Via Research Recognition Day Program VCOM-Carolinas 2025

Case Reports

Recurrent Giant Retroperitoneal Dedifferentiated Liposarcoma Requiring Multiorgan Resection: a case report Cesar Prugue, OMS III 1 , Camden Pereira, OMS III 1 , Emma Bao, BS 2 , Bing Yi, MD 3 1. Edward Via College of Osteopathic Medicine, 350 Howard St, Spartanburg, 29303, SC 2. Duke University, Durham, 27708, NC 3. Surgery, Bon Secours St Francis, 1 St Francis Dr., Greenville, 29601, SC

Abstract

Case Presentation

Discussion

Conclusions ● DDL is highly aggressive, with rapid recurrence despite surgery and chemotherapy, highlighting the need for improved treatment strategies. ● Multiorgan resection may be necessary for high grade tumors, but the disease often recurs even after R0 resection. ● Further research into targeted therapies and improved surveillance methods is essential to better manage DDL and improve patient outcomes. and organ dysfunction. Ongoing trials (STRASS-2, TRASTS) are investigating new treatments, including neoadjuvant chemotherapy and radiotherapy, to improve outcomes. ● DDL has a high recurrence rate, often requiring multiple surgeries. Chemotherapy (AIM regimen) shows limited efficacy in controlling disease progression. ● Close surveillance, with imaging every 3-6 months for the first 2-3 years, is essential for early detection of recurrence. ctDNA is a potential alternative to imaging for monitoring. ● Extensive resections carry risks like bleeding, infection,

Patient Overview : ● 57-year-old male with no significant medical history, aside from appendectomy and hernia repair. Current smoker (8 – 9 cigarettes/day for 45 years). ● Presented with two-month history of intermittent fevers, nonproductive cough, and lower abdominal discomfort. Imaging and Diagnosis: ● December 2023: CT revealed a 12 x 12 x 16 cm retroperitoneal mass adjacent to the left kidney. Biopsy confirmed high-grade dedifferentiated liposarcoma. ● Surgical resection performed in December 2023. Postoperative recovery was uneventful, with resolution of fevers. Tumor Recurrence and Chemotherapy : ● April 2024: Follow-up imaging showed multiple soft tissue nodules surrounding the left kidney and spleen (largest 4.7 x 2.4 x 5.6 cm). Chemotherapy was initiated, but tumor continued to progress. ● July 2024: CT revealed a 15 x 14 x 21 cm multiloculated cystic mass and a 12 x 6 x 15 cm mass extending from the left kidney into the pelvis (Figure 1).

Introduction Dedifferentiated liposarcoma (DDL) is a rare, aggressive subtype of liposarcoma with a high recurrence rate and local invasiveness. A 57-year old male with a history of high-grade retroperitoneal DDL underwent initial resection in December 2023. Despite adjuvant chemotherapy, imaging in July 2024 showed tumor recurrence. This prompted a second surgery in August 2024, which involved nephrectomy, splenectomy, hemicolectomy, and distal pancreatectomy due to extensive local invasion. This case highlights the aggressive nature of high-grade DDL and its resistance to chemotherapy. Multiorgan involvement highlights the complexity of treatment, emphasizing the need for better therapies and effective surveillance. ● Liposarcomas are the most common soft tissue sarcoma but are still considered rare cancers. ● Dedifferentiated liposarcoma (DDL) is a high-grade malignant subtype found primarily in the retroperitoneum with a high recurrence rate (40%) and metastasis (15-30%). ● Surgical resection is the primary treatment for retroperitoneal liposarcomas, with radiation and chemotherapy showing limited efficacy. ● Neoadjuvant chemotherapy and targeted molecular therapies are being explored to improve outcomes in high-grade liposarcoma. ● This case demonstrates the complexity of multiorgan resection required due to extensive

Figure 1: Coronal view of the abdomen with masses extending from the spleen to the pelvis

Surgical Intervention: ● August 2024: Second surgery required nephrectomy, splenectomy, hemicolectomy, distal pancreatectomy, and small bowel resection due to extensive tumor invasion (Figure 2). Pathology confirmed dedifferentiated liposarcoma (Figure 3).

References

1.Increasing incidence of liposarcoma: a population-based study of national surveillance databases, 2001-2016. Int J Environ Res Public Health 17(8), 2710 (2020) https://doi.org/10.3390/ ijerph17082710 2.The 2020 who classification of soft tissue tumours: news and perspectives. Pathologica 113(2), 70 – 84 (2021) https://doi. org/10.32074/1591-951X-213 3.Surgical management of retroperitoneal sarcoma. Curr Oncol 30(5), 4618 – 4631 (2023) https://doi.org/10.3390/curroncol30050349

Acknowledgements

Figure 3: Retroperitoneal mass having malignant spindle cells consistent with prior dedifferentiated liposarcoma

Figure 2: Resected tumor. Spleen (black arrow) and descending colon (green arrow)

We would like to thank the patient for allowing us to write and publish this case report.

tumor invasion, including nephrectomy, splenectomy, hemicolectomy, and distal pancreatectomy.

Postoperative Recovery: ● Patient progressed well after surgery, meeting discharge milestones. Currently under serial imaging follow-up due to high recurrence risk.

2025 Research Recognition Day

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