Iodine-125 brachytherapy for a desmoid tumor in the abdomen-thorax: A retrospective study

PURPOSE

To investigate the safety and efficacy of iodine-125 seed implantation in the treatment of abdomen-thorax desmoid tumors (DTs).

METHODS AND MATERIALS

Data from 14 DT patients who received brachytherapy with iodine-125 seeds were retrospectively collected from 2014 to 2020. The operation was completed using CT guidance and the treatment plan system (TPS). The number of lesions and the target dosimetry parameters were recorded. After brachytherapy, the lesions were evaluated using response evaluation criteria in solid tumors (RECIST).

RESULTS

Fourteen patients with 18 lesions were enrolled in this study; eleven lesions were in the thorax, seven were in the abdomen, and the lesion gross tumor volume (GTV) was 82.10 cc (interquartile range [IQR]: 40.37, 203.42 cc). The median number of seeds was 88 (IQR: 35, 158), and the median prescription dose was 120 Gy (IQR: 115, 120 Gy). The D90 was 123 ± 16.7 Gy, the V90 was 97% (IQR: 95.00, 97.25%), and the V200 was 27% (IQR: 14.50, 33.00%). The median follow-up time for each lesion was 34 (IQR: 23, 67) months, and the local response rate was 100%. Following brachytherapy, the overall survival was 52.3 ± 30.72 months. One year after brachytherapy, one patient experienced persistent worsening of a brachial plexus injury; another received a ureteral stent. No brachytherapy-related complications were observed in the remaining patients.

CONCLUSIONS

Iodine-125 brachytherapy is a novel treatment option for DT of the abdomen and thorax. Although it is a safe and effective treatment, the radiation dose of iodine-125 brachytherapy for DT-embedded organs at risk must be investigated further.

Radiation-induced Desmoid Tumor Development in the Radiotherapy Field in a Child With Pineoblastoma: A Case Report

Although treatment-related secondary malignancies are rare, they are important problems after the treatment of childhood malignant diseases. Irradiation-induced sarcomas are the development of sarcoma different from the primary tumor after a latent period of ≥3 years or more in the radiotherapy field. Desmoid tumor is extremely rare as irradiation-induced tumor. A 7.5-year-old girl was referred to our hospital after a subtotal mass excision for a solid lesion with a cystic component located in the pineal gland. Pathologic examination revealed pineoblastoma. After surgery, craniospinal radiotherapy, and chemotherapy consisting of vincristine, cisplatin, and etoposide were performed. Painless swelling in the left parieto-occipital region ~75 months after the end of the treatment developed in the patient. A mass was detected in the intracranial but extra-axial region by radiologic imaging methods. Due to the total removal of the mass and the absence of a tumor in the surgical margins, she was followed up without additional treatment. The pathologic diagnosis was a desmoid tumor. She was followed up disease free for ~7 years after the primary tumor and ~7 months after the secondary tumor. Treatment-related desmoid tumor development after treatment for a central nervous system tumor in a child is extremely rare.

Optimal radiotherapy strategy for primary or recurrent fibromatosis and long-term results

Purpose

Although locally invasive or recurrent fibromatosis is primarily treated with surgery, radiotherapy (RT) produces local control for recurrent/unresectable tumors or those with positive surgical margins. Herein, we describe our updated institutional experience with RT to treat fibromatosis.

Methods

Forty-seven patients with fibromatosis received RT between 1990 and 2015, and were followed for ≥12 months. Eight patients received RT for gross tumors, and 39 received postoperative RT after single/multiple prior surgeries. A median dose of 54 Gy was prescribed for definitive RT; 48.6, 50.4, and 54 Gy were prescribed for R0, R1, and R2 resected tumors, respectively. Recurrences were classified as in-field, marginal, or out-field. Prognostic factors were also evaluated.

Results

Seven recurrences were noted, including 2 in-field, 4 marginal, and 1 out-field, after a median follow-up of 60 months. In-field recurrences occurred in 1 patient who received 40.5 Gy of salvage RT after postoperative recurrence and another who received 45 Gy for R1 resection after multiple prior operations. All marginal failures were due to insufficient clinical target volume (CTV) margins regardless of dose (3 with 45 Gy and 1 with 54 Gy). On multivariate analysis, a CTV margin ≥5 cm and dose >45 Gy were significant predictors of non-recurrence (p = 0.039 and 0.049, respectively). Subgroup analysis showed that patients with both an CTV margin ≥5 cm and a dose >45 Gy showed a favorable outcome.

Conclusions

RT is a valuable option for treating aggressive fibromatosis; doses ≥45 Gy and a large field produce optimal results. For in-field control, a higher dose is more necessary for gross residual tumors than for totally excised lesions.

Radiation Therapy as an Alternative Treatment for Desmoid Fibromatosis

AIM

To determine the outcome after radiation therapy for desmoid fibromatosis.

MATERIALS AND METHODS

A retrospective review of 50 patients treated between 1988 and 2016 in a specialised bone and soft tissue tumour clinic.

RESULTS

The median age at the time of radiation therapy was 36.8 years (range 15.1-69.0) and the median follow-up time was 51 months. Forty-three patients underwent radiation therapy as the definitive treatment with a median dose of 56 Gy (range 30-58.8 Gy). The median dose for the seven patients treated with postoperative radiation therapy was 50.4 Gy (range 48-56 Gy). Eleven patients (22%) developed progressive disease after radiation therapy at a median time of 41 months (range 12-113 months). The recurrences were within the radiation therapy field in four patients and outside the field in seven patients. One patient developed a radiation-induced malignancy 20 years after treatment.

CONCLUSIONS

Radiation therapy is an alternative treatment in the management of desmoid fibromatosis. It should be considered in patients for whom surgical resection is not feasible, or as adjuvant therapy after surgery with involved margins where any further recurrences would cause significant morbidity.

Sporadic desmoid-type fibromatosis: a stepwise approach to a non-metastasising neoplasm--a position paper from the Italian and the French Sarcoma Group

Desmoid-type fibromatosis (DF) is a rare locally aggressive monoclonal proliferation of myofibroblasts lacking metastatic capacity. It may be observed in nearly every part of the body. Considering the variable clinical presentations, anatomic locations, and biologic behaviors, an individualized treatment approach is required. The pathogenesis of DF is not completely understood even if a high prevalence (∼85%) of CTNNB1 mutations discovered in sporadic DF underlies the importance of the Wnt/β-catenin pathway. No established and evidence-based approach for the treatment of this neoplasm is available as of today. Considering the unpredictable behavior and the heterogeneity of this disease, we propose a treatment algorithm approved by the French and the Italian Sarcoma Group, based on a front-line wait and see approach and subsequent therapy in the case of progression. A careful counseling at a referral center is mandatory and should be offered to all patients affected by sporadic DF from the time of their diagnosis.

Aggressive fibromatosis in children: a changing approach

Desmoid tumor, also known as aggressive fibromatosis (AF), is a rare monoclonal, fibroblastic proliferation arising in musculoaponeurotic structures. AF is a tumor of intermediate malignancy, with a strong potential for local invasiveness and recurrence. The treatment of choice for these tumors has been changing all the time and may involve surgery, radiotherapy and/or systemic approaches. Surgery generally used to be considered the mainstay of treatment for AF, its goal preferably being a microscopically complete resection with histologically free margins. Mutilating surgery or procedures causing significant loss of function and/or chronic symptoms should be avoided. Involvement of surgical margins is probably associated with an increased risk of local recurrence. Postoperative radiotherapy could be used in cases with positive margins after surgery, or to avoid mutilating surgery in cases of inoperable or inaccessible disease. Postoperative radiotherapy has been reported to raise local disease control to a level similar to that of complete resection, but is associated with a relatively high rate of complications. Systemic treatment may be indicated in case of locally-advanced disease. Several risk factors for local recurrence have been investigated and include: young age, large size, presentation as recurrence, girdles or intra-abdominal location, involved surgical margins, and β-catenin-activating mutations. Recently collected data prompted the suggestion that these tumors warrant a wait-and-see strategy (clinical-radiological observation, without any treatment), since their natural history is often characterized by lengthy periods of stability or even regression, considering to treat only patients with progressing or symptomatic disease.

An evaluation of brachytherapy and external beam radiation used with wide-margin surgical resection in the treatment of extra-abdominal desmoid tumors

Surgical resection has had control rates of 53% to 77% in the treatment of extra-abdominal desmoid tumors. Surgical excision combined with external beam radiation therapy (EBRT) has had local control rates of up to 83% in some series. The purpose of this study was to evaluate the effectiveness of resection combined with radiotherapy (brachytherapy, EBRT, or both) in the treatment of extra-abdominal desmoid tumors. We retrospectively reviewed the charts of 24 consecutive patients (27 histologically confirmed extra-abdominal desmoid tumors). Patients were included in the study if they had a lesion that was potentially resectable with a wide margin, allowing for limb salvage, and if they did not have a contraindication to radiotherapy. Limb functioning was assessed with the Musculoskeletal Tumor Society (MSTS) scoring system. Seventeen patients (7 men, 10 women) with 19 tumors met the inclusion criteria. Mean age at diagnosis was 23.4 years. Follow-up (mean, 4.28 years) involved serial clinical examinations and magnetic resonance imaging of tumor sites. After surgery, the tumors were treated with brachytherapy (n = 6), EBRT (n = 10), or both (n = 3). Two of the 17 tumors in patients with negative margins of resection recurred locally (local control rate, 88.2%). Mean MSTS score was 29/30 (96.7%). The role of surgery, radiotherapy, chemotherapy, hormone therapy, and other treatments for extra-abdominal desmoid tumors is not well defined. When wide-margin resection and radiotherapy can be performed with limb preservation surgery, local control and complication rates compare favorably with those of other reported methods of treatment. Given the results and limitations of our study, we cannot make a definitive recommendation as to which modality--brachytherapy or EBRT--should be used in the treatment of extra-abdominal desmoid tumors.

[Radiation therapy in extra abdominal desmoid tumours]

BACKGROUND

Desmoid tumours are rare benign tumours that have local "malignity". They can be locally aggressive by infiltrating adjacent vascular, nervous and bony structures.

AIM

To define the role of radiotherapy in the management of desmoid tumours.

METHODS

Retrospective study of six extra-abdominal desmoid tumours treated with surgery and radiation therapy.

RESULTS

Median age was 26.8 years (16-35 years). The tumor was located in the arm (1 case), in the legs (2 cases) and in the body (3 cases). Median tumoral sizes were 86.6 mm (60-100 mm). Five patients had local recurrence after surgical resection. Radiation therapy included Cobalt 60 in five cases and photons associated to linear acceleration in one case. Total dose was between 54 and 62 Gy. At the end of radiation therapy, tumoral control was obtained in five cases after a median follow-up of 26 months (1-83 months).

CONCLUSION

Surgery is the main treatment of desmoids tumours but local recurrence rates remain high even after complete resection. The role of adjuvant radiation therapy is controversial.

[Desmoid tumours in the abdominal wall]

Desmoid tumours are benign tumours originating from musculoaponeurotic structures and the fascia. They usually are slow-growing, without metastatic potential. However, their local behaviour can be infiltrative and aggressive, leading to damage of adjacent structures causing organ dysfunction. They carry a high risk of relapse. In this paper, three case studies of women aged 33, 35 and 42 years, respectively, illustrate the presentation, diagnostics and therapy of abdominal desmoid tumours. All three were surgically treated and recovered. Desmoid tumours occur most commonly in fertile women. Although the etiology is unknown, there is a correlation with scar tissue, pregnancy and radiotherapy. Abdominal desmoid tumours have the lowest relapse rate of all desmoid tumours. In toto resection is the treatment of choice. Radiotherapy in addition to surgery may be considered when risk of relapse is high.

[Evaluation of prognostic factors affecting recurrences and disease-free survival in extra-abdominal desmoid tumors]

OBJECTIVES

We investigated treatment results and the role of potential prognostic factors in patients treated by surgery with or without adjuvant radiotherapy for primary or recurrent extra-abdominal desmoid tumors.

METHODS

The study included 38 patients (23 females, 15 males; mean age 24 years; range 5 to 61 years) who underwent surgical treatment for extra-abdominal desmoid tumors. Of these, eight patients (21.1%) already had recurrences before treatment. Involvement was in the upper extremity in 12 cases (31.6%), in the lower extremity in 22 cases (57.9%), and in the axial region in four cases (10.5%). Twenty-two patients received adjuvant radiotherapy following surgical resection. Survival was analyzed by the Kaplan-Meier method. The mean follow-up period was 7.3 years (2.5 to 228 months).

RESULTS

Twenty patients (52.6%) developed recurrences after treatment. Of these, recurrences were already present in six patients, and adjuvant radiotherapy was administered to 11 patients (55%). Recurrences developed at the irradiated site in eight patients, and in other regions in three patients. The mean disease-free survival was 38+/-8 months, and eight-year disease-free survival was 35.7+/-8.5%. Disease-free survival did not differ significantly between patients receiving adjuvant radiotherapy (47.9+/-7.9 months) and those treated with surgery alone (37.9+/-12.4 months), and between patients who developed a recurrence at the resection site (12.1+/-4.7 months) or at a different site (24.3+/-1.0 months) (p>0.05). None of the potential prognostic factors including gender, age, localization, surgical margin, or adjuvant irradiation were found to affect disease-free survival.

CONCLUSION

In our series, no prognostic factor could be identified as having an association with the high recurrence rate.

Desmoid-type fibromatosis involving the brachial plexus

✓Desmoid-type fibromatosis involving the brachial plexus is a rare and challenging disease. Due to involvement of crucial neurovascular structures, wide local excision of the associated fibromas is rarely feasible and recurrence is common. The authors describe their experience in four surgically treated patients with desmoid-type fibromatosis involving the brachial plexus and review the relevant neurosurgical literature.

All tumors were assessed for c-KIT oncogene mutations in hopes of establishing a biological basis for using the tyrosine kinase inhibitor imatimib mesylate as an adjuvant therapy. Three patients experienced tumor recurrence requiring reoperation. Fractionated radiotherapy achieved local control in three patients, and the disease in one patient progressed beyond the treatment field. Single base pair changes at exon 10 of the c-KIT oncogene were identified in three tumors. One tumor with this mutation did not respond to treatment with imatimib mesylate. A review of the literature revealed 17 additional patients in two different case series. Analysis of these cases emphasizes the need for careful resection in patients with desmoid-type fibromatosis and supports the conclusion that without adjuvant radiotherapy a high local recurrence rate can be anticipated. For optimal local disease control, the authors recommend post-surgical radiation therapy regardless of the extent of resection achieved. The mutational status of the c-KIT oncogene remains an intriguing biological marker that in the future may predict which lesions will be responsive to imatimib mesylate; larger series will be necessary to test this hypothesis.

Optimizing Treatment of Desmoid Tumors

Purpose

This study compared a large series of desmoid patients treated at a single institution to a previously published series from the same institution to determine if patient population characteristics, treatment approaches, and clinical outcomes had undergone change over the two study periods.

Materials and Methods

Data from a prospective soft tissue tumor database was used to analyze clinical courses of 189 desmoid patients treated at The University of Texas M.D. Anderson Cancer Center (UTMDACC) from 1995 to 2005 as compared with 189 UTMDACC desmoid patients treated between 1965 and 1994.

Results

A nearly three-fold increase in annualized UTMDACC desmoid referral volume with significantly higher percentages and numbers of primary desmoid tumor referrals to UTMDACC was observed in the most recent study period. Significantly increased systemic therapy use and decreased reliance on surgery alone was observed more recently. While the recent series patients had higher rates of macroscopic residual disease and equivalent rates of positive microscopic margins after definitive surgery, the estimated 5-year local recurrence rate of 20% was improved compared with the 30% rate observed in the earlier series.

Conclusion

Increased awareness of the complex multidisciplinary management needed for desmoid tumor control may underlie significantly increased numbers of referrals to UTMDACC, especially primary untreated desmoids. Increased neoadjuvant treatments may be associated with improved desmoid patient outcomes. These trends should be supported, particularly if personalized molecular-based therapies are to be rapidly and effectively deployed for the benefit of those afflicted by this rare and potentially debilitating disease.

Fibromatosis: benign by name but not necessarily by nature

Aggressive fibromatoses, also known as desmoid tumours, are rare fibrous tissue proliferations with a tendency for slow, local infiltrative growth. There is an association with Gardner's syndrome and familial adenomatous polyposis. Histologically they are fairly bland with no abnormal mitoses or necrosis. They do not metastasize, but can cause significant morbidity through their locally destructive effects. Magnetic resonance imaging is the method of choice for diagnosis, pre-treatment planning and post-treatment follow-up. Surgical excision with a wide margin is the treatment of choice. However, there is a tendency for local recurrence and repeated excision may result in a poor functional or cosmetic outcome. Radiotherapy is used to reduce local recurrence rates after excision and is also used to treat inoperable tumours. Long-lasting remissions can be obtained. Treatment is now planned using modern three-dimensional conformal techniques, similar to those used in soft tissue sarcoma management. There is no definite dose-response relationship, but doses of 50-60 Gy in 1.8-2 Gy fractions are recommended. Systemic therapy has been used for lesions not controlled by surgery or radiotherapy, or less commonly, as a primary treatment. Tamoxifen and non-steroidal anti-inflammatory agents are used most often as they are relatively non-toxic, but there is limited experience with cytotoxic chemotherapy and biological agents. There are no randomised trials to help guide the management of this locally aggressive 'benign' tumour and treatment decisions are best made by the local soft tissue sarcoma multidisciplinary team.

The impact of radiotherapy in the treatment of desmoid tumours. An international survey of 110 patients. A study of the Rare Cancer Network

Purpose

A multi-centre study to assess the value of combined surgical resection and radiotherapy for the treatment of desmoid tumours.

Patients and methods

One hundred and ten patients from several European countries qualified for this study. Pathology slides of all patients were reviewed by an independent pathologist. Sixty-eight patients received post-operative radiotherapy and 42 surgery only. Median follow-up was 6 years (1 to 44). The progression-free survival time (PFS) and prognostic factors were analysed.

Results

The combined treatment with radiotherapy showed a significantly longer progression-free survival than surgical resection alone (p smaller than 0.001). Extremities could be preserved in all patients treated with combined surgery and radiotherapy for tumours located in the limb, whereas amputation was necessary for 23% of patients treated with surgery alone. A comparison of PFS for tumour locations proved the abdominal wall to be a positive prognostic factor and a localization in the extremities to be a negative prognostic factor. Additional irradiation, a fraction size larger than or equal to 2 Gy and a total dose larger than 50 Gy to the tumour were found to be positive prognostic factors with a significantly lower risk for a recurrence in the univariate analysis. This analysis revealed radiotherapy at recurrence as a significantly worse prognostic factor compared with adjuvant radiotherapy. The addition of radiotherapy to the treatment concept was a positive prognostic factor in the multivariate analysis.

Conclusion

Postoperative radiotherapy significantly improved the PFS compared to surgery alone. Therefore it should always be considered after a non-radical tumour resection and should be given preferably in an adjuvant setting. It is effective in limb preservation and for preserving the function of joints in situations where surgery alone would result in deficits, which is especially important in young patients.

[Desmoid tumors of the head and neck]

Desmoid tumors of the head and neck, also known as aggressive fibromatoses, are rare. They are soft tissue neoplasms arising from musculoaponeurotic structures and characterized of locally aggressive infiltration and recurrences. Complete surgical excision of desmoid tumors is considered to be the only effective method of cure. It is likewise important to make a function-preserving surgery. In addition to the radicality this aspect should be a primary goal to minimize morbidity. MRI is the first choice in the preoperative evaluation of neck desmoids. We describe the successful treatment of desmoid tumors in two cases (M. sternocleidomastoideus, M. levator scapulae). Intraoperative neuromonitoring was very helpful for identification and protection of the motor nerves.

Tamoxifen for recurrent desmoid tumor of the chest wall

We report a case of a young woman with recurrent desmoid tumor. Computed tomography (CT) scans of the chest showed a large mass in the left chest wall. The tumor was unresectable because of the involvement of adjacent structures. Tamoxifen therapy led to marked tumor regression within 3 months. She had preserved her fertility, and thereafter she conceived a baby. In young women with recurrent desmoid tumor, tamoxifen should be considered as the first choice of treatment.

Combined administration of ethodolac, ascorbic acid and radiotherapy as adjuvant therapies in an extrathoracic desmoid tumor with gross postoperative residual disease; case report and review of the literature

A 37-year-old man was admitted with an extrathoracic desmoid tumor invading the brachial plexus. Magnetic resonance imaging (MRI) of the thorax demonstrated a 20 x 9 x 14 cm mass in the supraclavicular fossa, axillary fossa and the right side of the chest. It invaded the brachial plexus and circumscribed the subclavian and axillary arteries concentrically. Biopsy revealed desmoid tumor which was resected subtotally with the brachial plexus. The gross residual mass was treated postoperatively with radiotherapy (60 Gy) which resulted in major regression of the mass. Following radiotherapy, ethodolac with ascorbic acid were administered. The tumor was clinically indiscernible 35 months post-radiotherapy. This case shows the high effectiveness of radiotherapy along with less toxic medical treatment modalities in instances where local control is hard to achieve with surgery and highlights the importance of using multidisciplinary treatments to maintain good functional results.

Aggressive fibromatosis--impact of prognostic variables on management

OBJECTIVE

To determine the impact of prognostic variables on local control in patients with aggressive fibromatosis treated with or without radiation.

MATERIALS AND METHODS

Forty-two patients presenting to the combined sarcoma clinic at Johannesburg Hospital with aggressive fibromatosis from 1990 to 2003 were analysed retrospectively. There were 14 males and 28 females. The lesions involved the head and neck in 6 cases (14%), the thorax in 6 (14%), the extremities in 19 (45%) and the abdomen in 11 (26%). Thirty-seven patients (88%) presented to the clinic for the first time, whereas 5 (12%) had recurrent disease at presentation. Fifteen patients (36%) underwent excision only, 15 (36%) had excision followed by postoperative radiation, 8 (19%) had biopsy only, and 4 (9%) had radiation only. The median dose of radiation was 60 Gy (range 9 - 70 Gy).

RESULTS

One patient had local failure following excision and postoperative radiation therapy. The local control was 100% for surgery alone and 86% for surgery followed by postoperative radiation at > or = 24 months. On univariate analysis, age, sex, positive margins, primary or recurrent presentation, site of involvement and initial treatment did not affect local control significantly. Eight of 19 patients (42%) receiving radiation developed severe moist desquamation following treatment, and all these patients had doses of 60 Gy or more.

CONCLUSION

Surgery with or without radiation therapy gave excellent local control. The addition of radiation therapy to surgery as well as other known prognostic parameters did not impact on local control. The morbidity of radiation treatment is considerable, as noted in this series, and adjuvant radiation therapy should therefore be considered only in situations where the risk of recurrence and the morbidity of re-excision are high.

Desmoid tumor of the head and neck

BACKGROUND

[corrected] Desmoid tumors are rare benign tumors but have a tendency toward local recurrence after resection because of their infiltrative growth and frequent entrapment of vital structures in the head and neck region. We report 24 desmoid tumors of the head and neck and propose a reasonable approach in the management of such cases.

METHODS

Twenty-four patients (9 male and 15 female; median age, 33 years; range, 0-66 years) with a desmoid tumor of the head and neck (neck, 15 patients; head, 9 patients) treated from 1990 to 2004 were retrospectively analyzed. The size ranged from 0.5 to 13 cm in diameter (mean, 3.6 cm). In the neck, 8 tumors were around the superficial layer of deep cervical fascia, whereas 4 tumors of the neck involved the prevertebral fascia and 2 involved brachial plexus.

RESULTS

Twenty patients received complete resection of the tumor, but the section margin was positive in 8 patients, of which 6 patients remained free of disease in a period of 13 to 105 months. Three patients, including 2 with positive section margin and 1 with negative margin, developed recurrences, which were successfully removed again. Two patients underwent partial resection of the tumor because of brachial plexus involvement. One of them achieved regression after postoperative radiotherapy and the other had spontaneous regression. The hypopharygneal tumor in a newborn had spontaneously complete regression, and tracheostomy was closed at the age of 6 years. One patient remained with stable disease for 14 months after biopsy of the tumor without excision.

CONCLUSION

The overall prognosis is still good despite frequent incomplete resection. Surgical resection of the tumor with close observation is suggested even if the section margin is positive. If a desmoid tumor cannot be removed grossly, regression or arrested growth of the remaining tumor is expected. Radiotherapy might be reserved for a growing tumor.

Radiation Myelopathy Visualized as Increased FDG Uptake on Positron Emission Tomography

A woman with a history of desmoid tumor involving the T9-T10 vertebrae was treated with local irradiation. After treatment, she developed tingling sensations in both legs. An FDG PET study demonstrated focally increased activity posterior to the vertebral bodies at the levels of T9-T10, which was vertical in orientation, corresponding to the location of the spinal cord at this level. This finding is consistent with the clinical suspicion of radiation myelopathy.

Radiation therapy for aggressive fibromatosis (desmoid tumors): results of a national Patterns of Care Study

PURPOSE

After a general Patterns of Care Study (PCS) the German Cooperative Group on Radiotherapy for Benign Diseases (GCG-BD) initiated a multicenter cohort study to analyze the radiation therapy practice for aggressive fibromatosis.

METHODS AND MATERIALS

In 2002 a PCS was conducted in all German radiotherapy (RT) institutions by mailing a standardized structured questionnaire, to assess patients accrual, number, pretreatment, treatment indications, RT, and target volume concepts for irradiation in aggressive fibromatosis. In addition, the treatment outcome of individual patients was evaluated. The PCS was structured and analyzed according to the model for quality assessment by Donabedian in three major components: structure, process, and outcome evaluation.

RESULTS

A total of 101 institutions returned the questionnaire: 52.7% reported satisfactory clinical data and experience for inclusion in this analysis. A total accrual rate of 278 patients per year was reported with median number of 2 cases (1-7 cases) per institution. Satisfactory data for a long-term clinical evaluation was reported for 345 patients from 19 different institutions. The applied total doses ranged between 36 and 65 Gy (median, 60 Gy). The local control rate was 81.4% in primary RT for unresectable tumors and 79.6% in postoperative RT. No acute or late radiation toxicities > Grade 2 (RTOG) were observed. No clear dose-response relationship could be established, but there was a tendency toward a lower local control rate in patients with a higher number of operative procedures before RT and patients treated for recurrent aggressive fibromatosis.

CONCLUSIONS

This study comprises the largest database of cases reported for RT in aggressive fibromatosis. Radiotherapy provides a high local control rate in the postoperative setting and in unresectable tumors. This PCS may serve as a starting point for a national or international prospective multicenter study or registry, or both.

Desmoidfibromatosen (aggressive Fibromatosen)

Desmoid-type fibromatoses (aggressive fibromatoses) represent infiltrative, locally destructively growing soft tissue tumors with a high potential for recurrence. Desmoid tumors of 33 adult patients were analysed regarding clinical and morphological aspects (sex, age distribution, site, size, mitotic rate, tumor microvessel density, surgical margins, additional radiotherapy). Possible statistical correlations were examined using log-rank-tests. No prognostic significance of tumor microvessel density was evident. A correlation between mitotic index (1 or more mitoses per 50 high power fields) and local relapse rate was notably striking, but not statistically significant (log-rank: 0.17). Additional postoperatively applied radiotherapy proved to be statistically significant to avoid local recurrences (log-rank: 0.01). The presented results may indicate an increased risk for local relapse in those desmoid-type fibromatoses which are mitotically active. Postoperative radiotherapy seems to be effective in the treatment of aggressive fibromatosis to avoid tumor recurrence. Differential diagnosis of desmoid-type fibromatosis/aggressive fibromatosis in adulthood include various fibroblastic/myofibroblastic soft tissue tumors such as nodular fasciitis, fibrosarcoma, low-grade fibromyxoid sarcoma, myofibroblastic sarcoma as well as leiomyosarcoma and soft tissue leiomyoma.