31, CD34 and VWF. SMA highlights the pericytes around the vascular spaces. CD3 and CD8 highlight T lymphocytes. CD20, PAX5 and CD21 highlight B lymphocytes in the scant residual white pulps. CD68 highlights macrophages. HHV8 immunostain is negative (Fig. 2). The final diagnosis was KHE replacing the entire spleen. Two reactive lymph nodes were found in the splenic hilum, free of tumor. Follow up 2 years after splenectomy revealed no sign of recurrence or metastasis. 3. Discussion This is an unusual case of visceral KHE in an adult female presenting with a 2 year history of portal venous thrombosis and splenomegaly of
Fig. 2. Neoplastic endothelial cells expressing CD31, CD34 and VWF. SMA stains the pericytes encircling unstained endothelial cells. HHV8 immunostaining is negative.
A.A. Abdulrahman et al. / Human Pathology: Case Reports 10 (2017) 15–17
unknown etiology. Imaging of the spleen did not reveal any masses or lesions. An extensive workup was not conclusive. Clinically, splenomegaly was thought to be due to portal venous thrombosis or to an underlying myeloproliferative disorder. Splenectomy was performed for symptomatic relief and incidental KHE was identified as the cause of splenomegaly. The overall prognosis of KHE is mainly related to the size, anatomic site and extent of neoplasm. It is also greatly influenced by the associated KMP and coagulopathy, which are the major causes of death. Retroperitoneal lesions or visceral forms are associated with a worse prognosis, with a reported mortality of up to 30% due to bleeding or tumor invasion into vital organs [3]. In the original case series by Zukerberg et al, it was reported that KHE displays aggressive local behavior, with uncertain distant metastatic potential. Four of the tumors in their series grew in a locally destructive fashion; one tumor extended proximally up the arm to involve the perinodal soft tissue. The number and distribution of the masses suggested extensive local metastasis rather than simply contiguous extension [1]. However, no patient in that series, or in any reported case in the literature, has developed distant metastasis. KHE in adults was first reported in 1997 by Mentzel et al in a series of three cases [7]. They reemphasized that the locally aggressive behavior in many cases warranted the designation of hemangioendothelioma, implying intermediate malignant potential, although the precise biologic behavior of KHE (in terms of metastatic capability, if any) remained uncertain. At present, whether the terms malignant or borderline should be applied to KHE is still debatable, because it has more in common with fibromatosis or angiomatosis than with a true (metastasizing) malignancy [7]. Yu et al in 2011 reported the first case of KHE of the spleen in a 36 year old female who presented with abdominal discomfort [8]. Imaging showed a 12.6 cm hypervascular splenic mass that was suggestive of a hemangioma. Splenectomy showed the poorly circumscribed mass as KHE. Follow up 6 months later showed no evidence of disease. Subsequently, another case of KHE of the spleen was reported in a male neonate and was identified on a prenatal ultrasound at 34 weeks gestation showing a 6.5 cm splenic mass [9]. Unlike our case and the aforementioned case, KMP was present. On postnatal day 5, splenectomy was performed showing the mass as KHE, and KMP subsequently resolved.
17
Our patient had a large visceral tumor (14.5 cm). It is likely that the natural history of KHE in this unusual location was highly favorable due to the amenability of splenic tumors to complete surgical resection. To the best of our knowledge, this is the first report of incidental KHE arising in and completely replacing the entire spleen. Despite the long standing disease and complete splenic replacement, no extrasplenic invasion or lymph node metastasis was present, suggesting an overall benign neoplastic process. 4. Conclusion Although extremely rare, KHE should be considered in the differential diagnosis of vascular tumors in all sites and ages. Additional studies and case series are needed to better classify its neoplastic nature and malignant potential. References [1] L.R. Zukerberg, B.J. Nickoloff, S.W. Weiss, Kaposiform hemangioendothelioma of infancy and childhood: an aggressive neoplasm associated with Kasabach–Merritt syndrome and lymphangiomatosis, Am. J. Surg. Pathol. 17 (1993) 321–328. [2] L.L. Lyons, P.E. North, F. Mac-Moune Lai, M.H. Stoler, A.L. Folpe, S.W. Weiss, Kaposiform hemangioendothelioma: a study of 33 cases emphasizing its pathologic, immunophenotypic, and biologic uniqueness from juvenile hemangioma, Am. J. Surg. Pathol. 28 (5) (2004 May) 559–568. [3] F.D. Costa, A.L. Folpe, Intratesticular kaposiform hemangioendothelioma in adults: a report of two cases, J. Clin. Pathol. 66 (7) (2013) 623–626. [4] M. Sarkar, J.B. Mulliken, H.P. Kozakewich, et al., Thrombocytopenic coagulopathy (Kasabach–Merritt phenomenon) is associated with kaposiform hemangioendothelioma and not with common infantile hemangioma, Plast. Reconstr. Surg. 100 (6) (1997) 1377–1386. [5] O. Enjolras, J.B. Mulliken, M. Wassef, et al., Residual lesions after Kasabach–Merritt phenomenon in 41 patients, J. Am. Acad. Dermatol. 42 (2 Pt 1) (2000) 225–235. [6] V. Rodriguez, A. Lee, P.M. Witman, et al., Kasabach–Merritt phenomenon: case series and retrospective review of the mayo clinic experience, J. Pediatr. Hematol. Oncol. 31 (7) (2009) 522–526. [7] T. Mentzel, G. Mazzoleni, A.P. Dei Tos, et al., Kaposiform hemangioendothelioma in adults. Clinicopathologic and immunohistochemical analysis of three cases, Am. J. Clin. Pathol. 108 (4) (1997) 450–455. [8] L. Yu, S.J. Yang, Kaposiform hemangioendothelioma of the spleen in an adult: an initial case report, Pathol. Oncol. Res. 17 (4) (2011) 969–972. [9] S.A. Shabtaie, B. Wang, M. Owyong, C. Ruiz-Mesa, F.F. Corrales-Medina, C.P. Rojas, et al., Neonatal kaposiform hemangioendothelioma of the spleen associated with Kasabach–Merritt phenomenon, J. Pediatr. Surg. 51 (6) (2016) 1047–1050.
Contents lists available at ScienceDirect
Human Pathology: Case Reports journal homepage: http://www.humanpathologycasereports.com
Case Report
Kaposiform hemangioendothelioma in an adult spleen: An unusual presentation Ahmed A. Abdulrahman, MD, Jie Yan, MD, PhD, J. Steve Hou, MD ⁎ Drexel University College of Medicine, Department of Pathology, 245 N 15th Street, MS 435, Philadelphia, PA, USA
a r t i c l e
i n f o
Article history: Received 28 December 2016 Received in revised form 12 April 2017 Accepted 13 April 2017 Available online xxxx
a b s t r a c t Kaposiform hemangioendothelioma (KHE) is a rare vascular neoplasm typically seen in skin and soft tissue of extremities in infants and children. Although visceral or adult KHE is extremely rare, several cases have been reported. We describe an unusual case of KHE in a 38 year old female who presented with a 2 year history of left upper quadrant pain, splenomegaly and portal venous thrombosis. An extensive workup was not conclusive and revealed only a JAK2 mutation on peripheral blood. This finding coupled with splenomegaly raised suspicion for an early myeloproliferative disorder. Splenectomy was performed for symptomatic relief. No discrete masses or lesions were grossly identified. Microscopically, the spleen was completely replaced by a neoplastic spindle cell proliferation. The diagnosis was KHE replacing the entire spleen. Two reactive lymph nodes were found in the splenic hilum, free of tumor. Follow up 2 years after splenectomy revealed no sign of recurrence or metastasis. To the best of our knowledge, this is the first report of incidental KHE arising in and completely replacing the entire spleen. Despite the long standing disease, no extrasplenic invasion or lymph node metastasis was present, suggesting an overall benign neoplastic process. © 2017 The Authors. Published by Elsevier Inc. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/).
1. Introduction Kaposiform hemangioendothelioma (KHE) is a rare vascular neoplasm of intermediate (borderline) malignant potential. It was first described in children in 1993 by Zukerberg et al and presents common features between hemangioma and Kaposi sarcoma [1]. The majority of patients are infants and children with a cutaneous vascular lesion, typically extending through the subcutis to involve underlying skeletal muscle [1,2]. Fewer cases present in deep locations such as the retroperitoneum or thoracic cavity. Various names were used including Kaposi-like infantile hemangioendothelioma and hemangioma with Kaposi sarcoma-like features. Overall, fewer than 160 cases have been reported in the literature. Moreover, KHE in adolescents and adults is very rare and less than 20 cases have been reported [3]. KHE typically exhibits a locally aggressive behavior but lacks distant metastasis. In general, it is not as infiltrative as Kaposi's sarcoma. Those involving skin and subcutaneous tissues are usually surrounded by dense hyaline fibrosis, whereas those within the body cavity tend to involve adjacent structures such as intestine, bile ducts, pancreas, parathyroid, and bone [1]. Two cases reportedly involved perinodal soft
⁎ Corresponding author at: Department of Pathology and Laboratory Medicine, Drexel University College of Medicine, 245 N 15th Street, MS 435, Philadelphia, PA, USA. Tel.: +1 215 762 3753; fax: +1 215 762 7002. E-mail addresses: [email protected] (A.A. Abdulrahman), [email protected] (J. Yan), [email protected] (J.S. Hou).
tissue; in one of these, lymph nodes were several centimeters proximal to the main mass [1]. This justifies the continuing classification of KHE as a lesion of intermediate malignancy. KHE is often associated with Kasabach–Merritt phenomenon (KMP), a consumptive coagulopathy characterized by profound thrombocytopenia, life-threatening hemorrhage and lymphangiomatosis [4–6]. KMP is present in N50% of patients with KHE and may result in death in 12%–30% of cases. Younger patients are more likely to have KMP (77% versus 11% in adults). KMP appears to be due to platelet trapping and activation within the lesion itself, proven by normalization of platelet counts and D-dimers after resection [3]. The differential diagnosis of KHE includes other vascular tumors, namely capillary and anastomosing hemangiomas, spindle cell hemangioma, acquired tufted angioma, as well as Kaposi sarcoma and angiosarcoma. Other differentials that are limited only to the spleen include littoral cell angioma and sclerosing angiomatoid nodular transformation. The treatment is limited by lack of experience due to the relative rarity of this neoplasm. The most effective therapy is complete excision. For unresectable and extensive lesions with KMP, corticosteroids, alpha-interferon, chemotherapy and radiation therapy have all been reported with varying success [2]. 2. Case presentation A 38 year old African American female with a past medical history of portal venous thrombosis and splenomegaly for 2 years presented with
http://dx.doi.org/10.1016/j.ehpc.2017.04.002 2214-3300/© 2017 The Authors. Published by Elsevier Inc. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/).
16
A.A. Abdulrahman et al. / Human Pathology: Case Reports 10 (2017) 15–17
Fig. 1. A. Kaposiform areas in top half, capillary sized vessels with attenuated lumina in bottom half with scant residual white pulp (H&E, 4×), B. Spindled and nodular areas (H&E, 10×), C. Area with larger gaped capillaries (H&E, 10×), D. Hyperchromatic, spindled endothelial cells with extravasated RBCs (H&E, 40×), E. High power of glomeruloid area showing epithelioid endothelial cells with cytoplasmic lumina (H&E, 40×).
fatigue, left upper quadrant pain and tenderness. Lab testing including CBC and CMP was within normal limits, except for anemia (Hgb: 9.3 g/dL) with normal WBC and platelet counts. Imaging showed noncirrhotic portal hypertension and splenomegaly with a 1 cm increment in splenic size compared to prior CT with evidence of new infarcts. In addition, portal, splenic and superior mesenteric venous thromboses were identified. There was no family history of hypercoagulable state. These findings triggered an extensive thrombophilia workup including paroxysmal nocturnal hemoglobinuria (PNH) testing which was negative and revealed only a JAK2 mutation on peripheral blood. This finding, coupled with splenomegaly, raised suspicion for an early myeloproliferative disorder. A bone marrow biopsy showed hypercellular marrow (70%–80%) with no evidence of myeloproliferative disorder. Splenectomy was performed for symptomatic relief. The spleen measured 14.5 cm in greatest dimension and weighed 408 g (normal range: 125–200 g). It showed a firm, dark red cut surface with intact smooth capsule. No discrete masses or lesions were identified. Microscopically, the splenic architecture was entirely effaced with diffuse and complete replacement by a neoplastic spindle cell proliferation, forming vague slit-like vascular spaces in a nodular growth
pattern, separated by hypocellular hyalinized fibrous bands (Fig. 1). Some areas showed glomeruloid capillary proliferation and gaping vascular lumens containing red blood cells and microthrombi. The tumor cells showed mild nuclear pleomorphism, no significant cytologic atypia, and rare mitotic activity (1/10 HPF). Areas of hemorrhage, hemosiderin deposits, infiltration by lymphocytes and Gamna–Gandy bodies were present. Immunohistochemical stains were performed. The tumor cells are positive for CD31, CD34 and VWF. SMA highlights the pericytes around the vascular spaces. CD3 and CD8 highlight T lymphocytes. CD20, PAX5 and CD21 highlight B lymphocytes in the scant residual white pulps. CD68 highlights macrophages. HHV8 immunostain is negative (Fig. 2). The final diagnosis was KHE replacing the entire spleen. Two reactive lymph nodes were found in the splenic hilum, free of tumor. Follow up 2 years after splenectomy revealed no sign of recurrence or metastasis. 3. Discussion This is an unusual case of visceral KHE in an adult female presenting with a 2 year history of portal venous thrombosis and splenomegaly of
Fig. 2. Neoplastic endothelial cells expressing CD31, CD34 and VWF. SMA stains the pericytes encircling unstained endothelial cells. HHV8 immunostaining is negative.
A.A. Abdulrahman et al. / Human Pathology: Case Reports 10 (2017) 15–17
unknown etiology. Imaging of the spleen did not reveal any masses or lesions. An extensive workup was not conclusive. Clinically, splenomegaly was thought to be due to portal venous thrombosis or to an underlying myeloproliferative disorder. Splenectomy was performed for symptomatic relief and incidental KHE was identified as the cause of splenomegaly. The overall prognosis of KHE is mainly related to the size, anatomic site and extent of neoplasm. It is also greatly influenced by the associated KMP and coagulopathy, which are the major causes of death. Retroperitoneal lesions or visceral forms are associated with a worse prognosis, with a reported mortality of up to 30% due to bleeding or tumor invasion into vital organs [3]. In the original case series by Zukerberg et al, it was reported that KHE displays aggressive local behavior, with uncertain distant metastatic potential. Four of the tumors in their series grew in a locally destructive fashion; one tumor extended proximally up the arm to involve the perinodal soft tissue. The number and distribution of the masses suggested extensive local metastasis rather than simply contiguous extension [1]. However, no patient in that series, or in any reported case in the literature, has developed distant metastasis. KHE in adults was first reported in 1997 by Mentzel et al in a series of three cases [7]. They reemphasized that the locally aggressive behavior in many cases warranted the designation of hemangioendothelioma, implying intermediate malignant potential, although the precise biologic behavior of KHE (in terms of metastatic capability, if any) remained uncertain. At present, whether the terms malignant or borderline should be applied to KHE is still debatable, because it has more in common with fibromatosis or angiomatosis than with a true (metastasizing) malignancy [7]. Yu et al in 2011 reported the first case of KHE of the spleen in a 36 year old female who presented with abdominal discomfort [8]. Imaging showed a 12.6 cm hypervascular splenic mass that was suggestive of a hemangioma. Splenectomy showed the poorly circumscribed mass as KHE. Follow up 6 months later showed no evidence of disease. Subsequently, another case of KHE of the spleen was reported in a male neonate and was identified on a prenatal ultrasound at 34 weeks gestation showing a 6.5 cm splenic mass [9]. Unlike our case and the aforementioned case, KMP was present. On postnatal day 5, splenectomy was performed showing the mass as KHE, and KMP subsequently resolved.
17
Our patient had a large visceral tumor (14.5 cm). It is likely that the natural history of KHE in this unusual location was highly favorable due to the amenability of splenic tumors to complete surgical resection. To the best of our knowledge, this is the first report of incidental KHE arising in and completely replacing the entire spleen. Despite the long standing disease and complete splenic replacement, no extrasplenic invasion or lymph node metastasis was present, suggesting an overall benign neoplastic process. 4. Conclusion Although extremely rare, KHE should be considered in the differential diagnosis of vascular tumors in all sites and ages. Additional studies and case series are needed to better classify its neoplastic nature and malignant potential. References [1] L.R. Zukerberg, B.J. Nickoloff, S.W. Weiss, Kaposiform hemangioendothelioma of infancy and childhood: an aggressive neoplasm associated with Kasabach–Merritt syndrome and lymphangiomatosis, Am. J. Surg. Pathol. 17 (1993) 321–328. [2] L.L. Lyons, P.E. North, F. Mac-Moune Lai, M.H. Stoler, A.L. Folpe, S.W. Weiss, Kaposiform hemangioendothelioma: a study of 33 cases emphasizing its pathologic, immunophenotypic, and biologic uniqueness from juvenile hemangioma, Am. J. Surg. Pathol. 28 (5) (2004 May) 559–568. [3] F.D. Costa, A.L. Folpe, Intratesticular kaposiform hemangioendothelioma in adults: a report of two cases, J. Clin. Pathol. 66 (7) (2013) 623–626. [4] M. Sarkar, J.B. Mulliken, H.P. Kozakewich, et al., Thrombocytopenic coagulopathy (Kasabach–Merritt phenomenon) is associated with kaposiform hemangioendothelioma and not with common infantile hemangioma, Plast. Reconstr. Surg. 100 (6) (1997) 1377–1386. [5] O. Enjolras, J.B. Mulliken, M. Wassef, et al., Residual lesions after Kasabach–Merritt phenomenon in 41 patients, J. Am. Acad. Dermatol. 42 (2 Pt 1) (2000) 225–235. [6] V. Rodriguez, A. Lee, P.M. Witman, et al., Kasabach–Merritt phenomenon: case series and retrospective review of the mayo clinic experience, J. Pediatr. Hematol. Oncol. 31 (7) (2009) 522–526. [7] T. Mentzel, G. Mazzoleni, A.P. Dei Tos, et al., Kaposiform hemangioendothelioma in adults. Clinicopathologic and immunohistochemical analysis of three cases, Am. J. Clin. Pathol. 108 (4) (1997) 450–455. [8] L. Yu, S.J. Yang, Kaposiform hemangioendothelioma of the spleen in an adult: an initial case report, Pathol. Oncol. Res. 17 (4) (2011) 969–972. [9] S.A. Shabtaie, B. Wang, M. Owyong, C. Ruiz-Mesa, F.F. Corrales-Medina, C.P. Rojas, et al., Neonatal kaposiform hemangioendothelioma of the spleen associated with Kasabach–Merritt phenomenon, J. Pediatr. Surg. 51 (6) (2016) 1047–1050.