Primary Retroperitoneal Sarcoma Research Articles

A multivariate analysis of a series of 382 primary retroperitoneal sarcomas (RPS)

10065 Background: A national retrospective study was conducted by the French Association of Surgery on primary RPS in order to define the best type of surgery and determine prognostic factors for abdominal recurrence and patient survival. There is still no consensus concerning the precise value of the extent of surgery and additional treatment modalities. Methods: Types of surgery were classified as: “systematic complete resection”, which is a systematic or partial resection of non-involved contiguous organs to achieve wide margins, “contiguously involved organ resection” and “simple complete resection”, a resection of the tumor with grossly negative margins. Survival was determined with the Kaplan-Meier method. Univariate and multivariate prognostic analyses were performed using logrank test and Cox model. Results: Data of 382 pts operated between 1985 and 2005 were retrospectively reviewed. Median age was 57 years (range 14–87). Median tumor size was 18 cm. Systematic complete resection, contiguously involved organ resection and simple complete resection were performed for 134 (35%), 153 (40%) and 87 (23%) pts, respectively. Eight pts (2%) had a biopsy without resection and 45 pts (12%) had macroscopic residual disease. Tumor was spilled during surgery for 76 pts (20%). Systematic complete resection and no spilling of the tumor were highly correlated with the number of pts operated by center (p-values <10-4). Histologic negative margins (136 pts, 36%) were highly correlated with systematic complete resection (p-value <10-4). Chemotherapy and radiotherapy were given to 135 (35%) and 122 pts (32%). Median survival was 6 years whereas median time to abdominal recurrence and metastasis were 4 and 15 years, respectively. On multivariate analysis, pre op biopsy, low grade, no spilling of the tumor, negative margins and number of pts operated by center were the significant factors predicting abdominal recurrence control whereas low grade, no spilling of the tumor and no macroscopic residual disease significantly predicted better overall survival. Conclusions: Tumor grade and quality of surgery were the two main prognostic factors for abdominal recurrence and overall survival. Surgical experience of these rare tumors and systematic complete resection decreased abdominal recurrence rate. No significant financial relationships to disclose.

Giant Retroperitoneal Sarcomas: A Single Institution Experience

Retroperitoneal sarcomas (RS) are a rare group of malignant soft-tissue tumors; due to the flexibility of the retroperitoneum, they generally grow to a large size before becoming symptomatic, often involving surrounding structures. Therefore, the surgeon is frequently compelled to perform large excisions. The aim of this study is to assess clinical and pathological factors affecting prognosis in patients with RS who underwent surgical treatment, comparing giant forms (size > or = 25 cm) with smaller ones (size < 25 cm). The hospital records of 73 consecutive patients who underwent surgical exploration for primary RS at our unit between 1984 and 2003 were reviewed. Statistical analysis of factors influencing overall and disease-free survival was performed including both the whole group of patients and only those who underwent complete surgical resection. Giant RS showed a lower resectability rate than smaller forms (54.2% vs. 84.2%, P = 0.005). In the group with complete surgical excision (51 out of 73), patients with giant RS had a higher rate of adjacent organ resection compared with the smaller ones (84.2% vs. 53.1%, P = 0.023). Tumor size did not influence prognosis: after complete resection, 5-year overall survival was 60.9% and 56.3% for giant RS and smaller forms respectively, while 5-year disease-free survival was 54.3% and 48.3% for the two groups respectively. Advanced stage, incomplete gross surgical resection, higher tumor grade, non-liposarcoma histology and microscopic infiltration of margins were found to be significantly negative prognostic factors. The present study confirms the importance of aggressive surgical management for RS, in order to offer these patients the best chance of long-term survival.

Retroperitoneal soft tissue sarcoma

Background Retroperitoneal sarcomas are rare malignant tumours with aggressive course of disease and high local recurrence rate. The evaluation and treatment of retroperitoneal sarcomas are challenging because the tumours are relatively rare and frequently present with advanced disease in an anatomically complex location. We analyzed the treatment and survival in 96 patients with primary or recurrent retroperitoneal sarcoma (RPS).

Analysis of prognostic factors associated with primary retroperitoneal sarcoma.

To explore the prognostic factors associated with recurrence and survival in patients with retroperitoneal sarcoma. A retrospective analysis was performed in 77 patients who were affected by primary Retroperitoneal Sarcoma and treated with surgery between January 1980 and December 2005. 57 cases developed local recurrence and 3 had metastases after surgery. The overall recurrence rate was 74%. Median time between initial surgery and recurrence was 14.8 months (range 3.2-99.6). There were 27 patients who died of disease and 5 for other reasons. The median survival time was 42.5 months (range 3.6-180.4). The overall 5-year and 10-year survival rates were 61.7 and 43.9%,respectively. The 5-year and 10-year relapse-free survival rates were 22.7 and 16.8%, respectively. In univariate analysis, female sex (p = 0.047), tumor size < 15 cm (p = 0.045), complete tumor resection (p < 0.001), no adjacent visceral involvement (p = 0.012) and no local recurrence (p = 0.001) were found to have prognostic significance for a decreased risk of tumor-related mortality. When subjected to Cox multivariate analysis, the only factor found to decrease the risk of tumor-related mortality was complete tumor resection (p = 0.001). Incomplete tumor resection (p = 0.019) and high tumor grade (p = 0.042) were associated with an increased local recurrence rate. Complete surgical resection at the time of primary tumor presentation affords the best chance for local control and long-term survival. Patients with high-grade tumor present a significant risk of local relapse after surgery.

Long-term prognosis of primary retroperitoneal soft tissue sarcoma

Aims To evaluate the result of treatment and long-term outcome of a population-based cohort of patients with retroperitoneal soft tissue sarcoma (RSTS). Methods Between 1 January 1989 and 1 January 1994, 143 patients diagnosed as having primary RSTS were selected from a national pathology database (PALGA) in the Netherlands. In this population-based group of patients, the result of surgery, overall survival (OS) and disease-free survival (DFS) were analysed as well as factors affecting OS and DFS. Median follow-up was 10.2 years. Results Operative treatment resulted in a complete tumour resection in 55% of the patients ( n = 78), low- and intermediate-grade tumours were more often completely resected than high-grade tumours ( P = 0.016). Five- and 10-year cumulative OS was 39% and 21%, respectively, while DFS was 22% and 17%, respectively. In a multivariate analysis low malignancy grade ( P = 0.017) and a complete tumour resection ( P < 0.001) were associated with better OS. Conclusions Complete tumour resection and low malignancy grade were independent favourable prognosticators. However, these factors were related too, since surgical success was influenced by malignancy grade.

Synovialosarcome rétropéritonéal révélé par un choc hémorragique

Primary retroperitoneal synovial sarcoma is a rare malignant neoplasm that typically arises in young adults. We report here an unusual presentation of this tumor during hemorrhagic shock and retroperitoneal hematoma. A 31-year-old man was admitted complaining of acute violent pain of the right lower abdominal quadrant. Physical examination was normal. The computed tomography scan showed a heterogeneous retroperitoneal mass near the iliac bifurcation, with a diameter of 3 cm and spontaneous contrast. The tumor ruptured shortly afterwards and the patient underwent emergency surgery for hemorrhagic shock and retroperitoneal hematoma. No metastases were observed. Although six cycles of doxorubicin and ifosfamide led to initial clinical and tomographic remission, relapse occurred 17 months later. Only 20 cases of primary retroperitoneal synovial sarcoma have been described. They are most often discovered following abdominal pain or anemia. Tumor rupture with retroperitoneal hematoma has not previously been reported. Surgical ablation remains the basis for management of this tumor, and survival appears to depend on its quality. Prognosis is poor. Our case is original by the tumor's location and mode of discovery.

EFFECT OF RESECTION AND OUTCOME IN PATIENTS WITH RETROPERITONEAL SARCOMA

A consecutive series of 47 patients with retroperitoneal sarcoma (RPS) were resected and prospectively followed. Between July 1994 and March 2005, 47 patients (24 men, 23 women; mean age, 56 years; range, 17-82 years) were evaluated. 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. 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.

Retroperitoneale Sarkome: Diagnostik und Therapie

Due to the fact that there are no distinct anatomical compartments, retroperitoneal sarcomas are moreover diagnosed with evidence of large tumors and infiltration of adjacent organs. In spite of improvement of the diagnostic facilities and surgical techniques, quite frequently local recurrences with unfavourable prognosis turn up even after complete removal. It was the aim of this study to analyze diagnosis, therapy and long-term prognosis in patients with retroperitoneal sarcomas over a period of 10 years. Between January 1995 and January 2005, 379 patients underwent surgery for a primary retroperitoneal tumor at our clinic. Among the 67 (17.1 %) malignant lesions, a sarcoma was found in 35 patients. The present study is focused on the long-term prognosis of those 21 patients with a primary resected retroperitoneal sarcoma, recurrent sarcomas and exploratory laparotomies excluded. The median patient age at the time of surgery was 61 (25-86) years, 57.1 % were males. The duration of symptoms was 3 (1-36) months. A pR0-resection was achieved in 20/21 patients. Among the histopathological tumor types, liposarcomas (n = 10) and leiomyosarcomas (n = 6) were found most frequently. Local recurrence developed in 12 out of 21 patients at 13.5 (5-42) months after the first operation, and in 4 patients distant metastases were observed. The long-term survival of all 21 patients with primary resected retroperitoneal sarcoma was 24 (1-101) months. A more favourable prognosis was seen in patients with leiomyosarcoma as compared with liposarcoma. Retroperitoneal sarcomas are a heterogeneous entity, and they were found among our own patients in 6.1 % of all primary operatively treated retroperitoneal tumors. The strategy of treatment is complex and dependent on the stage, localization and histopathological characteristics. Long-term survival is limited as a result of the high rate of local recurrence.

Intraoperative electron-beam therapy for primary and recurrent retroperitoneal soft-tissue sarcoma

This study assesses the long-term outcome of patients with retroperitoneal soft-tissue sarcomas treated by maximal resection in combination with intraoperative electron-beam therapy (IOERT) and postoperative external-beam radiotherapy. From 1991 to 2004, 67 patients were treated with curative intent for primary (n = 26) or recurrent (n = 41) retroperitoneal soft-tissue sarcoma. All patients underwent maximal resection in combination with IOERT (mean dose, 15 Gy), 45 patients underwent additional postoperative EBRT, and 20 patients were previously irradiated. The 5-year actuarial overall survival (OS), disease-free survival, local control (LC), and freedom from metastatic disease of all patients was 64%, 28%, 40%, and 50%, respectively. The 5-year LC inside the IOERT field was 72%. For patients who completed IOERT and EBRT after R0-resection 5-year and 10-year OS was 80%, and 5-year and 10-year LC was 100%. Only 1 of the 21 patients after R0-resection and only 8 of 34 patients after R1-resection compared with 9 of 12 patients after R2-resection experienced inside IOERT-field relapse. Grade II or higher late complications were seen in 21% of the patients, but only 2 patients required surgical intervention because of late complications. In selected patients, IOERT results in excellent local control and survival, with acceptable morbidity.

Prognostic factors for first recurrence in patients with retroperitoneal sarcoma

Background Retroperitoneal sarcomas are characterized by a high local recurrence rate despite optimal surgical treatment. The definition of prognostic factors for recurrence could help offer high-risk patients a closer follow-up and a multidisciplinary therapeutic approach. Patients and Methods A cohort of 40 patients treated for a primary retroperitoneal sarcoma was retrospectively analyzed. Median follow-up was 24 months. Patient (sex and age), tumor (maximal size, histologic type, tumor localization, and histologic grade), and treatment (complete vs. incomplete surgery) characteristics were included in univariate and multivariate prognostic factor analyses. Results After a median follow-up of 24 months (range 3−121), the overall recurrence rate was 65%. Median time between initial surgery and recurrence was 15 months (range 11.5−29.5). In univariate analysis, surgical positive margins ( P = 0.011), bilateral tumors ( P = 0.0034), nonliposarcoma histologic subtypes ( P = 0.043), and a high histologic grade ( P = 0.0072) were associated with an increased recurrence rate. All these factors except the histologic subtypes retained an independent prognostic value in the multivariate analysis. Death was strongly related to recurrence ( P = 0.0033). Conclusion The optimal treatment of patients with primary retroperitoneal sarcoma should be based on radical surgery, with en bloc organ resection if necessary, to minimize the risk of positive margins. In high-risk patients, close follow-up is mandatory to offer optimal subsequent surgical procedures. The impact of a multidisciplinary therapeutic approach remains to be proved.

At the Crossroads for Retroperitoneal Sarcomas: The Future of Clinical Trials for This “Orphan Disease”

In 1993, the Office of Rare Diseases was established within the National Institutes of Health to ‘‘stimulate and coordinate research on rare diseases.’’ The Office of Rare Diseases defines a rare or orphan disease as ‘‘a condition affecting fewer than 200,000 persons in the United States.’’ Collectively, soft tissue sarcomas (STS) are on the official list. At only 10% to 15% of all STS, retroperitoneal sarcomas (RPS) truly have orphan status. Therefore, how does one acquire evidence-based treatment information on a low-incidence tumor such as RPS? One could simply extrapolate from what is known about the larger group of extremity STS, but this would not be entirely correct. In the era of limbconserving multimodality therapy for extremity STS, local control rates are often upwards of 85%. Unfortunately, overall survival has not improved over the last 20 years. In contrast, local recurrence rates for RPS range from 20% to 50%. 4 In addition, 40% of patients who are disease free at 5 years will develop a recurrence by 10 years. As opposed to extremity STS, most RPS patients succumb to local recurrence in the absence of distant metastases. 4 Therefore, improved local control for RPS might translate into better overall survival. To complicate matters, the challenges of administering radiotherapy for RPS are greater than for extremity STS because of the proximity of vital gastrointestinal or neural structures. By combining two well-designed but somewhat dissimilar trials, Pawlik et al. have made a small step toward improving the treatment of RPS. They showed that 89% of patients were able to complete preoperative radiation. For the 57 patients who underwent potentially curative surgery, the R0/R1 resection rate was 95%, the 5-year local recurrence free survival rate was 60%, and only 20% of patients experienced some component of distant failure. Ten patients developed distant metastases during preoperative radiation and were spared the otherwise noncurative operation they would have received had they undergone surgical resection immediately after diagnosis. However, preoperative therapy may be a doubleedged sword. Three patients initially believed to have resectable tumor could not undergo complete gross resection at the time of surgical exploration. Things might have been different had surgery not been delayed for several weeks as a result of radiation. The findings of this study are provocative but reinforce the need for a well-designed randomized, prospective trial to identify the role of preoperative radiation for primary RPS. Confounding variables included the following: 25% of their RPS were recurrent, 28% patients received <45 Gy of radiation (less likely to have a significant biologic effect on the tumor), an intraoperative or postoperative radiation boost was used in 60% of the surgical patients, and some patients received systemic chemotherapy. Of Received October 13, 2005; accepted October 26, 2005; published online February 28, 2006. Address correspondence and reprint requests to: John M. Kane III, MD, Surgical Oncology, Roswell Park Cancer Institute, Elm and Carlton Streets, Buffalo, NY 14263; E-mail: john.kane@ roswellpark.org.

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

To analyze treatment and survival in 34 patients (28 resected) with primary or recurrent retroperitoneal sarcoma (RPS). 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. 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). An aggressive surgical approach in both primary and recurrent RPS is associated with long-term survival.

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

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. Medical therapies have shown little efficacy in the management of retroperitoneal sarcomas, making total surgical extirpation the best chance for patient cure. The case histories of all patients operated upon for retroperitoneal sarcomas between January 1983 and December 1995 were retrospectively reviewed. 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. 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.

Surgical management of retroperitoneal sarcomas associated with external and intraoperative electron beam radiotherapy

Aims: To report outcomes of adults with retroperitoneal sarcoma (RS) treated by surgery, external beam radiotherapy (EBRT) and intraoperative electron beam radiotherapy (IORT). Methods: From July 1988 to February 2001; 24 patients with primary and recurrent RS were diagnosed and treated. The median dose and energy of IORT delivered was 15 Gy/9 meV. EBRT dose varies between 45–50 Gy. Results: There were five primary and 19 recurrent tumours. One primary and five recurrent tumours underwent R0 resection. There were 12 liposarcomas and 19 grade I tumours; 13 patients developed local recurrence and three developed distant metastases. Twenty-two patients received IORT associated with EBRT: 11 developed recurrences. Six patients developed Neurotoxicity (4 grade II and 2 grade III). Disease free survival and overall survival at 5 years was 28 and 56% respectively. Conclusions: EBRT with IORT treatment is a promising technique for local control. Lower recurrence rates are associated with radical (R0) surgical procedures.

698 Evaluation of a clinically applicable post-surgical classification system for primary retroperitoneal soft tissue sarcoma

Heuristics and metaheuristics are inevitable ingredients of most of the general purpose ILP solvers today, because of their contribution to the significant boost of the performance of exact methods. In the field of bi/multi-objective optimization, to the best of our knowledge, it is still not very common to integrate ILP heuristics into exact solution frameworks. This paper aims to bring a stronger attention of both the exact and metaheuristic communities to still unexplored possibilities for performance improvements of exact and heuristic multi-objective optimization algorithms.We focus on bi-objective optimization problems whose feasible solutions can be described as 0/1 integer linear programs and propose two ILP heuristics, boundary induced neighborhood search (BINS) and directional local branching. Their main idea is to combine the features and explore the neighborhoods of solutions that are relatively close in the objective space. A two-phase ILP-based heuristic framework relying on BINS and directional local branching is introduced. Moreover, a new exact method called adaptive search in objective space (ASOS) is also proposed. ASOS combines features of the ϵ-constraint method with the binary search in the objective space and uses heuristic solutions produced by BINS for guidance. Our new methods are computationally evaluated on two problems of particular relevance for the design of FTTx-networks. Comparison with other known exact methods (relying on the exploration of the objective space) is conducted on a set of realistic benchmark instances representing telecommunication access networks from Germany.

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.

984 Poster Surgical resection and radiotherapy for primary retroperitoneal soft tissue sarcoma

984 Poster Surgical resection and radiotherapy for primary retroperitoneal soft tissue sarcoma

Use of intraoperative electron beam radiotherapy in the management of retroperitoneal soft tissue sarcomas

Purpose : To evaluate the disease control, survival results, and tolerance of intraoperative electron beam radiotherapy (IOERT) as a component of treatment for retroperitoneal soft tissue sarcomas. Methods and Materials : Between March 1981 and September 1995, 87 patients with primary ( n = 43) or recurrent ( n = 44) retroperitoneal or intrapelvic sarcomas received IOERT as a component of treatment at the Mayo Clinic. The tumors were high grade in 54 patients (62%) and low grade in 33 (38%). The median tumor size was 10 cm (range 2–36). All patients underwent maximal surgical resection with IOERT; in 72 patients, only microscopic or no residual tumor remained. The IOERT doses ranged from 8.75 to 30 Gy (median 15). All primary tumors received external beam irradiation (EBRT) with a median dose of 48.6 Gy. Thirty-four of the 44 recurrent tumors received EBRT to a median dose of 45 Gy. All patients were followed prospectively for outcome and toxicity evaluation. Results : The median follow-up, based on 46 patients (53%) currently alive, was 3.5 years. The overall estimated 5-year survival was 47%. For patients with tumors ≥10 cm, the 5-year overall survival was significantly poorer (28%) than for those with smaller lesions (60%) ( p = 0.01). Neither primary vs. recurrent status nor tumor grade had a significant impact on survival. Patients with gross residual tumor had a marginally significantly poorer survival compared with patients with microscopic or no residual tumor, with a 5-year survival rate of 37% and 52%, respectively ( p = 0.08). A total of 49 patients (56%) experienced failure, including 20 local recurrences (23%). The median time to failure was 2.3 years. Four recurrences were within the IOERT field, 3 within the IOERT and EBRT field, and 13 within the EBRT field alone. The 3- and 5-year estimated local control rate was 77% and 59%, respectively. Local control was marginally significantly affected by the amount of residual tumor, with a 5-year local control rate of 41% for those with gross residual tumor, 60% for those with microscopic residual tumor, and 100% for those with no residual tumor ( p = 0.09). Gastrointestinal complications were recorded in 12 incidences (Grade 3 or higher toxicity). These complications were believed to be secondary to surgery and/or EBRT in 10 of the 12 cases. Seven patients had fistula formation, and 3 experienced severe proctitis. Grade 3 peripheral neurologic toxicities occurred in 9 patients (10%), but none had pain as a component of their neuropathy. Conclusion : Retroperitoneal soft tissue sarcomas can be treated with an aggressive combined approach of EBRT, surgery, and IOERT, with acceptable toxicity. Local control in primary disease appears to be improved in this retrospective series with this approach. Distant disease control and options for recurrent disease needs further definition.

Intraoperative radiation therapy.

The modern use of intraoperative radiation therapy (IORT) was initiated by the studies of Abe and colleagues at the University of Kyoto. This work stimulated significant laboratory and clinical investigation into the use of IORT throughout Japan, Europe, and the United States. Because of this experience, single high doses of irradiation can be safely delivered to a tumor volume in appropriate clinical situations. Most importantly, this high dose of additional radiation treatment yields improved local control of selected tumors. Treatment programs of external beam radiation therapy, surgical resection, and IORT for patients with locally advanced primary and recurrent rectal carcinoma and retroperitoneal sarcoma have yielded excellent local control and higher survival rates. The future of IORT will be in the successful integration of this therapy into multimodality treatment programs of chemotherapy, external beam irradiation, and surgery for locally advanced malignancies.

Long-term results of intraoperative electron beam radiotherapy for primary and recurrent retroperitoneal soft tissue sarcoma

Purpose: This study assesses the long-term outcome of patients with retroperitoneal sarcoma treated by preoperative external beam radiotherapy, resection, and intraoperative electron beam radiation (IOERT). Methods and Materials: From 1980 to 1996, 37 patients were treated with curative intent for primary or recurrent retroperitoneal soft tissue sarcoma. All patients underwent external beam radiotherapy with a median dose of 45 Gy. This was followed by laparotomy, resection, and IOERT, if feasible. Twenty patients received 10–20 Gy of IOERT with 9–15 MeV electrons. These patients were compared to a group of 17 patients receiving preoperative irradiation without IOERT. Results: The 5-yr actuarial overall survival (OS), disease-free survival, local control (LC), and freedom from distant disease of all 37 patients was 50%, 38%, 59%, and 54%, respectively. After preoperative irradiation, 29 patients (78%) underwent gross total resection. For 16 patients undergoing gross total resection and IOERT, OS and LC were 74% and 83%, respectively. In contrast, these results were less satisfactory for 13 patients undergoing gross total resection without IOERT. For these patients, OS and LC were 30% and 61%, respectively. Four patients experienced treatment-related morbidity. Conclusions: In selected patients, IOERT results in excellent local control and disease-free survival with acceptable morbidity.