Case Presentation: A 36 year-old otherwise healthy female presented with six days of acute flu-like symptoms, myalgias, persistent fever and chills associated with abdominal bloating and vomiting for three days. Physical exam was notable for temperature of 103 F, sinus tachycardia and mild tenderness at the left upper quadrant on deep palpation. Labs were notable for a normal WBC count, mildly elevated alkaline phosphatase and total bilirubin. The flu swab was negative. The Chest CT showed confluent 9 x 5 cm anterior mediastinal and 2 x 2 cm sub carinal lymphadenopathy extending to the aortopulmonary window. On abdominal CT abdomen and pelvis there is marked diffuse,bulky and confluent upper abdominal, mesenteric and retroperitoneal adenopathy. The patient underwent mediastinal video assisted thoracoscopic surgery (VATS) which showed papillary intralymphatic angioendothelioma (PILA). The patient was referred to a vascular anomalies’ specialist and was prescribed Sirolimus for prophylaxis immunosuppressant therapy.

Discussion: Fever, myalgia, chills and diffuse lymphadenopathy are often encountered by the General Internist. While the most concerning diagnosis is lymphoma, papillary intralymphatic angioendothelioma (PILA), also referred to as Dabska tumor, is a very rare locally invasive, neoplasm of lymphatic vascular origin. It commonly presents as a slowly growing, asymptomatic (without B symptoms), violaceous patch or nodule, arising from a pre‐existing lymphatic or vascular anomaly that typically occurs in children and young adults. However, PILA may also affect the elderly. It primarily affects the dermis and superficial soft tissue of the head and neck, trunk or extremities, but can also arise from deeper locations including spleen, bone and testis. In our case the lack of palpable nodule or subcutaneous lesions and the presence of typical B symptoms favored alternative differential diagnoses. Ultimately, the diagnosis was made microscopically and immunohistochemically.

Conclusions: Presently, there are diagnostic challenges for pathologists and providers given PILA’s rarity and histological complexity to distinguish between it from other vascular lesions and lymphoma. We present a new and unusual case of PILA presenting with typical B symptoms and multifocal intra-abdominal lesions. To our knowledge, most case reports describe asymptomatic and external presentations. It is important to rely on final pathology prior to assuming lymphoma is the most likely diagnosis. In our case PILA presented more like lymphoma than in other similar case reports, and led to a premature diagnosis given to the patient.