Retroperitoneal soft tissue sarcomas

Current classification, treatment options, and new perspectives in the management of adipocytic sarcomas

Sarcomas are a heterogeneous group of mesenchymal tumors arising from soft tissue or bone, with an uncertain etiology and difficult classification. Soft tissue sarcomas (STSs) account for around 1% of all adult cancers. Till date, more than 50 histologic subtypes have been identified. Adipocyte sarcoma or liposarcoma (LPS) is one of the most common STS subtypes, accounting for 15% of all sarcomas, with an incidence of 24% of all extremity STSs and 45% of all retroperitoneal STSs. The new World Health Organization classification system has divided LPS into four different subgroups: atypical lipomatous tumor/well-differentiated LPS, dedifferentiated LPS, myxoid LPS, and pleomorphic LPS. These lesions can develop at any location and exhibit different aggressive potentials reflecting their morphologic diversity and clinical behavior. Patients affected by LPS should be managed in specialized multidisciplinary cancer centers. Whereas surgical resection is the mainstay of treatment for localized disease, the benefits of adjuvant and neoadjuvant chemotherapy are still unclear. Systemic treatment, particularly chemotherapy, is still limited in metastatic disease. Despite the efforts toward a better understanding of the biology of LPS, the outcome of advanced and metastatic patients remains poor. The advent of targeted therapies may lead to an improvement of treatment options and clinical outcomes. A larger patient enrollment into translational and clinical studies will help increase the knowledge of the biological behavior of LPSs, test new drugs, and introduce new methodological studies, that is, on treatment response.

Management of Recurrent Retroperitoneal Sarcoma (RPS) in the Adult: A Consensus Approach from the Trans-Atlantic RPS Working Group

INTRODUCTION

Retroperitoneal soft tissue sarcomas (RPS) are rare tumors. Surgery is the mainstay of curative therapy, but local recurrence is common. No recommendations concerning the best management of recurring disease have been developed so far. Although every effort should be made to optimize the initial approach, recommendations to treat recurring RPS will be helpful to maximize disease control at recurrence.

METHODS

An RPS transatlantic working group was established in 2013. The goals of the group were to share institutional experiences, build large multi-institutional case series, and develop consensus documents on the approach to this difficult disease. The outcome of this document applies to recurrent RPS that is nonvisceral in origin. Included are sarcomas of major veins, undifferentiated pleomorphic sarcoma of psoas, ureteric leiomyosarcoma (LMS). Excluded are desmoids-type fibromatosis, angiomyolipoma, gastrointestinal stromal tumors, sarcomas arising from the gut or its mesentery, uterine LMS, prostatic sarcoma, paratesticular/spermatic cord sarcoma, Ewing sarcoma, alveolar/embryonal rhabdomyosarcoma, sarcoma arising from teratoma, carcinosarcoma, sarcomatoid carcinoma, clear cell sarcoma, radiation-induced sarcoma, paraganglioma, and malignant pheochromocytoma.

RESULTS

Recurrent RPS management was evaluated from diagnosis to follow-up. It is a rare and complex malignancy that 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, but some patients may experience prolonged disease control also at recurrence, when the approach is optimized and follows the recommendations contained herein.

CONCLUSIONS

International collaboration is critical for adding to the present knowledge. A transatlantic prospective registry has been established.

Clinical outcomes of tissue expanders on adjuvant radiotherapy of resected retroperitoneal sarcoma

We investigated the efficacy and safety of a tissue expander (TE) for adjuvant radiotherapy (RT) of resected retroperitoneal sarcoma (RPS).This study was conducted with 37 patients with RPS who received resection with or without TE insertion followed by RT from August 2006 to June 2012 at Samsung Medical Center. Among the 37 patients, TE was inserted in 19. The quality of TE insertion was evaluated according to the correlation of clinical target volume and retroperitoneal surface volume covered by TE and was defined as follows: excellent, ≥85%; good, 70% to 85%; fair, 50% to 70%; and poor, <50%. The median follow-up period after surgery was 47.9 months (range, 5.5-85.5 months).The quality of TE insertion was excellent in 7 (36.8%), good in 5 (26.3%), fair in 4 (21.0%), and poor in 3 (16.7%) patients. A significantly higher biologically equivalent dose (BED, α/β = 10) was used in patients who had TE insertion (median, 64.8 vs. 60.0 Gy, P = 0.01). Local control was 39.7%, and overall survival was 76.4% at 5 years. Local control was significantly higher in patients who received ≥65 Gy of BED, 100.0% in contrast to 22.8% (P = 0.01). One patient with a history of multiple tumor resections showed abdominal infection with duodenal perforation of uncertain cause but had the potential of being related to TE and/or RT. Otherwise there were no ≥grade III acute or late toxicities.TE for adjuvant RT in RPS is feasible for delivering a higher RT dose with acceptable toxicity.

Leiomyosarcoma of the Mesenteric Root: A Strategic Location of a Rare Tumor

High mesenteric root sarcomas are difficult to manage due to their proximity to the superior mesenteric vessels. Resection of these tumors along with the blood vessels may lead to a complicated and protracted convalescence for the patient. Resection remains the main treatment modality for these tumors. During operation on high mesenteric root sarcomas, sound clinical judgment is needed for the decision not to sacrifice vital blood vessels.

Outcome following resection of retroperitoneal sarcoma

Background

Retroperitoneal sarcoma comprises a range of different histological subtypes with dissimilar behaviour and biology. This study sought to characterize the morbidity and mortality associated with multivisceral resection and oncological outcomes according to subtype.

Methods

All patients undergoing resection of primary retroperitoneal sarcoma at the Royal Marsden Hospital between January 2005 and December 2014 were identified from a database.

Results

Some 362 patients underwent resection, with 292 requiring multivisceral resection. The 30-day mortality rate was 1·4 per cent (5 patients), the 30-day morbidity rate was 15·7 per cent (57 patients), and 27 patients required a return to theatre. Age over 75 years was predictive of 30-day mortality (hazard ratio 1·37, 95 per cent c.i. 1·13 to 1·65). The overall disease-specific survival rate at 3 years was 81·2 per cent. For well differentiated liposarcoma, dedifferentiated liposarcoma and leiomyosarcoma, 3-year local recurrence-free survival rates were 98 (95 per cent c.i. 83 to 99), 56·7 (45·7 to 66·2) and 80 (67 to 89) per cent respectively. At 3 years the distant metastasis-free survival rate was 100, 85·9 (77·4 to 91·4) and 65 (49 to 77) per cent, and the disease-specific survival rate was 97 (89 to 99), 78·5 (74·6 to 82·4) and 79 (63 to 85) per cent for well differentiated liposarcoma, dedifferentiated liposarcoma and leiomyosarcoma respectively.

Conclusion

Resection of retroperitoneal sarcoma was associated with a 30-day mortality rate of less than 2 per cent and a morbidity rate of 15·7 per cent. The overall 3-year disease-specific survival rate was 81·2 per cent.

Challenges in the Surgical Treatment of Retroperitoneal Sarcomas

The objective of this study is to assess long-term prognosis and patterns of failure in patients with retroperitoneal sarcoma who underwent surgery with curative intent at a single institution. We also provide a thorough review of the literature including several series and widely variable data regarding local and distant failure. During a 25-year period (1988-2013), 45 consecutive patients who underwent surgery for retroperitoneal sarcoma at a single referral center were reviewed retrospectively. We recorded and analyzed the presenting symptoms, type of surgical excision, and the 5-year survival rate as well as the local recurrence rate of patients with complete tumor resection. Overall survival is significantly diminished in patients in whom resection margins are not adequate. In our series, 5-year recurrence rate for patients with complete and incomplete resection of the tumor was 30.76 and 68.42 %, respectively. The 5-year survival rate was 51.12 %, and the 5-year survival rate according to type of resection was 76.93 % for complete and 15.79 % for incomplete resections. Local recurrence after first surgery and high-grade malignancy are associated with poor survival. The role of radiation therapy and chemotherapy in the treatment of retroperitoneal sarcoma (RPS) should be investigated further. Complete en bloc resection of the tumor mass and adjacent structures is the single most important factor that improves survival.

Retroperitoneal liposarcoma: current insights in diagnosis and treatment

Retroperitoneal liposarcoma (RLS) is a rare, biologically heterogeneous tumor that present considerable challenges due to its size and deep location. As a consequence, the majority of patients with high-grade RLS will develop locally recurrent disease following surgery, and this constitutes the cause of death in most patients. Here, we review current insights and controversies regarding histology, molecular biology, extent of surgery, (neo)adjuvant treatment, and systemic treatment including novel targeted agents in RLS.

Metastasis in dedifferentiated liposarcoma: Predictors and outcome in 148 patients

OBJECTIVE

To describe the pattern of dedifferentiated liposarcoma (DDLPS) metastases and to analyze their predictors and outcome.

MATERIALS AND METHODS

In this retrospective study, we reviewed the imaging and clinical records of all consenting patients with histopathology-confirmed DDLPS seen from 2000 through 2012. The predictive value of clinical and histopathologic parameters for metastasis later in the disease course was analyzed using univariate and multivariate analyses. Survival of patients with and without metastasis was compared using Log-rank test.

RESULTS

Records of 148 patients (57 women, 91 men; mean age 59 years, range 30-87 years) were reviewed. Distant metastases were observed in 44/148 patients (29.7%), 9/44 (20.5%) at presentation and 35/44 (79.5%) developing them later at a median interval of 8 months (IQR = 0.80-26 months). Median duration of follow-up was 38 months (IQR = 18-74 months) with 77/148 patients (31 with metastases) deceased at the time of analysis. Median survival was 28 months (IQR = 10-56 months) for patients with metastases and 38 months (IQR, 17-65 months) for patients without metastases (p = 0.0123, Log-Rank test; Hazard ratio 1.79 [95% confidence interval 1.11-2.84]). Lung was the most common site of metastases (33 patients, 22.3%). On univariate analysis, grade and local recurrence were associated with subsequent risk of metastasis where as age, tumor size, site, de novo dedifferentiation, number of previous surgical resections, margin positivity and chemoradiation were not. On multivariate analysis, high tumor grade (p-value = 0.0005, OR 5.05; 95% CI 2.01-13.48) and local recurrence (p-value = 0.0025, OR 4.46; 95% CI 1.67-13.40) predicted metastasis.

CONCLUSION

Lung was most frequent site of DDLPS metastases. Risk of developing metastatic disease was statistically associated with tumor grade and local recurrence. Metastatic disease was associated with decreased survival.

Modern surgical techniques for management of soft tissue sarcomas involving the spine: outcomes and complications

Several types of soft tissue sarcomas may locally extend to the spine. The best therapeutic strategy for such lesions strongly depends on the histological diagnosis. In this article the authors provide an up-to-date review of current guidelines regarding the management of soft tissue sarcomas involving the spine. Special attention is given to outcomes and complications of modern surgical series in order to highlight current challenges in the management of such lesions.

Locoregional disease patterns in well-differentiated and dedifferentiated retroperitoneal liposarcoma: implications for the extent of resection?

BACKGROUND

Well-differentiated (WD)/dedifferentiated (DD) liposarcoma is the most common soft tissue sarcoma of the retroperitoneum. The frequency of distant metastasis is low and the major burden of disease is locoregional. We sought to define the patterns of locoregional disease to help guide surgical decision making.

METHODS

Data were collected from 247 patients with de novo or recurrent tumors treated at our institution from 1993 to early 2012. The number and location of tumors at both initial presentation and subsequent locoregional recurrence were determined by combined analysis of operative dictations and radiologic imaging.

RESULTS

Thirty-four percent of patients had multifocal locoregional disease (two or more tumors) at initial presentation to our institution, including 9 % who had tumors at synchronous remote retroperitoneal sites. The impact of multifocal disease on overall survival was dependent on histologic subtype (WD vs. DD) and disease presentation (de novo vs. recurrence) at the time of resection. Among patients with initial unifocal disease, 57 % progressed to multifocal locoregional disease with subsequent recurrence, including 11 % with new tumors outside of the original resection field. No clinicopathologic or treatment-related variable, including the type or extent of resection, was predictive of either multifocal or 'outside field' progression.

CONCLUSIONS

Multifocal disease is common in patients with WD/DD retroperitoneal liposarcoma, and tumors can also develop at remote, locoregional sites. Surgical resection remains the primary method of locoregional control in this disease; however, the aggressiveness of resection should be individualized, with consideration of both tumor and patient-related factors.

Retroperitoneal sarcomas: patterns of care at diagnosis, prognostic factors and focus on main histological subtypes: a multicenter analysis of the French Sarcoma Group

BACKGROUND

Retroperitoneal sarcomas (RPS) are heterogeneous. No previous study has investigated the impact of specialized surgery, evaluated locoregional relapse (LRR), abdominal sarcomatosis and distant metastatic relapse as separate events, or considered histological subtypes separately. This study addresses these specific points in a homogeneous cohort of patients with completely resected primary RPS.

PATIENTS AND METHODS

We conducted a retrospective analysis of adult patients diagnosed with a RPS between 1 January 1988 and 31 December 2008 and eventually referred to one of 12 centers of the French Sarcoma Group. All cases were centrally reviewed by an expert pathologist.

RESULTS

Five hundred eighty-six patients were included. Median follow-up was 6.5 years [95% confidence interval (CI) 5.9-7.1]. Five hundred thirty-seven patients had localized disease and 389 patients (76%) had macroscopically complete resection of the tumor. In this latter group, the 5-year LRR-free survival rate was 46% [41-52] and the 5-year overall survival (OS) rate was 66% [61-71]. In multivariate analysis, gender, adjacent organ involvement, specialization of the surgeon, piecemeal resection and perioperative radiotherapy were independently associated with LRR. Specialization of the surgeon and piecemeal resection were independently associated with abdominal sarcomatosis whereas histology and adjacent organ involvement were independently associated with distant metastasis. Age, gender, grade, adjacent organ involvement and piecemeal resection were significantly associated with OS. Prognostic factors for LRR and OS were analyzed in well-differentiated and dedifferentiated liposarcomas and leiomyosarcomas. Grade 3 was an independent prognostic factor for OS of dedifferentiated liposarcomas.

CONCLUSION

This study underlines the crucial role of pretherapeutic assessment and meticulous histological examination of RPS as well as the need to consider histological subtypes separately. Surgery in a specialized center and avoidance of piecemeal resection stand out as the two most important prognostic factors for RPS and highlight the importance of treating these patients in specialized centers.

Unusual presentation of retroperitoneal leiomyosarcoma mimicking an adnexal tumor with highly elevated serum CA-19-9

When retroperitoneal leiomyosarcoma develops in pelvic cavity, it often presents similar symptoms and radiological findings to adnexal tumor, therefore obscures diagnostic approaches until an exploratory laparotomy is performed. We report an unusual presentation of retroperitoneal leiomyosarcoma mimicking an adnexal tumor with extremely elevated serum CA-19-9. Though the most of the prominent mass was removed during surgery, there was massive bleeding due to tearing of internal iliac vein while dissecting the ureter close to vessels. This case focuses on the significance of considering retroperitoneal tumor even if the mass is located in ovarian fossa and has highly elevated serum level of CA-19-9. And in attempt of tumor removal, the excision needs to be clean-cut without damaging nerves or vessels around the mass and avoid causing any prospective complications.

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.

Management of recurrent retroperitoneal sarcoma

Approximately 15% of soft tissue sarcomas are retroperitoneal. The occult location and anatomic complexity results in local recurrences in the majority of patients. Predictors of recurrence include histological subtype, completeness of resection, and the hospital case volume. The most significant predictor of outcome following local recurrence is the resectability of the recurrent disease. An understanding of the implication of tumor biology on outcomes is essential in determining optimal management for patients with recurrent retroperitoneal sarcoma.

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.

A clinical phase I/II trial to investigate preoperative dose-escalated intensity-modulated radiation therapy (IMRT) and intraoperative radiation therapy (IORT) in patients with retroperitoneal soft tissue sarcoma

Background

The current standard treatment, at least in Europe, for patients with primarily resectable tumors, consists of surgery followed by adjuvant chemotherapy. But even in this prognostic favourable group, long term survival is disappointing because of high local and distant failure rates. Postoperative chemoradiation has shown improved local control and overalls survival compared to surgery alone but the value of additional radiation has been questioned in case of adjuvant chemotherapy. However, there remains a strong rationale for the addition of radiation therapy considering the high rates of microscopically incomplete resections after surgery. As postoperative administration of radiation therapy has some general disadvantages, neoadjuvant and intraoperative approaches theoretically offer benefits in terms of dose escalation, reduction of toxicity and patients comfort especially if hypofractionated regimens with highly conformal techniques like intensity-modulated radiation therapy are considered.

Methods/Design

The NEOPANC trial is a prospective, one armed, single center phase I/II study investigating a combination of neoadjuvant short course intensity-modulated radiation therapy (5 × 5 Gy) in combination with surgery and intraoperative radiation therapy (15 Gy), followed by adjuvant chemotherapy according to the german treatment guidelines, in patients with primarily resectable pancreatic cancer. The aim of accrual is 46 patients.

Discussion

The primary objectives of the NEOPANC trial are to evaluate the general feasibility of this approach and the local recurrence rate after one year. Secondary endpoints are progression-free survival, overall survival, acute and late toxicity, postoperative morbidity and mortality and quality of life.

Trial registration

NCT01372735.

A clinical phase I/II trial to investigate preoperative dose-escalated intensity-modulated radiation therapy (IMRT) and intraoperative radiation therapy (IORT) in patients with retroperitoneal soft tissue sarcoma

BACKGROUND

Local control rates in patients with retroperitoneal soft tissue sarcoma (RSTS) remain disappointing even after gross total resection, mainly because wide margins are not achievable in the majority of patients. In contrast to extremity sarcoma, postoperative radiation therapy (RT) has shown limited efficacy due to its limitations in achievable dose and coverage. Although Intraoperative Radiation Therapy (IORT) has been introduced in some centers to overcome the dose limitations and resulted in increased outcome, local failure rates are still high even if considerable treatment related toxicity is accepted. As postoperative administration of RT has some general disadvantages, neoadjuvant approaches could offer benefits in terms of dose escalation, target coverage and reduction of toxicity, especially if highly conformal techniques like intensity-modulated radiation therapy (IMRT) are considered.

METHODS/DESIGN

The trial is a prospective, one armed, single center phase I/II study investigating a combination of neoadjuvant dose-escalated IMRT (50-56 Gy) followed by surgery and IORT (10-12 Gy) in patients with at least marginally resectable RSTS. The primary objective is the local control rate after five years. Secondary endpoints are progression-free and overall survival, acute and late toxicity, surgical resectability and patterns of failure. The aim of accrual is 37 patients in the per-protocol population.

DISCUSSION

The present study evaluates combined neoadjuvant dose-escalated IMRT followed by surgery and IORT concerning its value for improved local control without markedly increased toxicity.

TRIAL REGISTRATION

NCT01566123.

Intraduodenal sarcoma recurrence of retroperitoneal origin: an unusual cause for a duodenal obstruction

Soft tissue sarcomas are uncommon tumors, and intraduodenal soft tissue sarcoma manifestation is even more rare. Only three cases of intraduodenal sarcomas have been reported in the literature thus far. Here, we report a case of an intraduodenal recurrence of a retroperitoneal sarcoma causing bowel obstruction. This unusual recurrence pattern likely relates to the patient’s previous resection and radiation treatment, and highlights the benefits, limitations and follow-up strategies after multimodality treatment.

Comparison of three-dimensional (3D) conformal proton radiotherapy (RT), 3D conformal photon RT, and intensity-modulated RT for retroperitoneal and intra-abdominal sarcomas

PURPOSE

To compare three-dimensional conformal proton radiotherapy (3DCPT), intensity-modulated photon radiotherapy (IMRT), and 3D conformal photon radiotherapy (3DCRT) to predict the optimal RT technique for retroperitoneal sarcomas.

METHODS AND MATERIALS

3DCRT, IMRT, and 3DCPT plans were created for treating eight patients with retroperitoneal or intra-abdominal sarcomas. The clinical target volume (CTV) included the gross tumor plus a 2-cm margin, limited by bone and intact fascial planes. For photon plans, the planning target volume (PTV) included a uniform expansion of 5 mm. For the proton plans, the PTV was nonuniform and beam-specific. The prescription dose was 50.4 Gy/Cobalt gray equivalent CGE. Plans were normalized so that >95% of the CTV received 100% of the dose.

RESULTS

The CTV was covered adequately by all techniques. The median conformity index was 0.69 for 3DCPT, 0.75 for IMRT, and 0.51 for 3DCRT. The median inhomogeneity coefficient was 0.062 for 3DCPT, 0.066 for IMRT, and 0.073 for 3DCRT. The bowel median volume receiving 15 Gy (V15) was 16.4% for 3DCPT, 52.2% for IMRT, and 66.1% for 3DCRT. The bowel median V45 was 6.3% for 3DCPT, 4.7% for IMRT, and 15.6% for 3DCRT. The median ipsilateral mean kidney dose was 22.5 CGE for 3DCPT, 34.1 Gy for IMRT, and 37.8 Gy for 3DCRT. The median contralateral mean kidney dose was 0 CGE for 3DCPT, 6.4 Gy for IMRT, and 11 Gy for 3DCRT. The median contralateral kidney V5 was 0% for 3DCPT, 49.9% for IMRT, and 99.7% for 3DCRT. Regardless of technique, the median mean liver dose was <30 Gy, and the median cord V50 was 0%. The median integral dose was 126 J for 3DCPT, 400 J for IMRT, and 432 J for 3DCRT.

CONCLUSIONS

IMRT and 3DCPT result in plans that are more conformal and homogenous than 3DCRT. Based on Quantitative Analysis of Normal Tissue Effects in Clinic benchmarks, the dosimetric advantage of proton therapy may be less gastrointestinal and genitourinary toxicity.

Treatment outcome of postoperative radiotherapy for retroperitoneal sarcoma

Purpose

To evaluate the treatment outcome and prognostic factor after postoperative radiotherapy in retroperitoneal sarcoma.

Materials and Methods

Forty patients were treated with surgical resection and postoperative radiotherapy for retroperitoneal sarcoma from August 1990 to August 2008. Treatment volume was judged by the location of initial tumor and surgical field, and 45-50 Gy of radiation was basically delivered and additional dose was considered to the high-risk area.

Results

The median follow-up period was 41.4 months (range, 3.9 to 140.6 months). The 5-year overall survival (OS) was 51.8% and disease free survival was 31.5%. The 5-year locoregional recurrence free survival was 61.9% and distant metastasis free survival was 50.6%. In univariate analysis, histologic type (p = 0.006) was the strongest prognostic factor for the OS and histologic grade (p = 0.044) or resection margin (p = 0.032) had also effect on the OS. Histologic type (p = 0.004) was unique significant prognostic factor for the actuarial local control.

Conclusion

Retroperitoneal sarcoma still remains as a poor prognostic disease despite the combined modality treatment including surgery and postoperative radiotherapy. Selective dose-escalation of radiotherapy or combination of effective chemotherapeutic agent must be considered to improve the treatment result especially for the histopathologic type showing poor prognosis.

Primary retroperitoneal synovial sarcoma in CT and MRI

Synovial sarcomas are most commonly localized in the extermities, especially the lower thigh and knee areas. Retroperitoneal synovial sarcoma is very rare. We decribe the radiological findings of an adult retroperitoneal synovial sarcoma.

New frontiers in the treatment of liposarcoma, a therapeutically resistant malignant cohort

The adipogenic origin-derived liposarcoma (LPS) family is the most common soft tissue sarcoma histological subtype. This group is composed of three categories as per the 2002 WHO guidelines: (1) well-differentiated and dedifferentiated liposarcoma (WDLPS/DDLPS); (2) myxoid and round cell liposarcoma (MLS and RCL); and (3) pleomorphic liposarcoma (PLS). While clustered together, these histological subtypes are widely diverse in their clinical, pathological, and molecular characteristics. In general, surgery still remains the mainstay of LPS therapy and the only approach offering the potential of cure. Effective therapeutic strategies for locally advanced and metastatic disease are currently lacking and are crucially needed. With the current gradually increasing knowledge of LPS genetic- and epigenetic-associated deregulations, the ultimate goal is to develop drugs that can specifically eliminate LPS cells while sparing normal tissues. This tumor-tailored target-orientated approach will hopefully result in a significant improvement in the outcome of patients suffering from these poor prognosis malignancies.

Intraabdominal and retroperitoneal soft-tissue sarcomas--outcome of surgical treatment in primary and recurrent tumors

BACKGROUND

Surgery is the only curative treatment for intraabdominal and retroperitoneal sarcoma (IaRS). Little is known about how to treat patients with recurrence. We here report the outcome in primary and recurrent sarcoma treated at the Sarcoma Center in Aarhus, Denmark.

METHODS

All patients evaluated for IaRS from June 1998 to May 2008 were enrolled and data on symptoms, signs, means of diagnosis, extent of surgery, perioperative complications, mortality and long time survival were registered. Primary and first-recurrence sarcomas were analyzed separately.

RESULTS

Sixty-five of 73 primary and 22 of 28 first-recurrence IaRS had surgery. Fifty-three (82%) and 11 (50%) patients achieved radical R0 resection. Age and radicality of surgery were independent predictors of death, while recurrence of sarcoma was not. Perioperative mortality was 2.3%. 5-year survival was 70.2% for primary and 51.8% for first-recurrent sarcomas. However, patients with radical surgery had 5-year survival of over 70% in both the primary and recurrent group.

CONCLUSIONS

The radicality of surgery is the most important prognostic factor. Patients with recurrence have an equally good prognosis as those with primary sarcoma if radicality is achieved and such surgery should not be considered only as a palliative effort.

Surgery for retroperitoneal soft tissue sarcomas: aggressive re-resection of recurrent disease is possible

INTRODUCTION

Retroperitoneal soft tissue sarcomas represent a relatively rare and complex therapeutic problem where surgery forms the mainstay of treatment and is technically demanding. In this study, we review a single UK centre's experience with the surgical management of retro-peritoneal soft tissue sarcoma.

PATIENTS AND METHODS

We present analysis of data on patients treated between 1997 and 2006, our first 75 patients. Data collected from the Access database, included patient demographics, staging modalities, peri-operative details, treatment, outcome, pathological diagnosis and subsequent complications.

RESULTS

A total of 75 patients (M:F, 44:31) underwent 115 resectional procedures as part of the management of retroperitoneal soft-tissue sarcoma. There were 12 major complications for the 115 procedures (morbidity of 8.69%). The 30-day operative mortality was zero and the 90-day mortality rate was 1.33% (1/75). Follow-up ranged from 16-131 months. The median disease-free survival was 69 months (range, 59-78 months). Recurrences developed in 46 patients; median time to overall recurrence was 13 months (range, 3-71 months). Of these 46, 22 developed localised recurrence, which was amenable to further resection. In the cohort of patients with recurrent disease, median survival in those who underwent surgery was 53 months (range, 30-76 months) and median survival in those who did not undergo surgery was 30 months (range, 18-41 months) and this difference was statistically significant (log rank, P = 0.01).

CONCLUSIONS

Extensive resectional surgery with minimal morbidity, devoid of mortality is feasible in the treatment of retroperitoneal sarcoma. Development of recurrent disease is a significant factor influencing survival; however, localised recurrences are amenable to surgery and this can lead to improved survival.

Histology-specific nomogram for primary retroperitoneal soft tissue sarcoma

BACKGROUND

This study was conducted to develop a histology-specific nomogram to predict postoperative overall survival (OS) at 5 and 10 years in primary retroperitoneal soft tissue sarcoma (STS).

METHODS

Data registered at a single institution (National Cancer Institute, Milan, Italy) prospective sarcoma database were used. In the present analysis, patients with primary localized retroperitoneal STS resected with curative intent between 1985 and 2007 were included. A parametric piecewise exponential survival multivariate model was used for nomogram development, and internal validation was performed with standard methodologies. Known prognostic variables, such as age, tumor burden, histologic variant (as reviewed by a sarcoma pathologist), grade, and surgical margins were considered as putative predictors.

RESULTS

Among the 192 patients analyzed, within 10 years from surgery, 114 patients were alive, with a median follow-up time of 55 months (interquartile range, 25-104 months). Among the investigated factors, only histologic subtype did not reach significance at the 10% level. The relative hazard increased while increasing tumor size up to about 25 cm, and decreased thereafter.

CONCLUSIONS

A histology-specific nomogram for retroperitoneal STS is now available. It can be used for better assessing the risk of the single patient and then making individualized decisions within the specific subset of retroperitoneal sarcomas. Cross-check external validation should be performed.

Radiotherapy and extent of surgical resection in retroperitoneal soft-tissue sarcoma: multi-institutional analysis of 261 patients

BACKGROUND AND OBJECTIVE

To examine the impact of adjuvant radiotherapy (RT) and surgical technique on survival in retroperitoneal soft-tissue sarcoma.

METHODS

A retrospective analysis was conducted using the National Oncology Database, a proprietary database of aggregated tumor registries owned by IMPAC(R) Medical Systems (Sunnyvale, CA). Patients who received definitive surgery with negative or microscopic-positive margins were included. Multivariate analysis was performed using the Cox proportional hazards model. Survival curves were estimated by the Kaplan-Meier method and were compared for statistical significance (P < 0.05) using the log-rank test.

RESULTS

Two hundred sixty-one patients met inclusion criteria. The median follow-up was 59 months (range 0.2-186 months). The 5-year cause-specific survival (CSS) and local failure-free survival (LFFS) were 73% and 66%, respectively. Grade, margin status, and histology were independent predictors for CSS (P < 0.05). Adjuvant RT was associated with a significant improvement in LFFS over surgery alone (hazard ratio = 0.42, 95% confidence interval 0.21-0.86, P < 0.05). Patients receiving simple excision and RT had a 5-year LFFS of 88%, significantly higher than wide resection with or without RT (log-rank, P < 0.05).

CONCLUSION

Adjuvant RT is associated with a lower risk of local relapse compared to surgery alone. The impact of surgical technique on adjuvant RT efficacy warrants further study.

Surgery combined with brachytherapy in patients with retroperitoneal sarcomas

Purpose

The primary aim of this work was to analyze feasibility of combined treatment of retroperitoneal sarcomas (RS): surgery (S) and intraoperative brachytherapy (IOBRT). The secondary aim was to analyze results and complications after this treatment.

Material and methods

84 patients with retroperitoneal sarcomas were qualified for combined treatment (S and IOBRT) between June 1998 and September 2006. 65 of the patients (77.4%) had local recurrences. Sarcomas with intermediate and high grade of histological malignancy (G2, G3 – 76.2%) were the most frequent within the all surgically treated patients. Resection ability (R0/R1) in analyzed group of patients was estimated as 85% (74 cases). After intraoperative evaluation, 57 (67.8%) patients were qualified for IOBRT. Since 2000, in 34 patients (60%) an adjuvant postoperative external beam radiation therapy (EBRT) in dose of 50 Gy was applied. Median follow-up of the surviving patients was 40 months.

Results

On the basis of the univariate analysis, relevant aspects negatively influencing overall survival rate within the RS group treated with IOBRT were as follows: surgery of sarcoma recurrence (p = 0.002), higher grade of histological malignancy (p = 0.05), histological type different than liposarcoma (p = 0.05) as well as no adjuvant EBRT (p = 0.05). On the basis of multivariate analysis one can ascertain that relevant factors negatively influencing LRFS in RS patients treated with IOBRT were: surgery due to recurrence of sarcoma (p = 0.008) and lack of EBRT (p = 0.01).

Conclusions

Combined treatment (surgery and brachytherapy) was possible to be carried out on 68% of RS patients. The overall number of complications was quite high, however acceptable, taking into consideration the application of extensive, multi-organ treatments in case of sarcoma recurrences in this localization. The results suggest that the method of treatment will improve the final outcome when most of patients will be qualified for treatment of primary sarcomas in experienced centre.

Predictors of survival after resection of retroperitoneal sarcoma: a population-based analysis and critical appraisal of the AJCC staging system

OBJECTIVE

To identify predictors of survival after resection of retroperitoneal sarcoma (RPS) and to evaluate the performance of the American Joint Committee on Cancer (AJCC) staging system for RPS.

SUMMARY BACKGROUND DATA

Previous studies of survival after RPS resection are restricted to at most several institutions, yet the current AJCC staging system for RPS is based entirely on these relatively small studies.

METHODS

Patients undergoing resection of primary RPS from 1988 to 2005 were identified from the Surveillance, Epidemiology, and End Results (SEER) database. Cox proportional hazards models were used to analyze survival and evaluate AJCC staging.

RESULTS

In 1365 patient undergoing resection of primary RPS, the most prevalent histologies were liposarcoma (50%), leiomyosarcoma (26%), and malignant fibrous histiocytoma (11%). Median, 5-year, and 10-year survival after resection were 55 months, 47%, and 27%. Histological subtype (P < 0.001), histological grade (grade 3-4 vs. grade 1; HR, 2.42; P < 0.001), and tumor invasion of adjacent structures (HR, 1.37; P < 0.001) were associated with survival on multivariable analysis. However, tumor size had no prognostic value. Consequently, the AJCC T classification system demonstrated poor discriminatory ability (c = 0.50). The AJCC stage grouping system demonstrated moderate discriminatory ability (c = 0.66) but performed no better than a much simpler system that omits information on tumor size and lymph node metastasis (c = 0.67).

CONCLUSIONS

Indicators of tumor aggressiveness (histological grade and invasion of adjacent structures) as well as histological subtype predict survival after RPS resection. Tumor size, however, does not impact survival. The AJCC staging system for RPS is in need of revision.

Predicting outcome by growth rate of locally recurrent retroperitoneal liposarcoma: the one centimeter per month rule

OBJECTIVE

To identify the prognostic variables that predict disease-specific survival and second local recurrence-free survival in patients with recurrent retroperitoneal liposarcoma so as to guide clinical management.

SUMMARY BACKGROUND DATA

Local recurrence after complete resection of primary retroperitoneal liposarcoma is a common clinical problem that frequently leads to morbidity and mortality. Factors that determine survival in patients with a local recurrence after complete resection of the primary and rerecurrence after resection of the first local recurrence have not been clearly defined.

METHODS

From a prospective sarcoma database we selected 105 patients who had at least one local recurrence following complete resection of a primary retroperitoneal liposarcoma between July 1982 and December 2005. Of these patients, 61 underwent complete resection of their first local recurrence. Study endpoints included second local recurrence-free survival for these 61 patients and disease-specific survival for all 105 patients. Univariate analysis was performed with the Kaplan-Meier method and log-rank test, and multivariate analysis with the Cox proportional hazards model and score test. Local recurrence growth rate was defined as the radiographic size of the local recurrence divided by the time to local recurrence from the primary resection.

RESULTS

Median follow-up was 65 months. Local recurrence size, primary histologic variant and grade, and local recurrence growth rate were independent predictors of disease-specific survival. For those undergoing reresection, local recurrence size and local recurrence growth rate independently influenced development of a second local recurrence. Only patients with local recurrence growth rates of less than 0.9 cm/mo were associated with improved survival after aggressive resection of the local recurrence.

CONCLUSIONS

Local recurrence growth rate is strongly associated with disease-specific survival and local control for patients with completely resected locally recurrent retroperitoneal liposarcoma. Despite aggressive operative management patients with a local recurrence growth rate greater than 0.9 cm/mo were associated with poor outcomes and should be considered for enrollment in clinical trials employing novel agents.

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.

Molecular prognosticators of complex karyotype soft tissue sarcoma outcome: a tissue microarray-based study

BACKGROUND

Molecular markers are currently being utilized as sensitive prognosticators of cancer patient outcome. We sought to identify prognostic biomarkers for complex karyotype soft tissue sarcoma (STS).

MATERIALS AND METHODS

A large (n = 205) clinically annotated tissue microarray (TMA) was constructed and immunostained for several tumor-related markers. Staining was scored via an automated Ariol image analysis system; data were statistically analyzed to evaluate the correlation of clinicopathological and molecular variables with overall survival (OS) and local recurrence.

RESULTS

Multivariable analysis identified older age [hazard ratio (HR) 1.62, P < 0.0001], nonextremity location (HR 2.95, P = 0.001), high tumor grade (HR 2.5, P = 0.02), and increased matrix metalloproteinase (MMP) 2 expression (HR 1.74, P = 0.04) as predictors for poor OS. Similarly, older age (HR 1.51, P = 0.008), nonextremity location (HR 4.09, P = 0.001), and increased MMP2 expression (HR 6.28, P = 0.006) were all found to correlate with shorter local recurrence-free interval. High nuclear p53 expression was associated with shorter STS local recurrence-free interval, with a trend toward significance.

CONCLUSIONS

Data presented indicate that a clinically annotated TMA can be utilized to identify STS-related prognostic markers. Specifically, MMP2 and nuclear p53 should be further evaluated for their potential inclusion in complex karyotype STS staging systems.

Body wall and visceral nonrhabdomyosarcoma soft tissue sarcomas in children and adolescents

BACKGROUND

Predictors of outcome have not been established for pediatric visceral and body wall nonrhabdomyosarcoma soft tissue sarcomas (NRSTS).

METHODS

The study used a retrospective review of clinical features and outcome of 61 patients with visceral and body wall NRSTS evaluated at our institution between March 1962 and December 1999.

RESULTS

Median age at diagnosis was 9.9 years (range, birth to 17.4 years). Tumors were greater than 5 cm in 43 (70%), high grade in 33 (54%), invasive in 25 (41%), and metastatic at presentation in 14 (23%) patients. Visceral tumors (n = 27) were more likely than body wall tumors (n = 34) to be greater than 5 cm (93% vs 53%; P < .001) and invasive (70% vs 18%; P < .001) and were less likely to be resected at diagnosis (44% vs 85%; P = .001). Estimated 10-year event-free survival (EFS) and overall survival (OS) for the entire cohort were 45.5% +/- 6.9% and 56.8% +/- 6.7%, respectively. The 10-year EFS and OS were better for patients with body wall sites than for those with visceral sites (61.8% +/- 8.5% and 67.5% +/- 8.2% vs 24.2% +/- 9.4% and 43.0% +/- 10.3%; P = .004 and P = .004). The 10-year estimated cumulative incidence (CI) of local recurrence was higher for patients with visceral sites than for those with body wall sites (64.3% +/- 9.8% vs 26.5% +/- 7.7%; P = .004), whereas CI of distant recurrence was similar for the 2 sites (15.2% +/- 7.2% vs 23.5% +/- 7.4%; P = .39).

CONCLUSIONS

Pediatric patients with visceral NRSTS are more likely to have invasive, large, and unresectable tumors compared to those with body wall tumors. More than two thirds of visceral NRSTS recur locally, and fewer than half of patients with visceral tumors survive.

Postoperative nomogram for survival of patients with retroperitoneal sarcoma treated with curative intent

BACKGROUND

Current American Joint Committee on Cancer retroperitoneal sarcoma (RPS) staging is not representative of patients with RPS specifically and has limited discriminative power. Our objective was to develop a RPS disease-specific nomogram capable of stratifying patients based on probability of overall survival (OS) after resection.

PATIENTS AND METHODS

In all, 1118 RPS patients were evaluated at our institution (1996-2006). Patients with resectable, nonmetastatic disease were selected (n = 343) and baseline, treatment and outcome variables were retrieved. A nomogram was created and its performance was evaluated by calculating its discrimination (concordance index) and calibration and by subsequent internal validation.

RESULTS

Median follow-up and OS were 50 and 59 months, respectively. Independent predictors of OS were included in the nomogram: age (> or = 65), tumor size (> or = 15 cm), type of presentation (primary versus recurrent), multifocality, completeness of resection and histology. The concordance index was 0.73 [95% confidence interval (CI) 0.71-0.75] and the calibration was excellent, with all observed outcomes within the 95% CI of each predicted survival probability.

CONCLUSIONS

A RPS-specific postoperative nomogram was developed. It improves RPS staging by allowing a more dynamic and robust disease-specific risk stratification. This prognostic tool can help in patient counseling and for selection of high-risk patients that may benefit from adjuvant therapies or inclusion into clinical trials.