Histologic Type Predicts Survival in Patients with Retroperitoneal Soft Tissue Sarcoma

Retroperitoneal sarcoma: a 10-year follow-up analysis using hospital-based cancer registry data in Japan

OBJECTIVES

We sought clinical characteristics, survival outcomes, and prognostic factors for overall survival of retroperitoneal sarcoma in Japan.

METHODS

A Japanese hospital-based cancer registry database with a pivotal 10-year follow-up was used to identify and enroll patients, registered from 106 institutions, diagnosed with retroperitoneal sarcoma in 2008-2009. Treating hospitals were divided by hospital care volume; high-volume hospitals and low-volume hospitals were defined as ≥ 4 and < 4 cases/year, respectively.

RESULTS

A total of 91 men and 97 women were included, with a median age of 64 years. The most common histological type was liposarcoma in 101 patients, followed by leiomyosarcoma in 38 patients. The 5-year and 10-year overall survival rates were 44.1 and 28.3%. The majority of patients (n = 152, 80.9%) were treated at low-volume hospitals. High-volume hospital patients had higher 10-year overall survival rates than low-volume hospital patients (51.2% vs 23.2%, P = 0.026). Multivariate analysis revealed age over 60 years, treatment in low-volume hospitals and chemotherapy were independent predictors of unfavorable survival while treatment with surgery was an independent predictor of favorable survival.

CONCLUSIONS

The possibility of surgical removal was suggested to be the most important prognostic factor for retroperitoneal sarcoma. Better survival was shown in patients treated at high-volume hospitals in our series.

Progress in Retroperitoneal Sarcoma Management: Surgical and Radiotherapy Approaches

Surgical resection is the cornerstone of curative treatment for retroperitoneal sarcomas (RPS), aiming for complete excision, yet the complexity of RPS with its proximity to vital structures continues to lead to high local recurrence rates after surgery alone. Thus, the role of radiotherapy (RT) continues to be refined to improve local control, which remains an important goal to prevent RPS recurrence. The recently completed global randomized trial to evaluate the role of surgery with and without preoperative RT - STRASS1, did not demonstrate a significant overall benefit for neoadjuvant RT based on the pre-specified definition of abdominal recurrence-free survival, however, sensitivity analysis using a standard definition of local recurrence and analysis of outcomes by compliance to the RT protocol suggests histology-specific benefit in well- and some de-differentiated liposarcomas. Ultimately, multidisciplinary collaboration and personalized approaches that consider histological sarcoma types and patient-specific factors are imperative for optimizing the therapeutic strategy in the management of RPS.

Inferior vena cava resection for a leiomyosarcoma: A case report

INTRODUCTION AND IMPORTANCE

Leiomyosarcomas of the inferior vena cava are scarce. Surgery is the only potential curative treatment. Such a surgery is complex and technically demanding, requiring a huge experience in both visceral and vascular surgery. Indeed, enlarged visceral resection may be needed to achieve a free tumor margins as the tumor may invade the duodenum, the head of the pancreas and the liver. Moreover, vascular reconstruction is mandatory which might be complex as both venal reins are usually invaded by the tumor like in our case below.

CASE PRESENTATION

A 53-year-old woman presented with abdominal vague pain. Imaging consisting in abdominal CT-scan with contrast and magnetic resonance angiography were suggestive of the diagnosis of leiomyosarcoma of the inferior vena cava. A surgical complete resection with free margins was conducted. A primary repair of the inferior vena cava and the right renal vein walls. End-to-side anastomosis with a polytetrafluorethylene (PTFE) prosthesis was mandatory to reconstruct the renal left vein to the inferior vena cava. Postoperative outcomes were uneventful. Pathology examination confirmed the diagnosis.

DISCUSSION

The optimal management of leiomyosarcoma of inferior vena cava is controversial. Surgery remains the cornerstone of treatment. However, not all patients are qualified for surgical resection. The prognosis depends on the early diagnosis and histology type.

CONCLUSION

The management of leiomyosarcomas of inferior vena cava requires a multidisciplinary consensus involving experienced surgery and oncology teams.

Role of Radiation Therapy in Retroperitoneal Sarcoma

Retroperitoneal sarcoma comprises a small subset of all soft tissue sarcoma and includes various histopathologic subtypes, each with unique patterns of behavior and differential risks for local recurrence and hematogenous metastatic spread. The primary treatment modality is surgery, although even with complete macroscopic resection, recurrence is common. The rationale for the addition of radiotherapy to resection is to improve local control; however, the use of radiation therapy for retroperitoneal sarcoma is controversial, and existing data are suboptimal to guide management. Treatment decisions should be determined with multidisciplinary input and shared decision-making. When used in selected patients, radiation therapy should be delivered preoperatively; postoperative treatment is not recommended.

[Differentiated surgical approach for retroperitoneal non-organ liposarcoma]

OBJECTIVE

To determine the indications for combined and organ-sparing surgery depending on malignancy grade of retroperitoneal liposarcoma.

MATERIAL AND METHODS

A retrospective study included 190 patients with retroperitoneal liposarcoma. Influence of malignancy grade, lesion of adjacent organs and resection/excision of adjacent organs on the overall and recurrence-free survival was studied. Moreover, we analyzed the issue of kidney-sparing surgery and nephrectomy.

RESULTS

Overall and recurrence-free survival were significantly worse in high grade (G2-3) compared to low-grade tumors (G1) (p=0.0001; log-rank test). Visceral invasion was revealed in 23% of patients with low-grade (G1) tumors and 53% of patients with high-grade (G2-3) neoplasms. Visceral invasion significantly impairs overall and recurrence-free survival in both low grade (G1) and high-grade (G2-3) tumors (p=0.0001; log-rank test). In case of low grade (G1) retroperitoneal liposarcoma, overall and recurrence-free survival was similar after combined surgery without histologically confirmed visceral invasion of liposarcoma and organ-sparing surgery (p=0.006; p=0.053; log-rank test). On the contrary, high grade (G2-3) tumor was followed by significantly better overall and recurrence-free survival after combined surgery without histologically confirmed visceral invasion compared to organ-sparing surgery (p=0.006; p=0.053; log-rank test). Recurrence-free survival was similar after kidney-sparing surgery and nephrectomy among patients with low-grade (G1) tumor (p=0.456; log-rank test). In case of high-grade retroperitoneal liposarcoma (G2-3), recurrence-free survival was significantly worse after kidney-sparing surgery compared to nephrectomy (p=0.039; log-rank test).

CONCLUSION

Surgery is the only potentially radical treatment of patients with retroperitoneal liposarcoma. Organ-sparing including kidney-sparing surgery is advisable for low-grade liposarcoma (G1). On the contrary, organ-sparing surgery impairs long-term results and prognosis in patients with high-grade tumors (G2-3). Combined operations including nephrectomy are justified for high-grade retroperitoneal liposarcoma (G2-3).

The role of 18 F-FDG PET/CT in retroperitoneal sarcomas-A multicenter retrospective study

BACKGROUND

The role of ¹⁸ F-fluorodeoxyglucose positron emission tomography/computed tomography (¹⁸ F-FDG PET/CT) in the evaluation of retroperitoneal sarcomas is poorly defined. We evaluated the correlation of maximum standardized uptake value (SUVmax) with pathologic tumor grade in the surgical specimen of primary retroperitoneal dedifferentiated liposarcoma (DDLPS) and leiomyosarcoma (LMS).

METHODS

Patients with the above histological subtypes in three participating institutions with preoperative ¹⁸ F-FDG PET/CT scan and histopathological specimen available for review were included. The association between SUVmax and pathological grade was assessed. Correlation between SUVmax and relapse-free survival (RFS) and overall survival (OS) were also studied.

RESULTS

Of the total 58 patients, final pathological subtype was DDLPS in 44 (75.9%) patients and LMS in 14 (24.1%) patients. The mean SUVmax was 8.7 with a median 7.1 (range, 2.2-33.9). The tumors were graded I, II, III in 6 (10.3%), 35 (60.3%), and 17 (29.3%) patients, respectively. There was an association of higher histological grade with higher SUVmax (r_s  = 0.40, p = .002). Increasing SUVmax was associated with worse RFS (p = .003) and OS (p = .003).

CONCLUSION

There is a correlation between SUVmax and pathologic tumor grade; increasing SUVmax was associated with worse OS and RFS, providing a preoperative noninvasive surrogate marker of tumor grade and biological behavior.

Leiomyosarcoma of the inferior vena cava: a case report

Leiomyosarcoma (LMS) of the inferior vena cava (IVC) is an extremely rare malignancy with <400 cases reported. We present a 42-year-old woman with a 3-day history of vague and non-specific abdominal pain. Examination revealed mild tenderness to the epigastrium and right upper quadrant with no other findings. Abdominal ultrasound was performed, which revealed a large hypoechoic mass overlying the IVC. Abdominal computed tomography (CT) was performed which revealed an 8.9 × 7.9 × 9 cm multilobulated lesion encasing the IVC. A CT-guided biopsy was performed which revealed a primary LMS of the IVC. Surgical en bloc excision was performed with an end-to-end Dacron graft for IVC reconstruction. Histopathology confirmed LMS of the vessel wall with negative surgical margins.

Integrative assessment of clinicopathological parameters and the expression of PD-L1, PD-L2 and PD-1 in tumor cells of retroperitoneal sarcoma

Evidence is limited regarding the immunologic profile and immune microenvironment of soft tissue sarcoma subtypes. The aim of the present study was to describe the clinical significance and prognostic implications of PD-L1, PD-L2, and PD-1 in patients with retroperitoneal sarcoma (RSar). In this retrospective, multicenter, collaborative study, medical charts were reviewed and the immunohistochemical staining results of resected tissue specimens from 51 patients with RSar were examined. Immunohistochemical staining was performed with primary antibodies against PD-L1, PD-L2, PD-1, and Ki-67. The correlations between the baseline clinical parameters and expression levels of the four molecules in sarcoma cells were evaluated, and their prognostic values after tumor resection were assessed. Dedifferentiated liposarcoma (41%), leiomyosarcoma (20%), and undifferentiated pleomorphic sarcoma (16%) were the three major types identified. Dedifferentiated liposarcoma and leiomyosarcoma showed higher levels of PD-L1 expression than did other sarcomas. The Spearman correlation analysis revealed that baseline serum lactate dehydrogenase levels were moderately and positively correlated with PD-L1 (P=0.02, r=0.41) and PD-L2 (P=0.006, r=0.47) expression. The median recurrence-free and disease-specific survival was 58 and 16 months, respectively, during the 29-month median follow-up after surgery. On univariate analysis, a higher expression level of PD-1 was associated with a higher risk of recurrence, whereas multivariate analyses revealed that independent predictors of recurrence-free and disease-specific survival indicated a high expression of Ki-67 (P=0.03; hazard ratio, 2.29 vs. low expression) and prognostic stage IIIB (P=0.04; hazard ratio, 5.11 vs. stage I-II), respectively. Findings of the current study provide novel insights about the prognostic value of PD-L1, PD-L2, and PD-1 expression in RSar. Serum lactate dehydrogenase levels constitute a potential predictor of PD-L1 and PD-L2 expression levels in RSar. Further investigations are needed to determine the immunologic landscape of RSar and provide a foundation for therapeutic intervention using immune checkpoint inhibitors.

Epidemiology and survival of liposarcoma and its subtypes: A dual database analysis

PURPOSE

Liposarcoma (LPS) is a one of the most commonly diagnosed soft tissue sarcomas. Little is known about the epidemiology and prognosis of each subtype. We present an analysis of epidemiology and survival of the subtypes of LPS using a national database.

METHODS

We queried the Survival Epidemiology, and End Results (SEER) and the Canadian Institute for Clinical Evaluative Sciences (ICES) databases for data on 7 types of LPS. Pearson's chi square was used to determine associations between variables and subtypes. Kaplan-Meier and Cox Regression analyses were performed for two tests: one using SEER data and the other using variables common to both SEER and ICES.

RESULTS

The well-differentiated subtype was the most common subtype identified. Metastatic disease was associated with decreased survival across all subtypes and age >35 was associated with decreased survival in well-differentiated and myxoid subtypes. Tumor grade was associated with decreased survival in the well-differentiated, myxoid, mixed, and round cell subtypes. In the secondary analysis, age >35 was associated with decreased survival in the myxoid subtype.

CONCLUSIONS

The prognosis of liposarcoma differs greatly by subtype. Clinicians should account for patient factors at the time of diagnosis to best navigate treatment of their patients.

Malignant fibrous neoplasms of long bones: analysis of the surveillance, epidemiology, and end results database from 1973 to 2015

BACKGROUND

Malignant fibrous neoplasms (MFN) of long bones are rare lesions. Moreover, the prognostic determinants of MFN of long bones have not been reported. This study aimed to present epidemiological data and analyse the prognostic factors for survival in patients with MFN.

MATERIALS AND METHODS

The Surveillance, Epidemiology, and End Results (SEER) programme database was used to screen patients with malignant fibrous neoplasms (MFN) of long bones from 1973 to 2015, with attention to fibrosarcoma, fibromyxosarcoma, periosteal fibrosarcoma and malignant fibrous histiocytoma. The prognostic values of overall survival (OS) and cancer-specific survival (CSS) were assessed using the Cox proportional hazards regression model with univariate and multivariate analyses. The Kaplan-Meier method was used to obtain OS and CSS curves.

RESULTS

A total of 237 cases were selected from the SEER database. Malignant fibrous histiocytoma was the most common form of lesion in long bones. Multivariate analysis revealed that independent predictors of OS included age, stage, tumour size and surgery. Age, stage, tumour size and surgery were also independent predictors of CSS. Additionally, the most significant prognostic factor was whether metastasis had occurred at the time of initial diagnosis.

CONCLUSION

Among patients with MFN of long bones, age (> 60 years), tumour size (> 10 cm), distant stage, and non-surgical treatment are factors for poor survival.

An Evaluation of the Eighth Edition of the American Joint Committee on Cancer (AJCC) Staging System for Retroperitoneal Sarcomas Using the National Cancer Data Base (NCDB): Does Size Matter?

OBJECTIVES

Retroperitoneal sarcomas (RPS) are often large at diagnosis calling into question the seventh edition AJCC size classification of <5 cm (T1) or ≥5 cm (T2). The eighth edition expands T stage into 4 categories (T1: ≤5 cm, T2: 5<x≤10 cm, T3: 10<x≤15 cm, T4: >15 cm). We evaluated the prognostic ability of the eighth edition using the National Cancer Database (NCDB).

METHODS

Patients with RPS treated between 1998 and 2011 were identified from the NCDB; overall survival (OS) was compared.

RESULTS

Of the 6427 patients identified, 9% had tumors ≤5 cm (n=580), 19.4% 5<x≤10 cm (n=1246), 20.2% 10<x≤15 cm (n=1298) and 47.4% >15 cm (n=3045). With the eighth edition, stage II patients (G2/3 ≤5 cm) have a similar OS to stage IIIA patients (G2/3 5 cm<x≤10 cm), and patients with larger tumors (stage IIIB, G2/3>10 cm) show a decrease in OS. Tumor size as a continuous variable had a modest effect on survival (HR, 1.004; P=0.04). On multivariate analysis, higher T-stage was associated with decreased OS (T4 HR, 1.3; P<0.001) but high grade and incomplete resection (R2) were stronger prognostic factors. The c-index for both editions were similar (80.13 eighth vs. 80.08 seventh).

CONCLUSIONS

The eighth edition AJCC staging system for retroperitoneal sarcoma incorporates larger tumor size parameters that better characterize most patients, but tumor size alone is only a modest predictor of outcome.

The Vanderbilt staging system for retroperitoneal sarcoma: a validation study of 6857 patients from the National Cancer Database

The Vanderbilt staging system for retroperitoneal sarcoma incorporates information regarding the histologic subtype of sarcoma and outperforms the 7th and 8th editions of the AJCC staging systems by several different statistical criteria. The current study was performed using an independent patient cohort from the National Cancer Database (n = 6857) to validate this proposed staging system. Each staging system was assessed for degree of discrimination by pairwise comparisons of adjacent stage categories. Predictive accuracy of 5-year overall survival was performed by comparison of areas under receiver operating characteristic curves generated from logistic regression. Three different concordance indices (Harrell's c, Somers' D, and Gönen and Heller's K) were calculated using bootstrap methods. Amount of variation in observed outcomes explained by each staging system was assessed using O'Quigley's ρ²k and Royston's R². Bayesian information criteria were also assessed as measures of model fit. The revised AJCC 8th edition T categories were not effective in categorizing risk of death. The Vanderbilt staging system showed the best discrimination between adjacent tumor stages, highest predictive accuracy for 5-year overall survival, a higher degree of concordance with and explained variation of clinical outcomes, and resulted in the best fitting regression model. These results obtained with an independent dataset validate the Vanderbilt staging system for retroperitoneal sarcoma and demonstrate its superiority in risk stratification over current and prior editions of the AJCC staging system.

Salvage Surgery for Recurrent Retroperitoneal Well-Differentiated Liposarcoma: Early Reoperation may not Provide Benefit

PURPOSE

Current evidence regarding salvage resection for recurrent retroperitoneal (RP) sarcomas generally lacks detailed histology-specific analyses, but the aggressiveness of these tumors varies widely by histology. We investigated associations between timing and extent of salvage surgery and survival outcomes in patients with recurrent RP well-differentiated liposarcoma (WDLPS).

METHODS

The University of Texas MD Anderson Cancer Center Surgical Oncology sarcoma database was reviewed to identify patients with RP WDLPS who underwent surgical resection for first recurrent disease (salvage surgery) in 1995-2015. Medical records were retrospectively reviewed to identify factors associated with overall survival and disease-free survival.

RESULTS

We identified 52 patients who underwent salvage surgery for RP WDLPS for first local recurrence; 28 (54%) underwent salvage surgery within 6 months after recurrence. Concomitant organ resections were performed in 32 (62%) patients, 4 (13%) of whom had pathologic invasion of resected organs. After R0/R1 resections (n = 45), 38 (84%) experienced a second local recurrence. Multivariable analyses revealed that organ invasion at the primary surgery [hazard ratio (HR) 13.08; p = 0.005] and disease-free interval < 1 year (HR 3.64; p = 0.044) were associated with shorter overall survival. Recurrence-to-salvage interval < 6 months was associated with shorter disease-free survival (HR 2.18; p = 0.025). Concomitant organ resection was associated with a longer hospital stay: ≥ 14 days (odds ratio 21.58; p = 0.007).

CONCLUSIONS

Early salvage surgery may not always be the best approach for recurrent RP WDLPS patients. Because organ invasion is rare among recurrent RP WDLPS patients and concomitant organ resection is associated with a longer hospital stay, preservation of uninvolved organs should be considered.

Surgically Treated Retroperitoneal Sarcoma: A Population-based Competing Risks Analysis

BACKGROUND

Data regarding the relationship between non-disease-specific (NDSM) and disease-specific mortality (DSM) in patients with surgically treated nonmetastatic retroperitoneal sarcoma (nmRPS) are lacking.

OBJECTIVE

To examine the rates of NDSM and DSM among patients with surgically treated nmRPS.

DESIGN, SETTING AND PARTICIPANTS

We used the Surveillance, Epidemiology and End Results (SEER) database (2004-2014) to obtain data for patients with surgically treated nonmetastatic RPS.

OUTCOME MEASUREMENTS AND STATISTICAL ANALYSES

The 5-yr DSM and NDSM rates were generated via competing risks regression (CRR) methodologies. Multivariable CRR models were used to test the effects of age, histologic subtype, grade, size, and radiotherapy (RT) status on NDSM and DSM.

RESULTS AND LIMITATIONS

Overall, 231 (26.8%) and 57 patients (6.7%) died from DSM and NDSM, respectively. Following stratification according to age, histologic subtype, grade, size, and RT status, the proportion of patients who succumbed to NDSM was higher for patients with age above the median, liposarcoma histologic subtype, low grade, and tumor size ≥17cm. DSM rates were also higher among patients with age above the median, leiomyosarcoma histologic subtype, high grade, and tumor size ≥17cm. Multivariable CRR models revealed that age above the median was associated with higher NDSM (hazard ratio [HR]1.7, 95% confidence interval [CI] 1.1-2.7; p=0.019). Conversely, leiomyosarcoma (HR 1.9, 95% CI 1.4-2.6; p<0.0001), sarcoma not otherwise specified (HR 2.4, 95% CI 1.5-3.8; p<0.0001) and other RPS (HR 2, 95% CI 1.2-3.4; p=0.01) histologic subtypes, high grade (HR 3, 95% CI 2.3-4; p<0.0001), and tumor size above the median (HR 1.4, 95% CI 1.1-3.8; p=0.012) were associated with higher DSM. This is a retrospective study and misclassification bias may be present because of the reliability of the distinction between DSM and NDSM.

CONCLUSIONS

The impact of NDSM in surgically treated nmRPS is not trivial, particularly among patients with favorable characteristics such as liposarcoma histologic subtype and low-grade tumors.

PATIENT SUMMARY

Mortality from causes not related to the specific disease is important in patients with retroperitoneal sarcoma (RPS) treated surgically. In particular, patients with good tumor characteristics, namely liposarcoma histologic subtype and low grade, most often do not die from their cancer but succumb to causes other than RPS. Unfortunately, tumor characteristics and radiotherapy administration shed relatively little light on predicting mortality from causes other than cancer in patients with surgically treated RPS. Our report compares the risk of dying from RPS with that of dying from other causes according to the type of surgically treated sarcoma.

Concomitant organ resection does not improve outcomes in primary retroperitoneal well-differentiated liposarcoma: A retrospective cohort study at a major sarcoma center

BACKGROUND

We investigated whether concomitant organ removal as part of the primary resection of RP WDLPS confers an outcome advantage in patients treated at a major sarcoma center.

METHODS

The departmental sarcoma database was reviewed to identify patients with RP WDLPS who underwent initial surgical resection for primary disease at MD Anderson Cancer Center during the study period 1995-2011. We retrospectively reviewed medical records and examined associations between clinicopathologic variables and overall survival (OS) as well as disease-free survival (DFS).

RESULTS

Among 83 patients included in this study, 76 patients (92%) underwent complete resection (R0/R1). Concomitant organ resections were performed in 38 patients (46%). Invasion of the resected organ/s was seen in six patients (7%). Estimated OS was 11.3 years (5-year OS, 86%), and DFS was 5.4 years (5-year DFS, 51%). By multivariate analysis, concomitant organ resection was not associated with improved OS (P = 0.428) or DFS (P = 0.946), and lack of organ resection was associated with a lower risk of postoperative complications (P = 0.01).

CONCLUSIONS

Concomitant organ resection was not associated with a survival benefit in RP WDLPS in this study. In patients with primary RP WDLPS, we recommend selective resection of contiguous organs only if there is clinical suspicion of invasion.

A retrospective, single-center cohort study on 65 patients with primary retroperitoneal liposarcoma

Primary retroperitoneal liposarcoma (PRPLS) is the most common soft tissue malignancy of the retroperitoneum. To determine the pathological features and the curative effects of surgery in patients with PRPLS, and to elucidate key prognostic factors, the present study retrospectively analyzed the clinical cases of 65 patients with PRPLS. Immunohistochemical analysis demonstrated that vimentin and Ki-67 are better indicators for PRPLS immunohistochemical diagnosis compared with S-100 protein. S-100 protein was predominantly expressed in well-differentiated PRPLS. Positive expression of vimentin and Ki-67 were observed in almost all PRPLS samples, and Ki-67 exhibited a higher expression level in high-grade PRPLS. The level of Ki-67 expression was negatively correlated with disease-specific survival (DSS). Survival analysis revealed that the pathological subtype and histological grade were associated with DSS and local recurrence in the patients, whereas the tumor burden was associated with DSS but not local recurrence. In addition, complete tumor resection and contiguous organ resection were able to improve DSS. Microscopically positive margins did not affect DSS, whereas gross margins did. Multivariate analysis revealed that pathological subtype, histological grade and contiguous organ resection were independent prognostic factors, and that histological grade was an independent factor for local recurrence. Patient sex and age at presentation were not independent factors associated with prognosis or local recurrence. Correlation analysis demonstrated that postoperative local recurrence significantly affected DSS, and local recurrence was the most common cause of mortality among patients. Histological grade was strongly associated with the invasion of adjacent organs but not with tumor burden. Furthermore, the tumor burden was not associated with recurrence or tumor invasion of adjacent organs. Ki-67 expression was associated with prognosis. Pathological subtype, histological grade and contiguous organ resection were independent prognostic factors, while histological grade was an independent factor which affected tumor recurrence.

Canine Soft Tissue Sarcomas: Can Being a Dog's Best Friend Help a Child?

Soft tissue sarcomas (STSs) remain a therapeutic challenge for pediatric and adolescent and young adult (AYA) patients. Still today, surgery, radiation therapy, and chemotherapy remain the mainstay of treatment. Obstacles in developing new treatment approaches to improve the outcome are: few patients to enroll in clinical trials, and the diversity of tumor biology between histologic subtypes. Pet dogs may offer an additional strategy to discover and test new therapeutic avenues. The number of dogs diagnosed with a STS each year in the United States is estimated to be around 27,000 to 95,000. In comparison, approximately 900 children less than 20 years old and 1,500 AYAs between 15 and 29 years old are diagnosed with a STS each year in the United States. The mainstay for treatment of STSs in dogs is also surgery, with radiation therapy and chemotherapy when necessary. Similar to what is seen in humans, grade and stage are prognostic in dogs. In one comparative study of the histology and immunohistochemistry of canine STSs, most tumors were diagnosed as the human equivalent of undifferentiated sarcoma, spindle cell sarcoma, or unclassified spindle cell sarcoma. But much work remains to be done to fully assess the validity of canine STSs as a model. Gene expression analysis has been done in a limited number of canine STSs. Tissue banking, development of cell lines, and the ability to mobilize large-scale clinical trials will become essential in veterinary medicine to benefit both dogs and humans.

Recurrence patterns of retroperitoneal leiomyosarcoma and impact of salvage surgery

BACKGROUND

Optimal treatment strategies for retroperitoneal leiomyosarcoma (RPLMS), particularly recurrent disease, are unknown.

METHODS

We searched the tumor registry at The University of Texas MD Anderson Cancer Center (MDACC) to identify patients with RPLMS treated between 1994 and 2013.

RESULTS

We identified 172 patients with a diagnosis of a RPLMS. Among the 85 patients who underwent complete resection included in the survival analysis, the median overall survival (OS) was 8.3 years (95% confidence interval [CI], 5.7-12.3), 5-year local recurrence rate was 21%, and 5-year distant metastasis rate was 47%. Among 114 patients who experienced recurrence, patients who underwent salvage surgery for recurrent disease had longer OS after recurrence than patients who did not undergo salvage surgery (median survival after recurrence 5.6 vs 3.3 years, 3-year OS rates after recurrence 72.6% vs 58.1%, HR 0.402 [95%CI, 0.243-0.666]; P = 0.0004). Whether salvage surgery was performed for local or distant recurrence was not associated with OS. Patients who had a longer disease-free interval (≥12 months) had better progression-free survival after salvage surgery than those who had a shorter interval (HR, 0.437 [95%CI, 0.244-0.783]; P = 0.0055).

CONCLUSIONS

We recommend that salvage surgery be considered for selected patients with local or distant recurrence of RP LMS.

Incidentally discovered well-differentiated retroperitoneal liposarcoma with inguinal canal herniation: report of 2 cases

Well-differentiated retroperitoneal liposarcomas are slow growing and low-grade tumors, reaching usually huge size before being symptomatic and so diagnosed, therefore with increase of the surgical risk and of the probability of dedifferentiation. Inguinal location of these tumors is unusual and rarely diagnosed.

Looking for answers: the current status of neoadjuvant treatment in localized soft tissue sarcomas

PURPOSE

Sarcomas are a rare and heterogeneous variant of cancer. The standard of care treatment involves surgical resection with radiation in high-risk patients. Despite appropriate treatment approximately 50 % of patients will suffer and die from recurrent disease. The purpose of this article is to review the current evidence concerning the use of neoadjuvant chemotherapy with or without radiation in soft tissue sarcomas.

METHODS

An in-depth literature search was conducted using Ovid Medline and PubMed.

RESULTS

The most active chemotherapeutic agents in sarcoma are anthracyclines and ifosfamide. Adjuvant chemotherapy trials show only minimal benefit. Neoadjuvant chemotherapy offers the potential advantage of reducing the extent of surgery, increasing the limb salvage rate, early exposure of micrometastatic disease to chemotherapy, and assessment of tumor response to chemotherapy. Some retrospective and phase II trials suggest a benefit to neoadjuvant chemotherapy. Unfortunately, no clearly positive phase III prospectively randomized trials exist for neoadjuvant therapy in soft tissue sarcomas.

CONCLUSIONS

The current neoadjuvant chemotherapy trials that do exist are heterogeneous resulting in conflicting results. However, neoadjuvant chemotherapy with or without radiation can be considered in patients with high-risk disease in an attempt to improve long-term outcomes.

Unclassified sarcomas: a study to improve classification in a cohort of Golden Retriever dogs

Morphologically, canine soft-tissue sarcomas (STSs) resemble human STSs. In humans, proper classification of STSs is considered essential to improve insight in the biology of these tumors, and to optimize diagnosis and therapy. To date, there is a paucity of data published on the significance of detailed classification of STSs in the dog. We revised a cohort (n = 110) of proliferative lesions obtained from a study in Golden Retrievers that were considered "soft tissue sarcoma, not otherwise specified or of uncertain subtype" in order to optimize the diagnoses of these lesions. The criteria according to the veterinary WHO classification, recent veterinary literature, and the WHO classification for humans were applied. Revision was initially based on morphologic characteristics of hematoxylin and eosin-stained histologic sections of the neoplasms. If considered necessary (n = 76), additional immunohistochemistry was applied to aid characterization. The diagnosis of STS was confirmed in 75 neoplasms (68%). Of this group, diagnosis of a specific subtype of the STSs was possible in 58 neoplasms. Seven neoplasms had morphologic characteristics that were suggestive for sarcoma subtypes only described in the WHO classification for humans. Seventeen neoplasms remained "unclassified STSs." Thirty-one lesions (28%) were diagnosed "neoplasm, not being STS." Four lesions (4%) were considered nonneoplastic. Because incorrect classification of a tumor could lead to inappropriate therapeutic intervention and prognostication, the results of our study clearly illustrate the importance of revision and further diagnosis of "unclassified STSs" in dogs.

Soft tissue sarcoma in the dog - part 1: a current review

Soft tissue sarcomas are derived from tissues of mesenchymal origin. Although local recurrence following surgical resection is the characteristic challenge in their management, 40% dogs with high-grade tumours may also develop metastatic disease, despite successful local control. Soft tissue sarcoma is a complex disease and there are many uncertainties regarding the biology and optimal clinical management. There are currently no diagnostic tests that can reliably predict the amount of surgical margin required for a particular tumour, so there can be a mismatch between treatment and disease. Historically, the tendency has been to always recommend wide excision margins but this is not fully supported by recent evidence. A selection bias for less aggressive soft tissue sarcomas in primary care practice can account for good outcomes that are achieved despite narrow surgical excision margins. On the other hand, inappropriately conservative treatment will adversely affect outcomes for patients with more aggressive disease. This review provides an update on the current understanding of management of canine soft tissue sarcomas.

Variability in Patterns of Recurrence After Resection of Primary Retroperitoneal Sarcoma (RPS): A Report on 1007 Patients From the Multi-institutional Collaborative RPS Working Group

BACKGROUND

Retroperitoneal sarcomas (RPS) are rare tumors composed of several well defined histologic subtypes. The aim of this study was to analyze patterns of recurrence and treatment variations in a large population of patients, treated at reference centers.

METHODS

All consecutive patients with primary RPS treated at 6 European and 2 North American institutions between January 2002 and December 2011 were included. Five, 8, and 10-year overall survival (OS) and crude cumulative incidence (CCI) of local recurrence (LR) and distant metastasis (DM) were calculated. Multivariate analyses for OS, CCI of LR, and DM were performed.

RESULTS

In all, 1007 patients were included. Median follow-up was 58 months (first and third quartile range 36-90). The 5, 8, and 10-year OS were 67% [95% confidence interval (CI), 63, 70), 56% (95% CI, 52, 61), and 46% (95% CI, 40, 53). The 5, 8, and 10-year CCI of LR and DM were 25.9 (95% CI, 23.1, 29.1), 31.3 (95% CI, 27.8, 35.1), 35% (95% CI, 30.5, 40.1), and 21% (95% CI, 18.4, 23.8%), 21.6 (95% CI, 19.0, 24.6), and 21.6 (95% CI, 19.0, 24.6), respectively. Tumour size, histologic subtype, malignancy grade, multifocality, and completeness of resection were significant predictors of outcome. Patterns of recurrence varied depending on histologic subtype. Different treatment policies at participating institutions influenced LR of well differentiated liposarcoma without impacting OS, whereas discrepancies in adjuvant systemic therapies did not impact LR, DM, or OS of leiomyosarcoma.

CONCLUSIONS

Reference centers are critical to outcomes of RPS patients, as the management strategy requires specific expertise. Histologic subtype predicts patterns of recurrence and should inform management decision. A prospective international registry is under preparation, to further define our understanding of this disease.

Primitive sarcoma of the breast: new insight on the proper surgical management

BACKGROUND

Primitive sarcoma of the breast is a rare and challenging disease at high risk of recurrence and with poor prognosis. There are controversies in the diagnosis and management of such solid tumor due to its rarity and heterogeneity. This sarcoma is poorly responsive to both chemotherapy and radiotherapy, thus, surgery is the first and most important therapeutic approach. However, given the rarity of this type tumor it has not be possible to standardize unique guidelines for the proper surgical strategy to adopt. Here, we performed a retrospective study of new 10 cases of primitive sarcoma of the breast that underwent either mastectomy or a more conservative quadrantectomy, in the attempt to better standardize correct surgical indications.

METHODS

Ten new cases of primitive sarcoma of the breast were registered between 2002 and 2012 and constituted the study group. They underwent either mastectomy or quadrantectomy and the clinical, prognostic and survival characteristics after surgery were analysed.

RESULTS

Within the group of patients treated with mastectomy, two had metastasis and died because of that. Among the five patients treated with quadrantectomy four are alive and free of disease after 3 to 5 years follow-up, while the patient with sarcoma arising in pregnancy, although is still alive, developed lung metastases four years after surgery.

CONCLUSIONS

The first and most important therapeutic approach to primary sarcomas of the breast is surgical which has the purpose to achieve radical tumor excision to prevent local recurrence and skip metastases. However, given the rarity of the condition and the consequent small number of cases in this, like in similar studies, it is not possible to draw any definitive conclusions and further studies with larger numbers are necessary. However it would appear that performing a larger procedure such as mastectomy rather than performing a more limited one such as a quadrantectomy, has no advantage in terms of overall prognosis.

Older age impacts radiotherapy-related outcomes in soft tissue sarcoma

BACKGROUND

Radiation therapy (RT) is a standard component in the multimodality management of localized soft tissue sarcoma (STS). Increasing studies are focusing on biological modifiers that may influence the host's response to RT, including immunologic mechanisms known to change with the aging process. We hypothesized that the effects of RT would be influenced by age, contributing to differences in treatment outcome.

METHODS

Using Surveillance, Epidemiology, and End Results (1990-2011), we identified 30,898 adult patients (>18 y) with nonmetastatic STS undergoing initial surgery. We compared patient demographics, tumor characteristics, and treatments by age. Multivariable analyses were used to analyze overall survival (OS) and disease-specific survival (DSS). Hazard ratios (HRs) were calculated based on multivariable Cox proportional hazards models.

RESULTS

Mean age at diagnosis was 56.6 ± 16.8 y, and 33.6% of patients were ≥65 y. Of the total, 52.1% of patients were male and 67% were white; 59.9% of patients underwent surgery alone, 33.3% received adjuvant RT, and 6.8% neoadjuvant RT. On multivariable analysis, age, sex, year of diagnosis, histology, grade, size, marital status, and RT predicted OS, whereas age, year of diagnosis, ethnicity, histology, site, grade, RT, size, and marital status predicted DSS. In all patients, RT was associated with improved OS and DSS compared to surgery alone (median OS 136 ± 13 mo with RT versus 118 ± 9 mo without RT and 5-y OS 63.2 ± 1.4% with RT versus 60.5 ± 1.2% without, P < 0.01). Patients ≥65 y derived greater improvements in OS and DSS compared with patients <65 y. These benefits were most notable after neoadjuvant RT with patients ≥65 y having significantly better OS (HR = 0.63; 95% confidence interval = 0.53-0.75), whereas patients <65 y did not (HR = 0.96; 95% confidence interval = 0.83-1.10). In addition, interaction testing demonstrated a significant modifier effect between RT and age (P < 0.05).

CONCLUSIONS

RT is associated with improved survival in patients with STS undergoing surgical treatment, but improvements in oncologic outcome with RT were greatest among older patients. Further studies into the mechanism of these age-related effects are needed.

Imaging features and metastatic pattern of non-IVC retroperitoneal leiomyosarcomas: are they different from IVC leiomyosarcomas?

PURPOSE

The purposes of this study were to describe the imaging features and metastatic pattern of non-inferior vena cava (IVC) retroperitoneal leiomyosarcomas (non-IVC LMS) and to compare them with those of IVC leiomyosarcomas (IVC LMS) to assess any differences between the 2 groups.

MATERIALS AND METHODS

In this institutional review board-approved, Health Insurance Portability and Accountability Act-compliant retrospective study, all 56 patients with pathologically confirmed primary retroperitoneal leiomyosarcoma (34 non-IVC LMS and 22 IVC LMS) seen at our tertiary cancer center during a 10-year period were included. All available imaging of primary tumor (18 non-IVC LMS and 19 IVC LMS) and follow-up imaging studies (on all 56 patients) were reviewed in consensus by 2 fellowship-trained oncoradiologists. Imaging features and metastatic spread of non-IVC LMS were described and compared with those of IVC LMS. Continuous variables were compared using the Student t test, binary variables with the Fisher exact test, and survival using the log-rank test.

RESULTS

Non-inferior vena cava retroperitoneal leiomyosarcomas had a mean size of 11.3 cm (range, 3.7-27 cm) and most commonly occurred in the perirenal space (16/18). Primary tumors were hyperattenuating to muscle (11/18) and showed heterogeneous enhancement (17/18). Lungs (22/34), peritoneum (18/34), and liver (18/34) were the most common metastatic sites. There was no significant difference between the imaging features and metastatic pattern of non-IVC and IVC LMS. Although non-IVC LMS presented at a more advanced stage (P < 0.002), there was statistically non-significant trend toward better median survival of non-IVC LMS (P = 0.07).

CONCLUSIONS

Non-inferior vena cava retroperitoneal leiomyosarcomas are large heterogeneous tumors arising in the perirenal space and frequently metastasize to lungs, peritoneum, and liver. From a radiologist's perspective, non-IVC LMS behave similar to IVC-LMS.

Adjuvant radiotherapy in retroperitoneal sarcomas. A Scandinavian Sarcoma Group study of 97 patients

BACKGROUND

Currently there is no consensus on the use of adjuvant radiotherapy (RT) in retroperitoneal sarcoma (RPS). We have analysed clinical outcomes in patients with localised RPS treated at two Scandinavian Sarcoma Group (SSG) centres: Haukeland University Hospital (HUH), Bergen, Norway and Skåne University Hospital (SUH), Lund, Sweden to clarify the effects of adjuvant RT on local control and overall survival (OS).

MATERIAL AND METHODS

Local databases and registers at HUH and SUH as well as the SSG central register were used to identify RPS patients. Patients with localised RPS who underwent surgery in Bergen between 1988 and 2009 and in Lund from 1998 to 2009 were included. Medical records were examined for clinical data, tumour characteristics, treatment factors and follow-up status. Archived tumour sections and tumour tissue were reviewed, and when necessary, restained and reclassified. Cox regression was used to analyse the association of potential prognostic factors with local recurrence-free survival (LRFS), metastasis-free survival (MFS) and OS.

RESULTS

The study included 97 patients: 52 from Norway and 45 from Sweden. The proportion of high-grade tumours was 73%. The five-year LRFS, MFS and OS were 55%, 59% and 60%, respectively. RT was significantly associated with improved local control resulting in a five-year LRFS of 77% compared with 39% without (p < 0.001). Furthermore, five-year OS was 71% in the RT group in contrast to 52% with surgery alone (p = 0.019). In the adjusted analysis RT proved to be a significant factor also for MFS (HR = 0.42, 95% CI 0.20-0.88, p = 0.021). In addition, high-grade malignancy, large tumour and positive surgical margin were risk factors for local recurrence. High malignancy grade was the only significant adverse prognostic factor for metastasis. High age and high-grade malignancy were negative prognostic factors for OS.

CONCLUSION

Adjuvant RT was significantly associated with an improved five-year LRFS and OS.

Large Retroperitoneal Liposarcoma Diagnosed upon Radiological Evaluation of Mild Right-Sided Inguinal Hernia

While inguinal hernia is common in the primary care office, the differential diagnosis is extensive and includes infectious, inflammatory and neoplastic processes. Varicocele is another frequent, generally benign condition which occasionally reflects serious disease entities. Left-sided or bilateral varicoceles account for the overwhelming majority of varicoceles because the left gonadal vein drains into the left renal vein in contrast to the right gonadal vein, which drains directly into the inferior vena cava, thus making left-sided or bilateral venous congestion more likely. Presence of an uncommon unilateral right-sided varicocele thus warrants further radiological workup, in particular CT abdomen and pelvis, to evaluate for retroperitoneal pathology. We describe a case in which appropriate use of a variety of imaging modalities including testicular ultrasound and CT led to an important diagnosis of a large, well-differentiated liposarcoma in the right retroperitoneum of a patient with a right-sided groin mass.

A phase II study evaluating neo-/adjuvant EIA chemotherapy, surgical resection and radiotherapy in high-risk soft tissue sarcoma

BACKGROUND

The role of chemotherapy in high-risk soft tissue sarcoma is controversial. Though many patients undergo initial curative resection, distant metastasis is a frequent event, resulting in 5-year overall survival rates of only 50-60%. Neo-adjuvant and adjuvant chemotherapy (CTX) has been applied to achieve pre-operative cytoreduction, assess chemosensitivity, and to eliminate occult metastasis. Here we report on the results of our non-randomized phase II study on neo-adjuvant treatment for high-risk STS.

METHOD

Patients with potentially curative high-risk STS (size ≥ 5 cm, deep/extracompartimental localization, tumor grades II-III [FNCLCC]) were included. The protocol comprised 4 cycles of neo-adjuvant chemotherapy (EIA, etoposide 125 mg/m(2) iv days 1 and 4, ifosfamide 1500 mg/m2 iv days 1 - 4, doxorubicin 50 mg/m(2) day 1, pegfilgrastim 6 mg sc day 5), definitive surgery with intra-operative radiotherapy, adjuvant radiotherapy and 4 adjuvant cycles of EIA.

RESULT

Between 06/2005 and 03/2010 a total of 50 subjects (male = 33, female = 17, median age 50.1 years) were enrolled. Median follow-up was 30.5 months. The majority of primary tumors were located in the extremities or trunk (92%), 6% originated in the abdomen/retroperitoneum. Response by RECIST criteria to neo-adjuvant CTX was 6% CR (n = 3), 24% PR (n = 12), 62% SD (n = 31) and 8% PD (n = 4). Local recurrence occurred in 3 subjects (6%). Distant metastasis was observed in 12 patients (24%). Overall survival (OS) and disease-free survival (DFS) at 2 years was 83% and 68%, respectively. Multivariate analysis failed to prove influence of resection status or grade of histological necrosis on OS or DFS. Severe toxicities included neutropenic fever (4/50), cardiac toxicity (2/50), and CNS toxicity (4/50) leading to CTX dose reductions in 4 subjects. No cases of secondary leukemias were observed so far.

CONCLUSION

The current protocol is feasible for achieving local control rates, as well as OS and DFS comparable to previously published data on neo-/adjuvant chemotherapy in this setting. However, the definitive role of chemotherapy remains unclear in the absence of large, randomized trials. Therefore, the current regimen can only be recommended within a clinical study, and a possibly increased risk of secondary leukemias has to be taken into account.

TRIAL REGISTRATION

ClinicalTrials.gov NCT01382030, EudraCT 2004-002501-72.

Banked depopulated vena caval homograft: a new strategy to restore caval continuity

This study reports one case of primary inferior vena cava (IVC) leiomyosarcoma. A 67-year-old woman was referred to the authors' clinic for evaluation. She presented complaining of epigastric and right upper abdominal quadrant pain. Contrast-enhanced abdominal computed tomography scan revealed a 5.2 × 6.4 cm heterogeneously enhancing mass involving the anteromedial aspect of the IVC, below the renal vein (segment I), deforming the duodenum. There was a partial intraluminal extension in the IVC. Laparotomic resection was performed, with total en bloc excision of the lower IVC tumor. The caval continuity was restored with concomitant interposition of a banked depopulated vena cava homograft. Histological findings showed leiomyosarcoma originating from IVC. The postoperative course was uneventful: Neither recurrence nor metastasis was evident at 4 years postsurgery.