2.1 Diagnosis
In the past, the term “hemangioma” was used to represent all benign vascular lesions regardless of etiology, disease course or pathology. Based on clinical characteristics, radiologic imaging and pathologic findings, the International Society for the Study of Vascular Anomalies (ISSVA) created a standardized classification system in 1996 which broadly categorized vascular anomalies as tumors and vascular malformations. The ISSVA classification system was most recently updated in 2018 and can be accessed atwww.issva.org/classification.
As we will illustrate in the following 3 cases, initial presentation of CLA is variable, and the provider needs to have a high index of suspicion for and familiarity with these conditions in order to provide timely diagnosis and appropriate management.
Radiologic evaluation should include imaging of the chest, abdomen, pelvis and total spine with CT and/or MRI. If suspicion for GSD, skull imaging is indicated. Skeletal bone survey may be used to focus imaging needs. MR lymphangiogram can also be helpful in certain situations [14].
Laboratory investigation should include complete blood count with differential, D-dimer, fibrinogen, prothrombin time (PT), partial thromboplastin time (PTT), albumin and total protein, immunoglobulins, liver and renal function tests, electrolytes and bone turn-over markers (alkaline phosphatase, C-telopeptide, etc.).
The extent and characteristics of the bony lesions, distribution of viscera involvement, laboratory findings generally will provide criteria for final diagnosis, frequently without a biopsy. In situations in which the diagnosis is unclear despite medical history, imaging and laboratory findings, biopsy of a soft tissue lesion is recommended over bone biopsy. Biopsy of ribs and vertebrae should be avoided as these can result in pleural effusions and CSF leaks [15, 16]. In patients with KLA, biopsy may result in significant bleeding and worsen the underlying coagulopathy. Because mutations in CLA are somatic, genetic testing of the affected tissue, not peripheral blood, should be considered to guide therapy.