Retroperitoneal sarcomas: combined modality treatment approaches

IOeRT in retroperitoneal sarcoma: Towards more organ preservation with comparable oncological outcomes

BACKGROUND

Retroperitoneal sarcomas (RPS) present a surgical challenge with high rates of local recurrence (LR). We investigated the role of intraoperative electron radiotherapy (IOeRT) in reducing LR after surgical resection of RPS.

METHODS

A retrospective analysis of all patients who underwent surgical resection for RPS between 2014 and 2021 at a tertiary academic referral center (n = 172). Patients included underwent surgical resection of their RPS and received IOeRT (n = 36) and were compared by case control matching to patients with similar tumor characteristics (recurrence status and tumor grade) that did not receive IOeRT (n = 36).

RESULTS

The median length of hospitalization was 8 days (range, 4-34) in the IOeRT group and 10 days (range, 2-42) in the non-IOeRT group (p = 0.25). The mean operating room (OR) time was 4h (±1.3) and 4h (±1.9) in the IOeRT and non-IOeRT groups respectively, (p = 0.37). Complete resection with R0 margins was achieved in 30 patients (83.3%) and 24 patients (66.6%) in the IOeRT and non-IOeRT groups, respectively (p = 0.1). R1 resection was achieved in 6 patients (16.6%) and 12 patients (33.3%) respectively, (p = 0.1). The resected organ weighted score was significantly different between the groups; score 0 observed in 19 (52.7%) patients in the IOeRT group and 3 (8.3%) in the non-IOeRT group (p < 0.001), score 1 observed in 7 (19.4%) in the IOeRT group and 17 (47.2%) in the non-IOeRT group (p = 0.012). The rate of severe complications (CD score>3) did not differ between the groups, 5 (13.8%) patients in the IOeRT group and 9 (25%) patients in the non-IOeRT group (p = 0.23). No radiation associated complications were noted. The 2-year local recurrence free survival (LRFS) was 75.9% in the IOeRT group and 60.3% in the non-IOeRT group (p = 0.4). The 2-year IOeRT field recurrent free survival (IRFS) was 88.4% in the IOeRT group and 60.3% in the non-IOeRT group (p = 0.04).

CONCLUSIONS

The use of IOeRT did not increase the rate of surgical complications and was associated with superior local control in the radiation field, improved organ preservation without an impact on overall survival.

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.

Conditional survival after surgical resection of primary retroperitoneal tumors: a population-based study

Background

The purpose of this study was to assess conditional survival (CS) after resection of primary retroperitoneal tumors (RPTs).

Methods

The data of 1594 patients with primary RPTs who underwent surgery between 2004 and 2016 were retrieved from the Surveillance Epidemiology and End Results (SEER) database. Multivariate Cox analysis was used to identify prognostic factors affecting overall survival (OS) and cancer-specific survival (CSS). CS was used to calculate the probability of survival for an additional 3 years after the patient had survived x years, according to the formulas: COS3 = OS (x + 3) /OS (x) and CCSS3 = CSS (x + 3)/CSS (x).

Results

The 1-, 3-, and 5-year OS rates of all patients were 89.8, 71.8, and 60.8%, while the 1-, 3-, and 5-year CSS rates were 91.9, 77.1, and 67.8%, respectively. Age, sex, FNCLCC grade, size, multifocality, histology, and chemotherapy were independent prognostic factors for OS and CSS. Among patients who survived for 1, 3, and 5 years, the COS3 rates were 72.9, 77.9, and 79.3%, and the CCSS3 rates were 78.1, 82.7, and 85.8%, respectively. Patients with poor clinicopathological characteristics achieved greater improvements in COS3 and CCSS3 rates, and the survival gaps between OS and COS3, as well as CSS and CCSS3 were more obvious.

Conclusion

Postoperative CS of RPTs was dynamic and increased over time. CS increased more significantly in patients with poor clinicopathological characteristics.

Unsupervised versus Supervised Identification of Prognostic Factors in Patients with Localized Retroperitoneal Sarcoma: A Data Clustering and Mahalanobis Distance Approach

The aim of this report is to unveil specific prognostic factors for retroperitoneal sarcoma (RPS) patients by univariate and multivariate statistical techniques. A phase I-II study on localized RPS treated with high-dose ifosfamide and radiotherapy followed by surgery (ISG-STS 0303 protocol) demonstrated that chemo/radiotherapy was safe and increased the 3-year relapse-free survival (RFS) with respect to historical controls. Of 70 patients, twenty-six developed local, 10 distant, and 5 combined relapse. Median disease-free interval (DFI) was 29.47 months. According to a discriminant function analysis, DFI, histology, relapse pattern, and the first treatment approach at relapse had a statistically significant prognostic impact. Based on scientific literature and clinical expertise, clinicopathological data were analyzed using both a supervised and an unsupervised classification method to predict the prognosis, with similar sample sizes (66 and 65, resp., in casewise approach and 70 in mean-substitution one). This is the first attempt to predict patients' prognosis by means of multivariate statistics, and in this light, it looks noticable that (i) some clinical data have a well-defined prognostic value, (ii) the unsupervised model produced comparable results with respect to the supervised one, and (iii) the appropriate combination of both models appears fruitful and easily extensible to different clinical contexts.

[Liposarcoma in the renal compartment: about two cases and literature review]

Retroperitoneal sarcomas are rare and heterogeneous tumors. We here report two cases of liposarcoma in the renal compartment with a literature review in order to emphasize on the anatomical and surgical features of this tumor location and on its possible prognostic implications. The first reported case was a 45-year old female patient with liposarcoma at the level of the left renal compartment. The diagnosis of myxoid liposarcoma was based on anatomo-pathological examination of the surgical specimen. The second reported case was a 70-year old man with liposarcoma at the level of the right renal compartment. The diagnosis of dedifferentiated liposarcoma was based on anatomo-pathological examination of the surgical specimen. Retroperitoneal sarcomas are often diagnosed with a palpable mass. The gold standard treatment is complete tumor resection with healthy resection margins and without damage or rupture. For this purpose resection involving adjacent organs is recommended by some authors. However the anatomical constraints of tretroperitoneal compartment and the often important tumor volume limit the possibilities to achieve a satisfactory resection. CT scan and MRI are very useful imaging techniques. Histological diagnosis poses some problems; therefore immunohistochemistry and sometimes molecular biology are significantly helpful. Patient evolution is marked by the frequent occurrence of recurrences. A specialized multidisciplinary management of these rare and very varied tumors is recommended in order to optimize therapeutic outcomes.

Acute haemorrhage from a retroperitoneal liposarcoma: a rare presentation

A previously healthy 61-year-old Caucasian woman presented to the emergency department after collapsing at home with associated abdominal pain radiating to her back. An urgent CT angiogram was requested to rule out a ruptured aortic aneurysm. This showed a large 21 cm fat-containing lesion arising from the mid-pole of the left kidney, with an adjacent 4 cm perirenal haematoma. An initial diagnosis of a ruptured angiomyolipoma was made. Her haemoglobin was 105 g/L, with a creatinine of 104 mmol/L and an eGFR of 47 mL/min. Her clotting profile was normal. Following resuscitation, she was taken to the operating room and underwent an emergency open left radical nephrectomy via a left flank incision. Her recovery was uneventful and she was discharged home after 6 days. The histopathology confirmed a well-differentiated liposarcoma.

Retroperitoneal Sarcomas

BACKGROUND

The evaluation and treatment of retroperitoneal sarcomas are challenging because the tumors are relatively rare and frequently present with advanced disease in an anatomically complex location.

METHODS

We reviewed the literature on experience in the management of retroperitoneal sarcomas, and we present our own experience in the treatment of these tumors.

RESULTS

The identification of prognostic factors other than the adequacy of resection has been inconsistent. Due to a lack of associated symptoms, retroperitoneal sarcomas smaller than 5 cm are rare. Computed tomography is the most useful tool in the evaluation of retroperitoneal tumors. Surgery, radiation therapy, and chemotherapy are treatment options, but the most important factor in the treatment of primary tumors is complete surgical resection. The role of neoadjuvant and adjuvant therapies is not defined and should be considered within the context of clinical trials.

CONCLUSIONS

Early referral of patients with retroperitoneal soft tissue tumors will help to ensure that they will receive the benefits of multidisciplinary evaluation and treatment of their disease and ready access to clinical trials.

Phase 1 trial of preoperative image guided intensity modulated proton radiation therapy with simultaneously integrated boost to the high risk margin for retroperitoneal sarcomas

PURPOSE

To conduct phase 1 and 2 trials with photon intensity modulated radiation therapy and intensity modulated proton therapy (IMPT) arms to selectively escalate the retroperitoneal sarcoma preoperative radiation dose to tumor volume (clinical target volume [CTV] 2) that is judged to be at a high risk for positive margins and aim to reduce local recurrence. We report on the IMPT study arm in phase 1.

METHODS AND MATERIALS

Patients aged ≥18 years with primary or locally recurrent retroperitoneal sarcoma were treated with preoperative IMPT, 50.4 GyRBE in 28 fractions, to CTV1 (gross tumor volume and adjacent tissues at risk of subclinical disease) with a simultaneous integrated boost to CTV2 to doses of 60.2, 61.6, and 63.0 GyRBE in 28 fractions of 2.15, 2.20, and 2.25 GyRBE, respectively. The primary objective of the phase 1 study was to determine the maximum tolerated dose to CTV2, which will be further tested in the phase 2 study.

RESULTS

Eleven patients showed increasing IMPT dose levels without acute dose limiting toxicities that prevented dose escalation to maximum tolerated dose. Acute toxicity was generally mild with no radiation interruptions. No unexpected perioperative morbidity was noted. Eight months postoperatively, one patient developed hydronephrosis that was treated by stent with ureter dissected off tumor and received 57.5 GyRBE. Retained ureter(s) was (were) subsequently constrained to 50.4 GyRBE without further problem. With an 18-month median follow-up, there were no local recurrences.

CONCLUSIONS

IMPT dose escalation to CTV2 to 63 GyRBE was achieved without acute dose limiting toxicities. The phase 2 study of IMPT will accrue patients to that dose. Parallel intensity modulated radiation therapy phase 1 arm is currently accruing at the initial dose level. Ureters that undergo a high dose radiation and/or surgery are at risk for late hydro-ureter. Future studies will constrain retained ureters to 50.4 GyRBE to avoid ureteral stricture.

Recurrence and survival analysis of resected soft tissue sarcomas of pelvic retroperitoneal structures

BACKGROUND

The purpose is to determine the clinicopathologic factors related to survival and recurrence of primary resected pelvic soft tissue sarcomas (STS).

METHODS

Demographic/clinical variables were recorded.

RESULTS

Thirty-five pts were identified. Median follow-up was 24.2 months. There were 23 (65.7%) high/intermediate-grade and 12 (34.3%) low-grade tumors included in the final analysis. Eight patients (22.9%) received neoadjuvant therapy. Margins were grossly negative in 27 (77.1%, 17-R0, 10-R1) and grossly positive (R2) in 8 (22.9%). Adjuvant therapy was used in 13 patients (37.1%). The 2- and 3-year RFS was 56.5% and 51.3%, with 14 patients recurring at a median time of 16 months (6-local, 8-distant). All distant recurrences were in high-grade tumors. There were no differences in RFS for margins (R0 vs. R1), neoadjuvant/adjuvant therapy, size (≥10 vs. <10 cm) or gender. High/intermediate-grade tumors had worse RFS (P < 0.008). The 2- and 3-year OS was 80.9%. OS was improved for R0/R1 resection (P < 0.001). Resection to R0/R1 margin was a significant predictor of improved OS (P = 0.001).

CONCLUSIONS

High/intermediate-grade lesions were associated with worse OS and RFS. Resection to gross negative margins was the only independent predictor of OS. Adjuvant therapy may be reserved for high-grade lesions due to increased metastatic potential. J

Curved incision under the costal margin in retroperitoneal tumor surgery

This study was conducted to investigate the value of using a curved incision under the costal margin in retroperitoneal tumor surgery. Data on 68 patients with retroperitoneal tumors were reviewed. Of the 68 patients, 32 underwent tumor removal via a curved incision under the costal margin (group A) and the remaining 36 patients underwent a mid-abdominal oblique incision at the waist (group B). The patient outcomes were compared between the two groups to analyze the effects of the different types of incision on the completeness of resection, duration of operation, intraoperative blood loss, postoperative recovery time and surgical complications. The tumors from the 32 patients in group A were all successfully removed and the outcomes of the patients in group A, regarding tumor removal, duration of operation, amount of blood lost and surgical complications, were superior to those of the patients in group B. A route of incision is required that adequately exposes the internal limit or lower boundary of the tumor and ensures adequate surgical field visualization. The 32 patients underwent retroperitoneal tumor removal via a curved incision under the costal margin, plus a longitudinal incision along the lower boundary of the tumor at the midline of the abdomen. All the patients underwent complete tumor resection and recovered well after surgery, without necrosis at the incision site. In terms of duration of the operation, blood transfusion volume, mean length of hospital stay, weight of tumor removed, perioperative mortality, postoperative intestinal fistulas and rate of complete surgical resection, the outcomes of the patients in group A were superior to those of group B.

CT perfusion as an imaging biomarker in monitoring response to neoadjuvant bevacizumab and radiation in soft-tissue sarcomas: comparison with tumor morphology, circulating and tumor biomarkers, and gene expression

OBJECTIVE

The purpose of this study was to evaluate the role of CT perfusion in monitoring response to neoadjuvant antiangiogenic and radiation therapy in resectable soft-tissue sarcomas and correlate the findings with tumor size, circulating and tumor biomarkers, and gene expression.

SUBJECTS AND METHODS

This phase II clinical trial included 20 patients (13 men and 7 women; mean age, 55 years) with soft-tissue sarcomas who were undergoing treatment with the antiangiogenic drug bevacizumab followed by bevacizumab, radiation, and surgical resection. The patients underwent CT perfusion and diagnostic contrast-enhanced CT at baseline, at 2 weeks after bevacizumab therapy, and after completion of bevacizumab and radiation therapy. Multiple CT perfusion parameters (blood flow, blood volume, mean transit time, and permeability) were correlated with tumor size, circulating and tumor biomarkers, and gene expression.

RESULTS

Two weeks after bevacizumab therapy, there was substantial fall in blood volume (31.9% reduction, p = 0.01) with more pronounced reduction in blood flow, blood volume, and permeability after treatment completion (53-64% reduction in blood flow, blood volume, and permeability; p = 0.001), whereas tumor size showed no significant change (p = 0.34). Tumors with higher baseline blood volume and lower baseline tumor size showed superior response to bevacizumab and radiation (p = 0.05). There was also an increase in median plasma vascular endothelial growth factor and placental-derived growth factor concentration after bevacizumab therapy paralleled by a decrease in tumor perfusion depicted by CT perfusion, although this was not statistically significant (p = 0.4). The baseline tumor microvessel density (MVD) correlated with blood flow (p = 0.04). At least 20 different genes were differentially expressed in tumors with higher and lower baseline perfusion.

CONCLUSION

CT perfusion is more sensitive than tumor size for monitoring early and late response to bevacizumab and radiation therapy. CT perfusion parameters correlate with MVD, and the gene expression levels of baseline tumors could potentially predict treatment response.

Role of radiation therapy for non-extremity soft tissue sarcomas

BACKGROUND

Negative surgical margins are uncommon for non-extremity soft tissue sarcomas. Radiation therapy is usually recommended to improve local control; however, appropriate RT dosing is challenging due to nearby dose-limiting normal structures.

MATERIAL AND METHODS

Comprehensive literature search using PubMed (March 2014).

RESULTS

Data suggest radiation therapy is an important modality in maximizing local tumor control in non-extremity sarcomas.

CONCLUSION

The literature supports the use of RT to improve local control for non-extremity soft tissue sarcomas.

Accuracy of preoperative percutaneous biopsy for the diagnosis of retroperitoneal liposarcoma subtypes

BACKGROUND

Surgery is the primary treatment for all subtypes of retroperitoneal liposarcoma, but neoadjuvant therapy may be warranted in cases of dedifferentiated liposarcoma (DDLS), which has an increased risk of recurrence and metastasis. Therefore, an accurate subtype-specific diagnosis is vital for appropriate consideration of neoadjuvant therapy. Previous studies assessing the subtype-specific accuracy of percutaneous biopsy are limited. We aimed to analyze the accuracy of preoperative percutaneous biopsy in the subtype-specific diagnosis of retroperitoneal liposarcoma and thus the reliability of percutaneous biopsy in guiding decisions about neoadjuvant treatment.

METHODS

We retrospectively reviewed the medical records, including the pathologic reports, interventional radiology reports, and operative reports, of patients registered in the retroperitoneal/well-differentiated liposarcoma (WDLS/DDLS) database at The University of Texas MD Anderson Cancer Center between 1993 and 2013.

RESULTS

We identified 120 patients who underwent 137 preoperative percutaneous biopsies followed by surgical resections. Pathologic examination following resection indicated that 74 of the patients had WDLS and 63 had DDLS. The overall diagnostic accuracy of percutaneous biopsy for identifying the subtype of liposarcoma was 62.8 % (86/137); the accuracy for identifying WDLS was significantly higher (85.1 %; 63/74) than that for identifying DDLS (36.5 %; 23/63) (p < 0.01).

CONCLUSIONS

Percutaneous biopsy has low accuracy in the diagnosis of retroperitoneal DDLS. This can potentially mislead physicians in the decision to implement neoadjuvant treatment. When developing treatment strategies, including clinical trials for patients with retroperitoneal liposarcoma, physicians should carefully consider the low accuracy of percutaneous biopsy in detecting DDLS.

Favorable control of rapidly progressive retroperitoneal pleomorphic leiomyosarcoma with multimodality therapy: a case report

BACKGROUND

Retroperitoneal sarcomas (RPS), such as pleomorphic leiomyosarcoma, often invade or displace vital organs in the abdominal cavity and exhibit an aggressive clinical course. Complete surgical resection of the tumor and preoperative radiotherapy and chemotherapies can be used for non-metastatic RPS. However, in case of huge retroperitoneal sarcoma fully occupying the abdominal cavity, surgical resection tends to be insufficient, resulting in poor outcomes. This report describes a case of rapidly progressive retroperitoneal pleomorphic leiomyosarcoma that was favorably controlled by debulking surgery followed by combination chemotherapy and radiotherapy.

CASE PRESENTATION

A 65-year-old Japanese woman developed abdominal discomfort due to a huge retroperitoneal tumor fully occupying the abdominal cavity. The immunohistochemical diagnosis was pleomorphic leiomyosarcoma with high-grade malignancy and aggressive proliferative features. Debulking surgery could be performed, but the small residual tumor had rapidly grown to an approximately 22 cm in length on the major axis within 38 days after the operation. The patient's general condition progressively declined. Combination chemotherapy, consisting of doxorubicin and ifosfamide, was successfully administered for six cycles while maintaining dose intensity. The best objective response was a partial response, and the chemotherapy was well tolerated. Approximately 50 Gy of radiotherapy was delivered to the remaining tumor. This multimodal strategy resulted in progression-free survival for more than 17 months and achieved sustained symptomatic relief.

CONCLUSIONS

Multimodal therapy with debulking surgery, combination chemotherapy and radiotherapy controlled a rapidly progressive retroperitoneal pleomorphic leiomyosarcoma. Maintaining dose intensity of the chemotherapy and radiotherapy might contribute to overall tumor control.

Current concepts in multimodality therapy for retroperitoneal sarcoma

Radical surgical resection currently represents the most effective therapy for patients with retroperitoneal sarcoma. Unfortunately, margin-negative resection often mandates extirpation of multiple retroperitoneal viscera, and such operations are nonetheless fraught with high rates of locoregional recurrence. In an attempt to improve local control and ultimately survival, adjuvant strategies of radiation and chemotherapy have been increasingly employed, with promising results. To date, however, the rarity of the disease has limited large, prospective studies investigating the efficacy of these adjuvant modalities. In this article, we review the current literature pertaining to the diagnosis, staging and treatment of retroperitoneal sarcoma and demonstrate the critical need for future large, multi-institutional studies to advance our knowledge of this uncommon disease.

Preoperative radiation for retroperitoneal sarcoma is not associated with increased early postoperative morbidity

BACKGROUND AND OBJECTIVES

Preoperative radiation (PR) in the management of retroperitoneal sarcoma (RPS) is controversial. Concern for increased perioperative morbidity may influence the decision to recommend PR. Here we compare 30-day morbidity and mortality (M + M) after resection of RPS with and without PR.

METHODS

Patients undergoing resection of RPS were identified using ACS NSQIP (2005-2011). Patients with known PR status within 90 days of operation were included. Univariate and multivariate logistic regression analyses were performed to identify factors associated with M + M.

RESULTS

Of 696 patients operated on for RPS, 70 (10%) underwent PR. PR patients were younger (mean 55 vs. 61 years), more frequently had hypoalbuminemia (<3 g/dl; 19% vs. 10%), concomitant kidney (29% vs. 18%), or pancreas resections (11% vs. 5%), longer operations (mean 327 vs. 253 min), and increased transfusion requirements (mean 4.1 vs. 2.1 units, each P < 0.05). Despite these differences, the M + M rate (31% with vs. 30% without PR, P = 0.75) was comparable between the two groups. After adjustment for confounders, no association was identified between PR and M + M.

CONCLUSIONS

In a national cohort of RPS patients, PR is infrequently utilized. Despite the increased prevalence of multiple risk factors, PR patients do not have an increased 30-day postoperative M + M.

Retroperitoneal sarcomas- a challenging problem

Retroperitoneal sarcomas are relatively rare tumours and usually present in a locally advanced stage. Liposarcoma is the most common histopathology. If operable, surgery is the treatment of choice. The role of adjuvant chemotherapy or radiotherapy is not yet defined. Advanced cases are treated by chemotherapy. The prognosis is poor in patients with positive resection margins, high-grade tumours and recurrent tumours.

Overcoming evasive resistance from vascular endothelial growth factor a inhibition in sarcomas by genetic or pharmacologic targeting of hypoxia-inducible factor 1α

Increased levels of hypoxia and hypoxia-inducible factor 1α (HIF-1α) in human sarcomas correlate with tumor progression and radiation resistance. Prolonged antiangiogenic therapy of tumors not only delays tumor growth but may also increase hypoxia and HIF-1α activity. In our recent clinical trial, treatment with the vascular endothelial growth factor A (VEGF-A) antibody, bevacizumab, followed by a combination of bevacizumab and radiation led to near complete necrosis in nearly half of sarcomas. Gene Set Enrichment Analysis of microarrays from pretreatment biopsies found that the Gene Ontology category “Response to hypoxia” was upregulated in poor responders and that the hierarchical clustering based on 140 hypoxia-responsive genes reliably separated poor responders from good responders. The most commonly used chemotherapeutic drug for sarcomas, doxorubicin (Dox), was recently found to block HIF-1α binding to DNA at low metronomic doses. In four sarcoma cell lines, HIF-1α shRNA or Dox at low concentrations blocked HIF-1α induction of VEGF-A by 84–97% and carbonic anhydrase 9 by 83–93%. HT1080 sarcoma xenografts had increased hypoxia and/or HIF-1α activity with increasing tumor size and with anti-VEGF receptor antibody (DC101) treatment. Combining DC101 with HIF-1α shRNA or metronomic Dox had a synergistic effect in suppressing growth of HT1080 xenografts, at least in part via induction of tumor endothelial cell apoptosis. In conclusion, sarcomas respond to increased hypoxia by expressing HIF-1α target genes that may promote resistance to antiangiogenic and other therapies. HIF-1α inhibition blocks this evasive resistance and augments destruction of the tumor vasculature.

Phase II study of neoadjuvant bevacizumab and radiotherapy for resectable soft tissue sarcomas

PURPOSE

Numerous preclinical studies have demonstrated that angiogenesis inhibitors can increase the efficacy of radiotherapy (RT). We sought to examine the safety and efficacy of bevacizumab (BV) and RT in soft tissue sarcomas and explore biomarkers to help determine the treatment response.

METHODS AND MATERIALS

Patients with ≥5 cm, intermediate- or high-grade soft tissue sarcomas at significant risk of local recurrence received neoadjuvant BV alone followed by BV plus RT before surgical resection. Correlative science studies included analysis of the serial blood and tumor samples and serial perfusion computed tomography scans.

RESULTS

The 20 patients had a median tumor size of 8.25 cm, with 13 extremity, 1 trunk, and 6 retroperitoneal/pelvis tumors. The neoadjuvant treatment was well tolerated, with only 4 patients having Grade 3 toxicities (hypertension, liver function test elevation). BV plus RT resulted in ≥80% pathologic necrosis in 9 (45%) of 20 tumors, more than double the historical rate seen with RT alone. Three patients had a complete pathologic response. The median microvessel density decreased 53% after BV alone (p <.05). After combination therapy, the median tumor cell proliferation decreased by 73%, apoptosis increased 10.4-fold, and the blood flow, blood volume, and permeability surface area decreased by 62-72% (p <.05). Analysis of gene expression microarrays of untreated tumors identified a 24-gene signature for treatment response. The microvessel density and circulating progenitor cells at baseline and the reduction in microvessel density and plasma soluble c-KIT with BV therapy also correlated with a good pathologic response (p <.05). After a median follow-up of 20 months, only 1 patient had developed local recurrence.

CONCLUSIONS

The results from the present exploratory study indicated that BV increases the efficacy of RT against soft tissue sarcomas and might reduce the incidence of local recurrence. Thus, this regimen warrants additional investigation. Gene expression profiles and other tissue and circulating biomarkers showed promising correlations with treatment response.

Retroperitoneal soft tissue sarcomas: experience at a single institution in Mexico

BACKGROUND

Retroperitoneal soft tissue sarcomas (RSTS) are a rare and uncommon entity with a poor 5-year overall survival (OS) of approximately 50%, even though they rarely metastasize. The aim of the present study was to analyze the survival of patients with RSTS treated at our institution.

PATIENTS AND METHODS

Patients with RSTS treated between 1990 and 2008 were included. Variables analyzed were age, sex, histological type, TNM stage, tumor size, grade of differentiation, and treatment (surgery, chemotherapy only, radiotherapy only, adjuvant radiotherapy, and best supportive care). R0, R1, and R2 resection were analyzed. Overall survival, recurrence-free survival (RFS), cancer-specific survival (CSS), and survival comparison by stage, grade, and type of resection were analyzed.

RESULTS

Data for 46 patients were analyzed, 20 men and 26 women. Median age was 51.1 years. Surgery with a curative intent was performed in 32 patients, and R0 resection was feasible in 19 (59.4%). The 5- and 10-year OS rates were 47 and 30%, respectively, for the entire group. The median CSS for resected patients was 102 months; the 5-year OS for stages I, III, and IV was 83, 37, and 0%, respectively; the 5-year OS for low histological grade disease and high histological grade disease was 82 and 35%, respectively; and for R0, R1, and R2 resection, the 5-year OS was 81, 56, and 14%, respectively. Median RFS was 79 months.

CONCLUSIONS

Incomplete surgical resection, unresectable disease, high histological grade, and advanced TNM stage are associated with a poor survival in patients with RSTS. Complete resection is still the treatment of choice.

Current concepts and future perspectives in retroperitoneal soft-tissue sarcoma management

Retroperitoneal soft-tissue sarcomas are complex, heterogeneous cancers requiring expert multidisciplinary care. They can occur anywhere in the retroperitoneal abdominal or pelvic space. Usually large at presentation they present particular challenges for both local treatment and systemic control. The most common adult subtypes are liposarcomas and leiomyosarcomas, followed by pleomorphic sarcoma/malignant fibros histiocytoma (an entity not always easily distinguishable from dedifferentiated liposarcoma). A variety of additional histotypes may also be observed, but are uncommon in the retroperitoneum, either because of intrinsic rarity or because they are usually found in other anatomic sites. The underlying biology varies according to the different histotypes. Pediatric subtypes mainly comprise extraskeletal Ewing sarcoma/pPNET and alveolar rhabdomyosarcoma. Surgery is critical for controlling these tumors and requires an aggressive approach. It may also provide useful palliation for patients with advanced slow-growing disease. Radiotherapy has acquired a definite position in attempting to reduce relapse, although prospective trials of adjuvant or neoadjuvant radiotherapy are needed. Chemotherapy has a limited role in the adjuvant setting for most forms of retroperitoneal sarcoma (excluding pediatric subtypes), but has an increasing role in advanced disease. Novel targeted therapeutic agents that target specific amplification or translocation products offer promise for subsets of these diseases.

Rare coincidence of familial adenomatous polyposis and a retroperitoneal fibromyxoid sarcoma: report of a case

PURPOSE

Familial adenomatous polyposis is an autosomal-dominant inherited disease with development of as many as thousands of adenomas within colon and rectum. All untreated patients will develop colorectal adenocarcinoma. A variety of extracolonic manifestations can occur, although malignant tumors are rare. An association of familial adenomatous polyposis and sarcomas was reported in a few cases only.

METHODS

We present the exceptional case of a 24-year-old male with genetically verified familial adenomatous polyposis (deletion of 10 base pairs at position 228-237 of exon 15A). The patient underwent prophylactic subtotal proctocolectomy and ileal-pouch rectal anastomosis in 2003. Two years later, an obstruction of the left ureter caused by a retroperitoneal mass was diagnosed.

RESULTS

Histopathologic findings after complete tumor resection showed a low-grade fibromyxoid sarcoma. CT scan and clinical follow-up through 15 months postoperatively revealed no recurrent tumor growth.

CONCLUSIONS

To our knowledge, this is the first reported case of familial adenomatous polyposis with metachronous retroperitoneal fibromyxoid sarcoma. Proctocolectomy or total colectomy and complete tumor resection is the treatment of choice in this case. In addition to more common semimalignant retroperitoneal desmoid tumors in familial adenomatous polyposis patients, a malignant soft-tissue tumor also has to be considered for differential diagnosis.

[Retroperitoneal sarcomas. Report of five new cases and review of the current situation]

INTRODUCTION

Soft-tissue sarcomas represent a heterogeneous group of rare tumors arising from the mesenchymal cells of the connective tissue. Approximately 15% of these tumors arise in the retroperitoneum. These neoplasms are locally aggressive and the only curative treatment is surgical resection "en-bloc". The main cause of mortality is locoregional recurrence. Five-year survival is 3-58%, depending on the histologic subtype and grade.

PATIENTS AND METHOD

Over a 5-year period (2001 to 2006), we performed surgery in five patients with retroperitoneal sarcomas. The mean age was 59 years (range, 46-76) with a male-to-female ratio of 3:2. The most frequent signs were abdominal pain and the appearance of a mass. In 2 patients, an incidental diagnosis was made during the surgical intervention.

RESULTS

Surgical resection was performed in 5 patients but was incomplete in two patients. We removed 2 liposarcomas, 1 leiomyosarcoma, 1 chondrosarcoma and 1 fusocellular sarcoma arising in the kidney. Locoregional recurrence occurred in four patients, requiring between 1 and 2 new relaparotomies (using the retroperitoneal approach in 2 patients). There was one death.

CONCLUSIONS

Retroperitoneal sarcomas are a heterogeneous group of tumors, in which the only common factor is the anatomical location. New randomized, prospective, multicenter trials are required to apply different therapeutic options according to the subtype of retroperitoneal sarcoma.

Local Management of Adult Soft Tissue Sarcomas

Soft tissue sarcomas (STS) are rare tumors classified into multiple histological subtypes and categorized into four sites: extremity and trunk, head and neck, retroperitoneal, and visceral, the latter now predominantly consisting of gastrointestinal stromal tumors. Well-planned, complete surgical resection is the mainstay of curative therapy for tumors at each of these sites. The success of surgery alone in controlling disease varies with the site, histologic grade, depth, and size of the tumor. For high-risk tumors, adjuvant therapy should be considered. In high-risk extremity tumors, adjuvant radiation has been proven in randomized trials to improve local control. Limb-sparing surgery combined with adjuvant radiation achieves equivalent local control to amputation, with the same distant relapse-free survival. Due to anatomical constraints, tumors of the head and neck and retroperitoneum are typically excised with close margins, providing a rationale for adjuvant radiation; the available evidence suggests but does not prove a benefit. Large-scale trials of adjuvant imatinib for gastrointestinal stromal tumors are currently being conducted. For tumors of the extremity/trunk, head and neck, and retroperitoneum, biopsy prior to definitive resection is recommended to establish the diagnosis and permit intelligent treatment planning with appropriate choice and sequencing of adjuvant therapies. This planning is most expeditiously done through multidisciplinary consultation at an experienced sarcoma center.

Intensity modulated radiation-therapy for preoperative posterior abdominal wall irradiation of retroperitoneal liposarcomas

PURPOSE

Preoperative external-beam radiation therapy (preop RT) in the management of Retroperitoneal Liposarcomas (RPLS) typically involves the delivery of radiation to the entire tumor mass: yet this may not be necessary. The purpose of this study is to evaluate a new strategy of preop RT for RPLS in which the target volume is limited to the contact area between the tumoral mass and the posterior abdominal wall.

METHODS AND MATERIALS

Between June 2000 and Jan 2005, 18 patients with the diagnosis of RPLS have been treated following a pilot protocol of pre-op RT, 50 Gy in 25 fractions of 2 Gy/day. The Clinical Target Volume (CTV) has been limited to the posterior abdominal wall, region at higher risk for local relapse. A Three-Dimensional conformal (3D-CRT) and an Intensity Modulated (IMRT) plan were generated and compared; toxicity was reported following the National Cancer Institute (NCI) Common Terminology Criteria for Adverse Events v3.0.

RESULTS

All patients completed the planned treatment and the acute toxicity was tolerable: 2 patients experienced Grade 3 and 1 Grade 2 anorexia while 2 patients developed Grade 2 nausea. IMRT allows a better sparing of the ipsilateral and the contralateral kidney. All tumors were successfully resected without major complications. At a median follow-up of 27 months 2 patients developed a local relapse and 1 lung metastasis.

CONCLUSIONS

Our strategy of preop RT is feasible and well tolerated: the rate of resectability is not compromised by limiting the preop CTV to the posterior abdominal wall and a better critical-structures sparing is obtained with IMRT.

Vascular reconstruction with the superficial femoral vein following major oncologic resection

INTRODUCTION

Involvement of critical vascular structures has historically been considered a contraindication to tumor resection. This study describes outcomes following radical oncologic resection with concomitant resection of critical vascular structures and reconstruction with the superficial femoral vein (SFV).

METHODS

All patients undergoing radical oncologic resection requiring resection of major vascular structures and concomitant reconstruction using the SFV as conduit were retrospectively reviewed. Primary outcomes were surgical morbidity and mortality; secondary measures included long-term patency and oncologic outcomes.

RESULTS

Seven patients were included. There were three retroperitoneal and two groin sarcomas, and two squamous cell carcinomas metastatic to groin lymph nodes. No perioperative mortality occurred. Five patients experienced minor morbidity. One vein graft in a patient with pre-existing chronic deep venous thrombosis (DVT) occluded post-operatively. No subsequent long-term venous or arterial graft occlusions occurred (median 20.2 months, range 9.0-49.7). Two patients died of tumor recurrence during follow-up.

CONCLUSIONS

Resection of tumors involving critical vascular structures is feasible. The SFV conduit is a versatile option for major vascular reconstruction, providing good long-term patency rates with acceptable morbidity and mortality. Vascular resection and reconstruction with the SFV offers another technique to provide limb-sparing surgery in patients traditionally offered only amputation, while providing favorable oncologic outcomes.

Use of Tissue Expanders and Pre-operative External Beam Radiotherapy in the Treatment of Retroperitoneal Sarcoma

INTRODUCTION

We report our experience of treating retroperitoneal sarcoma (RPS) using pre-operative external beam radiotherapy (EBRT) in combination with radical resectional surgery from 1990 to 2005.

METHODS

Twenty-eight primary and 10 recurrent tumors were identified from a prospective database.

RESULTS

The resection rate was 71% overall; 82% in primary (23/28) and 40% (4/10) in recurrent cases. EBRT was administered preoperatively in 25 patients, postoperatively in 1, and palliatively in 11. In 33 patients a saline-filled tissue expander was inserted into the abdomen before radiotherapy to displace small bowel from the radiation field. 4,500-5,000 cGy was administered in fractions of 180-200 cGy over a 5-week period; surgery followed 6-8 weeks later. Expander insertion was associated with minimal morbidity; 31/37 patients received a dose of 4,000 cGy or more (median 4,650 cGy). Median resected tumor diameter was 13 cm, and a median of three adjacent organs was resected per patient. Complete macroscopic resection was achieved in 25/27 patients (93%); R0 in 9 (33%) and R1 in 13 (48%) (microscopic margins unclear in 5). There was no postoperative mortality. Tumors were high-grade in 20 patients, low-grade in 14 and ungraded in 4. Actuarial 5- and 10-year survival for all patients was 74 and 60%. For operable primary tumors, the 5-year survival and disease-free rates were 90 and 80%. In four patients with operable recurrent tumors, median disease-free interval was 91 months (27-160). In the 11 inoperable cases, median survival after radiotherapy was 48 months (9-77).

CONCLUSIONS

We conclude that a combination of pre-operative tissue expander placement, high-dose EBRT and radical resectional surgery can achieve acceptable morbidity, extended survival and low long-term recurrence in patients with RPS.

STATISTICS

Median (interquartile range).

Long-term results of two prospective trials of preoperative external beam radiotherapy for localized intermediate- or high-grade retroperitoneal soft tissue sarcoma

BACKGROUND

The reported data on surgery plus radiotherapy for retroperitoneal soft tissue sarcomas (RPS) have been mostly from retrospective studies. We evaluated the long-term outcome of patients with operable RPS who were treated with protocol-based preoperative radiotherapy followed by complete surgical resection.

METHODS

Data from two prospective trials that included preoperative radiotherapy and surgery for patients with radiographically resectable RPS were combined to define long-term relapse rates and survival.

RESULTS

Seventy-two patients with intermediate- or high-grade RPS were treated with preoperative radiotherapy (median dose, 45 Gy; range, 18.0-50.4 Gy). Fifty-four patients (75%) had primary RPS, whereas 18 (25%) had recurrent disease. The median tumor size was 15.5 cm. Sixty-four patients completed the planned preoperative radiotherapy; 57 (89%) underwent laparotomy with curative intent, and 54 (95%) had a macroscopically complete (R0 or R1) resection. With a median follow-up of 40.3 months, 28 patients (52%) who received preoperative radiotherapy and underwent a macroscopically complete resection had recurrences. For the 54 patients who underwent R0 or R1 resection after preoperative radiotherapy, the 5-year local recurrence-free, disease-free, and overall survival rates were 60%, 46%, and 61%, respectively. The median overall survival has not been reached (>60 months).

CONCLUSIONS

Patients with intermediate- or high-grade RPS treated with preoperative radiotherapy plus complete resection had a median survival >60 months. This compares favorably to historical data for similar patients treated with surgery alone.

Adult soft tissue sarcomas: Conventional therapies and molecularly targeted approaches

The therapeutic approach to soft tissue sarcomas (STS) has evolved over the past two decades based on the results from randomized controlled trials, which are guiding physicians in the treatment decision-making process. Despite significant improvements in the control of local disease, a significant number of patients ultimately die of recurrent/metastatic disease following radical surgery due to a lack of effective adjuvant treatments. In addition, the characteristic chemoresistance of STS has compromised the therapeutic value of conventional antineoplastic agents in cases of unresectable advanced/metastatic disease. Therefore, novel therapeutic strategies are urgently needed to improve the prognosis of patients with STS. Recent advances in STS biology are paving the way to the development of molecularly targeted therapeutic strategies, the efficacy of which relies not only on the knowledge of the molecular mechanisms underlying cancer development/progression but also on the personalization of the therapeutic regimen according to the molecular features of individual tumours. In this work, we review the state-of-the-art of conventional treatments for STS and summarize the most promising findings in the development of molecularly targeted therapeutic approaches.

Adjuvant Radiation Therapy for Resectable Retroperitoneal Soft Tissue Sarcoma

BACKGROUND

In the management of retroperitoneal sarcomas it is necessary to achieve local control to ensure survival. The role of adjuvant radiation therapy (RT), either pre- or postoperative, remains controversial.

METHODS

Outcomes for 40 patients with retroperitoneal sarcoma treated with surgery and postoperative RT (n = 25) or preoperative RT (n = 15) were analyzed for variables prognostic for local control, survival, and associated complications.

RESULTS

Patterns of failure for patients treated by resection and postoperative RT were local (n = 4), local and distant (n = 3), and distant (n = 3). The failure patterns for preoperative RT cases were local (n = 2), local and distant (n = 2); and distant (n = 4). Median time to local recurrence in the postoperative and preoperative RT series were 1 year and 2.5 years respectively. The margin status was predictive for local control (P = 0.0065) and survival (P = 0.0012), regardless of treatment sequence. Absolute 5-year survival was 12% with positive margins versus 69% if negative. Histologic grade was indicative of the risk for distant metastasis (low grade 8% vs high grade 64%; P = 0.1373), and significantly predicted 5-year absolute survival (low grade 77% vs high grade 34%; P = 0.0267). Postoperative RT was associated with significant complications (infection, hemorrhage, and bowel obstruction--2 cases each).

CONCLUSION

Compared with the surgery-alone series, adjuvant RT appears to improve the probability of local control. Preoperative RT may be the preferred sequence potentially to improve tumor resectability and local-regional control with less risk of complications than with postoperative RT.

Therapeutisches Management intraabdomineller und retroperitonealer Weichgewebssarkome

In this article, we review the diagnostics, therapy, follow-up, and prognosis of intra-abdominal and retroperitoneal soft tissue sarcomas. There are descriptions and discussion of the surgical techniques, advantages and disadvantages of various types and combinations of adjuvant and neoadjuvant therapies, therapy in case of nonresectability, and procedures for desmoid tumors. Further, treatment results, control methods, and studies on new therapeutic approaches are presented.

Adriamycin and cis-platinum as first-line treatment in unresectable locally advanced or metastatic adult soft-tissue sarcomas

Standard chemotherapy in advanced adult soft-tissue sarcomas (STS) has not yet been established. We evaluated the efficacy and toxicity of the combination of adriamycin (ADR) and cis-platinum (CDDP) as first-line treatment in nonoperable locally advanced or metastatic adult STS. Thirty patients were treated with CDDP 100 mg/m2 on day 1 and ADR 75 mg/m2 equally divided on days 1 to 3, every 3 weeks for 6 cycles. Patients were evaluated for response, toxicity, and survival, while resectability of residual disease was also assessed after the third cycle and the end of chemotherapy. No complete response was observed. Five patients (16.7%, 95% CI: 2.5%-31%) achieved partial response, 16 patients (53.3%, 95% CI: 34%-72%) had stable disease and 9 patients (30%, 95% CI: 13%-47%) had progressive disease. The overall median survival was 11.5 months (range, 4-96 months), and the median time to disease progression was 6 months (range, 0-96 months). Furthermore, two patients with PR and six patients with stable disease underwent further surgery followed by radiotherapy in four of them. At present, 5 patients remain free of relapse for 96, 90, 72, 60, and 48 months, respectively. Treatment-related toxicity was acceptable, with moderate myelosuppression and alopecia as the main adverse events. The ADR/CDDP regimen was well tolerated, but it did not achieve a high response rate. However, patients with resectable disease after chemotherapy achieved long-term survival. Further studies are needed to evaluate the role of combined-modality treatments in the management of patients with advanced STS.

Phase I trial of preoperative concurrent doxorubicin and radiation therapy, surgical resection, and intraoperative electron-beam radiation therapy for patients with localized retroperitoneal sarcoma

PURPOSE

The primary objective of this phase I trial was to define the maximum-tolerated dose of external-beam radiation with concurrent fixed-dose continuous-infusion doxorubicin followed by surgical resection and electron-beam intraoperative radiation therapy (EB-IORT) for patients with localized, potentially resectable retroperitoneal sarcomas (RPS).

PATIENTS AND METHODS

Thirty-five patients with radiographically resectable primary or recurrent intermediate- or high-grade RPS were treated. Doxorubicin was administered each week for 4 or 5 weeks as an initial bolus (4 mg/m2) followed by a 4-day continuous infusion (4 mg/m2/d). Concurrent radiation therapy was administered in escalating doses of 18.0, 30.6, 36.0, 41.4, 46.8, or 50.4 Gy in 1.8-Gy fractions. Radiographic restaging was performed 4 to 8 weeks after chemoradiation, and patients with localized disease underwent surgical resection with EB-IORT (15 Gy).

RESULTS

Chemoradiation was completed as outpatient therapy in 31 patients (89%); four patients required hospital admission during chemoradiation or in the postchemoradiation preoperative period. At the highest radiation dose of 50.4 Gy, two (18%) of 11 patients had grade 3 or 4 nausea. Twenty-nine patients (83%) underwent laparotomy; six patients had interval disease progression and did not undergo surgery. Grossly complete resection (R0 or R1) was performed in 26 (90%) of 29 patients who had surgery. EB-IORT was feasible and successfully administered to 22 patients who had R0 or R1 resections.

CONCLUSION

Preoperative chemoradiation, surgical resection, and EB-IORT are feasible for patients with RPS. Preoperative external-beam radiation can be administered to a total dose of 50.4 Gy with continuous-infusion doxorubicin.

Recent advances in radiotherapy for soft-tissue sarcoma

The use of radiotherapy in soft-tissue sarcoma continues to evolve. This review focuses on how current management is influenced by the most recent publications in the field. In particular, experience of patients treated without radiotherapy permits guidelines to be established that define a subset of patients who do not need radiotherapy to achieve sarcoma cure with good function. Strategies for radiotherapy delivery are discussed, including the most recent prospective results from a trial of preoperative and postoperative radiotherapy, with particular emphasis on randomized data. Also, the definitions for adequacy of surgical excision and the ability to achieve high rates of local control when margins are minimally positive are integrated into a planned approach. The difficult problem of retroperitoneal sarcoma is discussed, as are chemoradiotherapy protocols that may enhance local and systemic outcome. Finally, the potential for image-guided radiotherapy, enhanced targeting, and better radiotherapy delivery in the contemporary era is addressed.