Paraneoplastic syndrome in undifferentiated embryonic sarcoma of the liver

Abstract

Background: The undifferentiated embryonic sarcoma of the liver (UESL) is a rare, aggressive tumor mainly affecting children. Since UESL has no specific clinical symptoms or imaging characteristics, many cases of UESL are diagnosed late. The paraneoplastic leukemoid reaction (PLR) is a very rare concomitant of oncological patients associated with poor prognosis. This report describes the clinical course of a patient combining these two rare entities and describes the diagnostic challenges and dynamics of paraneoplastic syndrome.

Case presentation: We report a case of UESL in a 46-year-old male who became clinically conspicuous due to pronounced B symptoms. CT and MRI showed a suspicious unifocal liver lesion. As the histological analysis of a tissue sample did not reveal a clear result, an 18F-FDG-PET-CT examination was performed. In addition to a high glucose metabolism of the liver lesion, an increased glucose metabolism in the entire bone marrow was observed. This finding was considered as pronounced paraneoplasia and laparotomy with liver segment resection followed. Immediately after resection of the tumor the paraneoplastic symptoms completely declined and the patient showed no signs of recurrence in the 1-year follow-up.

Conclusions: Although UESL is rare and predominantly affects children, this diagnosis should always be considered for unclear unifocal cystic liver lesions, regardless of the patient's age, as appropriate treatment has a good prognosis.

Keywords: PET-CT; PET-MRI; Paraneoplastic leukemoid reaction (PLR); Paraneoplastic syndrome (PNS); Undifferentiated embryonic sarcoma of the liver (UESL).

Fig. 1

The initial CT abdomen during the portal venous phase in axial reconstruction (upper left) shows a hypodense lesion (*) in liver segment VII. In the MRI examination, the lesion had hypointense signal in the T1 vibe Dixon sequence (lower row on the left) and a hyperintensive signal in the T2 blade fs (bottom row on the right)

Fig. 2

[¹⁸F] FDG whole-body PET-CT examination shows the known unifocal hypodense liver lesion and a distinct tracer uptake (SUV peak 33) without evidence of further suspicious lesions. Additionally, an increased signal in the entire bone marrow was found

Fig. 3

The inpatient admission of the patient was at a CRP of 14.75 mg/dl and increased leukocytes (45,560/μl). The CRP increased to a maximum of 20.97 mg/dl preoperatively, and the leukocytes reached their peak on the day of surgery with a value of 100,370/μl. Immediately postoperative both inflammatory values dropped sharply and leucocytes reached their normal values on the third postoperative day (8770/μl) and CRP on the 12th postoperative day (0.43 mg/dl)

Fig. 4

FDG PET tracer uptake before (upper row) and after (lower row) surgery: after resection of the tumor FDG PET showed complete normalization of bone marrow metabolism