Prognostic Factor Analysis and Nomogram Construction of Primary Retroperitoneal Liposarcoma: A Review of 10 Years of Treatment Experience in a Single Asian Cohort of 211 Cases

ObjectiveThis study intended to retrospectively analyze the data of patients with primary retroperitoneal liposarcoma in a single Asian large-volume sarcoma center and to establish nomograms focused on PRLPS for predicting progression-free survival (PFS) and overall survival (OS).MethodsA total of 211 patients treated surgically for primary, non-metastatic retroperitoneal liposarcoma during 2009–2021 were identified, and clinicopathologic variables were analyzed. PFS and OS nomograms were built based on variables selected by multivariable analysis. The discriminative and predictive ability of the nomogram was assessed by concordance index and calibration curve.ResultsThe median follow-up time was 25 months. A total of 117 (56%) were well-differentiated, 78 (37%) were dedifferentiated, 13 (6%) were myxoid, and 3 (1%) were pleomorphic morphology. Compared to the western population cohort reported by the Memorial Sloan-Kettering Cancer Center, the median age of patients in this cohort was younger (57 vs. 63 years), the tumor burden was lower (20 vs. 26 cm), and the proportion of patients with R0 or R1 resection was higher (97% vs. 81%). The 5-year PFS rate was 49%, and factors independently associated with PFS were symptoms at visit, preoperative needle biopsy, histologic subtypes, and postoperative hospital stay. The 5-year OS rate was 72%. American Society of Anesthesiologists Physical Status and Clavien-Dindo classification were independently associated with OS. The concordance indexes for PFS and OS nomograms were 0.702 and 0.757, respectively. The calibration plots were excellent.ConclusionsThe proposed nomogram provided a favorable reference for the treatment of primary retroperitoneal liposarcoma patients.

Clinical Features and Prognostic Factors of Elderly Individuals with Retroperitoneal Liposarcoma

Background: This study attempted to evaluate the clinical features and prognostic factors of elderly patients with retroperitoneal liposarcoma (RLS) and establish a nomogram to predict overall survival (OS). Methods: Patients diagnosed with RLS from 2010 to 2015 were identified from the Surveillance Epidemiology and End Results database. Clinical features and prognostic factors were examined, and a nomogram was constructed. Results: There were many differences between the elderly patients with RLS and the young patients with RLS; these differences included marital status, surgery, radiation, chemotherapy, and OS (P<0.05). An analysis of prognostic factors showed that surgery, as the main treatment for elderly patients, can significantly improve prognosis. Histological type and AJCC stage also had a significant effect on OS. Unlike the young group, age was an independent prognostic factor for the elderly. Nomograms for the elderly population were developed based on these prognostic factors. The C-indexes of the 1-, 3- and 5-year survival nomograms were 0.737 (95% CI 0.692-0.782), 0.737 (0.692-0.782) and 0.7367 (0.692-0.782), and the AUCs at 1, 3, and 5 years were 0.749, 0.804 and 0.810, respectively. Further results demonstrate the superiority of this approach in risk stratification over the AJCC staging system. Conclusions: Elderly patients with RLS are a particular group of individuals who are distinct from young patients in many clinical characteristics, and the constructed nomograms could accurately predict OS in elderly patients with RLS.

Retroperitoneal Liposarcoma Presenting as Bilateral Inguinal Hernias

Liposarcoma is one of the most common soft tissue sarcomas and has multiple subtypes, including atypical, well-differentiated, and dedifferentiated liposarcoma1. These tumors most commonly occur in the extremities and the retroperitoneum2, and account for 20% of all retroperitoneal tumors3. Retroperitoneal liposarcoma is very rare overall, occurring in 2.5 per one million people4. Patients will present from symptoms of mass effect due to the uncontrolled growth in the large potential space of the retroperitoneum, with its median size being around 30 cm5. The mainstay of treatment for this type of tumor is resection to a negative margin6. This is a case report describing a retroperitoneal liposarcoma presenting with bilateral inguinal hernias containing intraperitoneal fat from mass effect.

Primary retroperitoneal liposarcoma: a rare case report

Primary retroperitoneal liposarcoma (PRPLS) is a rare malignant tumor with a low incidence. A 34-year-old female patient presented to our department with abdominal pain, nausea, and vomiting for 2 days. Abdominal computed tomography (CT) indicated a huge mass between the liver and kidney, with a clear boundary and measuring approximately 202 mm × 155 mm ×106 mm. The mass was considered a retroperitoneal lipoma or liposarcoma. The entire tumor was completely resected without auxiliary injury, and histopathology of the resected specimen indicated liposarcoma. The patient recovered well and was discharged from our department on the 6th postoperative day. No signs of relapse were seen during 1-year of follow-up. PRPLS is rare and without obvious symptoms in the early stage. CT plays a vital role in the diagnosis of PRPLS, and surgical resection is considered the most suitable treatment. Radiotherapy and chemotherapy might also be treatment options to improve the overall survival of PRPLS patients.