Local recurrence of soft tissue sarcoma following brachytherapy

Brachytherapy for Organ and Function Preservation in Soft-Tissue Sarcomas in Adult and Paediatric Patients

Adjuvant radiotherapy is an integral component in the management of soft-tissue sarcomas. Brachytherapy is a very convenient and conformal way of delivering adjuvant radiotherapy in such tumours, which spares the surrounding normal tissue. Randomised studies have established the efficacy of brachytherapy in the adjuvant setting, with a 5-year local control of 80-85%. High dose rate, low dose rate and pulsed dose rate have shown equivalent local control, but high dose rate has gained popularity owing to patient convenience, radiation safety and flexibility in dose optimisation. Freehand insertion perioperative brachytherapy (intraoperative placement and postoperative treatment) is the most commonly used technique in soft-tissue sarcomas, with intraoperative radiotherapy and radioactive seed placement being the less commonly used techniques. Brachytherapy can be used as monotherapy or in combination with external beam radiotherapy, such as in cases of close/positive margins for safe dose escalation. Although the quantum of side-effects with external beam radiotherapy has considerably reduced with the evolution of technology and the introduction of intensity modulation (intensity-modulated radiotherapy), brachytherapy still scores better in terms of dose conformality, especially in recurrent tumours (previously irradiated) and when used to treat paediatric and geriatric patients.

Permanent interstitial 125I seed implantation as a salvage therapy for pediatric recurrent or metastatic soft tissue sarcoma after multidisciplinary treatment

BACKGROUND

The management of pediatric recurrent or metastatic soft tissue sarcoma after multimodal treatment remains challenging. We investigated the feasibility, efficacy, and morbidity of permanent interstitial (125)I seed implantation under image guidance as a salvage treatment for pediatric patients with recurrent or metastatic soft tissue sarcoma.

METHODS

This was a retrospective study of 10 patients who underwent percutaneous ultrasound or computed tomography (CT) guided permanent (125)I seed implantation. Postoperative dosimetry was performed for all patients. Actuarial D90 was 121-187.1 Gy (median, 170.3 Gy). The number of (125)I seeds implanted was 6-158 (median, 34.5), with a median specific activity of 0.7 mCi per seed (range, 0.62-0.8 mCi); total activity was 4.2-113.76 mCi. Follow-up time was 6-107 months (median, 27.5 months); no patients were lost to follow-up.

RESULTS

The overall response rate (complete response + partial response) was 8/10 (80 %), including two patients with complete response (CR) (20 %) and five patients with partial response (PR) (60 %). Local control rates after 1 and 2 years were 70.1 and 62.3 %, respectively, with a mean local control time of 70.6 months (95 % confidence interval (CI) 45.1-96.0). Survival rates after 1 and 2 years were 68.6 and 57.1 %, respectively, with a mean survival time of 65.3 months (95 % CI 34.1-96.5). Three patients died from distant metastasis; one died from local recurrence 12 months after seed implantation. Three patients suffered a grade I skin reaction and one developed ulceration. No severe adverse neurologic sequelae or blood vessel damage occurred.

CONCLUSIONS

Image guided permanent interstitial (125)I seed implantation as a salvage treatment appears to have a satisfactory outcome in children with recurrent or metastatic soft tissue sarcoma.

Adjuvant Radiation Therapy of Retroperitoneal Sarcoma: The Role of Intraoperative Radiotherapy (IORT)

Purpose. The purpose is to review the natural history, the clinicopathological prognostic factors, and the role of adjuvant radiation therapy with particular attention to the limited but favorable experience with IORT.Methods. Retroperitoneal sarcomas present a continuing therapeutic challenge to the oncologist. In contrast to sarcomas of the extremity and superficial trunk in which complete resection plus radiation therapy results in excellent local control, sarcomas of the retroperitoneum are difficult to resect and even if completely resected, demonstrate high rates of local relapse, the primary pattern of failure. Due to the proximity of normal organs, the delivery of therapeutic doses of adjuvant external beam radiation therapy is problematic.To deliver adequate doses (>60 Gy) of external beam to most patients would result in unacceptable toxicity. The therapeutic dilemma is unfortunate and better strategies are needed. One attractive approach has been to incorporate intraoperative radiation therapy (IORT) with maximal resection and external beam radiation. Results and Discussion. A number of institutions have explored this approach with encouraging preliminary results.

Perioperative high-dose-rate brachytherapy in soft tissue sarcomas of the extremity and superficial trunk in adults: initial results of a pilot study

PURPOSE

This study was undertaken to determine the feasibility of perioperative high-dose-rate brachytherapy (PHDRB) as an alternative to standard low-dose-rate brachytherapy in adult patients with soft tissue sarcomas.

METHODS AND MATERIALS

Twenty-five adult patients with soft tissue sarcomas of the extremities or the superficial trunk were treated with surgical resection and PHDRB (16, 24, or 32Gy) for negative, close/microscopically positive, or grossly involved surgical resection margins, respectively. External beam radiation therapy (45Gy) was added postoperatively. Adjuvant chemotherapy with ifosfamide and doxorubicin was given to patients with high-grade tumors.

RESULTS

Resection margins were negative in 6 patients (24.0%), close/microscopically positive in 18 (72.0%), and grossly involved in 1 (4.0%). One patient (4.0%) with wound dehiscence needed reoperation. Three patients failed in the anatomical region treated, but relapse sites were not adjacent to the area treated with PHDRB. After a median followup of 23.2 months (range 2.8-48.0), the 4-year local and regional control rates were 100% and 80.5%, respectively. Four-year overall survival was 78.2%.

CONCLUSIONS

Locoregional control and survival results are encouraging for this high-risk patient population. PHDRB results seem to be similar to those obtained with low-dose-rate brachytherapy.

Current results of brachytherapy for soft tissue sarcoma

Perioperative brachytherapy results in a better local control rate than surgery alone for extremity soft tissue sarcoma. Brachytherapy enables the delivery of a high radiation dose to a limited volume of tissue, allows the reduction of radiation treatment time, enables direct visualization of the tumor bed and surrounding critical structures, and costs less than external beam radiotherapy. The literature seems to regard the effectiveness of brachytherapy as comparable to that of external beam radiotherapy, and the side effect profile is acceptable. Traditional low-dose-rate brachytherapy methods require extended periods of patient isolation, but recent technologic advances may obviate this necessity. Newer high-dose-rate (HDR) brachytherapy delivery methods allow for the fractionation of radiation delivery and outpatient treatment in some cases. Furthermore, with HDR brachytherapy, the radiation dose distribution can be tailored around critical anatomic structures. Although the application of HDR brachytherapy to soft tissue sarcoma is relatively new, it seems to result in a satisfactory local control rate and may replace traditional low-dose-rate techniques.

Brachytherapy for locally recurrent soft-tissue sarcoma

Radiation is used to reduce potential risk of local recurrence from microscopic residual disease after surgical resection. Brachytherapy is a clinically established means of providing radiation for soft-tissue sarcomas that recur after surgical resection alone or surgical resection and radiation. Although the total dose of radiation that is prescribed is approximately the same for patients undergoing external beam radiation or brachytherapy, the radiobiologic characteristics of brachytherapy, based on the inverse-square law, provide higher doses of radiation to the surgical bed. This provides a theoretical advantage for the use of brachytherapy as compared with external beam radiation among patients with recurrence after surgical resection. When soft-tissue sarcomas recur in a previously irradiated area, further external beam radiation generally is not possible; therefore, brachytherapy allows a radiotherapeutic alternative in an attempt to reduce the risk of further local recurrence. Recommendations for patient selection, the total dose of radiation, and the radiation dose-rate are outlined. Standard grading systems for response, symptoms, and severity of complications should be used.

The American Brachytherapy Society recommendations for brachytherapy of soft tissue sarcomas

PURPOSE

This report presents the American Brachytherapy Society (ABS) guidelines for the use of brachytherapy for patients with soft tissue sarcoma.

METHODS AND MATERIALS

Members of the ABS with expertise in soft tissue sarcoma formulated brachytherapy guidelines based upon their clinical experience and a review of the literature. The Board of Directors of the ABS approved the final report.

RESULTS

Brachytherapy used alone or in combination with external beam irradiation is an established means of safely providing adjuvant local treatment after resection for soft tissue sarcomas in adults and in children. Brachytherapy options include low dose rate techniques with iridium 192 or iodine 125, fractionated high dose rate brachytherapy, or intraoperative high dose rate therapy. Recommendations are made for patient selection, techniques, dose rates, and dosages. Complications and possible interventions to minimize their occurrence and severity are reviewed.

CONCLUSION

Brachytherapy represents an effective means of enhancing the therapeutic ratio, offering both biologic and dosimetric advantage in the treatment of patients with soft tissue sarcoma. The treatment approach used depends upon the institution, physician expertise, and the clinical situation. Guidelines are established for the use of brachytherapy in the treatment of soft tissue sarcomas in adults and in children. Practitioners and cooperative groups are encouraged to use these guidelines to formulate their treatment and dose-reporting policies. These guidelines will be modified, as further clinical results become available.

Adjuvant brachytherapy in the treatment of soft-tissue sarcomas

For many patients with STS, administering adjuvant radiation treatments in the form of interstitial brachytherapy provides an excellent alternative to a protracted course of EBRT. Ideal patients are those with intermediate- or high-grade tumors amenable to en bloc resection. Attractive features of this approach include an untainted pathologic specimen, expeditious completion of treatment, reduction in wound complications, and improved functional outcome. Brachytherapy can permit definitive reirradiation by tightly localizing the high dose radiation exposure. It is also useful in patients who are known to have or be at high risk of metastatic disease, for whom the rapid completion of local treatment allows systemic therapy to begin quickly. Introduction of HDR techniques has shifted the delivery of brachytherapy from inpatient solitary confinement to an outpatient setting. Early reports using HDR brachytherapy for treatment of adult and pediatric STS are quite encouraging. The clinical equivalence between hyperfractionated HDR schedules and traditional LDR techniques is gaining acceptance.

The effect of combined external beam radiotherapy and brachytherapy on local control and wound complications in patients with high-grade soft tissue sarcomas of the extremity with positive microscopic margin

PURPOSE

A previously reported randomized trial from out institution demonstrated a local control advantage to adjuvant brachytherapy (BRT) for completely resected high grade soft tissue sarcoma (STS). In recent years, BRT boost has been combined with wide field external beam radiotherapy (EBRT) for selected patients in whom the margin(s) of resection was positive. This study evaluates the impact of BRT boost plus EBRT on local control in this subset of patients and on wound complication rates.

METHODS AND MATERIALS

Between January, 1987 and December, 1992, 105 adult patients with primary or locally recurrent high grade STS of the extremity were treated with wide local excision and BRT alone (87 patients; dose: 45 Gy) or BRT plus EBRT (18 patients; dose: 15-20 Gy BRT + 45-50 Gy EBRT). The margin(s) of resection was positive in 10 out of 18 patients in the BRT + EBRT group vs. 17 out of 87 patients in the BRT alone group. Wound complications were classified as major if they required further operative intervention; moderate if there was purulent discharge, hematoma > 25 ml, wound separation > 2 cm, and persistent seroma requiring drainage; or minor if less than moderate. Median follow-up was 22 months.

RESULTS

The overall 2-year actuarial local control rate was 86%. There was no difference in the 2-year actuarial local control rate between the BRT + EBRT group (90%) and the BRT alone group (82%) (9 = 0.32). However, for patients with positive resection margins the use of BRT + EBRT produced better local control than BRT alone [9 out of 10 (90%) vs. 10 out of 17 (59%)]. This difference approached but did not reach statistical significance (p = 0.08). No difference was seen in patients with negative margins. There was no significant difference in the overall wound complication rate (26% BRT vs. 38% BRT + EBRT, p = 0.31) nor in the combined major and moderate wound complication rate (16% BRT vs. 27% BRT + EBRT, p = 0.39).

CONCLUSION

Our preliminary data suggest a trend in favor of BRT boost + EBRT as the optimal adjuvant local strategy for STS with positive resection margins. There is no significant difference in the wound complication rate with either technique.

Malignant fibrous histiocytoma: outcome and prognostic factors following conservation surgery and radiotherapy

PURPOSE

Malignant fibrous histiocytoma is the most common type of soft tissue sarcoma. This communication presents an analysis of outcome and prognostic factors based on a retrospective review of patients with this disease treated by conservation surgery and radiotherapy.

METHODS AND MATERIALS

From 1966 to 1991, 271 consecutive patients with malignant fibrous histiocytoma were treated with conservation surgery and radiotherapy. The outcome with local control, metastatic relapse, and survival as end points was evaluated by univariate and multivariate statistics to delineate independently significant prognostic factors.

RESULTS

Postoperative radiation at a mean dose of 62.8 Gy was used in 195 patients and preoperative radiation at a mean dose of 50 Gy was used in 76 patients. At a median follow-up of 7.3 years, 123 patients (45%) developed disease relapse at some site. Fifty-seven (21%) developed local recurrence leading to an actuarial local relapse rate of 26% at 10 years, 83 (31%) developed metastatic relapse for a 10-year actuarial metastatic rate of 33%, and the 5-, 10-, and 15-year survival rates were 68, 60, and 46%, respectively. For local control, prior local recurrence (in 53 patients) was identified as an adverse factor, yielding a 10-year recurrence rate of 42% compared to 22% for 218 patients without prior disease (p < 0.01). Also, a positive surgical margin (in 46 patients) was adverse with a 10-year local recurrence rate of 39% compared to a recurrence rate of 17% with negative margins (167) (p=0.01). Patients with pathologically undocumented resection margins (58) had a local recurrence rate similar to those with positive margins (41% at 10 years). Tumor site (extremity vs. nonextremity), location (proximal vs. distal), size (< or = 5 cm vs. > 5 cm), and histology (myxoid vs. nonmyxoid) were not significant determinants of local outcome. For metastatic relapse, the major determinants of outcome were histology (myxoid vs. nonmyxoid) and tumor size. Myxoid tumors (59 patients) had a low metastatic propensity (13% 10-year metastatic rate) compared to nonmyxoid tumors (212 patients) (40% 10-year metastatic rate) (p < 0.01). Size was an important covariate for metastases for both myxoid and nonmyxoid tumors. For nonmyxoid tumors the 10-year metastatic rates were 23 and 51% for lesions less than or greater than 5 cm. For myxoid tumors a significant metastatic rate appeared only for tumors exceeding 10 cm (10-year metastatic rates of 8% vs. 44% for tumors less than vs. greater than 10 cm). In this retrospective review we found no evidence that adjuvant chemotherapy decreased the metastatic rate. In multivariate analysis for metastatic relapse and survival, tumor histology (nonmyxoid vs. myxoid) and size (< 5 cm vs. > 5 cm) were the only independent determinants of outcome.

CONCLUSION

Malignant fibrous histiocytoma is a heterogeneous disease and its myxoid variant must be recognized as a distinct entity. Both variants are locally aggressive and require equally aggressive local therapy. Conservation surgery striving for negative margins with radiation therapy provides acceptable local control and is the treatment of choice for this disease. Patients with myxoid tumors do not require systemic therapy; patients with nonmyxoid disease exceeding 5 cm are at significant risk for metastases and the development of effective adjuvant treatment is an important research tool.

Wound complications after resection and immediate postoperative brachytherapy in the management of soft-tissue sarcomas

BACKGROUND

When used as the sole source of postoperative radiotherapy, brachyradiation therapy (BRT) (4,500-6,000 cGy) should be delayed beyond the fourth postoperative day to minimize wound complications. However, when 1,000-2,000 cGy BRT are given as a "boost" to the tumor bed, it is unclear if a similar treatment delay is necessary. The purpose of this review was to determine the incidence of wound complications when BRT (1,000-2,000 cGy) is administered < or = 48 h after soft-tissue resection.

METHODS

The results of treatment in 21 patients with soft-tissue sarcomas of the extremity and superficial trunk treated with resection, immediate postoperative brachytherapy, and external beam radiation were reviewed. All patients were followed through the completion of radiation (median follow-up 30 months). A median of seven (range 3-24) after-loading catheters were placed at the time of resection and were loaded with iridium-192 a median of 2 days postoperative to deliver 1,000-2,000 cGy radiation.

RESULTS

Eight patients (38%) experienced minor wound complications (seromas, wound separation, and flap edge necrosis) within 30 days of operation. There were no early complications that required reoperation or delayed further therapy.

CONCLUSIONS

Brachytherapy (1,000-2,000 cGy) can be administered < or = 48 h postoperatively with a low risk of major wound complications. Minor wound complications are common but do not delay further treatment.

Soft tissue sarcomas

This synthesis of the literature on radiotherapy for sarcomas originating in the body's soft, supportive tissues, ie, muscle, connective tissue, and fatty tissue is based on 71 scientific articles, including 4 randomized studies, 5 prospective studies, and 26 retrospective studies. These studies involve 3,444 patients. Over 90% of patients with soft tissue sarcomas in the arms and legs can be treated in a way that preserves the extremities. Subcutaneous and intramuscular sarcomas can be treated surgically with little functional loss or risk for local recurrence without adjuvant radiotherapy. To avoid amputation, surgery is often combined with radiotherapy for treatment of local relapse. Adequate surgical margins are usually difficult to achieve for head/neck tumors and retroperitoneal tumors, and therefore surgery is often combined with radiotherapy to reduce the risk for local relapse. Pre- and postoperative radiotherapy are similar. A disadvantage of preoperative radiotherapy is that it reduces the opportunity for exact diagnosis and determining morphobiologic sarcoma parameters. To further improve treatment results for advanced sarcomas, it is necessary to introduce other fractionation schedules, mainly hyperfractionation. This places greater demands on radiotherapy, mainly for staff resources. Combining radiotherapy and local intraarterial chemotherapy involves greater risks for complications and has not shown better treatment results than pre- or postoperative radiotherapy alone, and it is not recommended as standard treatment for soft tissue sarcomas. Intraoperative treatment methods should be targeted for further study and development.

Conservative surgery and adjuvant radiation therapy in the management of adult soft tissue sarcoma of the extremities: clinical and radiobiological results

PURPOSE

The outcome of adult patients with soft tissue sarcoma of the extremities treated with conservative surgery and adjuvant irradiation was evaluated to (a) determine the appropriate treatment volume and radiation dosage in the postoperative setting, and (b) correlate in vitro radiobiological parameters obtained prior to therapy with clinical outcome.

METHODS AND MATERIALS

Sixty-four consecutive adult patients with soft tissue sarcoma of the extremities (40 lower, 24 upper) who underwent conservative surgery and adjuvant irradiation 7 preoperative, 50 postoperative, 7 perioperative) between 1978 and 1991 were reviewed. The initial radiation field margin surrounding the tumor bed/scar was retrospectively analyzed in all postoperative patients. Initial field margins were < 5 cm in 12 patients, 5-9.9 cm in 32 and > or = 10 cm in 6. Patients with negative pathological margins were initially treated with traditional postoperative doses (64-66 Gy); however, in later years the postoperative dose was reduced to 60 Gy. Thirteen cell lines were established prior to definite therapy, and radiobiological parameters (multitarget and linear-quadratic) were obtained and correlated with outcome.

RESULTS

Postoperative patients treated with an initial field margin of < 5 cm had a 5-year local control of 30.4% vs. 93.2% in patients treated with an initial margin of > or = 5 cm (p = 0.0003). Five-year local control rates were similar in patients treated with initial field margins of 5-9.9 cm (91.6%) compared with those treated with > or = 10 cm margins (100%) (p = 0.49). While postoperative patients receiving < 60 Gy had a worse local control than those receiving > or = 60 Gy (p = 0.08), no difference was seen in local control between patients receiving less than traditional postoperative doses (60-63.9 Gy) (74.4% vs. those receiving 64-66 Gy (87.0%) (p = 0.5). The local control of patients treated in the later years of the study, with strict attention to surgical and radiotherapeutic technique, was 87.6%. Severe late sequelae were more frequent in patients treated with doses > or = 63 Gy compared to patients treated with lower doses (23.1% vs. 0%) (p < 0.05). Mean values for Do, alpha, beta, D, n and SF2 obtained from the 13 cell lines were 115.7, 0.66, 0.029, 2.15, 0.262, respectively. Four of the 13 cell lines established prior to therapy ultimately failed locally. The radiobiological parameters of these cell lines were similar to the other nine cell lines in terms of radiosensitivity.

CONCLUSIONS

Our data confirm the importance of maintaining an initial field margin of at least 5 cm around the tumor bed/scar in the postoperative setting. No benefit was seen with the use of margins > or = 10 cm. In addition, patients undergoing wide local excision with negative margins can be treated with lower than traditional postoperative doses (60 Gy) without compromising local control and with fewer chronic sequelae. Finally, it does not appear that inherent tumor cell sensitivity is a major determinant of local failure following radiation therapy and conservative surgery in soft tissue sarcoma.

Combined surgery and radiation therapy for limb preservation in soft tissue sarcoma of the extremity: the Massachusetts General Hospital experience

The results presented here indicate that excellent local control rates can be achieved using radiation in combination with limb-sparing surgery. At least three challenges remain and need to be addressed in future prospective trials. One is the need to reduce wound complications. In this regard, the influence of chemotherapy on the healing of the irradiated wound needs to be better defined as well as the role of recombinant growth factors and cytokines in tissue repair. Second is the need to better assess functional and psychological outcome in patients who are long-term survivors as well as in patients who succumb to distant disease. Despite the limited information on this end-point, it appears that strategies that reduce wound morbidity ultimately have a beneficial outcome with regard to functional and psychological status. Third, our greatest challenge is to improve the rates of distant disease control. Despite excellent local control rates following limb-sparing procedures, greater than 50% of patients will ultimately die of their disease. New systemic therapies must be developed to control systemic dissemination. The ultimate goal of combined surgery, radiation, and chemotherapy will be to preserve limb function in patients who are cured of their disease.

Intraoperative interstitial iridium brachytherapy in the management of soft tissue sarcomas: preliminary results of a feasibility phase II study

Between May 1986 and June 1992, 48 patients with soft tissue sarcomas underwent 50 intraoperative interstitial implants in conjunction with conservative tumoral resections. Brachytherapy was part of the initial treatment in 27 cases and was done in 21 other previously treated patients. For the last ones brachytherapy was, in most of the cases, the only treatment in addition to surgery. The implant dose was 40-65 Gy. When combined with external irradiation the mean prescribed dose was 20 Gy (12-25 Gy). With a median follow-up of 33 months, the 3-year actuarial survival rate was 81% and the local disease-free survival 91.7%. Five local failures were observed only in patients with recurrent sarcomas: two were inside the treated volume and three outside (local failure 5/48 = 10.4%). Acute side-effects occurred in 11 patients (11/48 = 23%), with skin breakdown (two cases) infection and hematoma (one case), infection, lymphocele, secondary skin breakdown and vascular rupture (one case), infection and limited skin breakdown (two cases) and delayed healing (five cases). As a consequence, six patients required reoperation but no amputation was necessary. The functional results were good. Only three patients had a moderate limitation of movement. Late complications occurred in five patients: bone fracture (one case), leg oedemas not interfering with normal activity (three cases), peripheral neuropathy fibrosis related requiring surgery (one case). Therefore, this preliminary report shows that adjuvant intraoperative brachytherapy is feasible and is safe in treating soft tissue sarcomas, even in previously irradiated patients. However, further evaluation is needed to determine the real place of intraoperative implant in the management of soft tissue sarcomas.

Soft tissue sarcomas: experience with intraoperative brachytherapy in the conservative management

Forty-eight patients with soft tissue sarcomas were treated with Iridium implant after wide local excision between 1980 and 1990 at our institution. External irradiation was also given postoperatively in 33 patients with initially resectable tumours (treatment A) and preoperatively in 3 with initially unresectable tumours (treatment C); brachytherapy was the only treatment in 12 patients presenting small superficial tumours or recurring after previous irradiation (treatment B). Median follow up was 51 months (range 6-148). Fifteen patients (31%) failed; local recurrence was present in 9 (18.8%) and distant metastases in 11 (22.9%). Local failures were 3/33 (9%) after the treatment A, 4/12 after the treatment B, 3/2 after the treatment C. The incidence of local failures was affected by the tumor size, the presence of positive histology at the resection margins, and the total radiation dose. There was no impairment of wound healing and no necrosis; a severe sclerosis was observed only in the 3 patients receiving preoperative irradiation probably because large size fractions were used. We concluded that brachytherapy should be included in the radiation program for soft tissue sarcomas when a satisfactory geometry may be achieved and in particular when the tumor is located in sites where external irradiation only has a higher probability of producing major side effects.