Multifocal congenital hemangiopericytomas associated with Kasabach-Merritt syndrome

Congenital Infantile Fibrosarcoma Involving Pelvic Wall and Thigh Soft Tissues and Placenta, Presenting with Coagulopathy

Infantile fibrosarcoma (IF) is a well characterized pediatric malignancy marked by gene rearrangements involving members of the NTRK family. In this report, we present a case of IF that presented in the inguinal region-proximal thigh and was initially thought to be a kaposiform hemangioendothelioma (KHE) because it presented with a bleeding diathesis thought to be Kasabach-Merritt phenomenon (KMP). Subsequently, the placental examination showed a neoplasm in the perivascular-subendothelial space of stem villi, initially thought to be myofibromatosis. Ultimately, a biopsy of the thigh mass showed IF with an NTRK3-ETV6 fusion. Subsequent FISH analysis of the placenta showed an ETV6 rearrangement confirming that it was also IF. Review of the laboratory studies suggests that disseminated intravascular coagulation may have been more likely than KMP, highlighting the difficulty in making this distinction in some cases. We believe this to be the first report of an IF presenting in a soft tissue site and the placenta, and discuss the possible mechanisms that could have allowed the IF in the leg to spread to the placenta.

Case report: neonatal giant forehead hemangiopericytoma with a 5-year follow-up

RATIONALE

Hemangiopericytoma (HPC) is a rare pediatric neoplasm with a high risk of bleeding, aggressive growth and high early relapse rates. Surgical excision remains the mainstream treatment, while the functions of chemotherapy and radiotherapy remain controversial. In particular, an infantile giant extracranial HPC located in the forehead has never been reported.

PATIENT CONCERNS

A 3-day-old girl was delivered normally with a giant tumor localized mainly in the right frontal region. The surface of the mass was filled with vascularity.

DIAGNOSIS

According to the results of imaging and pathological examinations, the diagnosis was HPC grade II.

INTERVENTIONS

Gross total resection of the tumor and the invading partial frontal bone followed by skin scalp reconstruction was carried out without any blood transfusion.

OUTCOMES

No recurrence was identified during 5 years of follow-up. And better outcomes can be achieved without adjuvant therapy.

LESSONS

Multimodality imaging and a collaborative multidisciplinary approach are indispensable for the successful surgical management of infantile HPC, especially for giant tumors and their potential risk of life-threatening bleeding. Gross total resection is the optimal option for infantile HPC, and even without adjuvant therapy, it achieves better outcomes.

Multifocal Congenital Hemangiopericytoma

Congenital hemangiopericytoma (HPC) is a rare mesenchymal tumor with less aggressive behavior and a more favorable prognosis than similar tumors in adults. Multifocal presentation is even less common than isolated HPC and hence its clinical and histologic recognition may be challenging. A newborn infant with multifocal congenital HPC causing severe deformity but with a favorable outcome after chemotherapy and surgical removal is reported.

Management of hemangiomas and other vascular tumors

Vascular tumors of childhood are typically benign. The 4 most common types are infantile hemangioma (IH), congenital hemangioma (CH), kaposiform hemangioendothelioma (KHE), and pyogenic granuloma (PG). Vascular tumors must be differentiated from vascular malformations. Although tumors and malformations may appear as raised, blue, red, or purple lesions, their management differs significantly.

Infantile myofibroma or lymphatic malformation: differential diagnosis of neonatal cystic cervicofacial lesions

A 5-day-old male neonate was referred to our vascular anomalies center with a large cystic submandibular mass. History and physical examination and ultrasonographic results indicated the diagnosis to be macrocystic lymphatic malformation. Consequently, the child was treated with sclerotherapy and subtotal excision. The histopathological examination result showed that the lesion was infantile myofibroma. This diagnostic error was attributed to atypical features of infantile myofibroma in this child: unusually large cysts, rapid enlargement, and coagulopathy. This report expands the clinical spectrum of infantile myofibromatosis and suggests its consideration in the differential diagnosis of neonatal cystic cervicofacial lesions.

Congenital hemangiopericytoma in a neonate

Hemangiopericytoma is a rare malignant vascular tumor that usually occurs in adults. The occurrence of these tumors in infants, known as congenital or infantile hemangiopericytoma, is even rarer and their behavior may be more benign than the adult type. We describe a 1-day-old female neonate with congenital hemangiopericytoma, presenting with a right inguinal mass at birth. At the time of surgery, lymphangioma was suspected because of its appearance, fluid-filled multicystic content, and the high incidence of this disease in pediatric patients. Tumor excision was performed and hemangiopericytoma was diagnosed by histology. There was no tumor recurrence during 12 months of follow-up.

Kaposiform hemangioendothelioma without Kasabach-Merritt phenomenon

Kasabach-Merritt phenomenon is a serious coagulopathy associated with kaposiform hemangioendothelioma (KHE), tufted angioma, and possibly other vascular neoplasms. KHE presenting in the absence of Kasabach-Merritt phenomenon is rare, although tufted angioma frequently occurs without thrombocytopenia. We retrospectively reviewed 10 cases of KHE without Kasabach-Merritt phenomenon. The tumors appeared as soft tissue masses with the overlying skin being either normal, erythematous, or violaceous. There were no radiologic or microscopic differences in noncoagulopathic KHE as compared with coagulopathic KHE. Evidence of platelet trapping and hemosiderin deposition was seen histologically, despite normal serum platelet levels. All KHE were less than 8 cm in diameter, suggesting that tumors that grow no larger than this size are less likely to trap platelets in sufficient quantity to cause thrombocytopenia. Our series confirms that KHE appears with a wide spectrum of behavior and response to treatment. The decision as to whether or not to treat a noncoagulopathic KHE should be based on the size and location of the tumor and the possible side effects of therapy.

Neonate with a fibrosarcoma and consumptive coagulopathy

We report a case of a neonate with a congenital tumor on the left palm. The patient had a grapefruit-sized tumor and coagulopathy at birth and was presumed to have a hemangioendothelioma with associated Kasabach-Merritt phenomenon. When the tumor failed to respond to systemic steroids, a biopsy specimen was taken, revealing a fibrosarcoma. We describe this case to highlight the importance of including rare tumors, such as fibrosarcomas, in the clinical differential when evaluating a congenital tumor with associated coagulopathy. We discuss subtle differences in clinical presentations that might aid in differentiating vascular tumors from fibrosarcomas.

Thrombocytopenic coagulopathy (Kasabach-Merritt phenomenon) is associated with Kaposiform hemangioendothelioma and not with common infantile hemangioma

Children with a large vascular tumor and associated Kasabach-Merritt coagulopathy respond inconsistently to therapy and have a high mortality rate. For this reason, we undertook a retrospective study of 21 such patients, and focused on clinical, radiographic, and histopathologic features. The male to female ratio was 1:1.6. Tumor was noted at birth in 50 percent of patients; the remainder appeared throughout infancy. The location was cervicofacial (n = 2), shoulder/upper limb (n = 4), trunk including retroperitoneum (n = 11), and lower limb (n = 4). These tumors grew rapidly to large size and were characterized by cutaneous purpura, edema, and an advancing ecchymotic margin. In contrast to common hemangioma, magnetic resonance imaging showed diffuse enhancement with ill-defined margins, cutaneous thickening, stranding of subcutaneous fat, hemosiderin deposits, and small feeding and draining vessels. All tumors were Kaposiform hemangioendothelioma (KHE); none were infantile hemangioma. Light microscopy showed irregular lobules or sheets of poorly formed, small vascular channels infiltrating and entrapping normal tissues. Characteristic features included spindle-shaped endothelial cells, diminished pericytes and mast cells, microthrombi, and hemosiderin deposits. Wide endothelial intercellular gaps and incomplete basement membranes were seen by electron microscopy. Dilated, hyperplastic, lymphaticoid channels were prominent in one tumor. KHE in 14 infants was treated with interferon alpha-2a: 6 had accelerated regression; 2 had stabilization of growth; and 6 evidenced no response. The mortality rate was 24 percent (5 of 21); this included three infants with retroperitoneal KHE. Kasabach-Merritt phenomenon does not occur with common hemangioma. Rather it is associated with the more aggressive KHE and rarely with other vascular neoplasms. Variable response to current pharmacologic therapy underscores our inadequate knowledge of the pathogenesis of thrombocytopenia in KHE.

Congenital hemangiopericytoma/infantile myofibromatosis: radical surgery versus a conservative "wait and see" approach

Infantile/congenital hemangiopericytoma, although sharing many similar histological features with adult hemangiopericytoma, has a much better prognosis. Nevertheless, most cases described in the literature were pursued by radical surgery with or without adjuvant chemotherapy. We describe a neonate who presented with a huge mass in the right gluteus, 6 x 5 x 4 cm, and a small ventral abdominal mass. The masses were confirmed on biopsy according to light microscopy, immunohistochemistry, and electron microscopy as congenital hemangiopericytoma. They shrank spontaneously within 2 weeks and vanished within 2 months. We present a hypothesis that masses appearing in the neonatal period with this histology and with no life-endangering pressure on vital organs should routinely be dealt with conservatively.

Preoperative chemotherapy for congenital hemangiopericytoma and a review of the literature

PURPOSE

Malignant hemangiopericytoma is an uncommon tumor in the pediatric age group. A case of congenital hemangiopericytoma is presented with a review of the literature.

PATIENTS AND METHODS

A 2-month-old boy presented at birth with an enlarging posterior neck mass. Subsequent histopathologic studies showed findings consistent with hemangiopericytoma. Imaging studies demonstrated an extensive, infiltrative, vascular lesion not readily amenable to surgical resection. A pulmonary metastatic lesion was present.

RESULTS

Combined treatment using vincristine, doxorubicin, and cyclophosphamide given preoperatively resulted in a significant decrease in size of the primary tumor, allowing for resection without complication and resolution of the metastatic lesion.

CONCLUSION

Preoperative chemotherapy may have a significant role in the management of infants with malignant hemangiopericytoma.

Infants with Kasabach-Merritt syndrome do not have "true" hemangiomas

OBJECTIVE

In 1940 Kasabach and Merritt described an infant with a vascular anomaly, extensive purpura, and thrombocytopenia; they called his lesion "capillary hemangioma." Hemangioma is a benign tumor that grows in infancy and is characterized by proliferation of endothelial cells and regression during childhood. Although Kasabach-Merritt syndrome (KMS) is frequently mentioned as a possible complication of hemangioma, our experience suggests that the anatomic vascular lesion underlying the thrombocytopenia is not a "true," classic, involuting type of hemangioma of infancy and childhood.

STUDY DESIGN

We reviewed the clinical and hemostasis data and the response to treatment in 22 cases of KMS, and we analyzed the biopsy specimens of 15 of them.

RESULTS

Clinically none of the 22 patients had classic hemangioma. There was no female preponderance. All patients had severe thrombocytopenia (lowest platelet count = 3000/mm3) and consumption of fibrinogen. Histologically, none had the typical "capillary," involuting type of hemangioma of infancy: they exhibited either a tufted angioma or a kaposiform hemangioendothelioma pattern; all specimens also contained numerous abnormal lymphatic-like vessels; lymphatic malformation was the major component in two patients. The infants exhibited a heterogeneous response to a number of therapeutic regimens, as noted in other reports. Severe morbidity was present; three of our patients died, and one had leg amputation. "Residua" were, in fact, residual vascular neoplasia, variable in duration, and not a stable fibrofatty residuum, as in classic involuted hemangioma; only the hematologic phenomenon was "cured" after a period of years.

CONCLUSIONS

KMS is a distinctive disease of infancy, but the underlying vascular lesion is not a "true," classic, involuting type of hemangioma of infancy. This is a different vascular tumor with a resemblance pathologically to either tufted angioma or kaposiform hemangioendothelioma in association with lymphatic-like vessels. Whether the underlying lesion in KMS is a single anatomic entity or heterogeneous cannot be definitely concluded from this study. We need a better understanding of the pathogenesis of KMS to improve our therapeutic management.