case_images: PMC10191730_01
case_images: (
  A
  ) Vascular anomaly with subcutaneous cervical component and thoracic extension with slight violaceous skin coloration and minimal superficial component (arrows). (
  B
  ) Circumferential pericardial effusion of 36 mm with mild diastolic restriction, collapse of right cavities, and echographic signs of cardiac tamponade (*).
case_images: 10-1055-a-2057-7177-i2022050663cr-1.jpg
case_images: PMC10191730_01_10-1055-a-2057-7177-i2022050663cr-1.jpg
case_images: FI2022050663cr-1
case_images: On examination, there was a subcutaneous, violaceous, and irregular lesion on the neck and upper thorax with slight superficial component ( Fig. 1A ), associated with intermittent pain and distant heart sounds; thus, an echocardiogram was performed that confirmed severe pericardial effusion impairing cardiac dynamics ( Fig. 1B ). 
case_images: (
  A
  ) Diffuse vascular proliferation in the cervical region (white arrow) with thoracic and mediastinal extension (yellow arrow). (
  B
  ) Hematoxylin and eosin stain x3 magnification showing on one side lobules of hypercellularity and predominance of capillaries (oval), and on the other side proliferation of dilated and large vessels in lower dermis and hypodermis with scarce cellularity (arrow). Histologic findings were compatible with characteristics of vascular tumor and, at the same time, of vascular malformation. (
  C
  ) Appearance of pericardial effusion fluid.
case_images: 10-1055-a-2057-7177-i2022050663cr-2.jpg
case_images: PMC10191730_01_10-1055-a-2057-7177-i2022050663cr-2.jpg
case_images: FI2022050663cr-2
case_images:  Subsequently, an MRI was performed that visualized a diffuse vascular lesion in the subcutaneous tissues of the cervical and upper thoracic region, with extension to the anterior mediastinum in the upper two-thirds of the retrosternal area and surrounding the outlet of the great vessels ( Fig. 2A ). Sample also presented different degrees of cellularity suggesting a tumor etiology, but on the other hand, an important vascular component pointing to a vascular malformation ( Fig. 2B ), so a diagnosis by exclusion of PUVA was established.  Then, a pericardial drain was placed evacuating 280 mL of lymphoid fluid with a pH 7.4, protein 1 g/dL, lactate dehydrogenase 80 IU/L, cholesterol 26 mg/dL, triglycerides 31 mg/dL, and leukocytes 200/mm 3 without malignant cells, compatible with transudate ( Fig. 2C ).