Final Pr. ID: Poster #: EDU-022
Pancreatic tumours are a rare and unusual entity in pediatric patients accounting for less than 0.2% of malignant paediatric deaths. The limited number of cases and the diversity of histopathologic subtypes have made it difficult to predict prognosis which differs significantly from adults. In general, pancreatic tumours that occur in children are well circumscribed and partially encapsulated. Their relatively soft nature and encapsulated rather than infiltrative growth pattern allow them to become large prior to clinical presentation. Owing to their large size, central necrosis is common.
Causes of pancreatic masses in children are usually benign and include pancreatic pseudocyst, congenital pancreatic cyst, dermoid cyst, hydatid cyst, islet cell tumours, lymphangioma, pancreatic hemangioendothelioma and cystadenomas. Causes of malignant pancreatic masses in children (which are rare) include pancreatoblastoma, lymphoma, neuroblastoma, solid-pseudopapillary tumour and rhabdomyosarcoma.
We present an algorithmic approach to a pancreatic mass in a child, describing the common imaging features in each of the benign and malignant causes of pancreatic mass in a child with radiologic cases. We also report a very rare case of a pancreatic kaposiform hemangioendothelioma in an 8 month old boy who presented with Kasabach Merritt syndrome.
Authors: Mahomed Nasreen
Final Pr. ID: Poster #: CR-009
The aim of this report is to document the clinical presentation, multimodality imaging features, and management of patients with diffuse intra-abdominal Infantile Hemangioma (IH) and Kaposiform Hemangioendothelioma (KHE). Read More
Final Pr. ID: Poster #: CR-006
Kaposiform hemangioendotheliomas (KHE) are rare, locally aggressive vascular neoplasms. KHE most commonly arise from the extremities and less frequently the trunk and head and neck regions. Kasabach-Merritt phenomenon complicates 70% of cases. Three cases of KHE underwent prenatal evaluation and postnatal management at our center. We report the imaging findings that may allow for improved prenatal diagnosis.
Case 1: 31-year-old G4P2 evaluated for cervicofacial mass at 24 weeks 5 days. Fetal ultrasound demonstrated a large, infiltrative, predominately solid, mildly heterogeneous mass with a volume of 62 mL. No calcifications or lesion hypervascularity were present. Same day MRI confirmed an infiltrative, predominately solid mass with mild heterogenous T2 signal and no internal flow voids. Repeat MRI at 34 weeks 5 days revealed increased lesion heterogeneity and internal flow voids. US at 36 weeks 3 days demonstrated a volume of 525 mL and lesion hypervascularity. Delivery was at 36 weeks 5 days by EXIT procedure. Kasabach-Merritt phenomenon developed, and postnatal biopsy was consistent with KHE.
Case 2: 35-year-old G2P1 evaluated for cervical mass at 40 weeks 4 days. Fetal ultrasound demonstrated a large, infiltrative predominately solid, mildly heterogeneous mass with a volume of 180 mL. Calcifications and hypervascularity were present. Fetal MRI was not performed. Delivery the next day was by cesarean section. Kasabach-Merritt phenomenon developed. Postnatal biopsy was consistent with KHE.
Case 3: 30-year-old G1P0 evaluated for cervical mass at 38 weeks 1 day. Fetal ultrasound demonstrated a large, predominately solid, heterogeneous mass with a volume of 242 mL. Calcifications and hypervascularity were present. Same day fetal MRI confirmed an infiltrative, predominately solid mass with heterogeneous T2 signal and internal flow voids. Delivery was at 38 weeks 3 days by cesarean section. Kasabach-Merritt phenomenon developed, and postnatal MRI and clinical findings were consistent with KHE. Read More
Keywords: Kaposiform hemangioendothelioma, cervical masses
Final Pr. ID: Poster #: CR-034
Prenatal screening ultrasound at 18 weeks gestation identified homogeneous enlargement of the distal left leg. There was relative increased blood flow by Doppler, but the bone lengths were symmetric. There were no cysts and no amniotic bands. MRI was performed at 21 weeks gestation for further characterization. MRI demonstrated a lobulated, infiltrative, asymmetric soft tissue signal intensity thickening extending from the knee to the dorsum of the foot. There was no fat content appreciable on T1 or T2 fat saturated images. Given these findings, a vascular soft tissue mass such as kaposiform hemangioendothelioma was the primary differential consideration, with other fibrous tumors considered less likely. Follow up ultrasounds demonstrated commensurate growth of the lesion with the child.
At scheduled cesarean delivery, the otherwise healthy female infant had a leg mass that measured 14 cm, extending from the knee to the dorsum of the foot, as seen on prenatal imaging. The skin overlying the lesion was thick and redundant with hypertrichosis. Postnatal MRI was performed on day 2, unexpectedly showing extensive fat signal, along with edema signal and enhancement of the muscle, fat, and thickened skin. There was no abnormal vascularity and no focal mass. There was mild tibial bowing. Incisional biopsy was performed on day 6, with pathologic diagnosis of spindle cell tumor suggestive of fibrous hamartoma of infancy (FHI).
This apparent case of FHI is an atypical presentation, with interesting imaging implications. FHI is usually smaller (3-5 cm), more common in males (2.4:1), and only rarely involves the lower extremities distal to the knee (0.5% of cases). Only 23% of FHI are present at birth. To our knowledge, there are no case reports describing the fetal MRI appearance of this entity. Hamartomatous lesions and macrodystrophia lipomatosa had been excluded from the differential diagnosis due to the lack of fat signal intensity on fetal MRI. However, the fetus was imaged in early second trimester and normal subcutaneous fat is usually not visible on MRI until late in the second trimester. This case raises questions regarding the timing of appearance of fat in this lesion. As a result, we recommend that fat containing lesions not be excluded on the basis of absence of fat in early fetal MRI. Repeat MR imaging of musculoskeletal tumors in the third trimester to re-assess content may be useful. Read More