Resectability and survival in retroperitoneal sarcomas

Lifelong Imaging Surveillance is Indicated for Patients with Primary Retroperitoneal Liposarcoma

BACKGROUND

Surveillance imaging of patients with retroperitoneal liposarcoma (RP-LPS) after surgical resection is based on a projected risk of locoregional and distant recurrence. The duration of surveillance is not well defined because the natural history of RP-LPS after treatment is poorly understood. This study evaluated the long-term risk of recurrence and disease-specific survival (DSS) for a cohort of patients with at least 10 years of progression-free survival (10yr-PFS) from their primary resection.

METHODS

The prospective University of California, Los Angeles (UCLA) Sarcoma Database identified RP-LPS patients with 10yr-PFS after initial resection. The patients in the 10yr-PFS cohort were subsequently evaluated for recurrence and DSS. The time intervals start at date of initial surgical resection. Cox proportional hazards models were used to determine factors associated with recurrence and DSS.

RESULTS

From 1972 to 2010, 76 patients with RP-LPS had at least 10 years of follow-up evaluation. Of these 76 patients, 39 (51%) demonstrated 10yr-PFS. The median follow-up period was 15 years (range 10-33 years). Among the 10yr-PFS patients, 49% (19/39) experienced a recurrence at least 10 years after surgery. Of those who experienced recurrence, 42% (8/19) died of disease. Neither long-term recurrence nor DSS were significantly associated with age, sex, tumor size, LPS subtype, surgical margin, or perioperative treatment with radiation or chemotherapy.

CONCLUSION

Patients who have primary RP-LPS treated with surgical resection ± multimodality therapy face a long-term risk of recurrence and disease-specific death unacknowledged by current surveillance imaging guidelines. Among the patients with 10yr-PFS, 49% experienced a recurrence, and 42% of those died of disease. These findings suggest a need for lifelong surveillance imaging for patients with RP-LPS.

Comparison of 3D Conformal Proton Therapy, Intensity-Modulated Proton Therapy, and Intensity-Modulated Photon Therapy for Retroperitoneal Sarcoma

Background

External beam radiation therapy (RT) for retroperitoneal sarcoma often requires treatment of large target volumes close to critical normal tissues. Radiation may be limited by adjacent organs at risk (OAR). Intensity-modulated radiation therapy has been shown to improve target coverage and reduce doses to OAR.

Objectives

To compare target coverage and dose to OAR with 3D conformal proton therapy (3D CPT), intensity-modulated proton therapy (IMPT), and intensity-modulated photon therapy (IMXT).

Methods

We performed a comparative study of treatment plans with 3D CPT, IMPT, and IMXT for ten patients with retroperitoneal sarcomas. RT was delivered to 50.4 Gy to the clinical target volume (CTV), the structures considered at risk for microscopic disease.

Results

CTVs ranged from 74 to 357 cc (mean 188 cc). Dose conformity was improved with IMPT, while 3D CPT provided better dose homogeneity. Mean dose to the liver, small bowel, and stomach was reduced with IMPT compared with 3D CPT or IMXT.

Conclusions

IMPT, 3D CPT, and IMXT provide excellent target coverage for retroperitoneal sarcomas. OAR dose is lower with IMPT and 3D CPT, and IMPT achieves the closest conformity. These techniques offer the opportunity for further dose escalation to areas with positive margins.

Aggressive Surgical Approach for Treatment of Primary and Recurrent Retroperitoneal Soft Tissue Sarcoma

To analyze treatment and survival in a series of resected patients with primary or recurrent retroperitoneal sarcoma (RPS) treated and prospectively followed at a single institution. Between July 1994 and December 2015, 89 patients (36 M, 53 F; mean age 60 years, range 25-79) were evaluated. For the purpose of analysis, complete resection was defined as removal of gross tumor with histologically confirmed clear resection margins. Eighty-three out of the 89 patients (93%), 46 of whom affected by primary RPS, and 37 by recurrent RPS, underwent surgical exploration. Sixty-two had a grossly and microscopically complete resection. Fifty-three out of 83 patients (64%) underwent removal of contiguous intra-abdominal organs. Preoperative mortality was nil and significant preoperative complications occurred in six cases only (7%). High-grade tumor pointed out to be a significant variable for a worse survival in all 83 patients amenable to undergo surgical resection (57% 5 years survival for low grade vs 14% for high grade; P = 0.0004). Among completely resected patients, only histologic grade clearly affected disease-free survival (72% 5 years survival for low grade vs 50% for high grade; P = 0.04), while the role of preoperative blood transfusions (67% 5 years survival for non-transfused patients vs 29% for transfused patients; P = 0.05) has to be evaluated in connection to patient complexity. Histological grade and recurrence are the most valuable prognostic predictors; in this clinical subset, an aggressive surgical approach in both primary and recurrent RPS is associated with a best long-term survival and disease-free survival.

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

PURPOSE

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

METHODS AND MATERIALS

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

RESULTS

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

CONCLUSIONS

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

Synthetic Biomaterials from Metabolically Derived Synthons

The utility of metabolic synthons as the building blocks for new biomaterials is based on the early application and success of hydroxy acid based polyesters as degradable sutures and controlled drug delivery matrices. The sheer number of potential monomers derived from the metabolome (e.g., lactic acid, dihydroxyacetone, glycerol, fumarate) gives rise to almost limitless biomaterial structural possibilities, functionality, and performance characteristics, as well as opportunities for the synthesis of new polymers. This review describes recent advances in new chemistries, as well as the inventive use of traditional chemistries, toward the design and synthesis of new polymers. Specific polymeric biomaterials can be prepared for use in varied medical applications (e.g., drug delivery, tissue engineering, wound repair, etc.) through judicious selection of the monomer and backbone linkage.

Histologic and genetic advances in refining the diagnosis of "undifferentiated pleomorphic sarcoma"

Undifferentiated pleomorphic sarcoma (UPS) is an inclusive term used for sarcomas that defy formal sub-classification. The frequency with which this diagnosis is assigned has decreased in the last twenty years. This is because when implemented, careful histologic assessment, immunohistochemistry, and ultra-structural evaluation can often determine lineage of differentiation. Further attrition in the diagnostic frequency of UPS may arise by using array-comparative genomic hybridization. Gene expression arrays are also of potential use as they permit hierarchical gene clustering. Appraisal of the literature is difficult due to a historical perspective in which specific molecular diagnostic methods were previously unavailable. The American Joint Committee on Cancer (AJCC) classification has changed with different inclusion criteria. Taxonomy challenges also exist with the older term “malignant fibrous histiocytoma” being replaced by “UPS”. In 2010 an analysis of multiple sarcoma expression databases using a 170-gene predictor, re-classified most MFH and “not-otherwise-specified” (NOS) tumors as liposarcomas, leiomyosarcomas or fibrosarcomas. Interestingly, some of the classifier genes are potential molecular therapeutic targets including Insulin-like growth factor 1 (IGF-1), Peroxisome proliferator-activated receptor γ (PPARγ), Nerve growth factor β (NGF β) and Fibroblast growth factor receptor (FGFR).

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.

Atypical lipomatous tumor/well-differentiated liposarcoma: what is it?

Liposarcoma (LPS) is the most common soft tissue sarcoma, frequently found in the thigh and retroperitoneum. LPS is commonly classified into well-differentiated LPS and dedifferentiated LPS. Histologic subtype, tumor location, and completeness of surgical resection are important prognostic indicators for LPS. Magnetic resonance imaging best characterizes extremity lesions, whereas computed tomography is most often used for intra-abdominal and retroperitoneal tumors. Surgical resection is the mainstay of treatment. Adjuvant radiation is considered for close margins. Survival for extremity tumors is favorable. However, difficulty in obtaining wide margins in the retroperitoneum predisposes to local recurrence and, ultimately, death from unresectable disease.

Paclitaxel-eluting polymer film reduces locoregional recurrence and improves survival in a recurrent sarcoma model: a novel investigational therapy

BACKGROUND

Locoregional recurrences occur in up to 50% of patients after macroscopically complete (R0/R1) resections of abdominal, pelvic, and retroperitoneal sarcomas. Efficacy of a drug-eluting polymer film in reducing locoregional recurrence rates was assessed in a murine recurrent sarcoma model.

METHODS

Poly(glycerol monostearate-co-caprolactone) polymer films were synthesized with and without 300 μg paclitaxel (Pax-film and unloaded film). Cytotoxicity was assessed against CS-1 (human chondrosarcoma) cells in vitro and in vivo in nude mice. Following R0/R1 resection of primary subcutaneous tumors, mice were blindly randomized to: (1) Pax-film implant, (2) unloaded film implant, (3) paclitaxel 300 μg IV (Pax IV), or (4) no other therapy ("untreated"). Locoregional recurrence, overall survival (OS), and tumor mitotic index were evaluated.

RESULTS

Pax-films, but not unloaded films, reduced CS-1 viability in vitro for >50 days (P < 0.001). In vivo, locoregional recurrence was observed in 2 of 12 Pax-film mice (17%), 9 of 13 unloaded film mice (69%), 8 of 9 Pax IV mice (89%), and 7 of 8 untreated mice (88%) (P < 0.01). Median OS was 81, 64, 48, and 56 days, respectively. Paclitaxel levels in local tissues were 50- to 300-fold greater in Pax-film mice compared with Pax IV mice. Tumor mitotic index adjacent to Pax-films was significantly lower than adjacent to unloaded films.

CONCLUSIONS

Tumor bed implantation of Pax-films after R0/R1 resection is superior to Pax IV as evidenced by reduced locoregional recurrence and improved OS in a murine recurrent sarcoma model. Continuous local drug exposure via polymer films represents a potentially novel approach for treatment of locally aggressive sarcomas.

Management of high-grade retroperitoneal liposarcomas: personal experience

Sarcomas are uncommon malignant tumors arising from mesenchymal tissue, accounting for approximately 10% of soft-tissue sarcomas and less than 1% of all malignant neoplasms. The most frequent subtypes of retroperitoneal sarcomas are liposarcoma. Total surgical extirpation appears the only chance for patient cure since medical therapies have shown little efficacy. We have analyzed our series of 32 retroperitoneal liposarcoma that undergone surgical resection and with at least 5 years of follow-up. We have included 21 patients who underwent a complete resection (R0) and 6 patients who underwent an incomplete resection (R1). However, the operation's goal was a complete tumor resection with tumor-free resection margins. The 5-year survival was 85.7% when we performed a R0 resection, while it was 33.3% when we performed a R1 resection with a significant statistical difference (p = 0.02). Surgery is the gold standard for treatment of liposarcoma. Despite advances in diagnostic modalities, surgical techniques and the adoption of more aggressive procedure, such disease still has a propensity for local recurrence, even after an apparent complete resection. Therefore, locoregional recurrence remains the main cause of death in patients with a retroperitoneal liposarcoma. Moreover when the tumor recurs locally, the treatment of choice is to remove the recurrence. Our experience shows that a complete resection of primary lesions and further resection of recurrences early detected with CT examination could improve the overall survival of patients with retroperitoneal liposarcoma. Moreover in our series, the patients who undergo R1 resection had a worse prognosis.

Feasibility study of volumetric modulated arc therapy for the treatment of retroperitoneal sarcomas

BACKGROUND

Radiotherapy for retroperitoneal sarcomas remains controversial and a technical challenge considering the threshold of contiguous critical organs tolerance. We performed consecutive RapidArc dosimetric plans in preoperative or postoperative setting.

METHODS

A dosimetric study was carried out from six preoperative (group A) and four postoperative (group B) CT-scans, performed in 7 patients.Prescribed dose was 45 and 50 Gy for groups A and B, respectively. The planning target volume (PTV) was defined as the clinical target volume (CTV) plus 5 mm. The CTV encompassed the gross tumor volume (GTV) plus 10 mm or the tumoral bed. The dosimetric plans were optimized on a RapidArc Eclipse console using the progressive resolution algorithm, PRO version 8.8. Normalization method allowed the coverage of 99% of the PTV by 95% of the dose.

RESULTS

Mean PTV were 2318.5 ± 2223.9 cc [range 348-6198 cc] and 698.3 ± 216.6 cc [range 463 -933 cc] for groups A and B, respectively. Plans were optimized for single arcs in group B and for single or two arcs in group A. The contralateral kidney volume receiving 5 Gy (V5Gy) was 21.5 ± 23.3% [range 0-55%] and 3.1 ± 2.6% [range 0-7.3%] for groups A and B, respectively. The mean dose received by 1% of the kidney (D1%) was 5.6 ± 2.4 Gy [range 3.6 -7.6 Gy] for group A and 5.4 ± 0.7 Gy [range 4.3-6 Gy] for group B. The volume of small bowel excluding the PTV (small bowel-PTV) that received 40 Gy and 30 Gy (V40Gy and V30Gy) in group A were 7.5 ± 4.4% [range 5.4-14.1%] and 18.5 ± 7.1% [range 10-30.4%], respectively.In group B, small bowel-PTV V40Gy and V30Gy were 4.7 ± 3.3% [range 3.3-8%] and 21.6 ± 7.5% [range 9.4-30%] respectively. In a second step, we treated two patients in the postoperative group. Treatment time delivery with one arc was 74 seconds. No severe acute toxicity was observed.

CONCLUSION

RapidArc technology for retroperitoneal sarcomas showed acceptable dosimetric results in preoperative or postoperative clinical situation. From the first treated patients, acute tolerability was good to excellent.

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.

Radiation therapy in addition to gross total resection of retroperitoneal sarcoma results in prolonged survival: results from a single institutional study

Purpose. Typical treatment of retroperitoneal sarcomas (RPSs) is surgery with or without radiation therapy for localized disease. With surgery alone, local failure rates are as high as 90%; this led to radiation therapy playing an important role in the treatment of RPSs. Methods. Thirty-one patients with retroperitoneal sarcoma treated with gross total resection and radiation therapy make up this retrospective analysis. Nineteen were treated preoperatively and 12 postoperatively (median dose, 59.4 Gy)—sixteen also received intraoperative radiation therapy (IORT) (median dose, 11 Gy). Patients were followed with stringent regimens, including frequent CT scans of the chest, abdomen, and pelvis. Results. With a median follow-up of 19 months (range 1–66 months), the 2-year overall survival (OS) rate is 70% (median, 52 months). The 2-year locoregional control (LRC) rate is 77% (median, 61.6 months). The 2-year distant disease free survival (DDFS) rate is 70% (median not reached). There were no differences in radiation-related acute and late toxicities among patients treated pre- versus postoperatively, whether with or without IORT. Conclusions. Compared to surgery alone, neoadjuvant or adjuvant radiation therapy offers patients with RPS an excellent chance for long-term LRC, DDS, and OS. The integration of modern treatment planning for external beam radiation therapy and IORT allows for higher doses to be delivered with acceptable toxicities.

Long-Term Outcomes After Radiotherapy for Retroperitoneal and Deep Truncal Sarcoma

PURPOSE

To determine the long-term outcomes after multimodality treatment of retroperitoneal, pelvic, and deep truncal sarcomas and to identify the factors associated with local control (LC), distant metastasis (DM), and overall survival (OS).

METHODS AND MATERIALS

A total of 85 patients with retroperitoneal, pelvic, and deep truncal sarcomas were treated with radiotherapy (RT) between 1987 and 2005. A retrospective analysis of LC, DM, and OS was conducted using log-rank and Cox regression statistical methods.

RESULTS

The 2- and 5-year LC, DM, and OS rates were 66% and 51%, 38% and 58%, and 70% and 34%, respectively. Negative surgical margins and a higher radiation dose were associated with greater LC rates on both univariate and multivariate analyses, and female gender was significantly associated with greater LC on multivariate analysis only. None of the analyzed risk factors was significantly associated with DM, although patients with high-grade tumors showed a trend toward an increased risk of DM. Gross residual disease after resection and high tumor grade were associated with worse OS rates on univariate and multivariate analyses, and male gender was significantly associated with worse OS on multivariate analysis only. A time-dependent analysis of LC in relation to DM demonstrated that patients with local failure had a hazard ratio of 19.7 for DM compared with patients without local failure (p < 0.0001). Of the 85 patients, 5 and 8, respectively, had clinically significant acute and late toxicity.

CONCLUSION

The results of this study emphasize the importance of LC in patients with retroperitoneal sarcoma. Radiation dose escalation or radiosensitization strategies to enhance LC are warranted.

Primary malignant retroperitoneal tumors: Analysis of a single institutional experience

AIMS

In order to achieve complete resection in the surgical management of retroperitoneal tumors, it is crucial to know the tumor's anatomical location relative to neighboring organs.

METHODS

Forty-nine patients with primary malignant retroperitoneal tumors were divided by tumor location into two groups [upper abdomen (group 1) or lower abdomen (group 2)], and clinicopathological features, tumor recurrence, and patient survival were assessed.

RESULTS

No significant differences in preoperative clinical characteristics existed between two groups, and liposarcoma was the most frequently observed tumor type. The difference in the rates of complete resection between the two groups was not statistically significant (75.9% for group 1 and 85% for group 2). En-bloc combined resection was performed in 52% and 30% of patients in groups 1 and 2, respectively. The local recurrence rate in group 2 (31.3%) was higher than that in group 1 (9.5%), despite the fact that the differences in rates of complete resection and distant recurrence rates (14.3% in group 1 and 12.5% in group 2) between the two groups were not statistically significant. The overall 5-year survival rates were 67.9% for group 1 and 43.2% for group 2 (p=0.038). The 5-year survival rate of patients with tumors smaller than 10 cm was 78.4%, while that of patients with tumors larger than 10 cm was 38.1% (p=0.017). The 5-year survival rate after complete excision was 61%, whereas that after incomplete resection or biopsy only was 40.0% (p<0.0001).

CONCLUSIONS

An upper abdominal tumor location is a positive prognostic factor even if small tumor size (<10 cm) and complete resection of the tumor are still more important factors to improve outcome in patients with malignant primary retroperitoneal tumors. Because complete resection was shown to be the most important prognostic factor, an aggressive and careful surgical approach is recommended for the treatment of such tumors.

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

INTRODUCTION

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

METHODS

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

RESULTS

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

CONCLUSIONS

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

STATISTICS

Median (interquartile range).

Dosimetric comparison of helical tomotherapy treatment and step-and-shoot intensity-modulated radiotherapy of retroperitoneal sarcoma

PURPOSE

To compare step-and-shoot intensity-modulated radiation therapy (SAS-IMRT) and helical tomotherapy (Tomo) dosimetry plans for patients who have received adjuvant radiation therapy for retroperitoneal sarcomas (RSTS).

METHODS AND MATERIALS

A retrospective review was performed for seven patients who received either SAS-IMRT or Tomo as adjuvant radiation therapy for RSTS. In each case, a treatment plan of the other modality was generated so that SAS-IMRT and Tomo could be compared.

RESULTS

The average percentage of clinical target volume (CTV) that received less than the prescription dose was 1.4% for Tomo compared to 3.8% for SAS-IMRT. Both SAS-IMRT and Tomo plans provided comparable and significant reductions in volume of small bowel receiving greater than 45 Gy compared to simple opposing standard radiation fields. For the ipsilateral kidney, Tomo significantly reduced the volume of kidney that received at least 15 Gy (average 22% for Tomo vs. 56% for SAS-IMRT).

CONCLUSION

Both SAS-IMRT and Tomo can encompass the large CTV often required for patients with RSTS, although Tomo provides superior dose uniformity. Both SAS-IMRT and Tomo can minimize the volume of small bowel receiving greater than 45 Gy. Tomo was superior to SAS-IMRT in minimizing the volume of ipsilateral kidney irradiated to greater than 15 Gy when the CTV is adjacent to a kidney. Dose escalation and target margin expansion may thus become realistic possibilities.

Retroperitoneal sarcomas: Combined-modality treatment approaches

Retroperitoneal sarcomas (RPS) are rare tumors, accounting for approximately 15% of soft tissue sarcomas. Surgical resection of localized tumors with gross and microscopically negative margins remains the standard of care. However, because RPS are frequently large and locally advanced, resections are often incomplete, resulting in local recurrence. Investigators are evaluating combined-modality therapies to improve local control and disease-specific survival. This review outlines current concepts and evolving treatment strategies in the diagnosis, staging, and management of RPS.

EFFECT OF RESECTION AND OUTCOME IN PATIENTS WITH RETROPERITONEAL SARCOMA

BACKGROUND

A consecutive series of 47 patients with retroperitoneal sarcoma (RPS) were resected and prospectively followed.

METHOD

Between July 1994 and March 2005, 47 patients (24 men, 23 women; mean age, 56 years; range, 17-82 years) were evaluated.

RESULTS

A total of 23 patients had primary RPS and 24 patients had recurrent RPS. A total of 30 out of 47 patients (64%) underwent removal of contiguous intra-abdominal organs. The peroperative mortality was nil and significant preoperative complications occurred in eight cases only (17%). High tumour grade and incomplete resection were significant variables for a worse survival in all 47 patients, both in the univariate and multivariate analyses (P = 0.008 and P = 0.016, respectively). Among 28 radically resected patients, only histological grade affected overall survival (90% 5-year survival for low-grade tumour vs 26% 5-year survival for high-grade tumour; P = 0.006) with a similar effect noted for disease-free survival.

CONCLUSIONS

Histological grade was the only factor that affected overall and disease-free survival for RPS tumours. An aggressive surgical approach in both primary and recurrent RPS is associated with long-term survival.

Primary and recurrent retroperitoneal soft tissue sarcoma: prognostic factors affecting survival

BACKGROUND AND OBJECTIVES

To analyze treatment and survival in 34 patients (28 resected) with primary or recurrent retroperitoneal sarcoma (RPS).

METHODS

Between July 1994 and January 2001, 34 patients (15M, 19F; mean age: 56 years, range: 25-77) were evaluated. Complete resection was defined as removal of gross tumor with histologically confirmed clear resection margins.

RESULTS

Twenty-eight out of 34 patients (82%) (15 were affected by primary RPS, and 13 by recurrent RPS), underwent surgical exploration. Twenty-three patients had a grossly and microscopically complete resection, (3 having a grossly incomplete resection and 2 patients with a grossly complete resection having histologically involved resection margins). Twenty-one out of 28 patients (75%) underwent removal of contiguous intra-abdominal organs. Preoperative mortality was nil, and morbidity occurred in six cases only (21%). High tumor grade results a significant variable for a worse survival in all 28 patients (100% 5 years survival for low grade vs. 0% for high grade; P = 0.0004). Amongst completely resected patients, only histologic grade and peroperative blood transfusions affected disease-free survival (P = 0.04 and P = 0.05, respectively).

CONCLUSIONS

An aggressive surgical approach in both primary and recurrent RPS is associated with long-term survival.

Surgery Combined With Intraoperative Brachytherapy in the Treatment of Retroperitoneal Sarcomas

BACKGROUND

The purpose of this study was to analyze the results of treatment of retroperitoneal soft tissue sarcomas (RSTS) by surgery combined with intraoperative brachytherapy (IOBRT).

METHODS

Seventy adult patients with RSTS were considered for combined treatment (surgery plus IOBRT) between June 1998 and February 2004. There were 64 (91%) recurrent tumors, and 93% of tumors exceeded 5 cm. IOBRT was performed with high-dose-rate Gammamed 12 with iridium 192 (IOBRT time range, 20-87 minutes; median, 56 minutes).

RESULTS

After intraoperative re-evaluation, 24 patients (34%) were found to be ineligible for IOBRT because of multiple intraperitoneal recurrences, macroscopically nonradical resection, poor general condition, and technical aspects. Thirty-seven patients underwent IOBRT immediately after surgery during the same general anesthesia procedure. Nine patients underwent delayed IOBRT within 1 to 3 days after the primary operation. Ten (21.5%) of 46 patients underwent reoperation because of surgical complications. One patient died in the postoperative period. After IOBRT, 24 patients (52%) underwent adjuvant external beam radiotherapy (EBRT) to a total dose of 50 Gy. Over a median follow-up time of 20 months, the estimated 5-year overall survival and local recurrence-free survival rates in IOBRT patients were 55% and 51%, respectively. Application of adjuvant EBRT showed a favorable local control rate.

CONCLUSIONS

The scheduled combined treatment (surgery plus IOBRT) was possible to perform in 66% of RSTS cases that received surgical treatment. The complication rate was high, but we consider it acceptable because of the necessity for extensive aggressive surgical treatment in regionally advanced RSTS. EBRT seems to be an indispensable part of treatment that provides better local control.

Retroperitoneal sarcoma

BACKGROUND

No population-based studies of retroperitoneal sarcoma (RPS) have been conducted, and the use and timing of adjuvant radiotherapy for RPS is controversial. The objective of this study was to examine the incidence and treatment of RPS, specifically regarding the use of adjuvant radiotherapy.

METHODS

The Surveillance, Epidemiology, and End Results (SEER) database was used to evaluate the incidence of RPS over a 29-year period (1973-2001). The rate of surgery, the rate and timing of adjuvant radiotherapy, and the influence of demographic factors on treatment were evaluated.

RESULTS

A total of 2348 cases of RPS were identified. The mean annual incidence of RPS was 2.7 cases per 10(6) persons and did not change significantly over time (2.6 in 1973 vs. 2.8 in 2001; P = .92). Most patients (1654; 70.4%) underwent surgical resection. Radiotherapy was used in 428 patients (25.9%) who underwent surgery; radiation was given postoperatively in 366 (85.5%), preoperatively in 20 (4.7%), and intraoperatively or unknown in 42 (9.8%). Patients who received any adjuvant radiotherapy were on average 5 years younger than those who underwent surgery alone (P < .0001). Radiotherapy was more commonly used among whites than African Americans (25.8% vs. 16.7%; P = .02) and there was significant variation in the use of adjuvant radiotherapy by geographic location (P = .003). On multivariate analysis, race (P = 0.004), age (P < .0001), and geographic location (P = .006) were independently associated with the use of adjuvant radiotherapy.

CONCLUSION

The incidence of RPS, a rare disease, appears stable. Most patients who undergo surgery do not receive any adjuvant radiotherapy, and very few receive preoperative radiotherapy. Differences in adjuvant radiotherapy use related to demographic and geographic factors suggest that at least some treatment variations reflect differences in individual and institutional practice patterns.

Estudo da morbimortalidade cirúrgica, da sobrevida e dos fatores prognósticos dos pacientes portadores de sarcomas primários do retroperitônio

OBJETIVO: Avaliar a morbimortalidade, sobrevida e os fatores prognósticos dos sarcomas primários do retroperitônio. MÉTODO: Análise retrospectiva de 59 pacientes com sarcoma de retroperitônio, operados na Seção de Cirurgia Abdomino-Pélvica do Instituto Nacional de Câncer no período de junho de 1992 a julho de 2003. RESULTADOS: As queixas mais comuns foram dor abdominal e massa abdominal. A taxa de ressecabilidade foi de 74,57% e a de radicalidade entre os ressecados de 48,88%. Houve dois óbitos pós-operatórios (3,38%) e 12 complicações pós-operatórias (20,33%). Os leiomiossarcomas e os lipossarcomas foram os mais incidentes. O grau de diferenciação tumoral mais freqüente foi o G3 (38,98%) e o diâmetro tumoral médio, de 20,4 cm. A sobrevida global foi de 49% em dois anos e 20% em cinco anos, e a mediana de sobrevida livre de doença foi de 23 meses. À análise univariada, o diâmetro do tumor (> ou < = 12 cm), o grau de diferenciação tumoral ([G1 + G2] X [G3 + G4]), a ressecção radical (R0) ou paliativa (R1 + R2), a hemotranfusão no ato operatório e a re-ressecção, mesmo que paliativa, nos casos de recidiva ou persistência de doença (n = 52), foram significativos para sobrevida (p = 0,0267, 0,048, 0,0001, 0,022 e 0,0003, respectivamente). CONCLUSÃO: No momento, somente o diagnóstico precoce, a cirurgia radical R0, a ausência de hemotransfusão intra-operatória e a re-ressecção nos casos de recidiva ou persistência de doença possibilitarão a sobrevida a longo prazo.

Adjuvant Radiation Therapy for Resectable Retroperitoneal Soft Tissue Sarcoma

BACKGROUND

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

METHODS

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

RESULTS

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

CONCLUSION

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

Pelvic exenteration and sphincter preservation in the treatment of soft tissue sarcomas

BACKGROUND

Pelvic sarcomas are rare and there are very few effective therapeutic alternatives. A complete resection is considered the main factor associated to a good prognosis, which justifies the employment of a pelvic exenteration (PE) in selected cases.

METHODS

Between 1980 and 2000, 96 PE were performed, nine of which were for sarcomas. The clinical characteristics, surgical and anatomopathological aspects and the patients' evolution were described.

RESULTS

The median follow-up time was 24 months (ranging from 1 to 57 months). In relation to the sphincters preservation, at least one sphincter was preserved in five patients. There were two post-operative deaths. In the last follow-up, six patients were alive without any evidence of the disease.

CONCLUSION

Pelvic exenterations should be performed for the treatment of selected cases of locally advanced pelvic sarcomas. Sphincter preservation may be performed, provided that oncological resection principles are obeyed.

Retroperitoneal sarcoma: 25 years of experience with aggressive surgical treatment at the Institute of Oncology, Ljubljana

BACKGROUND AND OBJECTIVES

Retroperitoneal sarcomas are rare malignant tumors with an aggressive course of disease and high local recurrence rate. Local disease is the main cause of death. A retrospective study was undertaken to evaluate the results of aggressive surgical treatment in a series of patients of primary and recurrent retroperitoneal sarcomas.

PATIENTS AND METHODS

From 1975 to 2000, 155 patients with retroperitoneal tumors were operated on at the Institute of Oncology, Ljubljana. Patients with fibromatosis and children less than 16 years were excluded from further calculation. Out of the rest 139 patients, 102 patients had localized retroperitoneal sarcoma, and 37 patients had retroperitoneal sarcoma with distant metastases Leiomyosarcoma was the most common type of histology, followed by liposarcoma and schwannoma. Their referral status was as follow: 56 had primary sarcoma, 20 residual sarcoma after operation elsewhere and 26 already recurrent sarcoma. Our treatment approach was aggressive. We removed surgically primary tumor, recurrent sarcoma and metastases, whenever possible. To this end, we performed, 235 operations for retroperitoneal sarcomas on 139 patients (up to 8 operations on 1 patient).

RESULTS

Complete resection was done in 97 of 102 patients with localized sarcoma (resectability rate 95%); in 55 patients, R0 resection was made, in 42 patients, R1 resection, in 3 patients, debulking procedure, and in 2 patients biopsy alone. In 118, patients at least one organ was resected completely or partially en bloc with tumor. The 5-, 10-, and 15-year survivals of patients with localized sarcoma were 52%, 36%, and 22%, respectively. The 5-year survival of patients with metastases was 12% (P = 0.0002), the 5- and 10-year survival rates of patients with R0 resection were 75% and 64%, respectively, and of those with R1 resection, 25% and 8%, respectively (0 < 0.00001). High tumor grade was associated with poor survival. The 5-year local recurrence rate of patients with primary sarcoma and of those with locally recurrent sarcoma was 37% and 71%, respectively (P = 0.04). After the first local recurrence, the 5- and 10-year survival rates were 42% and 26%, after the second local recurrence 45% and 22%, after the third local recurrence 43% and 11%, and after the fourth local recurrence 51% and 17%, respectively.

CONCLUSION

Complete surgical resection without microscopic residuum and contamination is likely to offer the best chances for long-term survival. Until there are no other treatment modalities, aggressive surgery for recurrent sarcoma is recommended.

Surveillance strategies for patients following surgical resection of soft tissue sarcomas

PURPOSE OF REVIEW

To examine the factors predictive of recurrence for soft tissue sarcomas, the role of salvage therapy, and the data in support of current surveillance strategies.

RECENT FINDINGS

There are multiple primary tumor characteristics and other factors that can stratify patients into low- or high-risk groups for developing recurrent disease. The available data also support a limited role for salvage therapy in the setting of isolated local recurrence or distant metastases. The use of routine chest computed tomography as opposed to conventional chest x-ray for pulmonary surveillance is costly and provides little additional benefit if the risk for lung metastases is low. When examined scientifically, standard laboratory studies and surveillance imaging of the primary tumor site for extremity soft tissue sarcomas add little to the detection of recurrent disease. In addition to predictive variables, physician experience and opinion influence surveillance strategies.

SUMMARY

For soft tissue sarcomas, patient education and office visits with thorough history and physical examination will detect the vast majority of recurrent disease. Routine surveillance imaging is only of significant benefit if the risk for asymptomatic recurrence is high or if other factors make clinical assessment difficult. There is no benefit to basic laboratory studies in standard follow-up regimens.

Operative management of primary retroperitoneal sarcomas: a reappraisal of an institutional experience

OBJECTIVE

To review our recent experience with primary retroperitoneal sarcomas, determine prognostic factors for disease recurrence and patient survival, and compare them to our previous results.

BACKGROUND

Medical therapies have shown little efficacy in the management of retroperitoneal sarcomas, making total surgical extirpation the best chance for patient cure.

METHODS

The case histories of all patients operated upon for retroperitoneal sarcomas between January 1983 and December 1995 were retrospectively reviewed.

RESULTS

Ninety-seven patients underwent attempted surgical resection of a primary retroperitoneal sarcoma. There were 54 (56%) men and 43 (44%) women, with a mean age of 59 years. Seventy-six (78%) patients underwent gross total resection, 13 (14%) had residual disease, and 8 (8%) underwent biopsy only with an actuarial 1-year survival of 88%, 51%, and 47%, respectively (P = 0.001). The actuarial 5- and 10-year survivals for patients who underwent gross total resection were 51% and 36%, respectively. Thirty-three patients (43%) developed locoregional recurrence, and 20 patients (26%) developed distant metastases at a median time of 12 months. The cumulative probability at 5 years was 44% for locoregional recurrence and 29% for distant metastases. On univariate analysis, factors associated with improved survival were complete resection of the tumor (P = 0.001), nonmetastatic disease at presentation (P = 0.01), low-grade tumors (P = 0.02), liposarcomas (P = 0.003), and no disease recurrence (P = 0.0001). Contrary to previous reports, the histologic subtype (P = 0.04) was the only significant factor predicting survival on multivariate analysis.

CONCLUSIONS

Compared with our earlier experience, the rates of complete resection and overall survival have improved. Local control continues to be a significant problem in the management of retroperitoneal sarcomas. Because new surgical options for this problem are limited, further outcome improvement requires novel adjuvant therapies.

Histologic subtype and margin of resection predict pattern of recurrence and survival for retroperitoneal liposarcoma

OBJECTIVE

The aim of this study was to determine the pattern of recurrence and prognostic significance of histologic subtype in a large series of patients with primary retroperitoneal liposarcoma.

SUMMARY BACKGROUND DATA

Classification of liposarcoma into subtypes, based on morphologic features and cytogenetic aberrations, is now widely accepted. Previous studies have shown that high histologic grade and incomplete gross resection are the most important prognostic factors for survival in patients with retroperitoneal sarcoma and suggest that patients with liposarcoma have a 3-fold higher risk of local recurrence compared with other histologies.

METHODS

A prospective database was used to identify 177 patients with primary retroperitoneal liposarcoma treated between July 1982 and June 2002. Histology at primary presentation was reviewed by a sarcoma pathologist and subtyped into 4 distinct groups according to strict criteria. The influence of clinicopathological factors on local recurrence, distant recurrence, and disease-specific survival was analyzed.

RESULTS

Of 177 patients with primary retroperitoneal liposarcoma operated on for curative intent, 99 (56%) presented with well-differentiated, 65 (37%) with dedifferentiated, 9 (5%) with myxoid, and 4 (2%) with round cell morphology. The tumor burden was determined by the sum of the maximum tumor diameters. The median tumor burden was 26 cm (5-139). Median follow-up time for 92 (52%) surviving patients was 37 (mean, 0.5-192) months. Multivariate analysis showed that dedifferentiated liposarcoma subtype was associated with a 6-fold increased risk of death compared with well-differentiated histology (P < 0.0001). In addition to histologic subtype, incomplete resection (P < 0.0001), contiguous organ resection (excluding nephrectomy; P = 0.05), and age (P = 0.03) were important independent prognostic factors for survival in retroperitoneal liposarcoma. Retroperitoneal dedifferentiated liposarcoma was associated with an 83% local recurrence rate and 30% distant recurrence rate at 3 years.

CONCLUSIONS

The histologic subtype and margin of resection are prognostic for survival in primary retroperitoneal liposarcoma. Dedifferentiated histologic subtype and the need for contiguous organ resection (excluding nephrectomy) was associated with an increase risk of local and distant recurrence. Nephrectomy may be needed to achieve complete resection, but has no measurable influence on disease specific survival.

Retroperitoneal sarcomas

Retroperitoneal sarcomas comprise a rare, heterogeneous group of neoplasms. Routine workup should include the patient's medical history, a physical examination, and helical CT of the abdomen and pelvis, with selective use of MRI and preoperative tissue sampling. The primary treatment is complete surgical resection with a rim of normal tissue. The role of adjuvant therapy is evolving and at present should not be used outside the investigational setting.

Most malignant fibrous histiocytomas developed in the retroperitoneum are dedifferentiated liposarcomas: a review of 25 cases initially diagnosed as malignant fibrous histiocytoma

Forty-four samples from 25 cases of retroperitoneal sarcoma initially diagnosed as malignant fibrous histiocytoma were histologically reviewed. Immunohistochemistry for mdm2 and cdk4 was performed on 20 cases. Comparative genomic hybridization was performed on 18 samples from 13 patients. Seventeen cases were reclassified as dedifferentiated liposarcoma. Twenty-one of 32 samples from these patients showed areas of well-differentiated liposarcoma, allowing the diagnosis of dedifferentiated liposarcoma. Immunohistochemistry performed in 15 of these cases showed positivity for mdm2 and cdk4. Comparative genomic hybridization analysis performed on 15 samples from 11 of these patients showed an amplification of the 12q13-15 region. Eight cases were reclassified as poorly differentiated sarcoma. Twelve samples from these patients showed no area of well-differentiated liposarcoma. Immunohistochemistry showed positivity for mdm2 and cdk4 in one of six of these patients and showed positivity for CD34 in another one. Comparative genomic hybridization analysis performed on three samples from two of these patients showed no amplification of the 12q13-15 region but showed complex profiles. This study shows that most so-called malignant fibrous histiocytomas developed in the retroperitoneum are dedifferentiated liposarcoma and that a poorly differentiated sarcoma in this area should prompt extensive sampling to demonstrate a well-differentiated liposarcoma component, immunohistochemistry for mdm2 and cdk4, and if possible, a cytogenetic or a molecular biology analysis.

Surgical resection and radiotherapy for primary retroperitoneal soft tissue sarcoma

METHODS AND MATERIALS

Forty-five patients were consecutively treated for primary retroperitoneal soft tissue sarcoma with surgery in combination with radiation therapy in the same institution. The median follow-up time was 53 months (7-108).

RESULTS

Seventeen (38%) patients had clear microscopic margins (R0 resection), 26 patients (58%) had gross complete surgical excision (R1 resection) and two patients (4%) had a macroscopic residual disease (R2 resection). External radiotherapy doses ranged from 40.8 to 59.4 Gy (mean and median: 49 Gy). Seventeen patients underwent intraoperative radiation therapy (IORT). Moreover, 11 patients received chemotherapy. The overall 1-, 2-, and 5-year survival for all 45 patients were 93, 85 and 60%, respectively. The 1-, 2-, and 5-year locoregional relapse-free rate for the whole group was 91, 70 and 40%, respectively. In univariate analysis, quality of surgery was the only variable to show a significant effect for overall survival (P=0.0386) and for local control (P=0.0059). Tumor size and tumor grade had no statistically significant effect. For the patients receiving IORT+external beam radiation therapy, no difference was observed for survival or locoregional control. The most frequent acute side effects treatment complications were radiation-induced nausea or vomiting (42%) and moderate enteritis (30%). Significant late morbidity was observed for two patients.

CONCLUSIONS

This study confirms the feasibility of external postoperative radiotherapy with an acceptable level of toxicity. However, the high rate of local relapses (especially in field of radiation) does not demonstrate the usefulness of radiotherapy at the level of dose used and further preferably randomized studies should be planned.

Aggressive resection of retroperitoneal sarcoma is superior to simple excision: an animal study using a novel model for retroperitoneal sarcoma

BACKGROUND AND OBJECTIVES

Retroperitoneal sarcomas constitute a difficult management problem. The need for, and extent of, aggressive surgery continues to be debated. The aim of our study was to compare the impact of radical en bloc resection of retroperitoneal sarcoma with complete resection of the tumor alone in a rat model.

METHODS

Under laparoscopic guidance, a fibrosarcoma cell line suspension was injected into the left paranephric space of a rat, resulting in the development of a macroscopic retroperitoneal tumor. Ten days after inoculation, 50 rats were randomized into three groups: (1) local resection, (2) radical resection, and (3) follow-up only. Groups 1 and 2 were further randomized for sacrifice 1 month after surgery or were followed up for 2 months.

RESULTS

Local recurrence: 46% of group 1, while none in group 2 developed local recurrence during the same follow-up period (P = 0.02). Survival: 33% of group 1 were alive after 2 months, as compared with 54.5% of group 2. (P = 0.04). All rats in the control group died within <25 days.

CONCLUSIONS

Our results suggest that aggressive en bloc resection of retroperitoneal sarcomas with adjacent viscera, even when macroscopically uninvolved with disease, has an advantage over complete local resection alone.

Retroperitoneal sarcomas: combined modality treatment approaches

Retroperitoneal soft tissue sarcomas are rare tumors estimated to account for 15%of all patients with soft tissue sarcoma seen in referral populations. The standard of care for patients with localized, resectable retroperitoneal sarcomas is surgical resection with gross and microscopically negative margins. However, owing to the large size and locally advanced nature of these tumors, this goal is difficult to achieve in most patients. As a result, the disease is characterized by a high propensity for local recurrence and a grade-specific risk for distant metastasis. Over the past decade, there has been considerable research into combined modality treatment of these tumors. The present report outlines current concepts relating to the diagnosis, staging, and management of retroperitoneal sarcomas. Emphasis is placed on evolving combined modality treatment approaches and current investigational strategies.

Prognostic factors predicting survival in the treatment of retroperitoneal sarcoma

METHODS

Retroperitoneal soft tissue sarcomas are rare tumours. The management of these tumours has been difficult because of low resectability and a high recurrence rate. A retrospective review of a prospectively compiled database of 32 consecutive patients with retroperitoneal sarcomas treated at Oulu University Hospital between 1977 and 1996 was performed.

RESULTS

The resectability rate of primary tumours was 75%, and 44% of the patients underwent radical resection. The recurrence rate after radical resection was 57% and the resectability rate for recurrent tumours after radical primary operation, 50%. The actuarial overall 5-year survival rate was 31%, 10-year survival rate 19% and median survival 36 months. In univariate analysis the principal factors associated with prognosis were radical resection, recurrent disease, pre-operative loss of weight and histological tumour grade. Complete excision of the primary tumour was the only significant predictor of survival in multivariate analysis.

CONCLUSIONS

Complete resection of retroperitoneal sarcoma continues to be the most important prognostic factor. The inefficiency of adjuvant therapy, the high recurrence rate and the very low chance of curing the patient after recurrence make the prognosis of these patients poor.

Prognostic factors in retroperitoneal sarcomas: ploidy of DNA as a predictor of clinical outcome

BACKGROUND AND OBJECTIVES

Radical surgery is the best mode of treatment of retroperitoneal sarcomas (RS); however, common recurrences are unpredictable.

METHODS

For the better understanding of outcomes and possibilities of treatment retrospective analysis of different factors, including DNA content, was performed based on 70 patients.

RESULTS

Leiomyosarcoma and liposarcoma were most common histologic types of classified sarcomas. Different kinds of resection were successfully performed in 51 patients (73%) and 35 of their available DNA specimens were analyzed. The actuarial 5- and 10-year survival rates in the resection group were 53% and 40%, respectively, with the median survival of 57 months. Patients with diploid resected tumors had a better 10-year survival rate (58%), than those patients with aneuploid tumors (25%,)--P<0.005. Those patients with low-grade sarcomas had a significantly longer survival than those with high-grade sarcomas (10-year survival rate: 44% compared to 29%). In the univariate analysis, adjuvant therapy, type of histology, type of surgery, location of tumor, and S-phase fraction had no influence on survival. In the multivariate analysis (Cox), only ploidy was an independent prognostic variable. Relative risk of death was over three times higher for aneuploid than for diploid tumors.

CONCLUSION

Tumor ploidy should be analyzed in every case of retroperitoneal sarcoma for better assessment of prognosis and possible indication for adjuvant therapy.