Super-giant exophytic hepatocellular carcinoma mimicking retroperitoneal sarcoma: a case report
Kayahan Eyüboğlu, Bilal Alkaş, Hakan Küçükaslan, Adnan Gündoğdu, Ümit Çobanoğlu, Serdar TopaloğluIntroduction and importance:
Hepatocellular carcinoma (HCC) is the most common primary malignant liver tumor. Extrahepatic or exophytic growth is rare and diagnostically challenging because masses extending beyond the hepatic contour may mimic intra-abdominal or retroperitoneal tumors. This case is educational because a super-giant exophytic HCC initially resembled a retroperitoneal sarcoma but was successfully managed surgically despite an advanced anatomic stage.
Presentation of case:
An 81-year-old male patient without cirrhosis or viral hepatitis presented with right-sided abdominal swelling. Serum alpha-fetoprotein (AFP) was markedly elevated at 16 600 μg/L, and imaging showed a large mass compressing the right adrenal gland, right kidney, and inferior vena cava. The main differential diagnoses were exophytic HCC and retroperitoneal sarcoma. After multidisciplinary evaluation, the tumor was removed en bloc by segment V liver resection with omentectomy and concomitant cholecystectomy. Because of omental wrapping, the case was staged as pT4N0M0, stage IIIB. The postoperative course was uneventful; AFP normalized, and no recurrence or metastasis was detected at 7 months.
Clinical discussion:
Although advanced anatomical stage and very large tumor size are associated with an increased risk of recurrence, the absence of major vascular and lymphovascular invasion and the achievement of R0 resection were favorable factors that supported surgical treatment.
Conclusion:
This case highlights that exophytic HCC can mimic retroperitoneal sarcoma, AFP may provide an important diagnostic clue during preoperative assessment, and treatment decisions should be individualized. In selected patients with giant or super-giant exophytic HCC, surgical resection may provide satisfactory short-term oncologic outcomes when major vascular invasion is absent and a negative surgical margin can be achieved.