Background: The clinical outcome of inoperable sarcoma patients treated with LATTICE (LRT) is limited and therefore the objective of our study was to report treatment response, overall survival (OS), local-recurrence free survival (LRFS) and toxicity. Methods: This retrospective observational study includes 15 histologically proven inoperable non-extremity sarcoma patients with no treatment options or no response to systemic therapy, treated at our institution between 2020 and 2024. The patients were treated with a combination of LRT and normo- or hypo-fractionated external beam radiotherapy. Treatment response was evaluated by RECIST1.1 criteria, toxicity by CTCAE 5.0 and OS and LRFS by Kaplan–Meier curves. Results: The median follow-up (F-UP) since the beginning of the treatment was 10 months (range 4–32). Nine patients were male and six female. Their mean age was 60 years. The median gross tumor volume (GTV) was 1058 cm³ (range 142–6103 cm³). The median number of spheres was 9 (4–30). All patients with symptoms reported symptoms’ relief. Based on RECIST1.1 criteria, 10 patients (67%) had stable local disease at 1–2 months F-UP on computed tomography (CT). Surgical resection was feasible in five patients. Three of them are alive without disease and two died due to metastatic progression. From 10 (67%) non operated patients, 5 patients died (50%) due to disease. The remaining five patients (50%) are alive, three with stable disease at 21, 22, and 32 months of F-UP and two with disease progression who are currently receiving palliative chemotherapy treatment. Reported G2 toxicity was as follows: gastrointestinal (2), asthenia (1). Two patients had G3 toxicity: esophagitis (1) and inguinal dermatitis (1). No acute or chronic G4–G5 toxicity was observed. Conclusions: LRT is a feasible and well-tolerated radiation technique for inoperable bulky soft-tissue sarcomas. Further studies are needed to establish protocols to determine which patients could benefit from palliative or preoperative treatment.

Soft tissue sarcomas (STS) are an uncommon and biologically heterogeneous group of tumors arising from mesenchymal cells. The incidence is estimated at five cases per 100,000 people per year. Retroperitoneal sarcomas (RPS) account for 10–15% of all STS, and their management depends on their anatomical characteristics and histotype. Due to their very low incidence, it is recommended that RPS be treated in reference centers and evaluated by an experienced multidisciplinary team (MDT). In Spain, the Spanish Group for Research in Sarcomas (GEIS) brings together experts from various specialties to promote research on sarcomas and improve treatment results. This paper summarizes the GEIS recommendations for the diagnosis, treatment, and follow-up of patients with RPS.

Peritoneal sarcomatosis is a rare malignant disease with a poor prognosis, secondary to peritoneal dissemination of abdominopelvic soft tissue sarcomas. Its rarity, together with the characteristic histological heterogeneity and the historically poor response to systemic treatments, has prevented the establishment of widely accepted treatment criteria with curative intent. In this sense, radical cytoreductive surgery (CRS) with peritonectomy procedures and hyperthermic intraperitoneal chemotherapy (HIPEC), widely used in peritoneal carcinomatosis with excellent results, have not had the same evolutionary development in patients with peritoneal sarcomatosis. A multidisciplinary working group of experts in sarcomas and peritoneal oncological surgery established a series of recommendations based on current scientific evidence for the management of peritoneal sarcomatosis, taking into account the different histological subgroups of abdominopelvic sarcomas that can cause it depending on their origin: retroperitoneal sarcomas, uterine sarcomas, and visceral/peritoneal sarcomas of GIST (gastrointestinal stromal tumor) and non-GIST origin. This article shows the results of sarcoma experts’ voting on the recommendations presented during the I Ibero-American Consensus on the Management of Peritoneal Sarcomatosis, which took place during the recent celebration of the III Hispanic-Portuguese Meeting for Updates on the Treatment of Sarcomas.

Liver metastases from soft tissue sarcoma (STS) (excluding gastrointestinal stromal tumors) are rare and more commonly arise from retroperitoneal and intra-abdominal primary sites. Chemotherapy remains the mainstay of treatment for disseminated disease, but its effectiveness is limited and patients typically have a dismal prognosis with short survival. However, when metastases are confined to the liver (without pulmonary involvement), some patients may benefit from local techniques, either surgical or nonsurgical, that can provide long periods of disease-free survival. Due to the rarity of STS, especially with liver metastases, and the heterogeneity of histologies and biological behavior, there is a lack of standardized treatment guidelines and universally accepted criteria for this specific setting. To fill this gap, a multidisciplinary working group of experts in sarcoma and liver surgery reviewed the literature and available evidence and developed a set of clinical recommendations to be voted and discussed in the I Ibero-American Consensus on the Management of Metastatic Sarcoma, held at the III Spanish-Portuguese Update Meeting on the Treatment of Sarcomas in May 2024. Herein, the voting results of this meeting and the resulting consensus recommendations are presented, and their applicability, strengths, and limitations are discussed.

With negligible risk of distant metastasis, the primary treatment focus in patients with primary retroperitoneal well-differentiated liposarcoma (pRP-WDLPS) is local control. The recently completed phase 3 STRASS trial suggested a potential benefit to neoadjuvant radiotherapy (RT) in optimizing local control in these patients. This study investigates outcomes associated with neoadjuvant RT in a larger cohort of patients undergoing surgery for pRP-WDLPS. In this study from 24 participating sites, we retrospectively identified all patients with pRP-WDLPS who underwent curative-intent resection between January 1, 2002 and December 31, 2017. The primary endpoint was the cumulative incidence function (CIF) of local recurrence (LR), and the secondary endpoint was overall survival (OS). The impact of neoadjuvant RT on the CIF of LR was analyzed using a 1:2 propensity score matching (PSM). Of 582 patients included in the entire cohort, 72 patients (12%) received neoadjuvant RT. The 1:2 PSM group included 208 patients of which 138 patients (66%) underwent surgery alone and 70 patients (34%) underwent neoadjuvant RT and surgery. With a median follow up of 73 months, the 5- and 8-year CIF of LR for neoadjuvant RT and surgery group was 6% and 10%, respectively, and 26% and 33%, respectively, for the surgery alone group (odds ratio (OR) 0·85, 95% confidence interval (CI) 0·76–0·97, P < 0·001). The 5- and 10-year OS for the neoadjuvant RT and surgery group was 92% and 80%, respectively, and 84% and 71%, respectively, for the surgery alone group (HR 0·50, 95% CI 0·27–1·21, P = 0·07). To the best of our knowledge, this is the largest study to report outcomes of neoadjuvant RT for pRP-WDLPS. Neoadjuvant RT was associated with a significant decrease in LR compared to surgery alone. These data further validate the use of neoadjuvant RT for pRP-WDLPS. Funding was received from the Susan and Habib Gorgi Family Fund for Sarcoma Research.