Significant Predictors of Postoperative Morbidity After Radical Resection of Retroperitoneal Sarcoma in a Tertiary Center.

BACKGROUND: The safety of multivisceral resection of retroperitoneal sarcoma is an issue. Previous reports have investigated its associations with the pattern of resection and factors recognized mostly per operatively. METHODS: All consecutive RPS resections from May 2015 to April 2022 were studied retrospectively with respect to adverse events. Two univariate and multivariate logistic regression analyses were performed to investigate the associations between severe adverse events and factors recognized pre- and per operatively. Associations of adverse events with overall survival (OS) and local recurrence (LR) were investigated. RESULTS: A total of 265 surgical interventions corresponding to 251 patients were recorded (38 RPS surgeries/year). Severe postoperative adverse events (Clavien-Dindo ≥ 3) occurred in 50 patients (18.9%), 15 (5.6%) patients underwent an iterative laparotomy, and 6 patients (2.3%) died within 90 days. On multivariate analysis including all parameters known preoperatively, male sex, performance status, dedifferentiated liposarcoma histology, and low serum albumin level were found to be significant predictors of major complications, whereas the timing of surgery and preoperative treatment were not. On univariate analysis including all per operative parameters, transfusion requirement, operative time, number of digestive anastomoses, and pancreas and/or major arterial resection were found to entail higher operative risk. On multivariate analysis, only transfusion requirement was significant. There was no impact of postoperative adverse events on OS or LR. CONCLUSIONS: The recognition of preoperative parameters that impact safety could mitigate the extent of the surgery, specifically the resection of adherent organs not overtly invaded. For the best decision, this surgery should be performed in referral centers.

Arterial Reconstruction for En-Bloc Resection of Soft Tissue Sarcoma: A Single Tertiary Center Experience.

BACKGROUND: Tertiary centers recruit a number of locally advanced or recurrent soft tissue sarcomas (STSs) that require large tissue loss including vessels. Arterial reconstruction (AR) in the context of patients with cancer who may receive radiotherapy (RT) and chemotherapy (CT) is challenging. METHODS: This retrospective single centre cohort study includes patients affected by extremities or trunk STS who underwent an AR during sarcoma resection, between October 2015 and February 2021 at Institut Curie. The endpoints of this study were to analyze the morbidity, the patency, and the impact on surgical margins of such associations. RESULTS: Of 976 patients operated, 21 (2.15%) had AR. Seventeen (81%) had American Society of Anesthesiologists (ASA) scores ≥2. Locations were as follows: intra-abdominal n = 9 (43%), lower limb n = 8 (38%), upper limb n = 3 (14%), and cervical n = 1 (5%). N = 11 (52.3%) and n = 5 (23.8%) received RT or were operated on a preirradiated field, respectively. N = 7 (34%) patients received CT. Vein graft was used in n = 12 (57%). Musculo-cutaneous flaps were associated in n = 13 (62%) patients. Margins of resection were R0 n = 19 (90.4%), R1 n = 2, and R2 n = 0. The median follow-up was 16 months [6-44]. No postoperative death occurred. Two patients died of metastasis. At 1, 6, 12, and 24 months the primary patency was 80.9%, 71.4%, 87.5%, and 88.9%, respectively. Seven patients (33%) presented perioperative infection. Reoperation rate at 1, 6, and 12 months were 38%, 14%, and 5%, respectively. Ten patients (48%) presented persistent lymphoedema during follow-up. CONCLUSIONS: AR enlarges the possibilities of STS excision with healthy margins and achieves good patency. Majority of patients were ASA ≥ 2 and received adjuvant treatments. In this particular context, morbidity is high and requires an upfront multidisciplinary management taking into account all these specific issues.

Tumor Growth Rate as a Predictive Marker for Recurrence and Survival After Liver Resection in Patients with Liver Metastases of Uveal Melanoma.

BACKGROUND: Surgical management of liver metastases of uveal melanoma (LMUM) is associated with the best survival rates, especially for patients with a low tumor burden in the liver. The aim was to determine whether the tumor growth rate (TGR0) before liver resection helps predict survival in patients with resectable LMUM. METHODS: This retrospective study included 99 patients with LMUM treated with liver resection between November 2007 and November 2020. TGR0 was expressed as the percentage change in tumor volume over 1 month according to two pretreatment imaging scans. Multivariate Cox analyses identified independent predictors of disease-free survival (DFS) and overall survival (OS). RESULTS: DFS and OS had a statistically significant positive linear relationship (Spearman correlation r = 0.68, p < 0.001). A disease-free interval (DFI) > 24 months and a TGR0 ≤ 50%/month were independent factors associated with better DFS and OS. The 2-component model including TGR0 and DFI had a mean time-dependent area under the curve (AUC) of 0.81 (95% CI, 0.75-0.86) and 0.77 (95% CI, 0.67-0.87), respectively, for predicting DFS and OS. DFI with TGR0 defined three kinetic risk groups that had distinct DFS and OS outcomes (p < 0.001). Cytogenetic alterations at baseline were partially predictive factors of the kinetic risk score based on TGR0 and DFI. DISCUSSION: The assessment of TGR0 improves prognostic stratification by identifying patients at high risk of recurrence and poor survival after liver resection. TGR0 and DFI, reflecting tumor aggressivity, have the potential to be important markers for systemic adjuvant decisions.

Management of Locally Recurrent Retroperitoneal Sarcoma in the Adult: An Updated Consensus Approach from the Transatlantic Australasian Retroperitoneal Sarcoma Working Group.

BACKGROUND: Surgery is the mainstay of treatment for retroperitoneal sarcoma (RPS), but local recurrence is common. Biologic behavior and recurrence patterns differ significantly among histologic types of RPS, with implications for management. The Transatlantic Australasian RPS Working Group (TARPSWG) published a consensus approach to primary RPS, and to complement this, one for recurrent RPS in 2016. Since then, additional studies have been published, and collaborative discussion is ongoing to address the clinical challenges of local recurrence in RPS. METHODS: An extensive literature search was performed, and the previous consensus statements for recurrent RPS were updated after review by TARPSWG members. The search included the most common RPS histologic types: liposarcoma, leiomyosarcoma, solitary fibrous tumor, undifferentiated pleomorphic sarcoma, and malignant peripheral nerve sheath tumor. RESULTS: Recurrent RPS management was evaluated from diagnosis to follow-up evaluation. For appropriately selected patients, resection is safe. Nomograms currently are available to help predict outcome after resection. These and other new findings have been combined with expert recommendations to provide 36 statements, each of which is attributed a level of evidence and grade of recommendation. In this updated document, more emphasis is placed on histologic type and clarification of the intent for surgical treatment, either curative or palliative. Overall, the fundamental tenet of optimal care for patients with recurrent RPS remains individualized treatment after multidisciplinary discussion by an experienced team with expertise in RPS. CONCLUSIONS: Updated consensus recommendations are provided to help guide decision-making for treatment of locally recurrent RPS and better selection of patients who would potentially benefit from surgery.

Management of Primary Retroperitoneal Sarcoma (RPS) in the Adult: An Updated Consensus Approach from the Transatlantic Australasian RPS Working Group.

BACKGROUND: Retroperitoneal soft tissue sarcomas comprise a heterogeneous group of rare tumors of mesenchymal origin that include several well-defined histologic subtypes. In 2015, the Transatlantic Australasian RPS Working Group (TARPSWG) published consensus recommendations for the best management of primary retroperitoneal sarcoma (RPS). Since then, through international collaboration, new evidence and knowledge have been generated, creating the need for an updated consensus document. METHODS: The primary aim of this study was to critically evaluate the current evidence and develop an up-to-date consensus document on the approach to these difficult tumors. The resulting document applies to primary RPS that is non-visceral in origin, with exclusion criteria as previously described. The relevant literature was evaluated and an international group of experts consulted to formulate consensus statements regarding the best management of primary RPS. A level of evidence and grade of recommendation were attributed to each new/updated recommendation. RESULTS: Management of primary RPS was considered from diagnosis to follow-up. This rare and complex malignancy is best managed by an experienced multidisciplinary team in a specialized referral center. The best chance of cure is at the time of primary presentation, and an individualized management plan should be made based on the 29 consensus statements included in this article, which were agreed upon by all of the authors. Whenever possible, patients should be enrolled in prospective trials and studies. CONCLUSIONS: Ongoing international collaboration is critical to expand upon current knowledge and further improve outcomes of patients with RPS. In addition, prospective data collection and participation in multi-institution trials are strongly encouraged.

Simultaneous combined anterior and posterior approach for en bloc resection of sciatic notch sarcomas.

BACKGROUND: Monobloc resection of soft tissue sarcomas (STSs) has a major impact on overall survival and local recurrence. Anatomical boundaries, such as the sciatic notch, increase the risk of fragmentation of the lesion. To date there are few papers describing the optimal surgical technique to remove such STSs. The objective of this study is to describe a simultaneous anterior and posterior approach for resection of sciatic notch dumbbell tumours. CASE PRESENTATION: We present the surgical management of two patients diagnosed with well-differentiated liposarcomas of the sciatic notch with a retroperitoneal and gluteal extension in the two cases. Pre-operative diagnosis was made with a percutaneous biopsy including molecular analysis which demonstrated MDM2 amplification. We describe a simultaneous anterior and posterior approach, including the ligation of the posterior trunk of the internal iliac artery, to reduce intra-operative blood loss and devascularise the tumour. The anterior approach allows the evaluation of the tumour's retroperitoneal extension, release from its pelvic attachments and control of the surrounding neurovascular structures. During the posterior approach, bleeding is reduced by the devascularisation of the gluteal musculature achieved with internal iliac artery ligation. Clear margins were achieved in both cases. No vascular, skeletal or soft tissue reconstructions were required. CONCLUSIONS: Simultaneous combined anterior and posterior approaches to remove a malignant sciatic notch tumour optimises the chance of complete en bloc resection. This surgical strategy allows oncologic en bloc resection with minimal blood loss.

Major vascular resections in retroperitoneal sarcoma.

Retroperitoneal sarcomas (RPS) frequently involve major vessels, which either originate from them or secondarily encase or invade them. In this field, major vascular resections result in increased morbidity. However, survival does not seem to be affected by the need for vascular resection or by this higher morbidity. This paper aims to provide descriptions of the surgical strategy and outcomes for retroperitoneal sarcomas involving major vessels.

Diagnostic accuracy and safety of percutaneous core needle biopsy of retroperitoneal tumours.

BACKGROUND: Histologic subtype of cancer guides treatment sequencing and the extent of surgery for retroperitoneal tumours (RPTs) but concerns persist regarding percutaneous core needle biopsy (CNB). OBJECTIVE: Endpoints were the incidence of early complications, needle tract seeding (NTS) after CNB, diagnostic accuracy. METHODS: Between 2015 and 2022, data from patients with RPT who underwent a CNB and who operated on at Institut Curie were collected. We retrospectively reviewed the medical records and microscopic analysis of both CNB and surgical specimens to evaluate the diagnostic accuracy of CNB (quantified using positive and negative predictive values, PPV/NPV). RESULTS: 313 patients underwent CNB. In 10/326 (3 %) procedures, minor complications were observed. One of 212 (0.47 %) resected RPSs exhibited a local recurrence compatible with NTS. Microscopic analysis of CNB specimens allowed the classification of tumours between groups of cancers and benign/intermediate mesenchymal tumours in 307/313 (98 %) patients. Among the 204 patients with retroperitoneal sarcoma, the overall concordance between CNB and final pathology following resection was 178/204 (87.2 %). The respective PPVs of solitary fibrous tumour, dedifferentiated liposarcoma, leiomyosarcoma and well-differentiated liposarcoma were 100 %, 98 %, 97 % and 68 %, respectively. The diagnosis of a high-grade (G 2-3) sarcoma resulted in a high specificity (97 %) and PPV (98 %) but low sensitivity (76 %). CONCLUSIONS: CNB allowed the classification of RPT in the vast majority of patients with a low morbidity rate. Concordance with final diagnosis was high for sarcomas with the exception of well-differentiated liposarcoma. As a result, CNB results should be integrated with imaging/radiomics by multidisciplinary tumour boards.

Two Different Types of Sarcoma Occurring Synchronously: The Impact of Molecular Biology on Therapeutic Strategy.

Sarcoma is a rare type of tumor that can arise in the different types of connective tissues. Symptoms vary depending on the size, type, and location of the tumor. Management and surgery should be performed in a referral sarcoma center with a molecular biology platform and a dedicated medical staff. A preoperative percutaneous core needle biopsy (CNB) is required to tailor the medical and surgical strategies. In this report, we describe the case of a well-differentiated retroperitoneal liposarcoma (WD LPS) discovered in the context of recurrent cystitis on an abdominal CT scan, synchronously occurring, with another different type of sarcoma, undifferentiated pleomorphic sarcoma (UPS) developing in the thigh, discovered because of sciatic pain. This extremely rare condition was confirmed by the molecular analysis and justifies a specific strategy taking account of the differential risk. This event should also encourage genetic counseling.