Multivisceral resection of primary multifocal retroperitoneal sarcomas: a retrospective study from a high-volume sarcoma center

BACKGROUND: Although surgery plays a key role in the treatment of the primary retroperitoneal sarcoma (RPS), there remain few reports on the primary multifocal RPS. AIMS: This study aimed to identify the prognostic factors for the primary multifocal RPS in an effort to optimize the clinical management of this malignancy. METHODS: A retrospective analysis was conducted on a cohort of 319 primary RPS patients who underwent radical resection from 2009 to 2021, with post-operative recurrence as the primary endpoint of this study. COX regression was performed to identify the risk factors for post-operative recurrence, and a comparison was made to baseline and prognostic differences between multivisceral resection (MVR) and non-MVR groups with multifocal disease. RESULTS: There were 31 (9.7%) patients with multifocal disease, the mean tumor burden placed on them was 24.1 ± 11.9 cm, and nearly half of the patients (48.4%) had MVR. Dedifferentiated liposarcoma, well-differentiated liposarcoma, and leiomyosarcoma accounted for 38.7%, 32.3%, and 16.1%, respectively. The 5-year recurrence-free survival rate reached 31.2% (95% CI, 11.2–51.2%) in the multifocal group and 51.8% (95% CI, 44.2–59.4%) in the unifocal group (P = 0.010). Age (heart rate [HR] = 0.916; P = 0.039) and complete resection (HR = 1.861; P = 0.043) were identified as the independent risk factors for the post-operative recurrence of multifocal primary RPS. CONCLUSIONS: Regarding primary multifocal RPS, the overall treatment strategy can be adopted for the treatment of the primary RPS, and MVR remains effective in boosting the chance of disease control for a selected group of patients. RELEVANCE FOR PATIENTS: This study is relevant to patients as it highlights the importance of receiving appropriate treatment for the primary RPS, especially for those with multifocal disease. The treatment options should be evaluated carefully to ensure that the patients receive the most effective treatment for their specific type and stage of RPS. The potential risk factors for post-operative recurrence should be well understood to minimize those risks. Ultimately, this study underscores the importance of ongoing research to optimize the clinical management of RPS and improve outcomes for patients.