Soft-tissue sarcoma in adults: An update on the current state of histiotype-specific management in an era of personalized medicine.

Soft-tissue sarcomas (STS) are rare tumors that account for 1% of all adult malignancies, with over 100 different histologic subtypes occurring predominately in the trunk, extremity, and retroperitoneum. This low incidence is further complicated by their variable presentation, behavior, and long-term outcomes, which emphasize the importance of centralized care in specialized centers with a multidisciplinary team approach. In the last decade, there has been an effort to improve the quality of care for patients with STS based on anatomic site and histology, and multiple ongoing clinical trials are focusing on tailoring therapy to histologic subtype. This report summarizes the latest evidence guiding the histiotype-specific management of extremity/truncal and retroperitoneal STS with regard to surgery, radiation, and chemotherapy.

Current patterns of care and outcomes for dermatofibrosarcoma protuberans: An international multi-institutional collaborative.

BACKGROUND: Dermatofibrosarcoma protuberans (DFSP) is a cutaneous sarcoma with an infiltrative growth pattern that makes it challenging to clear margins. High quality data regarding DFSP natural history, management, and outcomes are limited. METHODS: Data were retrospectively collected for adult DFSP patients who underwent resection at 10 institutions in eight countries. Demographics, tumor characteristics, treatment strategies, and outcomes were analyzed. RESULTS: Analysis included 347 patients consisting of young (median, 42 years), White (76.2%), males (54.2%) with truncal lesions (57.3%). The majority (76.8%) were symptomatic at presentation. Preoperative imaging was used in 55.9% of cases. Diagnosis was established with excisional biopsy in 50.9% versus incisional biopsy in 25.0% of cases. Despite planned margins of >1.0 cm in 67.4% of cases, only 69.0% of patients achieved R0 resection. Twenty-two percent of patients underwent at least one re-excision. R0 resection was achieved at a second procedure in 80.2% and a third procedure in 86.2%. Ultimately, R0 resection was feasible in 89.5% of all patients. Fibrosarcomatous transformation (FST) was observed in 12.6%. In total, 6.6% (N = 23) recurred (17 local, six distant). Of the six distant recurrences, 50.0% had FST. With a median follow-up of 47.0 months, disease-specific survival rate was 98.8%. In multivariable analysis, R0 margins at index resection were associated with wider circumferential margins and non-FST histology. CONCLUSIONS: In this international, multicenter collaborative, DFSP practice patterns were heterogeneous but achieved favorable recurrence rates and survival. Multiple excisions to clear margins remain commonplace and can inform future efforts to optimize margin selection.

Simple Preoperative Imaging Measurements Predict Postoperative Pancreatic Fistula After Pancreatoduodenectomy.

OBJECTIVE: Postoperative pancreatic fistula is a potentially devastating complication after pancreatoduodenectomy (PD). The purpose of this study was to identify features on preoperative computed tomography (CT) imaging that correlate with an increased risk of postoperative pancreatic fistula (POPF). METHODS: Patients who underwent PD at our high-volume pancreatic surgery center from 2019 to 2021 were included if CT imaging was available within 8 weeks of surgical intervention. Pancreatic neck thickness (PNT), abdominal wall thickness (AWT), and intra-abdominal distance from pancreas to peritoneum (PTP) were measured by two board-certified radiologists who were blinded to the clinical outcomes. Radiographic measurements, as well as preoperative patient characteristics and intraoperative data, were assessed with univariate and multivariable analysis (MVA) to determine risk for clinically relevant POPF (CR-POPF, grades B and C). RESULTS: A total of 204 patients met inclusion criteria. Median PTP was 5.8 cm, AWT 1.9 cm, and PNT 1.3 cm. CR-POPF occurred in 33 of 204 (16.2%) patients. MVA revealed PTP > 5.8 cm (odds ratio [OR] 2.86, p = 0.023), PNT > 1.3 cm (OR 2.43, p = 0.047), soft pancreas consistency (OR 3.47, p = 0.012), and pancreatic duct size ≤ 3.0 mm (OR 4.55, p = 0.01) as independent risk factors for CR-POPF after PD. AWT and obesity were not associated with increased risk of CR-POPF. Patients with PTP > 5.8 cm or PNT > 1.3 cm were significantly more likely to suffer a major complication after PD (39.6% vs. 22.3% and 40% vs. 22.1%, p < 0.008). CONCLUSIONS: Patients with a thick pancreatic neck and increased intra-abdominal girth have a heightened risk of CR-POPF after pancreatoduodenectomy, and they experience more serious postoperative complications. We defined a simple CT scan-based measurement tool to identify patients at increased risk of CR-POPF.

Natural history of undifferentiated pleomorphic sarcoma: Experience from the US Sarcoma Collaborative.

BACKGROUND: Undifferentiated pleomorphic sarcoma (UPS) is a relatively rare but aggressive neoplasm. We sought to utilize a multi-institutional US cohort of sarcoma patients to examine predictors of survival and recurrence patterns after resection of UPS. METHODS: From 2000 to 2016, patients with primary UPS undergoing curative-intent surgical resection at seven academic institutions were retrospectively reviewed. Epidemiologic and clinicopathologic factors were reviewed by site of origin. Overall survival (OS), recurrence-free survival (RFS), time-to-locoregional (TTLR), time-to-distant recurrence (TTDR), and patterns of recurrence were analyzed. RESULTS: Of the 534 UPS patients identified, 53% were female, with a median age of 60 and median tumor size of 8.5 cm. The median OS, RFS, TTLR, and TTDR for the entire cohort were 109, 49, 86, and 46 months, respectively. There were no differences in these survival outcomes between extremity and truncal UPS. Compared with truncal, extremity UPS were more commonly amenable to R0 resection (87% vs. 75%, p = 0.017) and less commonly associated with lymph node metastasis (1% vs. 6%, p = 0.031). R0 resection and radiation treatment, but not site of origin (extremity vs. trunk) were independent predictors of OS and RFS. TTLR recurrence was shorter for UPS resected with a positive margin and for tumors not treated with radiation. CONCLUSION: For patients with resected extremity and truncal UPS, tumor size >5 cm and positive resection margin are associated with worse survival OS and RFS, irrespectively the site of origin. R0 surgical resection and radiation treatment may help improve these survival outcomes.

Retrospective Analysis of Retroperitoneal-Abdominal-Pelvic Ganglioneuromas: An International Study by the Transatlantic Australasian Retroperitoneal Sarcoma Working Group (TARPSWG).

OBJECTIVE: The Transatlantic Australasian Retroperitoneal Sarcoma Working Group conducted a retrospective study on the disease course and clinical management of ganglioneuromas. BACKGROUND: Ganglioneuromas are rare tumors derived from neural crest cells. Data on these tumors remain limited to case reports and single-institution case series. METHODS: Patients of all ages with pathologically confirmed primary retroperitoneal, intra-abdominal, and pelvic ganglioneuromas between January 1, 2000, and January 1, 2020, were included. We examined demographic, clinicopathologic, and radiologic characteristics, as well as clinical management. RESULTS: Overall, 328 patients from 29 institutions were included. The median age at diagnosis was 37 years with 59.1% of patients being female. Symptomatic presentation comprised 40.9% of cases, and tumors were often located in the extra-adrenal retroperitoneum (67.1%). At baseline, the median maximum tumor diameter was 7.2 cm. One hundred sixteen (35.4%) patients underwent active surveillance, whereas 212 (64.6%) patients underwent resection with 74.5% of operative cases achieving an R0/R1 resection. Serial tumor evaluations showed that malignant transformation to neuroblastoma was rare (0.9%, N=3). Tumors undergoing surveillance had a median follow-up of 1.9 years, with 92.2% of ganglioneuromas stable in size. With a median follow-up of 3.0 years for resected tumors, 84.4% of patients were disease free after resections, whereas recurrences were observed in 4 (1.9%) patients. CONCLUSIONS: Most ganglioneuromas have indolent disease courses and rarely transform to neuroblastoma. Thus, active surveillance may be appropriate for benign and asymptomatic tumors particularly when the risks of surgery outweigh the benefits. For symptomatic or growing tumors, resection may be curative.

Early experience with robotic central pancreatectomy with patient-reported outcomes and comparison with open central pancreatectomy.

BACKGROUND: Robotic central pancreatectomy (CP) has emerged in recent years as a noninferior approach to open CP and may offer improved patient-reported outcomes and reduction in incisional hernias. METHODS: All patients who underwent open and robotic CP between (2013 and 2022) were selected, and perioperative outcomes were analyzed. Patients who underwent robotic CP were interviewed over the phone to assess patient-reported postoperative outcomes. RESULTS: A total of 18 CP operations (56%-open vs. 44%-robotic) were identified. The overall median age was 67 years (interquartile range: 60-72), and 50% (n = 9) of patients were female. Median length of surgery was statistically longer for robotic CP (411 vs. 138 min, p = 0.002); all other intraoperative variables were similar. Postoperatively, a similar number of patients in the open and robotic cohorts developed clinically significant postoperative pancreatic fistulas (37.5% vs. 30%, p = 1) and major complications (37.5% vs. 20%, p = 0.60), respectively. No patients in the robotic cohort developed an incisional hernia, compared to 40% (n = 4) in open (p = 0.08). All patients returned to a baseline level of activity and reported a high quality of life. CONCLUSION: With the exception of longer operative times, robotic CP is a noninferior, definitive resection technique for select lesions of the middle pancreas. Additionally, the robotic approach may result in a reduction in incisional hernia development.

Outcomes of plastic surgical reconstruction in extremity and truncal soft tissue sarcoma: Results from the US Sarcoma Collaborative.

BACKGROUND: This study aimed to define how utilization of plastic surgical reconstruction (PSR) affects perioperative outcomes, locoregional recurrence-free survival (LRRFS), and overall survival (OS) after radical resection of extremity and truncal soft tissue sarcoma (ETSTS). The secondary aim was to determine factors associated with PSR. METHODS: Patients who underwent resection of ETSTS between 2000 and 2016 were identified from a multi-institutional database. PSR was defined as complex primary closure requiring a plastic surgeon, skin graft, or tissue-flap reconstruction. Outcomes included PSR utilization, postoperative complications, LRRFS, and OS. RESULTS: Of 2750 distinct operations, 1060 (38.55%) involved PSR. Tissue-flaps (854, 80.57%) were most commonly utilized. PSR was associated with a higher proportion of R0 resections (83.38% vs. 74.42%, p < 0.001). Tissue-flap PSR was associated with local wound complications (odds ratio: 1.81, confidence interval: 1.21-2.72, p = 0.004). Neither PSR nor postoperative complications were independently associated with LRRFS or OS. High-grade tumors (1.60, 1.13-2.26, p = 0.008) and neoadjuvant radiation (1.66, 1.20-2.30, p = 0.002) were associated with the need for PSR. CONCLUSION: Patients with ETSTS undergoing resection with PSR experienced acceptable rates of complications and a higher rate of negative margins, which were associated with improved LRRFS and OS. High tumor grade and neoadjuvant radiation were associated with requirement of PSR.

Response Evaluation of Neoadjuvant Therapies in Sarcoma.

OPINION STATEMENT: Sarcoma is a complex and heterogeneous disease with a rapidly evolving treatment landscape. With a growing emphasis on neoadjuvant therapy as a way to improve surgical and oncologic outcomes, our approach to monitor treatment efficacy must also continue to evolve. This is paramount to both clinical trial design, where endpoints must accurately reflect disease outcomes, and individual patient, whose treatment response informs therapeutic decisions. In the era of personalized medicine, the response to neoadjuvant treatment in sarcoma remains most effectively gauged by pathologic review following surgical resection. Although measures of pathologic complete response most effectively predict outcome, the requisite surgical excision precludes their use in real-time monitoring of neoadjuvant treatment response. Current image-based metrics such as RECIST and PERCIST have been utilized in many trials; however, they are limited by their unilateral measurement approach. More effective tools are needed to better measure the response to therapy prior to neoadjuvant regimen completion, so that the medication or regimen may be best tailored to patient response in an ongoing fashion. Delta-radiomics and circulating tumor DNA (ctDNA) represent promising novel tools for real-time monitoring of treatment efficacy. These metrics have been shown to predict pathologic complete response and disease progression at a superior level to traditional CT-based guidelines. Delta-radiomics is currently being utilized in a clinical trial among soft tissue sarcoma patients in which radiation dosage is adjusted based on radiomic data. The ability of ctDNA to detect molecular residual disease is also under study in multiple clinical trials, although none in the field of sarcoma. Future directions in the field include the use of ctDNA and molecular residual disease testing among sarcoma patients, as well as increased utilization of delta-radiomics, to more effectively monitor neoadjuvant treatment response prior to surgical resection.

Extremity Soft Tissue Sarcoma: A Multi-Institutional Validation of Prognostic Nomograms.

BACKGROUND: Prognostic nomograms for patients with resected extremity soft tissue sarcoma (STS) include the Sarculator and Memorial Sloan Kettering (MSKCC) nomograms. We sought to validate these two nomograms within a large, modern, multi-institutional cohort of resected primary extremity STS patients. METHODS: Resected primary extremity STS patients from 2000 to 2017 were identified across nine high-volume U.S. institutions. Predicted 5- and 10-year overall survival (OS) and distant metastases cumulative incidence (DMCI), and 4-, 8-, and 12-year disease-specific survival (DSS) were calculated with Sarculator and MSKCC nomograms, respectively. Predicted survival probabilities stratified in quintiles were compared in calibration plots to observed survival assessed by Kaplan-Meier estimates. Cumulative incidence was estimated for DMCI. Harrell's concordance index (C-index) assessed discriminative ability of nomograms. RESULTS: A total of 1326 patients underwent resection of primary extremity STS. Common histologies included: undifferentiated pleomorphic sarcoma (35%), fibrosarcoma (13%), and leiomyosarcoma (9%). Median tumor size was 8.0 cm (IQR 4.5-13.0). Tumor grade distribution was: Grade 1 (13%), Grade 2 (9%), Grade 3 (78%). Median OS was 172 months, with estimated 5- and 10-year OS of 70% and 58%. C-indices for 5- and 10-year OS (Sarculator) were 0.72 (95% CI 0.70-0.75) and 0.73 (95% CI 0.70-0.75), and 0.72 (95% CI 0.69-0.75) for 5- and 10-year DMCI. C-indices for 4-, 8-, and 12-year DSS (MSKCC) were 0.71 (95% CI 0.68-0.75). Calibration plots showed good prognostication across all outcomes. CONCLUSIONS: Sarculator and MSKCC nomograms demonstrated good prognostic ability for survival and recurrence outcomes in a modern, multi-institutional validation cohort of resected primary extremity STS patients. External validation of these nomograms supports their ongoing incorporation into clinical practice.

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.

The aborted Whipple: Why, and what happens next?

BACKGROUND: For patients with periampullary adenocarcinoma (PAC), pancreatoduodenectomy (PD) provides the best survival. Surgery on a subset of patients is aborted during PD. We analyzed these patients. METHODS: Patients who underwent laparotomy for planned PD for PAC were identified (2006-2019). From operative notes, we identified the subset with intraoperative decision to abort. Patient, treatment, and outcome data were analyzed. The subset with pancreatic ductal adenocarcinoma (PDAC) was analyzed for survival. RESULTS: Only 6.7% (n = 55/819) of cases were aborted. Majority 78% (n = 43) had pathologically-confirmed diagnoses at time of surgery, and 18.2% (n = 10) received preoperative chemotherapy. Reasons for aborted PD included: distant metastases (65.5%, n = 36) and local invasion (34.5%, n = 19). Of patients with metastatic disease, 75% (n = 27) had liver metastases. Eighty-nine percent (n = 49) of patients underwent at least one palliative bypass procedure and 81.8% (n = 45) had both gastric and biliary bypass. Patients with computed tomography (CT) scans before surgery more commonly had missed metastatic disease (79.2% CT compared to 54.8% magnetic resonance imaging [MRI], χ2 = 3.54, p = 0.059). In PDAC, 61.4% (n = 27/44) were aborted for metastatic disease and 38.7% (n = 17/44) for local invasion. Median overall survival for all PDAC patients after aborted PD was 334 days. CONCLUSION: Majority of pancreatoduodenectomies for periampullary adenocarcinoma are done to completion. Liver metastases is the most common reason for aborting. Preoperative MRI may help identify hepatic metastases.

Resection of retroperitoneal tumors with inferior vena cava involvement without caval reconstruction.

BACKGROUND AND OBJECTIVES: Retroperitoneal tumors with involvement of the inferior vena cava (IVC) often require resection of the IVC to achieve complete tumor removal. This study evaluates the safety and efficacy of IVC ligation without caval reconstruction. METHODS: A retrospective chart review of patients who underwent IVC ligation (IVC-Ligation) and IVC resection with reconstruction (IVC-Reconstruction) at our institution between May 2004 and April 2021 was performed. Outcomes from the two surgical techniques were compared via univariate analysis using the Kruskal-Wallis test for continuous variables and Fisher's exact test for categorical variables. RESULTS: Forty-nine IVC-Ligation and six IVC-Reconstruction surgeries were identified. There were no differences in baseline demographics, tumor characteristics, complication rates, postoperative morbidity, or overall 5-year survival between groups. IVC-Reconstruction patients were more likely to require intensive care unit admission (83% vs. 33%; p = 0.0257) and the IVC-Ligation cohort had a tendency to present with nondebilitating postoperative lymphedema (35% vs. 0%; p = 0.1615), which resolved for most patients. CONCLUSIONS: IVC-Ligation is a viable surgical option for select patients presenting with retroperitoneal tumors with IVC involvement and provides acceptable short- and medium-term outcomes.

Extraskeletal myxoid chondrosarcoma: Clinicopathological features and outcomes from the United States sarcoma collaborative database.

BACKGROUNDS AND OBJECTIVES: This investigation described clinicopathological features and outcomes of extraskeletal myxoid chondrosarcoma (EMC) patients. METHODS: EMC patients were identified from the United States Sarcoma Collaborative database between 2000 and 2016. Overall survival (OS) and recurrence-free survival (RFS) were calculated, and prognostic factors were analyzed. RESULTS: Sixty individuals with a mean age of 55 years were included, and 65.0% (n = 39) were male. 73.3% (n = 44) had a primary tumor. A total of 41.6% (n = 25) developed tumor relapse following resection. The locoregional recurrence rate was 30.0% (n = 18/60), and mean follow-up was 42.7 months. The 5-year OS was 71.0%, while the 5-year RFS was 41.4%. On multivariate analysis for all EMC, chemotherapy (hazard ratio [HR], 6.054; 95% confidence interval [CI], 1.33-27.7; p = 0.020) and radiation (HR, 5.07, 95% CI, 1.3-20.1; p = 0.021) were independently predictive of a worse RFS. Among patients with primary EMC only, the 5-year OS was 85.3%, with a 30.0% (n = 12) locoregional recurrence rate, though no significant prognostic factors were identified. CONCLUSIONS: Long-term survival with EMC is probable, however there exists a high incidence of locoregional recurrence. While chemotherapy and radiation were associated with a worse RFS, these findings were likely confounded by recurrent disease as significance was lost in the primary EMC-only subset.

Defining the role of neoadjuvant systemic therapy in high-risk retroperitoneal sarcoma: A multi-institutional study from the Transatlantic Australasian Retroperitoneal Sarcoma Working Group.

BACKGROUND: In patients with retroperitoneal sarcoma (RPS), the incidence of recurrence after surgery remains high. Novel treatment approaches are needed. This retrospective study evaluated patients with primary, high-risk RPS who received neoadjuvant systemic therapy followed by surgery to 1) determine the frequency and potential predictors of radiologic tumor responses and 2) assess clinical outcomes. METHODS: Clinicopathologic data were collected for eligible patients treated at 13 sarcoma referral centers from 2008 to 2018. Univariable and multivariable logistic models were performed to assess the association between clinical predictors and response. Overall survival (OS) and crude cumulative incidences of local recurrence and distant metastasis were compared. RESULTS: Data on 158 patients were analyzed. A median of 3 cycles of neoadjuvant systemic therapy (interquartile range, 2-4 cycles) were given. The regimens were mostly anthracycline based; however, there was significant heterogeneity. No patients demonstrated a complete response, 37 (23%) demonstrated a partial response (PR), 88 (56%) demonstrated stable disease, and 33 (21%) demonstrated progressive disease (PD) according to the Response Evaluation Criteria in Solid Tumors, version 1.1. Only a higher number of cycles given was positively associated with PR (P = .005). All patients underwent complete resection, regardless of the tumor response. Overall, patients whose tumors demonstrated PD before surgery showed markedly worse OS (P = .005). An indication of a better clinical outcome was seen in specific regimens given for grade 3 dedifferentiated liposarcoma and leiomyosarcoma. CONCLUSIONS: In patients with high-risk RPS, the response to neoadjuvant systemic therapy is fair overall. Disease progression on therapy may be used to predict survival after surgery. Subtype-specific regimens should be further validated.

Should Signet Ring Cell Histology Alter the Treatment Approach for Clinical Stage I Gastric Cancer?

BACKGROUND: Surgery alone is standard-of-care for stage I gastric adenocarcinoma; however, clinicians can offer preoperative therapy for clinical stage I disease with signet ring cell histology, given its presumed aggressive biology. We aimed to assess the validity of this practice. METHODS: The National Cancer Database (2004-2015) was reviewed for patients with clinical stage I signet ring cell gastric adenocarcinoma who underwent treatment with surgery alone, perioperative chemotherapy, neoadjuvant therapy, or adjuvant therapy. Analysis was stratified by preoperative clinical/pathologic stage. Primary outcome was overall survival (OS). RESULTS: Of 1018 patients, median age was 60 years (±14); 53% received surgery alone (n = 542), 5% received perioperative chemotherapy (n = 47), 12% received neoadjuvant therapy (n = 125), and 30% received adjuvant therapy (n = 304). For clinical stage I disease, surgery alone was associated with an improved 5-year OS rate (71%) versus perioperative chemotherapy (58%), neoadjuvant therapy (38%), or adjuvant therapy (52%) [overall p < 0.01]. For pathologic stage I, surgery alone had equivalent or improved survival compared with perioperative, neoadjuvant, and adjuvant therapy (5-year OS: 78% vs. 89% [p = 0.77] vs. 64% [p = 0.04] vs. 84% [p = 0.99]). Adjuvant therapy was associated with improved 5-year OS compared with pretreatment for those patients upstaged (37%) to pathologic stage II/III (55% vs. 36% and 34% vs. 7%; all p < 0.01). CONCLUSIONS: This stage-specific study demonstrates improved survival with surgery alone for clinical stage I signet ring cell gastric adenocarcinoma. Despite 37% of clinical stage I patients being upstaged to pathologic stage II/III, adjuvant therapy offers a favorable rescue strategy, with improved outcomes compared with those treated preoperatively. Surgery alone also affords similar or improved survival for pathologic stage I disease versus multimodality therapy. This study challenges the bias to overtreat stage I signet ring cell gastric adenocarcinoma.

Renal Function After Retroperitoneal Sarcoma Resection with Nephrectomy: A Matched Analysis of the United States Sarcoma Collaborative Database.

BACKGROUND: Nephrectomy often is required during en bloc resection of a retroperitoneal sarcoma (RPS) to achieve an R0 or R1 resection. The impact of nephrectomy on postoperative renal function in this patient population, who also may benefit from subsequent nephrotoxic systemic therapy, is not well described. METHODS: The United States Sarcoma Collaborative (USSC) database was queried for patients undergoing RPS resection between 2000 and 2016. Patients with missing pre- or postoperative measures of renal function were excluded. A matched cohort was created using coarsened exact matching. Weighted logistic regression was used to control further for differences between the nephrectomy and non-nephrectomy cohorts. The primary outcomes were postoperative acute kidney injury (AKI), acute renal failure (ARF), and dialysis. RESULTS: The initial cohort consisted of 858 patients, 3 (0.3%) of whom required postoperative dialysis. The matched cohort consisted of 411 patients, 108 (26%) of whom underwent nephrectomy. The patients who underwent nephrectomy had higher rates of postoperative AKI (14.8% vs 4.3%; p < 0.01) and ARF (4.6% vs 1.3%; p = 0.04), but no patients required dialysis postoperatively. Logistic regression modeling showed that the risk of AKI (odds ratio [OR], 5.16; p < 0.01) and ARF (OR 5.04; p < 0.01) after nephrectomy persisted despite controlling for age and preoperative renal function. CONCLUSIONS: Nephrectomy is associated with an increased risk of postoperative AKI and ARF after RPS resection. This study was unable to statistically assess the impact of nephrectomy on postoperative dialysis, but the risk of postoperative dialysis is 0.5% or less regardless of nephrectomy status.

Relationship between Cancer Diagnosis and Complications Following Pancreatoduodenectomy for Duodenal Adenoma.

BACKGROUND: Pancreatoduodenectomy (PD) for duodenal adenoma (DA) resection may be associated with excessive surgical risk for patients with potentially benign lesions, given the absence of pancreatic duct obstruction. We examined factors associated with final malignant pathology and evaluated the postoperative course of patients with DA versus pancreatic ductal adenocarcinoma (PDAC). METHODS: We retrospectively analyzed patients with DA who underwent PD from 2008 to 2018 and assessed the accuracy rate of preoperative biopsy and factors associated with final malignant pathology. Complications for DA patients were compared with those of matched PDAC patients. RESULTS: Forty-five consecutive patients who underwent PD for DA were identified, and the preoperative biopsy false negative rate was 29. Factors associated with final malignant pathology included age over 70 years, preoperative biliary obstruction, and common bile duct diameter > 8 mm (p < 0.05). Compared with patients with PDAC (n = 302), DA patients experienced more major complications (31% vs. 15%, p < 0.01), more grade C postoperative pancreatic fistulas (9% vs. 1%, p < 0.01), and greater mortality (7% vs. 2%, p < 0.05). Propensity score matched patients with DA had more major complications following PD (32% vs. 12%, p < 0.05). CONCLUSIONS: Preoperative biopsy of duodenal adenomas is associated with a high false-negative rate for malignancy, and PD for DA is associated with higher complication rates than PD for PDAC. These results aid discussion among patients and surgeons who are considering observation versus PD for DA, especially in younger patients without biliary obstruction, who are less likely to harbor malignancy.

Postoperative Morbidity After Resection of Recurrent Retroperitoneal Sarcoma: A Report from the Transatlantic Australasian RPS Working Group (TARPSWG).

BACKGROUND: This study aimed to evaluate perioperative morbidity after surgery for first locally recurrent (LR1) retroperitoneal sarcoma (RPS). Data concerning the safety of resecting recurrent RPS are lacking. METHODS: Data were collected on all patients undergoing resection of RPS-LR1 at 22 Trans-Atlantic Australasian Retroperitoneal Sarcoma Working Group (TARPSWG) centers from 2002 to 2011. Uni- and multivariable logistic models were fitted to study the association between major (Clavien-Dindo grade ≥ 3) complications and patient/surgery characteristics as well as outcome. The resected organ score, a method of standardizing the number of organs resected, as previously described by the TARPSWG, was used. RESULTS: The 681 patients in this study had a median age of 59 years, and 51.8% were female. The most common histologic subtype was de-differentiated liposarcoma (43%), the median resected organ score was 1, and 83.3% of the patients achieved an R0 or R1 resection. Major complications occurred for 16% of the patients, and the 90-day mortality rate was 0.4%. In the multivariable analysis, a transfusion requirement was found to be a significant predictor of major complications (p < 0.001) and worse overall survival (OS) (p = 0.010). However, having a major complication was not associated with a worse OS or a higher incidence of local recurrence or distant metastasis. CONCLUSIONS: A surgical approach to recurrent RPS is relatively safe and comparable with primary RPS in terms of complications and postoperative mortality when performed at specialized sarcoma centers. Because alternative effective therapies still are lacking, when indicated, resection of a recurrent RPS is a reasonable option. Every effort should be made to minimize the need for blood transfusions.

Analysis of Differentiation Changes and Outcomes at Time of First Recurrence of Retroperitoneal Liposarcoma by Transatlantic Australasian Retroperitoneal Sarcoma Working Group (TARPSWG).

BACKGROUND: Local recurrence following resection of retroperitoneal liposarcoma (RLPS) is common. Well-differentiated (WD) and dedifferentiated (DD) RLPS are distinct entities with differing outcomes. A few reports suggest that WDLPS can recur as DDLPS and that DDLPS can recur as WDLPS. This study evaluates whether this change in differentiation from the primary tumor to the first local recurrence impacts long-term outcomes. METHODS: Retrospective review from 22 sarcoma centers identified consecutive patients who underwent resection for a first locally recurrent RLPS from January 2002 to December 2011. Outcomes measured included overall survival, local recurrence, and distant metastasis. RESULTS: A total of 421 RPLS patients were identified. Of the 230 patients with primary DDLPS, 34 (15%) presented WDLPS upon recurrence (DD → WD); and of the 191 patients with primary WDLPS, 54 (28%) presented DDLPS upon recurrence (WD → DD). The 6-year overall survival probabilities (95% CI) for DD → DD, DD → WD, WD → WD, and WD → DD were 40% (32-48%), 73% (58-92%), 76% (68-85%), and 56% (43-73%) (p < 0.001), respectively. The 6-year second local recurrence incidence was 66% (59-73%), 63% (48-82%), 66% (57-76%), and 77% (66-90%), respectively. The 6-year distant metastasis incidence was 13% (9-19%), 3% (0.4-22%), 5% (2-11%), and 4% (1-16%), respectively. On multivariable analysis, DD → WD was associated with improved overall survival when compared with DD → DD (p < 0.001). Moreover, WD → DD was associated with a higher risk of LR (p = 0.025) CONCLUSION: A change in RLPS differentiation from primary tumor to first local recurrence appears to impact survival. These findings may be useful in counseling patients on their prognosis and subsequent management.

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.